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Ecological Consequences of Artificial Night Lighting: Bibliography


This bibliography is a companion to the conference Ecological Consequences of Artificial Night Lighting. To suggest additions or make corrections, please email Some are references included from other online bibliographies, including those maintained by the Conservation Management Institute and Pierantonio Cinzano.

This resource is not regularly updated. All of our recent effort has been directed toward editing the book Ecological Consequences of Artificial Night Lighting. If you have specific questions about this topic that need to be answered before the book released in November 2005, please email us at Follow this link for more information about the book and to order your copy.



general | plants | aquatic invertebrates | terrestrial invertebrates | amphibians | sea turtles | other reptiles | fish | birds | seabirds | mammals



Borg, V. (1996). Death of the night. Geographical Magazine. 68: 56.
Night light pollution is becoming an increasingly important environmental problem as well as an impediment to people enjoying the panorama offered by the stars. Certain animals, such as sea turtles in the Mediterranean and migratory birds that fly by night, are disturbed in their reproductive and migratory habits by the excess light being given off by lit towns and cities. The answer is to cap night lights to reduce the glare that is given off into the sky.

Fedun, I. (1995). Fatal Light Attraction. Journal of Wildlife Rehabilitation 18(3):10-11.

Harder, B. (2002). "Deprived of darkness: the unnatural ecology of artificial light at night" Science News 161(16):248-249.

Health Council of the Netherlands. 2000. Impact of outdoor lighting on man and nature. The Hague: Health Council of the Netherlands. Publication no. 2000/25E. (

Raevel P. & Lamiot, F. (1998). Impacts écologiques de l'éclairage nocturne. Premier Congrès européen sur la protection du ciel nocturne, June 30-May 1, Cité des Sciences, La Villette, Paris.

Outen, A. (1998). The possible ecological implication of artificial lighting. Hertfordshire, UK: Hertfordshire Biological
Records Centre.

Upgren, A. R. (1996). "Night blindness: Light pollution is changing astronomy, the environment, and our experience of nature." The Amicus Journal Winter:22-25.

Verheijen, F. J. (1958). "The mechanisms of the trapping effect of artificial light sources upon animals." Netherlands Journal of Zoology 13:1-107.

Verheijen, F. J. (1985). "Photopollution: Artificial light optic spatial control systems fail to cope with. Incidents, causations, remedies." Experimental Biology 1985:1-18.


Edwards, D. G. W. and Y. A. El-Kassaby (1996). "The effect of stratification and artificial light on the germination of mountain hemlock seeds." Seed Science and Technology 24(2): 225-235.
Germination in mountain hemlock, Tsuga mertensiana (Bong.) Carr., was investigated using 19 seed sources from British Columbia. Neither light nor stratification for 28 days had any significant effect on germination capacity, but light significantly (p less than or equal to 0.01) reduced germination rate. Stratification significantly increased germination rate in all seed sources, although the amount of total variation attributable to this effect was small. Stratification did not overcome the effect of light, and it is recommended that seeds should be covered after sowing in the nursery. All sources, including one from the interior of the province, germinated relatively uniformly. No correlations could be found between germination parameters and age, source elevation and seed weight, but germination capacity and seed weight were correlated with latitude. No correlation existed between seed weight and elevation. For most sources, a test duration of 21 days was adequate for complete germination even of unstratified seeds. Mountain hemlock seeds should be stratified before being sown in the nursery, and they should be covered during the germination phase to exclude light.

Aquatic Invertebrates

Moore, M.V., S.M. Pierce, H.M. Walsh, S.K. Kvalvik, and J.D. Lim (2000). Urban light pollution alters the diel vertical migration of Daphnia. Proceedings of the International Society of Theoretical and Applied Limnology. In press.

Pierce, S.M. and M.V. Moore (1998). Light pollution affects the diel vertical migration of freshwater zooplankton. Abstract, 1998. Annual Meeting of the Ecological Society of America, Baltimore, MD.

Peterson, Aili (2001). Night lights. Science Observer. January-February. Online:

Terrestrial Invertebrates

Bhattacharya, A., Y. D. Mishra, et al. (1995). "Attraction of some insects associated with lac towards various coloured lights." Journal of Insect Science 8(2):205-206.
Three different colours of light, i.e., blue, yellow and red along with natural light has been tested to find out the degree of photo-attraction of eight insect species found in the biotic complex around lac insect. All the eight species tested showed high degree of attraction towards natural light and least for blue. Marked differences have also been observed in the behaviour of the predators and parasitoids for yellow and red colour lights.

Craig, C. L. and C. R. Freeman (1991). "Effects of predator visibility on prey encounter: A case study on aerial web weaving spiders." Behavioral Ecology and Sociobiology 29(4):249-254.
Perhaps the most important factor affecting predator-prey interactions is their encounter probability. Predators must either locate sites where prey are active or attract prey to them, and prey must be able to recognize potential and flee before capture. In this study we manipulate and describe three components of the foraging system of predatory, web-weaving spiders, the presence of viscid droplets, silk brightness (achromatic surface reflectance), and visibility of the orb pattern, to determine their effect on insect attraction, recognition, and web avoidance. We found that webs with viscid droplets were more visible to prey at close range, but at greater distances the sparkling droplets lured insects to the web area and hence increased insect capture probability. Although the size of viscid droplets and silk brightness are closely correlated (Table 2, Fig. 3), the relationships among droplet size, spider size, and the visual environments in which webs are found are more complicated (Fig. 2, Tables 2, 3). In environments with predictable light exposure, droplet size and hence milk visibility correlate with spider size, and spiders that forage at night produce relatively more visible silks then spiders that forage during the day (Table 3, Fig. 4). In habitats in which light levels are not predictable, silk surface reflectance and spider size are not closely correlated, suggesting that the complexity of the light environment, as well as the visual and foraging behaviors of insects found there, has played an important role in the evolution of spider-insect interactions.

Eisenbeis, G. and F. Hassel (2000) "[Attraction of nocturnal insects to street lights - a study of municipal lighting systems in a rural area of Rheinhessen (Germany.]" Natur und Landschaft 75(4):145-156.
Street lamps which illuminate public areas and places at night are of different types, emitting different spectra. All of them (e.g. white mercury (HME), orange sodium (HSE) or sodium-xenon vapour lamps (HSXT)) attract insects. During summer nights, myriads of insects fly restlessly around the lamps, which therefore have a marked impact on insect biology. There is some evidence that lamps differ with respect to their insect attraction. Sodium lamps, for instance, attract insects less strongly than white mercury lamps. We tested the attraction of three lamp types and, in addition, an ultraviolet absorber foil and some controls (lights without illumination). All installations were carried out by the electric utility of Rheinhessen/Germany (EWR) at three sites in a rural area. To trap insects, we used 19 air-eclector traps which had been positioned within the light cones of the street lights. We caught a total of 44,210 insects (including some arachnids), distributed among 12 orders. Altogether the data set comprised 536 night trapping records. The results show that the number of insects captured at the three sites and the attraction per eclector per day depends significantly on both the type of lamp and the site. By using sodium vapor street lamps (HSE), the number of insects caught was reduced signficantly by more than 50%, and in the case of Lepidoptera by about 75%. We therefore recommend the use of sodium high pressure vapour lamps to improve the conservation of insect fauna. The results further show that there is a large potential to reduce costs for municipalities by switching street illumination from mercury vapour (HME) to sodium vapour (HSE) lamps.

Frank, K. D. (1988). "Impact of outdoor lighting on moths: An assessment." Journal of the Lepidopterists' Society 42(2):63-93.
Outdoor lighting has sharply increased over the last four decades. Lepidopterists have blamed it for causing declines in populations of moths. How outdoor lighting affects moths, however, has never been comprehensively assessed. The current study makes such an assessment on the basis of published literature. Outdoor lighting disturbs flight, navigation, vision, migration, dispersal, oviposition, mating, feeding and crypsis in some moths. In addition it may disturb circadian rhythms and photoperiodism. It exposes moths to increased predation by birds, bats, spiders, and other predators. However, destruction of vast numbers of moths in light traps has not eradicated moth populations. Diverse species of moths have been found in illuminated urban environments, and extinctions due to electric lighting have not been documented. Outdoor lighting does not appear to affect flight or other activities of many moths, and counterbalancing ecological forces may reduce or negate those disturbances which do occur. Despite these observations outdoor lighting may influence some populations of moths. The result may be evolutionary modification of moth behavior, or disruption or elimination of moth populations. The impact of lighting may increase in the future as outdoor lighting expands into new areas and illuminates moth populations threatened by other disturbances. Reducing exposure to lighting may help protect moths in small, endangered habitats. Low-pressure sodium lamps are less likely than are other lamps to elicit flight-to-light behavior, and to shift circadian rhythms. They may be used to reduce adverse effects of lighting.

Gerson, E. A. and R. G. Kelsey (1997). "Attraction and direct mortality of pandora moths, Coloradia pandora (Lepidoptera: Saturniidae), by nocturnal fire." Forest Ecology and Management 98(1):71-75.
The attraction of nocturnal moths to candles and other sources of light has long been observed, but fire as a potential source of mortality to moths in ecosystems with frequent fire regimes has been overlooked. A prescribed burn was conducted shortly after dark in a central Oregon ponderosa pine forest during the flight period of the endemic defoliator Coloradia pandora (Blake). Attraction to the fire and partial consumption by flames caused direct mortality estimated at 2.2% to 17.1% of the local pandora moth population. In field tests with projected light, pandora moths did not discriminate among colors in the visible spectrum. Moths did not respond to projected light for at least 1 h after dusk, indicating that timing and duration of the prescribed fire may have limited the mortality.

Gotthard, K. (2000). "Increased risk of predation as a cost of high growth rate: An experimental test in a butterfly." Journal of Animal Ecology 69(5):896-902.
1. Life history theoreticians have traditionally assumed that juvenile growth rates are maximized and that variation in this trait is due to the quality of the environment. In contrast to this assumption there is a large body of evidence showing that juvenile growth rates may vary adaptively both within and between populations. This adaptive variation implies that high growth rates may be associated with costs. 2. Here, I explicitly evaluate the often-proposed trade-off between growth rate and predation risk, in a study of the temperate butterfly, Pararge aegeria (L). 3. By rearing larvae with a common genetic background in different photoperiods it was possible to experimentally manipulate larval growth rates, which vary in response to photoperiod. Predation risk was assessed by exposing larvae that were freely moving on their host plants to the predatory heteropteran, Picromerus bidens (L.). 4. The rate of predation was significantly higher in the fast-growing larvae. An approximately four times higher relative growth rate was associated with a 30% higher daily predation risk. 5. The main result demonstrates a trade-off between growth rate and predation risk, and there are reasons to believe that this trade-off is of general significance in free-living animals. The results also suggest that juvenile development of P. aegeria is governed by a strategic decision process within individuals.

Heiling, A. M. (1999). "Why do nocturnal orb-web spiders (Araneidae) search for light?" Behavioral Ecology and Sociobiology 46(1):43-49.
The nocturnal orb-web spider Larinioides sclopetarius lives near water and frequently builds webs on bridges. In Vienna, Austria, this species is particularly abundant along the artificially lit handrails of a footbridge. Fewer individuals placed their webs on structurally identical but unlit handrails of the same footbridge. A census of the potential prey available to the spiders and the actual prey captured in the webs revealed that insect activity was significantly greater and consequently webs captured significantly more prey in the lit habitat compared to the unlit habitat. A laboratory experiment showed that adult female spiders actively choose artificially lit sites for web construction. Furthermore, this behaviour appears to be genetically predetermined rather than learned, as laboratory-reared individuals which had previously never foraged in artificial light exhibited the same preference. This orb-web spider seems to have evolved a foraging behaviour that exploits the attraction of insects to artificial lights.

Kolligs, D. (2000). "Ecological effects of artificial light sources on nocturnally active insects, in particular on butterflies (Lepidoptera)." Faunistisch-Oekologische Mitteilungen Supplement 28:1-136.
It is a well known phenomena that night-active insects are attracted by artificial light sources. With a growing urban environment and a high number of street lamps and other light emitting sources, the response of night active insects to artificial light becomes of in-creasing importance for nature protection. This study focuses on the behavioural response of different insect orders, families and species to the most frequently used exterior lighting and street lamps (mercury- and sodium-vapour lamps). These artificial sources of light distinctly increased in the last decades. In the city of Kiel (North-Germany) the number of streetlights was fifty times higher in 1998 than in 1949. The investigations were carried out at two sites in Schleswig-Holstein (North-Germany): in Albersdorf / Dithmarschen (western Schleswig-Holstein) and in Kiel on the university campus (eastern Schleswig-Holstein). In Albersdorf, the insects were attracted by a light emitting greenhouse (10,000 m2) and by two punctually radiating light sources (light traps with mercury and sodium-vapour lamps) and became comparative investigated in 1994 to 1995. Two different methods were used to record insects at the greenhouse. Butterflies (Lepidoptera) were sampled by hand. The remaining insects were trapped in two 1.5 m2 large sample areas using a suction trap. Insects from each of the four sides of the green-house were sampled and trapped separately. The two light traps caught the insects automatically. On the campus of Kiel University insects were studied from 1994 to 1996. For this purpose four street lamps equipped with mercury-vapour lamps had traps attached to the socket. On one of the four street lamps the mercury-vapour lamp was exchanged by a sodium-vapour lamp with the same light intensity. In 1996 two additional street lamps were equipped with a different type of trap. 72,267 insects from 114 insect families and 96,725 insects from 138 families were redorded at Albersdorf and at Kiel, respectively. Butterflies (Lepidoptera), beetles (Coleoptera), caddies flies (Trichoptera) and sciarid flies (Sciaridae) were determined to the species level. An analysis of the catches gave the following resuits: Mosquitos (Nematocera) made up the majority of all captured insects (40 - 90 %). The other most conunon groups were butterflies (Lepidoptera), flies (Brachycera) and beetles (Coleoptera). In both study areas Hymenopterans (Hymenoptera), aphids (Aphidina), cicadas (Cicadina), true bugs (Heteroptera), neuropterans (Neuroptera), caddis flies (Trichoptera), psocids (Psocoptera) and mayflies (Ephemeroptera) made up less than 1 % of the total catch. Catches from adjacent street lamps (25 m apart) were distinctly different in their insect compositions. These differences seem to be caused by the surrounding habitats and the wind exposure of the lamps. Significant differences between the compositions of samples from different street lamps were oniy found between May and the end of August. In spring and autumn the sample 13 sizes were small and species compositions were not significantly different. In contrast to hand sampling not all insects that flew into street lamps were caught by the automatic light traps (e. g. only 30-40 % of the Lepidoptera were caught by the traps) No significant correlation was found between the size of a light source and the number of Lepidoptera attracted by it. Rather the intensity and the light spectrum seem to control butterfly abundance at a light source. The light spectrum of the sodium-vapour lamp attracted fewer species and individuals than the mercury-vapour lamp. Otherwise from some species, e.g. he swift mohs (Hepialidae) or the geometric moth Idaea dimidiata, more individuals were registrated at the sodium-vapour lamps. Only single individuals of endangered butterfly species were found at the different light sources, while 31 beetle species of the Red List of Schleswig-l-Iolstein were captured in the study area in Kiel.

Klotz, J. H. and B. L. Reid (1993). "Nocturnal orientation in the black carpenter ant Camponotus pennsylvanicus Degeer (Hymenoptera: Formicidae)." Insectes Sociaux 40(1):95-106.
The black carpenter ant Camponotus pennsylvanicus (DeGeer), a predominantly nocturnal Formicine ant, responds to a hierarchy of visual and tactile cues when orienting along odor trails at night. Under illumination from moonlight or artificial light, workers rely upon these beacons to mediate phototactic orientation. In the absence of moonlight or artificial lights, ants were able to orient visually to terrestrial landmarks. In the absence of all landmarks, save for overhanging tree branches, ants could negotiate shortcuts or make directional changes in response to visual landmarks presented within the tree canopy on a moonless night. When experimental manipulations placed the ants in total darkness, they could no longer negotiate shortcuts and would resort to thigmotactic orientation along structural guidelines to reach a food source. The hierachical organization of these diverse cues in a foraging strategy is discussed, as well as their adaptive significance to C. pennsylvanicus.

Sivinski, J. M. (1998). "Phototropism, bioluminescence, and the Diptera." Florida Entomologist 81(3):282-292.
Many arthropods move toward or away from lights. Larvae of certain luminescent mycetophilid fungus gnats exploit this response to obtain prey. They produce mucus webs, sometimes festooned with poisonous droplets, to snare a variety of small arthropods. Their lights may also protect them from their own negatively phototropic predators and/or be used as aposematic signals. On the other hand, lights may aid hymenopterous parasitoids to locate fungus gnat hosts. The luminescence of mushrooms can attract small Diptera, and might have evolved to aid mechanical spore dispersal. Among Diptera, bioluminescence is found only in the Mycetophilidae, but the variety of light organs in fungus gnats suggests multiple evolutions of the trait. This concentration of bioluminescence may be due to the unusual, sedentary nature of prey capture (i.e., use of webs) that allows the 'mimicry' of a stationary abiotic light cue, or the atypically potent defenses webs and associated chemicals might provide (i.e., an aposematic display of unpalatability).

Summers, C. G. (1997). "Phototactic behavior of Bemisia argentifolii (Homoptera: Aleyrodidae) crawlers." Annals of the Entomological Society of America 90(3):372-379.
First instars (crawlers) of Bemisia argentifolii Bellows & Perring were observed in the field and laboratory to move upward on plants, presumably in search of acceptable feeding sites. Laboratory experiments were conducted on a host plant and an artificial surface to determine if this movement was random, or a response to light (phototaxis) or gravity (geotaxis). Greenhouse-reared B. argentifolii crawlers were positively phototactic in experiments conducted on a host plant and on an artificial surface of black construction paper. Crawlers moved up or down the petiole of cheeseweed. Malva parviflora L., with equal facility, toward a light source placed either above or below the leaf blade. Response was always toward the light (positive phototaxis) and there was no response to gravity, either positive or negative. Crawlers placed on an artificial surface in a dark arena and presented with a point light source had a significant mean angular dispersion toward the light. Crawlers illuminated with uniform overhead lighting or kept in darkness moved about the arena at random. Crawlers maintained in darkness on cheeseweed and the artificial surface moved a significantly shorter distance from their origin than did those exposed to light. Such behavior suggests that some minimal light intensity may be necessary to stimulate crawler activity. The positive phototactic response may contribute to survival of B. argentifolii by enabling individuals eclosing from fall laid eggs, on leaves that become senescent during the winter, to find suitable leaves for development higher on the plant.

Sustek, Z. (1999). "Light attraction of carabid beetles and their survival in the city centre." Biologia (Bratislava) 54(5):539-551.
A carabid assemblage attracted on an intensively illuminated advertisement table above a shop window in the centre of Bratislava in August and September 1997 consisted of 40 species. This number was almost the same as in the pitfall trap catches carried out during three growing seasons in 13 sites in Bratislava. Almost 94% of individuals belonged to autumn breeding species inhabiting arable land, while the spring breeders were little represented. Compared with light traps catches performed in other localities by other authors, there was an increased proportion of Amara apricaria. In addition the xerotermophilous species Harpalus tenebrosus and H. zabroides and the rare Polystichus connexus were found. Three major periods in flight activity and species composition of the Carabid assemblage were distinguished according to species abundance and presence. A large number of Pseudoophonus rufipes, P. calceatus, Dolichus halensis and Chlaenius spoliatus colonised the study site. They used various small caves in the walls, gutter pipe outlets or ants' galleries in the sand between pavement and wall bases as an effective cover. The beetles exhibited a surprising ability to survive in the city centre asphalt desert.

Tessmer, J. W., C. L. Meek, et al. (1995). "Circadian patterns of oviposition by necrophilous flies (Diptera: Calliphoridae) in southern Louisiana." Southwestern Entomologist 20(4):439-445.
Circadian ovipositional activities of calliphorid flies on poultry carcasses were assessed during two 24-h periods in mid-summer 1994 during full (July study) and new moon (August study) phases in urban habitats with artificial lighting and in rural habitats without artificial lighting. Immatures of Cochliomyia macellaria (F.) and Phaenicia sericata (Meigen) were the predominant species collected during each of the two 24-h field studies. Flies oviposited during the afternoon diurnal hours and during the morning diurnal period of the following day of the July and August studies. However, egg deposition did not occur on any poultry carcass between the nocturnal hours of 2100 and 0500-h CDST for either study period regardless of the presence or absence of artificial or natural (i.e., full moon) lighting.


This section contributed by Bryant W. Buchanan, Utica College.

Alonso-Gómez, A. L., N. de Pedro, B. Gancedo, M. Alsonso-Bedate, A. I. Valenciano, and M. J. Delgado. 1994. Ontogeny of ocular seratonin N-acetyltransferase activity daily rhythm in four anuran species. General and Comparative Endocrinology 94:357-365.

Bassinger, S. F. and M. T. Matthes. 1980. The effect of long-term constant light on the frog pigment epithelium. Vision Research 20:1143-1149.

Baker, J. 1990. Toad aggregations under street lamps. British Herpetology Society Bulletin 31:26-27.

Beiswenger, R. E. 1977. Diel patterns of aggregative behavior in tadpoles of Bufo americanus, in relation to light and temperature. Ecology 58:98-108.

Besharse, J. C. and P. Witkovsky. 1992. Light-evoked contraction of red absorbing cones in the Xenopus retina is maximally sensitive to green light. Visual Neuroscience 8:243-249.

Binkley, S. K. Mosher, F. Rubin, and B. White. 1988. Xenopus tadpole melanophores are controlled by dark and light and melatonin without influence of time of day. Journal of Pineal Research 5:87-97.

Biswas, M. M., J. Chakraborty, S. Chanda and S. Sanyal. 1978. Effect of continuous light and darkness on the testicular histology of toad (Bufo melanostrictus). Endocrinology Japan 25:177-180.

Buchanan, B. W. 1993a. Effects of enhanced lighting of the behaviour of nocturnal frogs. Animal Behaviour 45:893-899.

Buchanan, B. W. 1999. Low-illumination prey detection by squirrel treefrogs. Journal of Herpetology 32:270-274.

Bush, F. M. 1963. Effects of light and temperature on the gross composition of the toad, Bufo fowleri. Journal of Experimental Zoology 153:1-13.

Chapman, R. M. 1966. Light wavelength and energy preferences of the bullfrog: evidence for color vision. Journal of Comparative and Physiological Psychology 61:429-435.

Cornell, E. A. and J. P. Hailman. 1984. Pupillary responses of two Rana pipiens-complex anuran species. Herpetologica 40:356-366.

Da Silva Nunes, V. 1988. Vocalizations of treefrogs (Smilisca sila) in response to bat predation. Herpetologica 44:8-10.

Delgado, M. J., P. Gutiérrez, and M. Alsonso-Bedate. 1983. Effects of daily melatonin injections on the photoperiodic gonadal response of the female frog Rana ridibunda. Comparative Biochemistry and Physiology 76A:389-392.

D'Istria, M., P. Monteleone, I. Serino, and G. Chieffi. 1994. Seasonal variations in the daily rhythm of melatonin and NAT activity in the Harderian gland, retina, pineal gland, and serum of the green frog, Rana esculenta. General and Comparative Endocrinology 96:6-11.

Donner, K., S. Hemila, and A. Koskelainen. 1998. Light adaptation of cone photoresponses studies at the photoreceptor and ganglion cell levels in the frog retina. Vision Research 38:19-36.

Fain, G. L. 1976. Sensitivity of toad rods: dependence on wave-length and background illumination. Journal of Physiology 261:71-101.

Gancedo, B., A. L. Alonso-Gómez, M. de Pedro, M. J. Delgado, and M. Alonso-Bedate. 1996. Daily changes in thyroid activity in the frog Rana perezi: variation with season. Comparative Biochemistry and Physiology 114C:79-87.

Govardovkii, V. L. and L. V. Zueva, 1974. Spectral sensitivity of the frog eye in the ultraviolet and the visible region. Vision Research 14:1317-1321.

Hartman, J. G. and J. P. Hailman. 1981. Interactions of light intensity, spectral dominance and adaptational state in controlling anuran phototaxis. Zietschrift für Tierpsychologie 56:289-296.

Hailman, J. P. and R. G. Jaeger. 1974. Phototactic responses to spectrally dominant stimuli and use of colour vision by adult anuran amphibians: a comparative survey. Animal Behaviour 22:757-795.

Hailman, J. P. and R.G. Jaeger. 1975. A model of phototaxis and its evaluation with anuran amphibians. Behaviour 56:215-249.

Hailman, J. P. and R. G. Jaeger. 1978. Phototactic responses of anuran amphibians to monochromatic stimuli of equal quantum intensity. Animal Behaviour 26:274-281.

Higginbotham, A. C. 1939. Studies on amphibian activity. I. preliminary report on the rhythmic activity of Bufo americanus Holbrook and Bufo Fowleri Hinckley. Ecology 20:58-70.

Jaeger, R. G. 1981. Foraging in optimum light as a niche dimension for neotropical frogs. National Geographic Society Research Reports 13:297-302.

Jaeger, R. G. and J. P. Hailman. 1971. Two types of phototactic behaviour in anuran amphibians. Nature 230:189-190.

Jaeger, R. G. and J. P. Hailman. 1973. Effects of intensity on the phototactic responses or adult anuran amphibians: a comparative survey. Zeitschrift für Tierpsychologie 33:352-407.

Jaeger, R. G. and J. P. Hailman. 1976. Ontogenetic shift of spectral phototactic preferences in anuran tadpoles. Journal of Comparative and Physiological Psychology 90:930-945.

Jaeger, R. G. and J. P. Hailman. 1976. Phototaxis in anurans: relation between intensity and spectral preferences. Copeia 1976:92-98.

Jameson, D. and A. Roberts. 2000. Responses of young Xenopus laevis tadpoles to light dimming: possible roles for the pineal eye. Journal of Experimental Biology 203:1857-1867.

Joshi, B. N. and K. Udaykumar. 2000. Melatonin counteracts the stimulatory effects of blinding or exposure to red light on reproduction in the skipper frog Rana cyanophlyctis. General and Comparative Endocrinology 118:90-95.

Kicliter, E. and E. J. Goytia. 1995. A comparison of spectral response functions of positive and negative phototaxis in two anuran amphibians, Rana pipiens and Leptodactylus pentadactylus. Neuroscience Letters 185:144-146.

Lee, J. H., C. F. Hung, C. C. Ho, S. H. Chang, Y. S. Lai, and J. G. Chung. 1997. Light-induced changes in frog pineal gland N-acetyltransferase activity. Neurochemistry International 31:533-540.

Mahoney, J. J. and V. H. Hutchison. 1969. Photoperiod acclimation and 24-hour variations in the critical thermal maxima of a tropical and a temperate frog. Oecologia 2:143-161.

Minucci, S., G. C. Baccari, L. DiMatteo, C. Marmorino, M. D'Istria, and G. Chieffi. 1990. Influence of light and temperature on the secretory activity of the Harderian gland of the green frog, Rana esculenta. Comparative Biochemistry and Physiology 95A:249-252.

Morgan, W. W. and S. Mizell. 1971. Daily fluctuations of DNA synthesis in the corneas of Rana pipiens. Comparative Biochemistry and Physiology 40A:487-493.

Morgan, W. W. and S. Mizell. 1971. Diurnal fluctuation in DNA content and DNA synthesis in the dorsal epidermis of Rana pipiens. Comparative Biochemistry and Physiology 38A:591-602.

Muntz, W. R. A. 1962. Effectiveness of different colors of light in releasing positive phototactic behavior of frogs, and a possible function of the retinal projection to the diencephalon. Journal of Neurophysiology 25:712-720.

Pearse, A. S. 1910. The reactions of Amphibians to light. Proceedings of the American Academy of Arts and Sciences 45:159-208.

Rand, A. S., M. E. Bridarolli, L. Dries, and M. J. Ryan. 1997. Light levels influence female choice in Túngara frogs: predation risk assessment? Copeia 1997:447-450.

Riley, C. F. C. 1913. Responses of young toads to light and contact. Journal of Animal Behavior 3:179-214.

Steenhard, B. M. and J. C. Besharse. 2000. Phase shifting the retinal circadian clock: xPer2 mRNA induction by light and dopamine. Journal of Neuroscience 20:8572-8577.

Sustare, B. D. 1977. Characterizing parameters of response to light intensity for six species of frogs. Behavioural Processes 2:101-112.

Tárano, Z. 1998. Cover and ambient light influence nesting preferences of the Túngara frog Physalaemus pustulosus. Copeia 1998:250-251.

Wright, A. H. and A. A. Wright. 1949. Handbook of Frogs and Toads of the United States and Canada. Comstock Publishing Company, Ithaca, NY. pp 167, 169, 188, 314, and 347.

Sea Turtles

Adamany, S. L., M. Salmon, et al. (1997). "Behavior of sea turtles at an urban beach: III. Costs and benefits of nest caging as a management strategy." Florida Scientist 60(4): 239-253.
At a sea turtle nesting beach in Boca Raton, Florida, all nests are covered with a wire cage to protect the eggs from beach traffic and predators. The front panel of the cage (facing the ocean) is of larger mesh that allows hatchlings to escape. In this study we determined if cages impede hatchling migration. No effect was apparent at dark beach sites but at illuminated beach areas, hatchlings crawled toward lights behind the beach rather than toward the ocean, and were trapped within the cage. Trapped turtles eventually escaped, either later that evening (as lighting was reduced toward midnight) or at dawn (as natural levels of background illumination increased). However at night, enough lighting remained to attract turtles after they left the cage. At dawn, escaped hatchlings crawled to the sea but were probably vulnerable to visual predators. We conclude that at urban sites exposed to luminaires, cage use compromises hatchling survival. Thus at urban rookeries, caging is only effective if coupled with efforts to eliminate beach-front lighting.

Peters, A. and K. J. F. Verhoeven (1994). "Impact of artificial lighting on the seaward orientation of hatchling loggerhead turtles." Journal of Herpetology 28(1): 112-114.

Salmon, M., R. Reiners, et al. (1995). "Behavior of loggerhead sea turtles on an urban beach. I. Correlates of nest placement." Journal of Herpetology 29(4): 560-567.
Loggerhead sea turtles nesting in Florida sometimes deposit their clutches on urban beaches. This study was undertaken at a city beach to determine correlations between physical variables and where nests were placed. Over a four year period, the distribution of nests on the beach was statistically identical. Nesting density variation at particular sites was unrelated to offshore depth profiles or to beach width, but was strongly correlated with the presence of tall objects (clusters of mature Australian pine trees and rows of multi-storied condominiums) located between the beach and the city. There are no reports that females nest preferentially in front of tall objects (dune or vegetation) at natural rookeries. The response may be unique to urban rookeries where the nesting habitat is exposed to artificial lighting. Tall buildings and trees shielded the beach from city light, with the magnitude of the effect (and the number of nests) positively related to object elevation. Planting vegetation and reestablishing dunes on urban beaches may be effective methods for attracting nesting turtles to these sites.

Salmon, M., M. G. Tolbert, et al. (1995). "Behavior of loggerhead sea turtles on an urban beach. II. Hatchling orientation." Journal of Herpetology 29(4): 568-576.
At several locations on an urban nesting beach, loggerhead hatchlings emerging from their nests did not orient toward the sea. The cause was city lighting which disrupted normal seafinding behavior. Observations and experiments were conducted to determine why females nested where hatchlings were exposed to illumination, and how hatchlings responded to local conditions. In some cases, females nested late at night after lights were turned off, but hatchlings emerged earlier in the evening when lights were on. In other cases, the beach was shadowed by buildings directly behind the nest, but was exposed to lights from gaps between adjacent buildings. In laboratory tests, "urban silhouettes" (mimicking buildings with light gaps) failed to provide adequate cues for hatchling orientation whereas natural silhouettes (those without light gaps) did. Adding a low light barrier (simulating a dune or dense vegetation) in front of the gaps improved orientation accuracy. The data show that hatchling orientation is a sensitive assay of beach lighting conditions, and that light barriers can make urban beaches safer for emerging hatchlings. At urban beaches where it may be impossible to shield all luminaires, light barriers may be an effective method for protecting turtles.

Salmon, M. and B. E. Witherington (1995). "Artificial lighting and seafinding by loggerhead hatchlings: Evidence for lunar modulation." Copeia 1995(4): 931-938.
Hatchling sea turtles generally emerge from nests at night and crawl immediately toward the ocean ("seafinding orientation"). On natural, dark beaches their orientation is usually appropriate, but where oceanfront buildings are present, hatchlings may crawl toward artificial lighting behind the beach. A systematic survey during the 1993 nesting season documented that, on Florida's beaches, such abnormal behavior ("disrupted orientation") occurred most often on dark nights around new moon and least often under full-moon illumination. Experiments on an urbanized Florida beach (Boca Raton, Palm Beach County) showed that background illumination from the moon, and not an attraction to the moon itself, restored normal seafinding orientation. Background illumination reduced, but did not eliminate, light intensity gradients imposed by artificial lighting. Thus, when seafinding was restored, hatchlings moved toward dimmer, not brighter, horizons. These results suggest that loggerhead hatchlings can locate the sea using mechanisms other than a positive phototaxis (the most widely held view). An alternative hypothesis, supported by these results, is that batchlings locate the ocean by crawling away from objects behind the beach (dune, vegetation, or buildings) using shape and/or elevation cues.

Witherington, B. E. and R. E. Martin (1996). "Understanding, assessing, and resolving light-pollution problems on sea turtle nesting beaches." Florida Marine Research Institute Technical Reports 2: I-IV, 1-73.
Sea turtle populations have suffered worldwide declines, and their recovery largely depends upon our managing the effects of expanding human populations. One of these effects is light pollution - the presence of detrimental artificial light in the environment. Of the many ecological disturbances caused by human beings, light pollution may be among the most manageable. Light pollution on nesting beaches is detrimental to sea turtles because it alters critical nocturnal behaviors, namely, how sea turtles choose nesting sites, how they return to the sea after nesting, and how hatchlings find the sea after emerging from their nests. Both circumstantial observations and experimental evidence show that artificial lighting on beaches tends to deter sea turtles from emerging from the sea to nest. Because of this, effects from artificial lighting are not likely to be revealed by a ratio of nests to false crawls (tracks showing abandoned nesting attempts on the beach). Although there is a tendency for turtles to prefer dark beaches, many do nest on lighted shores, but in doing so, the lives of their hatchlings are jeopardized. This threat comes from the way that artificial lighting disrupts a critical nocturnal behavior of hatchlings - crawling from their nest to the sea. On naturally lighted beaches, hatchlings escaping from nests show an immediate and well-directed orientation toward the water. This robust sea-finding behavior is innate and is guided by light cues that include brightness, shape, and in some species, color. On artificially lighted beaches, hatchlings become misdirected by light sources, leaving them unable to find the water and likely to incur high mortality from dehydration and predators. Hatchlings become misdirected because of their tendency to move in the brightest direction, especially when the brightness of one direction is overwhelmingly greater than the brightness of other directions, conditions that are commonly created by artificial light sources. Artificial lighting on beaches is strongly attractive to hatchlings and can cause hatchlings to move in the wrong direction (misorientation) as well as interfere with their ability to orient in a constant direction (disorientation). Understanding how sea turtles interpret light cues to choose nesting sites and to locate the sea in a variably lighted world has helped conservationists develop ways to identify and minimize problems caused by light pollution. Part of this understanding is of the complexity of lighting conditions on nesting beaches and of the difficulty of measuring light pollution with instrumentation. Thankfully, accurately quantifying light pollution is not necessary to diagnose a potential problem. We offer this simple rule: if light from an artificial source is visible to a person standing anywhere on a beach, then that light is likely to cause problems for the sea turtles that nest there. Because there is no single, measurable level of artificial brightness on nesting beaches that is acceptable for sea turtle conservation, the most effective conservation strategy is simply to use "best available technology" (BAT: a common strategy for reducing other forms of pollution by using the best of the pollution-reduction technologies available) to reduce effects from lighting as much as practicable. Best available technology includes many light-management options that have been used by lighting engineers for decades and others that are unique to protecting sea turtles. To protect sea turtles, light sources can simply be turned off or they can be minimized in number and wattage, repositioned behind structures, shielded, redirected, lowered, or recessed so that their light does not reach the beach. To ensure that lights are on only when needed, timers and motion-detector switches can be installed. Interior lighting can be reduced by moving lamps away from windows, drawing blinds after dark, and tinting windows. To protect sea turtles, artificial lighting need not be prohibited if it can be properly managed.

Other Reptiles

Henderson, R.W., and R. Powell. (2001). "Responses by the West Indian Herpetofauna to human-induced resources." Caribbean Journal of Science 37(1-2): 41-54. Download PDF.

Includes discussion and examples of species that exploit the "night-light niche." See Table 6.

McCoid, M.J., and R.A. Hensley.(1993). "Shifts in activity patterns in lizards." Herpetological Review 24(3): 87-88.

Identifies 8 Anolis species and a skink gathered under porch lights on Cocos Island.

Perry, G. and D.W. Buden (1999). "Ecology behavior and color variation of the green tree skink, Lamprolepis smaragdina (Lacertilla: Scincidae), in Micronesia." Micronesia 31(2): 263-273.

From Results section:

Lamprolepis smaragdina were active during the daylight hours in all locations. At non-lighted sites, and at ones where only diffuse lighting was available at night, we observed no nocturnal behavior. However, up to three skinks were frequently observed at night on the brightly lit trees on the Kolonia campus of the College of Micronesia, Pohnpei. This is the first documented examples of opportunistic night-light feeding in this species. Animals were actively feeding on small insects (mainly microlepidoptera) drawn to the light. Most of these sightings were within two hours of sunset, but at least two of the observations were at about midnight, and several just before dawn. No skinks were observed on any of the adjacent (unlighted) trees at these times, although as many as four were observed together on these same trees during the day.

Schwartz, A. and R.W. Henderson (1991). "Amphibians and reptiles of the West Indies: descriptions, distributions, and Natural history." University of Florida Press, Gainsville.

Coins term "night-light niche" for diurnal lizard species that feed at artificial lights at night.


See annotated bibliography at:

Anonymous (2000). Seatrout vs. Light Nuisance, Scottish Anglers National Association, 

Anonymous (2000). Artificial light influences on Halibut Fishes,

Contor, C. R. and J. S. Griffith (1995). "Nocturnal emergence of juvenile rainbow trout from winter concealment relative to light intensity." Hydrobiologia 299(3):179-183.
This study examined the relationship between light intensity and the number of juvenile rainbow trout (Oncorhynchus mykiss) visible to a snorkeler during February in the Henrys Fork of the Snake River, Idaho, USA. Fish were concealed in the substratum during daylight. Emergence from concealment was observed from 30 to 80 min after real sunset time and began when stars were first visible (pyranometric irradiance, 4.5 times 10-3 W-2). Densities of visible fish were negatively correlated with light intensity (r-2 = 0.81, P < 0.001). Later at night, densities decreased in the presence of moonlight and artificial light. Fish were observed to feed at night.

Croze, O., M. Chanseau, et al. (1999). "Efficiency of a downstream bypass for Atlantic salmon (Salmo salar L.) smolts and fish behaviour at the Camon hydroelectric powerhouse water intake on the Garonne river." Bulletin Francais de la Peche et de la Pisciculture 353-354:121-140.
Three experiments were conducted from 1996 to 1998 at the Camon hydroelectric powerhouse water intake, on the Garonne River, to test the efficiency of a surface downstream bypass for Atlantic salmon smolts. This bypass was built into the trashrack itself at its left edge. The efficiency of the device was evaluated using the mark-recapture method. Smolt behaviour in the intake canal was studied using radiotelemetry technique. In 1996, the bypass efficiency was low (34%). Radio-tracking showed that the bypass location was not responsible for its low efficiency, fish being listened most of the time in the vicinity of the bypass. Nevertheless, an unstable upwelling hided the device entrance. After installing submerged horizontal screen and plates upstream bypass entrance gate, the average efficiency increased to 73%. Good hydraulic conditions in the intake canal and good local hydrodynamic in the vicinity of the bypass entrance are essential to obtain a satisfactory downstream bypass efficiency. Intermittent nocturnal lighting has an effect on smolt behaviour in the intake canal by maintaining fish in directly lighted areas and on the rhythm of fish entry in the bypass, more fish being captured during the first part of the lighting off period. The catching of 7,715 wild salmonids has permitted to study downstream migration rhythms at dam. Daily downstream migration peaks seems to be linked with high water discharge and/or an increase of water temperature. Moreover, downstream migration activity at a dam appears to be mainly nocturnal.

Haymes, G. T., P. H. Patrick, et al. "Attraction of fish to mercury vapor light and its application in a generating station forebay." Internationale Revue der Gesamten Hydrobiologie 69(6): 867-876.
Laboratory and field tests were conducted to determine the effectiveness of filtered mercury vapor lights in attracting fish with possible utilization in a fish conserving scheme at an electrical generating station. In laboratory tests, alewife demonstrated an attraction to the mercury vapor light which was associated with an increase in swimming activity. This response was maintained over a 48 h period. When the filtered mercury vapor lights were utilized in association with a fish pump in the Nanticoke Generating Station forebay, juvenile gizzard shad and smelt were attracted to the pump area. Although there was variation with time of day, turbidity and lighting array, the results suggested that the number of fish passing through the pump increased when the mercury lights alone or when the mercury lights in association with a white strobe light were employed.

Korkosh, V. V. (1992). "Behavior of Atlantic saury and features of its response to light." Voprosy Ikhtiologii 32(4):132-137.
The behavior of Atlantic saury was studied in an artificial light environment. It is found that the response of the fish to light varies during the year and is determined by biological and ecological factors. The effectiveness of attraction of the fish to light depends on the power and spectral characteristics of light sources. A suggestion is made to use xenon bulbs DKST-20,000. It is established that attraction to light in Atlantic saury is based on the food procurement factor.

Larinier, M. and S. Boyer-Bernard (1991). "Downstream migration of smolts and effectiveness of a fish bypass structure at Halsou Hydroelectric Powerhouse on the Nive River." Bulletin Francais de la Peche et de la Pisciculture 321:72-92.
Downstream migration of Atlantic salmon (Salmo salar) smolts in river Nive South-West France was studied in 1987 and 1988 to access the effectiveness of a fish bypass structure at the hydroelectric plant of Halsou. Passage of fish was determined by trapping and video recording. Daily, diurnal and hourly passages at bypass were determined. Tests with marked fish showed between 42% and 95% of the smolts used the surface bypass. Significantly more smolts were bypassed when the discharge was increased. Exploratory tests with halogen and mercury lights were performed. Visual observation indicated that fish was attracted to the lights but avoided the point source: results showed an increased rate of passage when the lamps lighting up the bypass were turned off.

Larinier, M. and S. Boyer-Bernard (1991). "Smolts downstream migration at Poutes Dam on the Allier River: Use of mercury lights to increase the efficiency of a fish bypass structure." Bulletin Francais de la Peche et de la Pisciculture 323:129-148.
Downstream migration of Atlantic salmon (Salmo salar) smolts was studied in 1989 at Poutes dam on the Allier river [France] to evaluate the effectiveness of mercury lights in modifying behavioral responses of smolts at a fish bypass structure. Daily and hourly passage of smolts was accessed by video recording. Migratory activity was mainly nocturnal, diurnal movements increasing at the end of emigration period. Analysis of results showed that the lights significantly increased the rate of passage. Visual observation showed that illumination duration, light location and intensity may be important parameters in effective application of mercury lights for attraction. The effect of lights was not immediate : the maximum passage rate was observed more than half an hour following the activation of lights. Three to eight times as many fish were bypassed with the lights on than with the lights off.

Larinier, M. and S. Boyer-Bernard (1991). "Downstream migration of smolts and effectiveness of a fish bypass structure at Halsou Hydroelectric Powerhouse on the Nive River." Bulletin Francais de la Peche et de la Pisciculture 321:72-92.
Downstream migration of Atlantic salmon (Salmo salar) smolts in river Nive South-West France was studied in 1987 and 1988 to access the effectiveness of a fish bypass structure at the hydroelectric plant of Halsou. Passage of fish was determined by trapping and video recording. Daily, diurnal and hourly passages at bypass were determined. Tests with marked fish showed between 42% and 95% of the smolts used the surface bypass. Significantly more smolts were bypassed when the discharge was increased. Exploratory tests with halogen and mercury lights were performed. Visual observation indicated that fish was attracted to the lights but avoided the point source: results showed an increased rate of passage when the lamps lighting up the bypass were turned off.

Munday, P. L., G. P. Jones, et al. (1998). "Enhancement of recruitment to coral reefs using light-attractors." Bulletin of Marine Science 63(3):581-588.
Methods that enhance larval settlement are required to examine the importance of recruitment in the dynamics of coral reef fish populations. Although it is known that larval reef fishes are attracted to light, here we show for the first time that a light-attraction device positioned above patch reefs at Lizard Island (Great Barrier Reef) significantly increased the number of fish settling on the reefs below. The device was a modified light trap with a tube allowing the vertical movement of larvae from the trap to the reef. The number of species of settling fishes, and the abundance and diversity of immigrant fishes were also greater on the light-enhanced reefs. By comparison, the alternative technique of enhancing recruitment using surface buoys moored to reefs was unsuccessful. Further studies are now required to determine whether enhanced recruitment using light-attractors leads to a longer-term increase in population size, as opposed to temporarily concentrating juveniles on the reef.

Nemeth, R. S. and J. J. Anderson (1992). "Response of juvenile coho and chinook salmon to strobe and mercury vapor lights." North American Journal of Fisheries Management 12(4):684-692.
Species-specific responses to flashing (strobe) and nonflashing (mercury vapor) lights were monitored in hatchery-reared juveniles of coho salmon Oncorhynchus kisutch and chinook salmon O. tshawytscha. Fish behaviors were characterized as attraction and avoidance responses, and as active, passive, and hiding behaviors. We investigated how basic fish behavior and activity changed when fish held under a variety of ambient light conditions were exposed to strobe and mercury light. Implications of how these behaviors may influence migrating smolts at a fish bypass system were discussed. Both chinook and coho salmon avoided strobe and full-intensity mercury light, but chinook salmon exhibited an attraction to dim mercury light. Coho and chinook salmon showed different behavior patterns under most conditions when exposed to strobe and mercury light: coho salmon hid 47% of the time, whereas chinook salmon swam actively 74% of the time. The greatest change produced by either of the stimulus lights was at night when both species normally were passive; exposure to mercury light at nighttime increased fish activity by 90%. Both species also showed similarities in their levels of exictability (e.g., sudden or explosive movements in otherwise sedentary behaviors). The results of this study showed that the behaviors were reproducible: more than 80% of the fish exhibited the same behavior during specific environmental conditions, and sudden and infrequent behaviors were strongly associated with these behavior categories. The behaviors observed in our experimental environment may give insight as to how changes in light relate to fish behavior in bypass systems.

Fritzsche, R.A., R.H. Chamberlain, and R.A. Fisher. 1985. Species profiles: life histories and environmental requirements of coastal fishes and invertebrates (Pacific Southwest) -- California grunion. U.S. Fish Wildl. Serv. Biol. Rep. 82(11.28) U.S. Army Corps of Engineers, TR L-82-4. 12 pp.


"Exposure to light seems to reduce hatching success of grunion eggs (Hubbs 1965). Young grunion are positively phototactic and can be attracted to light as bright as 10,000 lux (Reynolds et al. 1977). The strength of the gathering response is apparently related to the strength of the
light stimulus."

Hubbs, C. 1965. Developmental temperature tolerance and rates of four southern California fishes, Fundulus parvipinnis, Atherinops
, Leuresthes tenuis, and Hypsoblennius sp. California Fish and Game 51(2):113-122.


From abstract: "California killifish eggs hatch more slowly in total darkness while light seems to kill California Grunion eggs."

Reynolds, W. W., D. A. Thompson, and M. E. Casterlin. 1977. Responses of young California grunion, Leuresthes tenuis, gradients of temperature and light. Copeia 1977(1):144-149.


For collision with tall lighted structures see also online bibliography Bird kills at towers and other man-made structures: an annotated partial bibliography (1960-1998)

Avery, M. , Springer, P.F., Cassel, J.F. (1976). "The effects of a tall tower on nocturnal bird migration - A portable ceilometer study." Auk 93:281-291.

Backhurst, G. C. and D. J. Pearson. (1977). "Ethiopian region birds attracted to the lights of Ngulia Safari Lodge, Kenya." Scopus 1(4):98-103.

Baldwin, D.H. (1965). "Enquiry into the mass mortality of nocturnal migrants in Ontario." The Ontario Naturalist 3(1):3-11.

Bergen, F. and M. Abs (1997). "Etho-ecological study of the singing activity of the blue tit (Parus caeruleus), great tit (Parus major) and chaffinch (Fringilla coelebs)." Journal fuer Ornithologie 138(4):451-467.
The main objective of this study was to determine the extent of influence that a large city's ecological conditions have on the singing behaviour of urbanised birds. The singing activity of selected bird species was examined using the "animal focus sampling" method. The observations were carried out from the beginning of March to the beginning of June 1995 in a 10 ha inner city park, the Westpark (WP) in Dortmund (NRW, Germany). An area of equal size in a forest south of Dortmund, the Niederhofer Wald (NW) was chosen as a control area. In the Westpark the Blue Tit, Great Tit and Chaffinch started to sing significantly earlier in the morning than in the control area. This difference could be due to the artificial lighting of the park at night as well as the noise of traffic. There was no difference in the three species' singing activities between the two areas, but there were differences in the temporal pattern of the Chaffinch's morning singing activity in comparison of the two areas. In the Niederhofer Wald the Chaffinch was almost equally active at all times whereas it showed a pattern similar to the Tit's "dawn chorus" in the Westpark. Food supply, distribution and predictability within the two areas are discussed as causes for this difference. However, the negative correlation between singing activity and the frequency of pedestrians crossing the birds' territories may also play a role. In the Westpark, a correlation between the Chaffinch's singing activity and the frequency of passing pedestrians was noted. The more people crossed the focus animal's territory, the less its singing activity and the more frequently "pinks" occurred. Thus, pedestrians do indeed disturb the Chaffinch which reacts with a change of singing behaviour.

Bretherton B.J. (1902). "The destruction of birds by lighthouses." Osprey 1:76-78

Bruderer, B., D. Peter, et al. (1999). "Behaviour of migrating birds exposed to X-band radar and a bright light beam." Journal of Experimental Biology 202(9):1015-1022.
Radar studies on bird migration assume that the transmitted electromagnetic pulses do not alter the behaviour of the birds, in spite of some worrying reports of observed disturbance. This paper shows that, in the case of the X-band radar 'Superfledermaus', no relevant changes in flight behaviour occurred, while a strong light beam provoked important changes. Large sets of routine recordings of nocturnal bird migrants obtained using an X-band tracking radar provided no indication of differing flight behaviour between birds flying at low levels towards the radar, away from it or passing it sideways. Switching the radar transmission on and off, while continuing to track selected bird targets using a passive infrared camera during the switch-off phases of the radar, showed no difference in the birds' behaviour with and without incident radar waves. Tracking single nocturnal migrants while switching on and off a strong searchlight mounted parallel to the radar antenna, however, induced pronounced reactions by the birds: (1) a wide variation of directional shifts averaging 8 degree in the first and 15 degree in the third 10 s interval after switch-on; (2) a mean reduction in flight speed of 2-3 m s-1 (15-30 % of normal air speed); and (3) a slight increase in climbing rate. A calculated index of change declined with distance from the source, suggesting zero reaction beyond approximately 1 km. These results revive existing ideas of using light beams on aircraft to prevent bird strikes and provide arguments against the increasing use of light beams for advertising purposes.

Cochran, W.. W. and R. R. Graber (1958). "Attraction of nocturnal migrants by lights on a television tower." Wilson Bulletin 70(4):378-380.

Derrickson, K. C. (1988). "Variation in repertoire presentation in northern mockingbirds." Condor 90(3):592-606.
Male Northern Mockingbirds (Mimus polyglottos) have exceptionally large vocal repertoires. The manner of presenting this extensive repertoire, as described using five measures, varied with reproductive stage, among situations, and among individuals. All three versatility measures peaked during courtship declined significantly during incubation, and then slowly increased during nestling and fledgling stages. A fourth measure, bout length, increased as the season progressed, being shortest during courtship and longest during the fledgling stage. A final measure, recurrence interval (number of intervening bouts between two bouts of a particular song type) was shorter during the nestling and fledging stages than during courtship. Recurrence interval was shortest during patrolling and countersinging with neighboring males. Over 25% of the song types occurred only once in the sampling of singing behavior of four males each over 2 years. Mockingbirds sang these rare song types most commonly during prefemale and courtship stages, thereby increasing the recurrence interval and versatility during these stages. The pattern just described resulted in the greatest number of song types being sung per unit of time during courtship and provide circumstantial support for the hypothesis that song functions intersexually in mockingbirds. The ability to alter the manner of presentation may provide mockingbirds with the flexibility to emphasize particular functions at certain times and other functions at other times. Males with the highest versatility measures and lowest bout length tended to be the first to acquire mates and begin to nest. However, the importance of versatility in attracting females remains speculative and requires further experimental testing because these results were from only four males. Songs sung at night were presented in a manner most similar to the period before a female arrived on a male's territory. Interestingly, under natural lighting conditions, only unmated males sang extensively at night.

Frey, J. K. (1993). "Nocturnal foraging by Scissor-Tailed Flycatchers under artificial light." Western Birds 24(3):200.

Gorenzel, W. P. and T. P. Salmon (1995). "Characteristics of American Crow urban roosts in California." Journal of Wildlife Management 59(4):638-645.
American crows (Corvus brachyrhynchos) roost in urban areas across the United States creating problems resulting from fecal droppings, noise, and health hazards. With little information about roosts, managers have been unable to respond to questions from the public about roost problems or design control programs. We counted crows flying into Woodland, California, to roost, surveyed roosts for occupancy, and recorded features of 87 roost trees and 62 randomly selected nonroost trees from August 1992 through July 1994. Some crows roosted in town all year, with peak abundance from September through January. Roost trees had greater height, diameter at breast height (dbh), and crown diameter and volume than nonroost trees (P < 0.001 all cases). Most roost trees were located over an asphalt or concrete substrate (P < 0.001) in commercial areas of the city, rather than in residential areas (P < 0.001), and were subjected to greater disturbance from vehicles and people (P < 0.01). Ambient light levels and interior canopy temperatures during winter were greater at roost trees than nonroost trees (P < 0.001 both cases). There were seasonal changes in roost trees selected with an increased (P < 0.001) use of deciduous trees (elms (Ulmus spp.), mulberries (Morus spp.), oaks (Quercus spp.), and ashes (Fraxinus spp.)) in residential areas during summer months as opposed to the concentrated use of evergreen oaks, alders (Alnus spp.), and conifers (Pinus spp. and Sequoia spp.) in commercial areas during winter. We developed a logistic regression model with 4 variables that correctly classified status of 85% of roost or nonroost trees.

Hill, D. 1992. The impact of noise and artificial light on waterfowl behavior: a review and synthesis of available literature. British Trust for Ornithology Research Report No. 61.

Hoetker, H. (1999). "What determines the time-activity budgets of avocets (Recurvirostra avosetta)?" Journal fuer Ornithologie 140(1):57-71.
Time-activity budgets of birds are known to be affected by many different factors. The aim of this study is to explain the intra-specific variation of activity patterns (in particular foraging activity) of one particular wader, the Avocet. Sixty-seven series of scan observations of 12 h to 12.5 h length were made at several sites on the flyway of the northwest European population and at various stages in the species' annual cycle. In estuarine habitats the activity pattern was mainly influenced by the tide. As soon as the conditions allowed (neap tides) Avocets abandoned the tidal rhythm. No time of day effects on activity patterns could be detected. Activity patterns by day and at night were essentially the same, except during very dark nights (owing to artificial illumination at some of the study sites such nights were a rare event), when foraging activity was reduced. The breeding season induced considerable changes of the activity patterns, including a reduction of foraging time to less than 20% of the budget at the end of the breeding season. Outside the breeding season, activity patterns were mainly influenced by the type of food (fish: reduced foraging time, Chironomid larvae: prolonged foraging time), by temperature (increase of foraging time with decreasing temperature), by windspeed (reduction of foraging time at wind speeds above 10 m/s) and by the darkness of the previous night (compensatory feeding after dark nights).

Manville, Albert M., II. (2000). "The ABCs of avoiding bird collisions at communication towers: the next steps." Proceedings of the Avian Interactions Workshop, December 2, 1999, Charleston, SC. Electric Power Research Institute.
Published accounts of avian collisions with tall, lit structures date back in North America to at least 1880. Long-term studies of the impacts of communication towers on birds are more recent, the first having begun in 1955. This paper will review the known and suspected causes of bird collisions with communication towers (e.g., lighting color, light duration, and electromagnetic radiation), assess gaps in our information base, discuss what is being done to fill those gaps, and review the role of the U.S. Fish and Wildlife Service (FWS or Service) in dealing with this important problem. This paper will also review avian vulnerability to collisions with tall structures, currently affecting nearly 350 species of neotropical migratory songbirds that breed in North America in the spring and summer and migrate to the southern United States, the Caribbean, or Latin America during the fall and winter. These species generally migrate at night and appear to be most susceptible to collisions with lit towers when foggy, misty, low-cloud-ceiling conditions occur during their spring and fall migrations. Thrushes, Vireos, and Warblers are the species that seem the most vulnerable. Lit towers, those exceeding 199 feet (61 m) above the ground, currently number about 46,000 in the United States (not including lit "poles"), with the total number of towers registered in the Federal Communications Commission database listed at some 75,000. Also included in this paper are preliminary voluntary recommendations designed to help minimize bird collisions with towers, as well as a review of activities that prompted recent FWS action in dealing with this issue. This paper will further review two partnerships with the electric utility and electric wind generation industries - the Avian Power Line Interaction Committee and the National Wind Coordinating Committee's Avian Subcommittee, respectively - as possible models for a future partnership with the communication industry (i.e., radio, television, cellular, and microwave).

Miller, R. (1998). "Flocks of crows making urban areas home, so look out below." The News-Times, December 28. [online at:].

Negro, J. J., J. Bustamante, et al. (2000). "Noctural activity of Lesser Kestrels under artificial lighting conditions in Seville, Spain." Journal of Raptor Research 34(4):327-329.

Nein, R. "A Robin uses artificial light for feeding at night." Beitraege zur Naturkunde der Wetterau 9(2):213.

Nikolaus, G. 1980. An Experiment to Attract Migrating Birds with Car Headlights in the Chyulu Hills, Kenya. Scopus 4(2):45-46. .

Nikolaus, G. and D.J. Pearson. 1983. Attraction of Nocturnal Migrants to Car Headlights in the Sudan Red Sea Hills. Scopus 7(1):19-20.

Ogden, L. J. E. (1996). Collision course: the hazards of lighted structures and windows to migrating birds. Toronto, World Wildlife Fund Canada and Fatal Light Awareness Program.


Ainley, D. G., R. Podolsky, et al. (1997). "New insights into the status of the Hawaiian Petrel on Kauai." Colonial Waterbirds 20(1):24-30.
We present new information, on the basis of observations and an analysis of existing but unpublished data, regarding the present status of the Hawaiian Petrel on Kauai. A consistently used rafting area just offshore of Hanalei, on the north shore of Kauai, is described for the first time. Observations made there in June and July 1993 and 1994, indicate that the population frequenting breeding colonies, on the order of gt 1000 birds per night during the peak of the visitation cycle, is much larger than previously thought. In contrast, few sightings of this species were made elsewhere around the island. Corroborating these observations were records collected by state and federal biologists on fledglings attracted to lights during their initial flight, 1980-1993, indicating a virtual confinement of the population to the north shore. Data presented also indicate that the nesting season on Kauai maybe a few weeks later than on Maui, the only locale where extensive research has been conducted on this species. On Kauai, increasing numbers of Hawaiian Petrel fledglings are being found each year. We propose that this is a result of the increasing numbers of coastal lights, and not an increase in the petrel's population. The increasing numbers found have implications for conservation of this species' population on Kauai.

Bertram, D. F. (1995). "The roles of introduced rats and commercial fishing in the decline of ancient murrelets on Langara Island, British Columbia." Conservation Biology 9(4): 865-872.
I examined the decline of Ancient Murrelets (Synthliboramphus antiquus), a small, burrow-nesting seabird, at Langara Island. The island's seabird colony was historically one of the largest colonies of Ancient Murrelets in British Columbia-perhaps in the world-with an estimated 200,000 nesting pairs. I reviewed historical information and compared the results of surveys from 1981 and 1988 that employed the same census protocol. The extent of the colony, a potential index of population size, declined from 101 ba in 1981 to 48 ha in 1988. Burrow density increased during the same period, however, suggesting that the colony bad consolidated. In 1988, the population estimate was 24,200 plus-minus 4000 (S.E.) breeding pairs compared to 22,000 plus-minus 3700 in 1981. In 1988, 29% of the burrows that were completely searched contained bones of Ancient Murrelets. Bones were most common in burrows located in abandoned areas of the colony and were least common where burrow occupancy was high. The discovery of adult Ancient Murrelets killed in their burrows by introduced rats, combined with the high proportion of burrows with bone, suggests that rats (Rattus rattus and R. norvegicus) have contributed significantly to the decline of the population. In addition, the presence and activities of a salmon-fishing fleet in the 1950s and 1960s may also be linked to the decline of the Langara Ancient Murrelet population during that period because these fisheries are known to have caused heavy mortality through fatal light attraction and drowning in gill nets. The combined effects of ongoing predation by introduced rats and-to a lesser extent-previous, episodic fishery-induced mortality are probable causes for the population decline.

Lambert, K. (1988). "Nocturnal migration activity of seabirds in the Gulf of Guinea." Beitraege zur Vogelkunde 34(1): 29-35.
The employment of strong light sources aboard of a ship in the Gulf of Guinea in April 1986 allowed insights into the nocturnal migration activity of many seabird-species. Procellariiformes reacted under all weather conditions equally and insignificantly upon the light whereas distant-migrating northern migrants were distinctly stronger attracted in nights with rain and thunderstorm. Most frequent species were Sterna paradisaea, Phalaropus fulicarius and Xema sabini, rarer were Stercorariidae, other Sternidae and others. For Xema and Stercorarius these are the first true records of nocturnal migration. By all these species the daytime was chiefly used for resting and feeding. Sterna fuscata, a tropical species, showed a high daily but a low nocturnal activity.

Le Corre, M., A. Ollivier, et al. (2002). "Light-induced mortality of petrels: A 4-year study from Reunion Island (Indian Ocean)." Biological Conservation 105(1): 93-102.
We report the results of a study of light-induced mortality of petrels at Reunion Island which holds two endemic endangered species, Barau's petrel (Pterodroma baraui) and Mascarene petrel (Pseudobulweria aterrima), together with an endemic non threatened subspecies of Audubon's shearwater (Puffinus lherminieri bailloni). We collected 2348 birds attracted to lights between January 1996 and December 1999, among which 70% were Barau's petrels and 29% were Audubon's shearwaters. We found also three specimens of the very rare Mascarene petrel. Most grounded birds were fledglings (94%). Light-induced mortality was seasonal and linked with the breeding schedule of each species. At least 20-40% of the fledglings of Barau's petrels produced annually are attracted by lights. Light-induced mortality is a recent perturbation at Reunion Island. Thus, the effects of this disturbance on the population dynamics of these long lived seabirds may be hard to detect at the present time, but they are likely to occur in the near future. Conservation actions are proposed to limit the light-induced mortality together with other actions and long-term studies focused on the most endangered species.

Nocera, J. J. and S. W. Kress (1996). "Nocturnal predation on common terns by great black-backed gulls." Colonial Waterbirds 19(2): 277-279.
We observed nocturnal predation by Great Black-backed Gulls (Larus marinus) on eggs and chicks of Common Terns (Sterna hirundo) at a restored tern colony on the coast of southern Maine. Dissection of a nocturnal predatory gull in 1994 revealed two 7d old chicks, 3 embryonic chicks and 5 eggs. Further observations implicating nocturnal predation by gulls on tern eggs in 1995 confirmed that Great Black-backed Gulls can raid tern nesting colonies during moderate to low nocturnal light conditions.

Podolsky, R., D. G. Ainley, et al. (1998). "Mortality of Newell's shearwaters caused by collisions with urban structures on Kauai." Colonial Waterbirds 21(1): 20-34.
We investigated the population ecology of Newell's Shearwaters (Puffinus auricularis newelli) on the island of Kauai, May-November 1993 and 1994. Reported here are (1) mortality rates of adults and subadults caused by collisions with power lines during summer 1993-1994; (2) mortality rates of fledglings as a result of collisions with power lines and other structures in autumn 1993-1994; (3) calibration of adult and fledgling mortality in the data collected by the Save Our Shearwaters (SOS) program, 1987-1994, using the quantified search effort in 1993-1994; and (4) characteristics of power lines that lead to mortality of adults, subadults and fledglings. SOS rehabilitates fledglings grounded after attraction to lights, a phenomenon called 'fallout." Our work was confined to eastern and southern Kauai, where ca. 3,000 shearwater pairs breed. In this area, we estimated that at least 70 breeding adult and 280 subadult shearwaters die each year as a result of collisions with power lines during summer. In the same area, at least 340 fledglings die each autumn. Autumn fallout (and mortality) of fledglings was spread among coastal, urban areas, but summer mortality of adults/subadults was confined, with 74% of deaths occurring at <9% of the coastal power lines (about 7.5 km total). Few adults and no subadults died during autumn. Autumn mortality of fledglings (and fallout in general) increased with greater proximity to bright lights and with the number and (top to bottom) spread of lines in power line arrays. Summer adult/subadult mortality was not correlated to lighting but was correlated to the number and spread of lines, especially where lines were strung across major river valleys. Lack of low vegetation under the lines also increased the number of dead birds found in both seasons. We suggest that in Southern and eastern Kauai, (1) mortality as a result of collisions with power lines is significant; (2) fallout involves fledglings that successfully fly to sea but are then attracted back to land by coastal lights; and (3) a large proportion of adult shearwaters use specific river valley flyways to pass to and from colonies.

Reed, J. R., J. L. Sincock, et al. (1985). "Light attraction in endangered procellariiform birds: Reduction by shielding upward radiation." Auk 102(2): 377-383.
Autumnal attraction to man-made lighting causes heavy mortality in fledgling Hawaiian seabirds: Newell's shearwater (Puffinus auricularis newelli), dark-rumped petrel (Pterodroma phaeopygia sandwichensis), and band-rumpted storm-petrel (Oceanodroma castro). These threatened, endangered and rare species (respectively) approach and circle lights on their first flight from mountain nesting colonies on the island of Kauai [Hawaii, USA] to the sea. Lights of the largest resort were shielded to prevent upward radiation on alternate nights during 2 fledgling seasons. Shielding decreased attraction by nearly 40%. Most attraction occurred 1-4 h after sunset. Full moon dramatically decreased attraction, a phenomenon that has both theoretical and management implications.

Wiese, F. K., W. A. Montevecchi, et al. (2001). "Seabirds at risk around offshore oil platforms in the North-west Atlantic." Marine Pollution Bulletin 42(12): 1285-1290.
Seabirds aggregate around oil drilling platforms and rigs in above average numbers due to night lighting, flaring, food and other visual cues. Bird mortality has been documented due to impact on the structure, oiling and incineration by the flare. The environmental circumstances for offshore hydrocarbon development in North-west Atlantic are unique because of the harsh climate, cold waters and because enormous seabird concentrations inhabit and move through the Grand Banks in autumn (storm-petrels, Oceanodroma spp), winter (dovekies, Alle alle, murres, Uria spp), spring and summer (shearwaters, Puffinus spp). Many species are planktivorous and attracted to artificial light sources. Most of the seabirds in the region are long-distance migrants, and hydrocarbon development in the North-west Atlantic could affect both regional and global breeding populations. Regulators need to take responsibility for these circumstances. It is essential to implement comprehensive, independent arm's length monitoring of potential avian impacts of offshore hydrocarbon platforms in the North-west Atlantic. This should include quantifying and determining the nature, timing and extent of bird mortality caused by these structures. Based on existing evidence of potential impacts of offshore hydrocarbon platforms on seabirds, it is difficult to understand why this has not been, and is not being, systematically implemented.


Beier, P. (1995). "Dispersal of juvenile cougars in fragmented habitat." Journal of Wildlife Management 59(2): 228-237.
There is little information on the spatiotemporal pattern of dispersal of juvenile cougars (Felis concolor) and no data on disperser use of habitat corridors. I investigated dispersal of radio-tagged juvenile cougars (8 M, 1 F) in a California landscape containing 3 corridors (1.5, 4.0, and 6.0 km long) and several habitat peninsulas created by urban growth. Dispersal was usually initiated by the mother abandoning the cub near an edge of her home range. The cub stayed within 300 m of that site for 13-19 days and then dispersed in the direction opposite that taken by the mother. Mean age at dispersal was 18 months (range 13-21 months). Each disperser traveled from its natal range to the farthest part of the urban-wildland edge. Dispersing males occupied a series of small ( <30% the area used by ad M in the same time span), temporary (10-298 days) home ranges, usually near the urban-wildland interface, and often with its longest border along that edge. Each of the 3 corridors was used by 1-3 dispersers, 5 of the 9 dispersers found and successfully used corridors, and 2 dispersers entered but failed to traverse corridors. Dispersing cougars will use corridors that are located along natural travel routes, have ample woody cover, include an under-pass integrated with roadside fencing at high-speed road crossings, lack artificial outdoor lighting, and have <1 dwelling unit/16 ha.

Bird, B., L. C. Branch, and D. L. Miller. (2004). "Effects of coastal lighting on foraging behavior of beach mice." Conservation Biology 18(5):1435–1439.
Introduction of artificial light into wildlife habitat represents a rapidly expanding form of human encroachment, particularly in coastal systems. Light pollution alters the behavior of sea turtles during nesting; therefore, long-wavelength lights—low-pressure sodium vapor and bug lights—that minimize impacts on turtles are required for beach lighting in Florida (U.S.A.). We investigated the effects of these two kinds of lights on the
foraging behavior of Santa Rosa beach mice ( Peromyscus polionotus leucocephalus). We compared patch use and giving-up densities of mice for experimental food patches established along a gradient of artificial light in the field. Mice exploited fewer food patches near both types of artificial light than in areas with little light and harvested fewer seeds within patches near bug lights. Our results show that artificial light affects the behavior
of terrestrial species in coastal areas and that light pollution deserves greater consideration in conservation planning.

Blake, D., A. M. Hutson, et al. (1994). "Use of lamplit roads by foraging bats in southern England." Journal of Zoology 234(3): 453-462.
Roads illuminated by white streetlamps attracted three times more foraging bats (mostly Pipistrellus pipistrellus) than did roads lit by orange streetlamps or unlit roads (3.2, 1.2 and 0.7 bat passes/km, respectively). More insects flew around white lamps than around orange lamps (mean 0.67 and 0.083 insects per lamp, reactively). The mean number of bat passes recorded in any 1-km section of road was positively correlated to the number of white street lamps along the section, and also, independently, to the amount of trees and hedgerows. Bat activity was not related to the number of houses along the road, ambient temperature or cloud cover. The attractive effect of the lamps on the bats was diminished in windy weather.

Gladgelter, H. L. (1966). Nocturnal behavior of White-tailed Deer in the Hatter Creek Enclosure. M.S. thesis, University of Idaho; 63p. WR 231. Project Number: Idaho Cooperative Wildlife Research; IDA. W-085-R-17/JOB 09-PT 1.

Lang, A.B., et al. 2006 (in press). Activity levels of bats and katydids in relation to the lunar cycle. Oecologia. Abstract available at

Passell, H., J.A. Rosenfield, and K.H. Gaines (n.d.). Ecological impacts on ocelot, jaruarundi, and other species, from increased human activity in critical riparian habitat. The Southwest Biodiversity Initiative, Albuquerque, NM.

Rydell, J. (1991). "Seasonal use of illuminated areas by foraging northern bats Eptesicus nilssoni." Holarctic Ecology 14(3): 203-207.
Foraging northern bats Eptesicus nilssoni were monitored from a car along a 27 km line transect in southern Sweden every week during a 14 month period by means of a bat detector. The number of bats observed along the transect was highly correlated with air temperature, and no bats were observed at temperatures < C. Hence, feeding was infrequent in April and May as well as in September and October and did not occur at all from November to March. In summer, the bats were observed in forest and farmland, but in spring and autumn most bats were detected along rows of street-lights. By attracting insects, artificial lights apparently provide local patches of food for some species of bats during periods which may be critical for their survival and reproduction.

Rydell, J., and H.J. Baagoe (1996). Bats & streetlamps. Bats 14(4):10-13. [online at:].

Rydell, J. and H. J. Baagoe (1996). "Street lamps increase bat predation on moths." Entomologisk Tidskrift 117(4): 129-135.
Streets and roads lit by mercury vapour streetlamps provide important feeding habitats for several species of bats, because the lights attract insects, including moths, which thus become easily accessible to the predators. Some common Scandinavian bat species, mostly the northern bat (Eptesicus nilssonii), the particoloured bat (Vespertilio murinus) and the serotine (Eptesicus serotinus), occur at high densities near streetlights (usually 2-5 bats per km, occasionally up to 20 per km). Bats foraging around streetlights catch male moths in large numbers. The effect of the increased predation on the moth populations is unknown. Mercury vapour lights are currently replaced by environmentally more friendly orange sodium lights in many areas. Sodium lamps do not attract insects to the same extent. The replacement will therefore result in decreased food availability for bats that forage near lights (such as those mentioned above). Our threatened bat species seldom feed near streetlights, and will therefore not be affected directly by the replacement.

Sanderson, K. and D. Kirkley (1998). "Yearly activity patterns of bats at Belair National Park in Adelaide, South Australia." Australian Mammalogy 20:369-375.

Svensson, A. M. and J. Rydell (1998). "Mercury vapour lamps interfere with the bat defence of tympanate moths (Operophtera spp.; Geometridae)." Animal Behaviour 55(1): 223-226.
Bats often forage near streetlamps, where they catch moths in particular. At least two hypotheses may explain the apparent increase in the availability of moths to bats feeding around streetlamps: (1) the moths become concentrated near the light and therefore more profitable to exploit; and (2) the light interferes with the moths' evasive flight behaviour. We tested the second of these hypotheses by exposing flying male winter moths, Operophtera spp., to bursts of ultrasound (26 kHz, 110 dB sound pressure level) from an electronic source. The light from a 125 W mercury vapour lamp had a quantitative effect on the moths' evasive flight response at close range (within ca 4 m), inhibiting it totally in nearly half (43%, N = 125) of the cases. By contrast, moths flying in the surrounding woodland and without interference from the lamp always responded to the sound. Streetlamps of the mercury vapour type (white lamps) thus interfere with the defensive behaviour of moths and presumably increase their vulnerability to echolocating bats. This may have implications for the conservation of both moths and bats.


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