Ecological Light Pollution founded
September 1, 1999

The Environment does not go away when darkness falls!

This IS the environment
This is the Environment!
From  Venus by the Lake Credit & Copyright: Tunc Tezel

This page is inspired by Catherine Rich and Travis Longcore of The Urban Wildlands Group

A new page is under construction relating to the connection of Light Pollution to the decline of Salmon in California.
Vanishing California Salmon

Portion of this page relating to Human Health have been moved to a  new page.
Light At Night (LAN) and Health
in addition look for a new page titled  

Ecological Light Pollution
The Urban Wildlands Group is dedicated to the conservation of species, habitats, and ecological processes in urban and urbanizing areas.
Link To
Ecological Consequences of Artificial Night Lighting - Conference (ECANLC 2002)
Link To
"Ecological Light Pollution" in Frontiers in Ecology and the Environment (.pdf 300k)
Get File
Vincent Thomas Bridge, San Pedro - activities relating to lighting the bridge
Link To
"Ecological Consequences of Artificial Night Lighting is an excellent reference that will undoubtedly raise awareness of the need to conserve energy, do proper impact assessments, and turn down the lights."       -David Hill in Science
Link To
Ecological Consequences of Artificial Night Lighting By Catherine Rich, Travis Longcore is now on Google Book Search
Link To
Ecological Consequences of Artificial Night Lighting By Catherine Rich, Travis Longcore is now at the

Sacramento Public Library under Call Number 577.272 E19 2006
Link To
Environmental Effects of Light Pollution,
Link To
Photobiology and Pathology,
Link To
Natural Night Preserves, a local page that addresses astronomy and light pollution in our State and National Parks.  .
Dark Sky Parks and Preserves , at
Stone Lakes NWR Partnerships ( a good source for local Orginizations )
Habitat Conservation
Sacramento Valley Conservancy, SVC's mission is to preserve the beauty, character and diversity of the Sacramento Valley landscape ...
The Conservation Planning Program is responsible for statewide oversight of various approaches used to balance the needs of threatened, endangered, and sensitive species and habitats with the needs of land users.
The Institute for Ecological Health  The Institute for Ecological Health facilitates harmony between human communities and their natural ecosystems. We link the conservation of rural landscapes and a viable agricultural economy to the conservation and enhancement of wildlife habitat, native biodiversity and ecological functions.
Cosumnes River Preserve - The Cosumnes River Preserve encompasses and protects thousands of acres of wetlands and adjacent uplands. The Cosumnes River Preserve is recognized as one of California's most significant natural areas.
Cosumnes River Preserve Management Plan - DRAFT
Notes: The Management Plan now contains the following language.
2.1.4  As new development projects proposed around the Preserve, ...  ensure that project proponents to consider potential effects on visual resources at the Preserve, including the effects of outdoor nighttime lighting.
2.2.1  Prior to installing new outdoor lighting for the Preserve, the lighting shall be reviewed to ensure consistency with Objective 1.2.

The Endangered Species Act (ESA) and it's relation to Outdoor Lighting
Could the effects of Outdoor Lighting constitute a "taking" under the ESA?
The answer is, without question YES!    
see the following
Loggerhead Turtle v. County Council of Volusia County, Florida, 148 F.3d 1231 (11th Cir. 1998).
Loggerhead Turtle v. County Council of Volusia County, Florida, 896 F. Supp. 1170 (M.D. Fla. 1995).

Could a city along a water way fall under this act if it's docks, and river front cast light onto the water?
If lighting increases predation of a listed species, then the municipality must  be authorized accidental takes of the subjec species.
"Harm" includes "significant habitat modification or degradation where it actually kills or injures wildlife by significantly impairing essential behavioral patterns, including breeding, feeding, or sheltering."

National Wildlife Refuge System Notes
601 FW 3 Biological Integrity, Diversity, and Environmental Health
C. Environmental Health.
(3) At the population and community levels, we consider the habitat components of food, water, cover, and space. Food and water may become contaminated with chemicals that are not naturally present. Activities such as logging and mining or structures such as buildings and fences may modify security or thermal cover. Unnatural noise and light pollution may also compromise migration and reproduction patterns. Unnatural physical structures, including buildings, communication towers, reservoirs, and other infrastructure, may displace space or may be obstacles to wildlife migration. Refuge facility construction and maintenance projects necessary to accomplish refuge purpose(s) should be designed to minimize their impacts on the environmental health of the refuge.
Media Coverage

Recent story in Sacramento Bee
The salmon lovers return to Old Sac,  By Lisa Heyamoto -  November 27, 2007
If you've been hanging around Old Sac these days, that barking you hear isn't the coyotes fighting for a piece of the nearby downtown railyard.
Nope, it's a pack of vocal sea lions – a rookery, if you will, because apparently I'm obsessed with collective animal nouns.
About this time each year, the marine mammals travel to our bend in the river in pursuit of the savory salmon run, conveniently congregating near the Delta King.   Manager Mike Coyne says it makes for a pretty spectacular spectacle for paddleboat passengers.
"What's kind of fun is when they're right off the boat and they're fishing," he said.
In case you didn't know, the difference between sea lions and seals is all in the ears – as in, sea lions have them and seals don't.
As for what they end up deciding about that railyard, we're all, all ears.
**  What Lisa and others don't understand is that the lighting around the Delta King and Docks are why the salmon are easy picking for the sea lions.  It is wall documented that predation increases in areas with lighting along rivers during salmon runs and during out migration.
We in this quote form
Ecological Consequences of Artificial Night Lighting Page 266 provide just one documented example.
"Lights along a migratory watercourse may allow increased predation by other vertebrate predators.
Both inmigrating adult and outmigrating juvenile salmon are captured by mammalian and avian predators, which can exert a significant pressure on depressed fish populations (Yurk and Trites 2000).   On the Puntledge River in British Columbia, Canada, lights from a bridge, halogen lights from a recreational field, and halogen lights from a sawmill facilitated foraging on outmigrating smolts by harbor seals (Phoca vitulina; Yurk and Trites 2000).
A "lights-out" experimental treatment at the bridge reduced the number of seals feeding, but on subsequent nights the seals repositioned  to exploit illumination from residual urban light."
Search note [seals salmon  preditation  +lighting  +bridge] [seals salmon  predation  +lighting  +bridge]

Seeing stars is simple as turning down the lights  , Local light pollution activist works to further stargazing and fight energy waste.
By Blair Anthony Robertson - Bee Staff Writer  August 27, 2007

Study: Harsh Lighting May Damage Embryos, San Jose Mercury News - Aug 14, 2007
"Sunlight and cool-white fluorescent lights caused the most damage to mice embryos in the study, even when exposure was limited to a few minutes, said Dr. Ryuzo Yanagimachi, a retired University of Hawaii researcher known for his expertise in reproductive biology."
Cool-white fluorescents, which are blue-white in appearance, are commonly used in office environments.
Warm-white lights, which are yellow-white in color and popular in residential settings, resulted in "far more" eggs developing into babies, Yanagimachi said.
"We found that warm-white light is less damaging," Yanagimachi said.  ...

"People do not pay much attention to light as a negative environmental factor," he said.

Related Links -
Study: Harsh Lighting May Damage Embryos,
Study: Harsh Lighting May Damage Embryos, Las Vegas SUN
Study: Harsh Lighting May Damage Embryos,
Bright Lights May Damage Embryos,
Bright Lights May Damage Embryos, Discovery Channel:: News - Health
Study: Harsh Lighting May Damage Embryos, First Coast News Health
Study: Harsh Lighting May Damage Embryos,
Study: Harsh Lighting May Damage Embryos,
Study: Harsh Lighting May Damage Embryos,

More links - Google search "lighting may damage embryos" -- about 24,300 hits.

Lights out on Britain's bats, The Observer by  Juliette Jowit and Robin McKie Sunday July 15, 2007
As more buildings are lit up at night, bats are in trouble - because they need darkness to feed. Now campaigners are stepping in to help them.
Britain's inky nights are disappearing - and with them their most famous inhabitant, the bat. Researchers have found that growing light pollution is now playing havoc with the country's flying mammals.
Related Links -
Vision in Echolocating Bats, The aim of this thesis is to investigate the use of vision by echolocating bats.
Impact of outdoor lighting on man and nature (.pdf)

Scientists Discuss Possible Dangers of Nighttime Light Kansas City infoZine, MO - Feb 23, 2007
Are the streetlights and security lights the Western world takes for granted causing breast cancer, killing sea turtles and blocking views of the constellations? ...
More than 100 scientists, lighting technicians and government workers registered for the two-day conference hosted by the Carnegie Institution, a non-profit research center. ...
Urban Glow Hides Stars, Disrupts Animal Life Men's News Daily, CA - Feb 22, 2007
Astronomers, whose view of the heavens is being dimmed, are complaining, but biologists are also decrying light pollution because they find it hurts ...
Bright Nights Dim Survival Chances Science Now, DC - Feb 22, 2007
At a conference here yesterday, researchers reported that even low levels of light from incandescent, fluorescent, or other humanmade sources can befuddle creatures that require a period of nighttime darkness. The findings add to the evidence that artificial lighting is interfering with the development, reproduction, and survival of species across the taxonomic spectrum. ...
Urban Glow Hides Stars, Disrupts Animal Life Voice of America -Feb 22, 2007
As populations and cities grow, our once pristine view of the stars is being whitewashed by urban glow.  Astronomers, whose view of the heavens is being dimmed, are complaining, but biologists are also decrying light pollution because they find it hurts wildlife development and possibly human health, too. ...
Astronomers, whose view of the heavens is being dimmed, are complaining, but biologists are also decrying light pollution because they find it hurts ...
Bright Nights  Texas Parks and Wildlfe magazine,  June 2006
Bright Lights, June 2006 issue of Texas Parks & Wildlife Magazine  (print page)
From fireflies to ocelots, many species are adversely affected by ever-increasing levels of artificial lighting.  " The insects clearly pay a dear price, in the form of increased predation by the opportunistic spiders and geckos. That may seem like a good thing, until you consider the importance of bugs as food for animals and pollinators for plants. For example, says Mike Salmon, a biologist at Florida Atlantic University, reduced insect populations force many birds to work much harder to find enough insects to feed their young."

Subject List ( Quick Links ) for this page

Amphibians  |  Birds  |  Fish  | Invertebrates - Aquatic -- Terrestrial

Rodents  |  Reptiles  |  Plants  |  Sea Turtles  |  News & Events


"The periodicity and duration of light and darkness is powerfully important in the development of many plants. The measurement by plants of light/dark periodicity enables them to fit their growth patterns to the seasons, and the duration of periodic darkness is critical for the onset of flowering in many higher plants. Thus, relatively strong light pollution during the night (as from street or flood lights) may seriously disturb the normal growth, development, flowering and senescence patterns of sensitive plants."
-- Roger G.S. (Tony) Bidwell, Ph.D, “ECOLOGY OF THE NIGHT” Symposium, September 22-24, 2003

Invertebrates - Aquatic

As many as 90% of the living things in our lakes and rivers are found
along their shallow margins and shores.
"The implications are far reaching and could ultimately link light pollution to water quality. Minute zooplankton lurk well below the surface during the day to avoid predators, then rise to graze on algae at night. But artificial light discourages them from venturing toward the surface. “If their grazing is inhibited . . . effects will cascade up the food chain,” Moore says."
-- Ben Harder, Degraded Darkness, Conservation In Practice, Spring 2004 Vol 5 no. 2

Invertebrates - Terrestrial

Insects are attracted to the light, it is believed that in an attempt to keep the same portion of their eyes illuminated by the light they either spiral into the light or around it continuously.   Insects can see from 300-400 nm (near ultraviolet) to 600-650 nm (orange).  There are two peaks in wavelength activity, one at about 350 nm (near ultraviolet) and another at about 500 nm (blue-green).  It is believed that insects react to the ultraviolet wavelengths because ultraviolet light is absorbed by much of nature, especially by the green foliage.

Presentations relating to Terrestrial Invertebrates at ECANLC 2002

Prof. Dr. Gerhard Eisenbeis, presenter at ECANLC 2002
From A note on Assam  (references to "destruction crickets, months and other insects")    (link down)

Possible role of eclosion rhythm in mediating the effects of light-dark environments on pre-adult development in Drosophila melanogaster   (link down)

Insects of the World Senses and Communication Eyes and Vision    (link down)

Guide to Bertha Armyworm Monitoring  ( warning about lights)    (link down)

USDA Systematic Entomology Laboratory

Collecting and Preserving Insects and Mites: Techniques and Tools - light traps - USDA-SEL

ALS Beginners Guide to Moth Trapping 

Sleep in Insects from The World Federation of Sleep Research Societies   (link down)

Effects of Gravity on Insect Circadian Rhythmicity   (link down)

American Burying Beetle 

"Causes of Decline: The cause for the decline of this species is not clearly understood. Declines could be a result of habitat fragmentation, habitat loss, carcass limitation, pesticides, disease, light pollution, or a combination of these factors. Species experts believe the primary cause of decline habitat loss and fragmentation."...    Reference --
Salt Creek Tiger Beetle
..."With only three populations of Salt Creek Tiger beetles remaining, this property is vital to protecting known populations from light pollution and water quality impacts while allowing for expansion of occupied habitat to ensure against catastrophic events.  The property will be managed in perpetuity for the beetle.  This property will also provide additional habitat for two imperiled bird species - the least tern and piping plover."...
Reference --

Marine Life - Amphibians

As many as 90% of the living things in our lakes and rivers are found
along their shallow margins and shores.

When the researchers and three of their students switched on the lights at sunset one evening, the nocturnal salamanders responded with the amphibian equivalent of pulling the covers over their heads. They waited an hour longer than usual to get up for breakfast. ... Does a later start for the salamanders mean fewer nightly meals and fewer calories? Does that cut into their fertility or increase their mortality? What does it mean for the insects that the salamanders eat and for the predators that, in turn, eat them? Wise doesn’t yet have answers.
-- Ben Harder, Degraded Darkness, Conservation In Practice, Spring 2004 Vol 5 no. 2

"An unobscured full moon provides about 0.3 lux. ... Squirrel tree frogs (Hyla squirella), by contrast, can see well enough to navigate and forage at 0.0001 lux or less, and they avoid activity when illumination exceeds 0.001 lux. Other frog species favor even darker conditions."
-- Ben Harder, Degraded Darkness, Conservation In Practice, Spring 2004 Vol 5 no. 2

"Most amphibians have evolved activity patterns and sensory capabilities that allow them to forage and interact socially under low-illumination conditions. Thus, artificial night lighting has the potential to disrupt normal activity and behaviour of nocturnal amphibians."
-- Bryant W. Buchanan, Ph.D.  “ECOLOGY OF THE NIGHT” Symposium, September 22-24, 2003.

California Tiger Salamander

The Santa Rosa Plain Conservation Strategy, selected references to  lighting and the California tiger salamander (CTS).
"Minimization measures would be employed in design and construction of projects in or adjacent to conservation areas to reduce impacts to CTS, listed plants, wetlands, and hydrology of the surrounding areas. Design-related minimization measures could include construction during the dry season, passageways/under-crossings for CTS, curbing to exclude CTS from harmful areas, lighting designed to minimize off-road ground illumination, retaining the hydrologic characteristics of the surrounding area and avoiding breeding habitat. Construction-related minimization measures are shown in Section 5.2." ...
"Studies have shown that lighting can negatively impact CTS, so roads within conservation areas or along conservation area boundaries that include lighting systems should be designed to direct the lighting to the roadway with minimal illumination of the surrounding area (Longcore and Rich, 2004). Where roads are constructed or widened, it is encouraged that they be properly designed; therefore, a reduced CTS mitigation ratio of 1:1 will be allowed for road projects in reaches designated on Figures 3 through 12 that meet the following criteria:
• Constructed with exclusionary curbing along both sides of road for the total length of roadway, and passageways/under-crossings for CTS located no more than 200 feet apart
• Include lighting designed to minimize off-road ground illumination
..."    Reference --


Bright Lights, June 2006 issue of Texas Parks & Wildlife Magazine -  Nocturnal frogs suspend normal feeding and reproductive behavior when exposed to light, and individual hoppers may remain motionless long after the light is turned off. Female frogs of at least one species are less selective about a mate in increased levels of light — call it the closing time effect — presumably balancing the need to be choosy against the equally important need to survive. Male tree frogs have been known to stop calling in areas with bright lights, and no calling means no mating, which eventually means no frogs.

Marine Life - Fish


Related link - Vanishing Sacramento River Salmon  and Pinniped Predation and Lighting (on this site)

Electronic deterrent for hungry harbour seals - "Seals wait in those shadows until they see juvenile salmon pass by in the lights overhead and then snatch them for a quick and frequent meal.  The ease with which the seals are able to kill the salmon due to the lighting in that area are making it very difficult for the fish produced at the hatchery on the Puntledge River to make it out to sea." 


IMPACTS OF FERRY TERMINALS ON JUVENILE SALMON MIGRATING ALONG ...  "Dock lighting is also observed to induce temporary/localized delays by attracting fish, especially at nighttime. This is perhaps associated with prey attraction and/or visibility of prey." ... "Delayed migration of salmonids seems to happen when fish are confronted with conflicts regarding their preferences for eelgrass, dark areas, night lighting, or turbid zones."
With the exception of brief comments provided by Andrew Clarke of the Environment Agency, there appears to be little information regarding the potential effects of lighting on fish. Enquiries to clarify the lighting levels at which fish may be affected, have been
unsuccessful. The only practical comparator level is that produced by moonlight, which is generally accepted to be approximately 0.3-lux. However, it must be appreciated that this 0.3-lux level will be spread evenly over a large area of the river, and it is understood that problems arise where a bright band of light is present across a river, effectively forming a barrier through which fish may not pass. This is the typical effect produced by bridge mounted lighting, as demonstrated by the lighting design calculations. In order to minimise this effect, it will be necessary to restrict spill lighting to the bridge deck, by fitment of shields, or reduce the spill lighting levels on the river, to that produced by moonlight.

NOAA Fisheries Headquarters - marine fisheries program home page (*)

Light Nuisance - Stonehaven & District Angling Association Case  " In 1998, Stonehaven & District Angling Association secured a landmark UK court judgement on Light Nuisance (aka light pollution) which has attracted widespread interest from groups as diverse as biologists, civic societies, astronomers and others alarmed about the intrusive impact of ever-increasing artificial light sources on the natural environment and on the wellbeing of the individual. It is of particular importance to game anglers."
"This expert evidence revealed that seatrout, in common with most other nocturnal creatures, only night-adapt into an active roving and feeding role when natural light falls to between 0.5 and 0.2 Lux, owing "inter alia" to greater risk of predation at higher illuminance levels. There is also a concurrent switch from colour (cone) vision to black-and-white (rod) vision. The importance of this low illuminance underlines the widely held opinion amongst experienced seatrout anglers, that an unshaded full moon (around 0.3 - 0.2 Lux) is highly ominous to fishing success."

Effects of Artificial Light on Deep Sea Organisms  , "Extensive studies concerning morphology of deep sea fish and crustacean eyes demonstrate a wide variety of adaptations to life in near-darkness. In fishes, such adaptations include gross changes in eye anatomy (Marshall 1979), as well as increased retinal photoreceptor sizes (Munk 1966) and increased levels of visual pigment (Denton and Warren, 1957). Several species of crustaceans exhibit analogous adaptations, including depth-related increases in rhabdom length and crystalline cone dimensions (review in Land, 1981; Hiller-Adams and Case, 1984), This combination of characteristics provides high light sensitivity required for low-light vision; however, it may also make them more susceptible to damage from bright light."
"Numerous studies of deep sea fishes and crustaceans have demonstrated that most of these organisms contain retinal photopigments with peak sensitivities between 450 and 500 nm; roughly similar to the spectra of downwelling light and bioluminescent emissions (Denys and Brown, 1982; Frank and Case, 1988; Hiller-Adams et. al., 1988; Partridge et. al., 1988 ). "

Potential Impacts of Shoreline Development - City of Bellevue WA  search  [Potential Impacts of Shoreline Development]
"Pier lighting may facilitate nocturnal predation on juvenile chinook and coho salmon by visual predators like smallmouth bass, cutthroat trout, and piscivorous
"Shoreline development could potentially increase the rate of predation on juvenile chinook by several principal means: ...
4) providing artificial lighting that allows for around-the-clock foraging by predators; "
"extending the duration of predation by allowing visual predators to forage at night (piers with artificial lighting)."
"Alteration (slowing) of migratory behavior and subsequent increased sculpin predation rates on sockeye fry with increasing light intensity were observed in simulated stream experiments (Tabor et al. 1998)."
"14. Artificial lighting retards migratory progress of sockeye fry, subjecting them to increased predation. Lights from industrial areas in south Lake Washington facilitate nocturnal foraging by piscivorous birds."
"13. Do not permit shoreline or pier lighting unless future studies suggest otherwise."

The use of cage lighting to reduce plasma melatonin in Atlantic salmon (Salmo salar) and its effects on the inhibition of grilsing -  "The effects of additional night time illumination on circulating plasma melatonin levels and maturation were studied in Atlantic salmon maintained in sea cages under commercial conditions. Salmon subjected to additional night-time lighting from November to July had significantly lower dark phase melatonin levels (303.1±6.3 pg/ml) compared to control fish (600.0±53.0 pg/ml) maintained under ambient photoperiod. More importantly, as far as the commercial farmer is concerned, only 6.1% of the group exposed to additional lighting matured compared to 61.5% of the fish in the control group. It is suggested that the clear effect of the additional lights on reducing grilsing in Atlantic salmon is mediated through a reduction in the amplitude of plasma melatonin below a putative threshold level during the subjective dark phase."

Effect of photoperiod manipulation on the daily rhythms of melatonin and reproductive hormones in caged European sea bass (Dicentrarchus labrax) (.pdf)
"Exposure to light at night suppressed circulating melatonin when fish were exposed near the surface as well as near the bottom (5m deep) of the cage. This result points out the effectiveness of the artificial lights used in the experiment, such as light intensity and also spectrum, which have been shown to be of great importance  (Bayarri et al., 2002; Porter et al., 1999, 2000)."
"As regards to daily melatonin rhythms, our results in both groups agree with the nocturnal profile reported in other teleosts, with low values under light conditions and high values under darkness, being the nocturnal rise as long as the dark period (Bromage et al., 2001)"

The Control of the Timing of Seasonal Reproduction in Salmonid Fish (link down)

Photoperiodic Control of Smoltification in Atlantic Salmon (link down)
Photoperiodic Mechanisms and the Control of Fish Reproduction (link down)
Light influences Atlantic halibut (link down)
Floodlights so disrupted the night-adaptation and subsequent behavior of the sea trout (link down)

Two ways to advance spawning in broodstock salmon - "Salmon take their cues to mature by photoperiod. Photoperiod refers to the amount of daylight relative to darkness in a 24 hour period. After the winter equinox, the daylight hours increase relative to darkness. At the spring equinox, the rate of change from dark to light reaches a maximum. After the summer equinox, the process reverses itself and daylight hours begin to shorten. These rates of change influence maturation in salmonids."

A fish's sense of sight   (link down)
The Endangered Species Act and the Salmon Listings   (link down)
Coagulated Yolk   (link down)
FISH HATCHERY OPERATION and Light   (link down)

1998 Greater Seattle Chamber of Commerce Leadership Conference

Marine Life - Sea Turtles 

"Artificial lighting has had profound negative effects on nesting behavior and success." (

At the loggerhead turtle nesting grounds in Florida, says turtle researcher Michael Salmon of Florida Atlantic University, “the problem is fast becoming not the amount of light at the beach but rather sky glow from inland.” Salmon argues that the growing threat to darkness must be attacked at its source—population centers. “Nothing covers that,” he says, “except having a national policy that governs how lighting is used everywhere.”
-- Ben Harder, Degraded Darkness, Conservation In Practice, Spring 2004 Vol 5 no. 2


Turtles Win at Eleventh Circuit,   Water Log 18.4  University of Mississippi -   The Eleventh Circuit ruled that the county's incidental take permit does not authorize it to take protected sea turtles through artificial beachfront lighting because the lighting is solely a mitigatory measure.  ...


"Nocturnal snake species are thinning out more rapidly than diurnal snake species, even in areas where development isn’t cutting directly into snake habitat."
-- Ben Harder, Degraded Darkness, Conservation In Practice, Spring 2004 Vol 5 no. 2

Avian (Birds)

"On some mornings since that day in 1988, Mesure and an army of volunteers have identified more than 1,000 birds that had perished in this way during the previous night. The Fatal Light Awareness Program targets tenants in downtown Toronto’s high-rises, and it advocates the use of window shades or blinds and directed task lighting at workstations, as well as switching off lights in unused areas at night."
-- Ben Harder, Degraded Darkness, Conservation In Practice, Spring 2004 Vol 5 no. 2




Bright Lights, June 2006 issue of Texas Parks & Wildlife Magazine - All 986 species of bats in the world are nocturnal, equipped to do best in low light. Populations in rural areas like Devil’s Sinkhole or Old Tunnel Wildlife Management Area still enjoy those conditions, and lights may actually be beneficial for urban populations, attracting insects for the bats to eat. But bright lights have been known to stop emergence of the bats under Congress Avenue bridge in Austin, says Barbara French, a scientist with Bat Conservation International. And faster-flying bat species that congregate around lights to take advantage of the insect buffet may displace slower-flying species that avoid lights and the increased predation danger they represent.

Completion of Heysham to M6 Link: - Planning Application 2005  Lune Bridge section 6.1 Street Lighting Impact Assessment  Lancashire County Council, UK
An enquiry with the Bat Conservation Trust has confirmed that the whole of the Lune area is one of the most important sites for Bats in North Lancashire. There are several important Daubentons Bat (Myotis Daubentonii) colonies along the River Lune corridor, some of which are very close to the proposed bridge location. There are also known colonies of Noctule and Brown Long Eared Bats together with populations of other Myotis species (Whiskered/Brandts and Natterers) and both species of Pipestrelle (p.Pipistrellus and p.Pygmaeus). The Bat Conservation Trust provided an information leaflet entitled Impact of Lighting on Bats (which is based on a document produced by Dr Jenny Jones – May 2000). This leaflet details how artificial lighting can affect the feeding  behaviour of bats. Studies have shown that while certain species of Bats, such as Leislers, Serotine and Pipistrelle, will swarm around White Mercury type lighting, feeding on insects, this behaviour is not true for all Bat species. The slower flying broad winged species, such as Plecotus, Myotis and Rhinolophus, avoid streetlights. It is believed that both the Plecotus and Myotis shun bright lights as a predator avoidance strategy. It is claimed that lighting can be particularly harmful if used along river corridors, near woodland edges and hedgerows used by Bats. Studies have shown that continuous lighting along roads creates barriers, which some Bats cannot cross, for example Daubentons Bats, which move their flight paths to avoid street lighting. As stated above, it is understood that there are several colonies of Myotis species in this vicinity, and it may be prudent to undertake further consultations with the Bat Conservation Trust, in view of the protected status of Bats.

Sonoran pronghorn


Light at Night (LAN) and Human Health

11 FEB  2009
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