Amphibians are highly sensitive to light
and can perceive increases in illumination that are impossible for humans to
detect (Hailman and Jaeger). A rapid increase in illumination causes a
temporary reduction in visual acuity, from which the recovery time may be
minutes to hours. In this manner, a simple flash of headlights can arrest
activity of a frog for hours. Frogs in an experimental enclosure ceased mating
activity during night football games when lights from a nearby stadium
increased sky glow.
Artificial light
interferes with the production of the hormone melatonin, which is involved in
regulating many important functions, including sexual development,
thermoregulation, adaptation of eyes to the dark, and skin coloration. Current
research shows that artificial lighting slows larval amphibian development in
the laboratory. (Fig.2)
According to a report published by the
American Medical Association, artificial lighting should try to reduce the
amount of amphibian ecosystem disruption by adjusting the artificial lighting
at night, especially streetlights, below 3000K.
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