Ultraviolet Light and Its Role in Predation in Fish. How Fool-a-Fish Was Discovered. By Milan Jeckle M. D. Citat: "...So in summary, I was reading quality scientific research articles that were reporting that ultraviolet [UVA] traveled through [klart] water at least 700 feet [ca. 230 meter] and maybe as much as 2,500 feet [ca. 800 meter] before it was absorbed, unlike visible light which is completely absorbed in the first 40 feet [ca. 12 meter]...The result was the scientific recognition that bony fish and birds have a Rodopsin protein in their retinas which reacts to the ultraviolet wavelengths around 360 nm, a wavelength totally invisible to humans. We also discovered that insects, shrimp and crabs have similar keen ultraviolet vision..."
October 17, 2003, ScienceDaily: Bats Scan The Rainforest With UV-Eyes Citat: "...Bats from Central and South American that live on the nectar from flowers can see ultraviolet light...Flower visiting bats seem to need UV-vision, because the flowers they visit in the rainforest are characterised by a strong reflection of UV-spectrum light at night. It remains open whether the unusually high UV-sensitivity found in these bats involves a further photo-mechanism that is as yet unknown for mammals..."
Amphibians and Ultraviolet Radiation Citat: "...The more DOC [Disolved Organic Carbon], the less UVB that will penetrate beyond just the upper surface layers of water. For example, in a marsh with 13 mg C per liter of water, the surface level of UVB was reduced to 55% at just 1.4 cm deep; at 3.0 cm, the UVB was less than 5% of surface values, and at 5 cm depth, the UVB was just 2% of surface..."