To our knowledge there are no studies concerning UV-B effects on penguins. As their eyes are exposed to a lot of UV due to the high reflectivity of snow and a marked enhancement during the ozone hole, investigation into the impact on penguins is desirable. The fact that penguins are visual predators, eating krill or fish in the water column, would make any eye damage an important issue for survival.

No. This flightless, aquatic bird is native to the Southern Circumpolar Region, only a short 10,000 miles to the south. See similar questions...

No. Although the wolf survives as an endangered species in a handful of states, from 7,500 to 10,000 wolves populate Alaska — from the most remote wilderness region to the suburbs of our largest cities. Because so much of this state is undeveloped, with more than 160 million acres permanently set aside in protected status (an area larger than California), the wolf is assured of a permanent home in Alaska. See similar questions...

There are many different reasons that animals are endangered, especially loss of their habitat -- where they live, eat, and raise their young. Protecting endangered and threatened species and restoring them to a secure status in the wild is the primary objective of the endangered species program of the U.S. Fish and Wildlife Service, an agency of the Department of the Interior. The Endangered Species Web site can be accessed at <http://www.fws.gov/r9endspp/endspp.html>. See similar questions...

NO! And they never were. In fact, Atlantic Swordfish, previously reported threatened, and after just a few years in quota management, is thriving, replenishing its species stocks to a sustainable level. Meaning- As long as Fisherman are kept to the current limit of harvest, that the species reproduces quickly enough so that their numbers will not deplete, but rather will grow. See similar questions...

No, but one species, C. pelias, is rare within its range. A rigorous ecological study would be required to determine if it's in trouble. See similar questions...

No. Penguins, like all other birds, do not have teeth. The chicks do have an egg tooth, but this is not a real tooth, but rather a sharp bump on the top surface of the bill which is used to break the egg when hatching. Penguins do have rearward-pointing, tooth-like barbs on the tongue and roof of the mouth. These are not used for chewing, but instead assist in the swallowing of their slippery prey. See similar questions...

Yes, penguin ears are in the same place as ours. The only difference is that they have no external ear (the fleshy bit that sticks out the side of your head) and that the opening is covered by feathers. See similar questions...

CI: You would have to be fluent in Penguinese to understand the subtle inflections that differentiate their names. To human ears, they are all named "Waark". See similar questions...

According to one count, 6,703 separate languages were spoken in the world in 1996. Of these, 1000 were spoken in the Americas, 2011 in Africa, 225 in Europe, 2165 in Asia, and 1320 in the Pacific, including Australia. These numbers should be taken with a grain of salt, because our information about many languages is scant or outdated, and it is hard to draw the line between languages and dialects. But most linguists agree that there are well over 5,000 languages in the world. See similar questions...

Although the endangered languages are spoken by minority communities, these communities account for most of the world's languages. See similar questions...

Across their range in Australia they are found in Queensland, New South Wales, Victoria and South Australia and are NOT considered endangered but are listed as vulnerable. However, some local isolated populations of koala could be considered endangered due to habitat loss through housing development. Their food trees are threatened and therefore they could face local extinction. See similar questions...

The following articles will soon be published on this site. If you would like any of them now then email us. Feel free to request these articles for private or student use, with acknowledgment. See similar questions...

Loss of natural roost sites such as trees which, are removed for development, and change of land use, and suitable trees (old ones with holes in) being cut down, for public safety reasons. Caves roosts are often visited by vandals and are used in recreational activities with little or no regard for bats living there. Buildings that bats use are refurbished and modified, sometimes destroying the roost and it's entry. Ignorance is one of the main factors. See similar questions...

To paraphrase Mark Twain, reports of the saguaro's demise are exaggerated! Unfortunately, there have been enough "vanishing saguaro" scares over the years to give many people the wrong idea. Scare number one. About 1940 a plant pathologist reported that many saguaros in Arizona, including a fifth of those in the famous Cactus Forest of Saguaro National Monument, east of Tucson (now part of Saguaro National Park), showed obvious signs of decay. See similar questions...

Hawaii's endangered birds are generally upland birds, because many of them are susceptible to diseases such as bird malaria, which are spread by mosquitos at lower elevations. Many of Hawaii's rarest birds are also dependent on native forest ecosystems, which are today largely restricted to elevations above 2000 feet. See similar questions...

Intensive predator removal efforts from the late-1800s to the mid-1900s extirpated the Mexican wolf from the wild in the portion of its range found in the United States. The Mexican wolf was listed as "endangered" on the Federal List of Threatened and Endangered Species in 1976. Its presence in the wild in Mexico has not been confirmed since 1980. See similar questions...

Florida's burrowing owls are listed as a species of special concern by the Florida Fish & Wildlife Conservation Commission. There are three levels of protection: species of special concern, threatened and endangered. Species of special concern are those facing a moderate risk of extinction in the future. A threatened species is one facing a very high risk of extinction in the future. Endangered species are in imminent danger of extinction due to man-made or natural factors. See similar questions...

According to the International Union for Conservation of Nature and Natural Resources (IUCN), one fifth of all sharks and rays are threatened with extinction. A 2003 study in the journal Science concluded that all shark species, with the exception of makos, had declined by more than 50 percent in the previous eight to 15 years. Hammerheads and thresher sharks declined by as much as 80 percent. See similar questions...