FAQs

Since the late 1990s, Alaskans have reported large numbers of beak deformities in Black-capped Chickadees and other species of resident birds. This disease, called avian keratin disorder (AKD), is characterized by debilitating beak overgrowth and other abnormalities of keratinized tissues. Affected birds have difficulty feeding and preening, and can suffer high rates of mortality. The USGS has...

Based on the most recent comprehensive survey in 2011, there were about 27,000 glaciers in Alaska. However, the number of glaciers is a misleading statistic. Scientists are more interested in total glacial land coverage as a measure. The number of glaciers is less important since large ones can split up into several as they retreat. The amount of area glaciers occupy in Alaska is trending downward...

Yes, US Topo products are available for all of Alaska. Publication of 1:25,000-scale US Topo maps in Alaska began in 2013. The production schedule is determined by availability of IFSAR elevation data and SPOT imagery provided by the Alaska Statewide Digital Mapping Initiative . To see an index map of publication dates for US Topos in Alaska, go to the National Map Downloader . Put a checkmark...

Determining your risk with regard to earthquakes, or more precisely shaking from earthquakes, isn't as simple as finding the nearest fault. The chances of experiencing shaking from an earthquake and/or having property damage is dependent on many different factors. The National Hazard Maps use all available data to estimate the chances of shaking (of different strengths and frequencies) across the...

Although both are sea waves, a tsunami and a tidal wave are two different and unrelated phenomena. A tidal wave is a shallow water wave caused by the gravitational interactions between the Sun, Moon, and Earth ("tidal wave" was used in earlier times to describe what we now call a tsunami.) A tsunami is an ocean wave triggered by large earthquakes that occur near or under the ocean, volcanic...

Information on the flow of rivers is a vital national asset that safeguards lives, protects property, and ensures adequate water supplies for the future. The USGS is the federal agency responsible for operating a network of about 7,000 streamgages nationwide. Data from this network are used by water managers, emergency responders, utilities, environmental agencies, universities, consulting firms...

Black Brant geese nest in Arctic and sub-Arctic regions of Alaska, Canada, Greenland, Europe, and Russia. Pacific Black Brant --found primarily in Alaska during summer--are a focal species of international attention because of their importance to subsistence and sport hunters and their wide geographic range. Since 1963, surveys have been conducted every fall at Izembek National Wildlife Refuge in...

In 2007, walruses began coming onshore in large numbers on the Alaska coast of the Chukchi Sea, which allowed for more accurate population counts through the use of small aerial drones, satellite tags, and calculations based on walrus behavior. The number of walruses using the U.S. side of the Chukchi Sea in autumn was estimated to be 166,000 in 2018 and 189,000 in 2019. These numbers are...