As their name suggests, spiny dogfish sharks (Squalus acanthias) have sharp spines in front of each dorsal fin. Their bodies are dark gray above and white below, often with white spotting on the sides. They are marketed as "rock shark", "rock cod" or "rock salmon" and are often eaten in Europe and used for English fish and chips. This...
Salmon sharks (Lamna ditropis) are large, powerful, warm-bodied (endothermic), and streamlined predators adapted for high-speed swimming. Reports from the U.S. Navy have clocked salmon sharks exceeding 50 knots. This would make the salmon shark one of the fastest fish in the ocean. They are reported to reach 11.9 feet (3.6 m) in total length (Eschmeyer et al. 1983, Compagno...
Pacific sleeper sharks (Somniosus pacificus) range from the Chukchi Sea, East Siberian and Beaufort seas, to the Bering Sea and in the Pacific Ocean to Baja California and off Japan including the Okhotsk Sea. Closely related to the Greenland shark (Somniosus microcephalus), it is one of the few sharks found in polar waters year-round. Noted for its lethargic nature,...
As large carnivores, Alaska brown bears range over great expanses of land, sometimes as much as 150 square miles for a single bear. In addition, brown bears depend upon such land features and associated animals and plants as alpine, slopes, sedge meadows, salmon streams, and old growth forests. These areas satisfy seasonal needs for feeding, winter denning, raising cubs,...
Ocean Acidification Bad for Shells and Reefs
Rising levels of atmospheric carbon due to fossil fuel emissions have made seawater more acidic. Now, two new studies show that increasing acidification could wreak havoc on marine organisms that build their shells and skeletons from calcium carbonate. Since these creatures provide essential food and habitat for other ocean dwellers, the effects could...
The 1985 report of the discovery of an "ozone hole" over Antarctica focused attention on the idea that humans can have a significant impact on the global environment. This discovery, along with evidence that ozone is being lost at nearly all latitudes outside the tropics, has prompted much research into the causes of ozone depletion and the biological effects...
Some scientists warn growing levels of human-caused noise in the oceans from military sonar, ships, oil exploration and drilling, offshore construction, motor boats, and jetskis is disrupting and/or killing whales, dolphins, and other marine life. In 2001, 16 whales and a dolphin were stranded on the northern coast of the Bahamas. Six of the whales and the dolphin died;...
Bald eagles (Haliaeetus leucocephalus) are a member of the Accipitridae family, which also includes hawks, kites, and old-world vultures. Scientists loosely divide eagles into four groups based on their physical characteristics and behavior. The bald eagle is a sea or fish eagle.
The adults have a blackish-brown back and breast; a white head, neck, and tail; and yellow feet and...
Marine debris and litter has become both a significant coastal and open ocean problem. Considerable portions of this debris is made of persistent synthetic materials such as plastics, and is not biodegradable as past product waste has been. Surveys have indicated that nearly 80 percent of marine debris originates from land-based activities.
The increasing influx of people into coastal zones...
Although only a small percentage of oil enters the ocean from major oil spills, it is from studies during those events that we understand the extreme toxicity oil has on marine animals. A smaller spill at the wrong time/wrong season and in a sensitive environment may prove much more harmful than a larger spill at another time of the...