News tagged with marine mammal
New study finds dolphins produce sounds in a similar way to humans
(PhysOrg.com) -- It has long been thought that dolphins produce sounds by means of "whistles," but a new analysis of a data gathered in the late 1970s has revealed that instead, dolphins make sounds by means ...
Sep 09, 2011 |
5 / 5 (8) |
2
|
Blainville’s beaked whales go silent at the surface
A new study published in the journal Marine Mammal Science revealed how Blainville’s beaked whales go completely silent in an apparent stealth mode when they near the surface in an effort to avoid predators.
Jul 27, 2011 |
5 / 5 (1) |
0
|
Harvesting of small fish species should be cut: study
(PhysOrg.com) -- New research on the fishing of small fish species near the bottom of their food chains suggests harvesting at levels previously thought to be sustainable could have devastating effects on ...
Jul 22, 2011 |
4.8 / 5 (8) |
5
|
Albatross camera reveals fascinating feeding interaction with killer whale
Scientists from British Antarctic Survey, National Institute of Polar Research, Tokyo, and Hokkaido University, Japan, have recorded the first observations of how albatrosses feed alongside marine mammals ...
Oct 07, 2009 |
4.9 / 5 (7) |
2
Toxic mercury, accumulating in the Arctic, springs from a hidden source
(Phys.org) -- Environmental scientists at Harvard have discovered that the Arctic accumulation of mercury, a toxic element, is caused by both atmospheric forces and the flow of circumpolar rivers that carry ...
Space & Earth / Earth Sciences
May 21, 2012 |
3.7 / 5 (3) |
0
|
Elephant seal tracking reveals hidden lives of deep-diving animals
Researchers at the University of California, Santa Cruz, who pioneered the use of satellite tags to monitor the migrations of elephant seals have compiled one of the largest datasets available for any marine mammal species, ...
May 15, 2012 |
not rated yet |
0
|
Scientists discover way to detect low-level exposure to seafood toxin in marine animals
(Phys.org) -- NOAA scientists and their colleagues have discovered a biological marker in the blood of laboratory zebrafish and marine mammals that shows when they have been repeatedly exposed to low levels of domoic acid, ...
May 03, 2012 |
5 / 5 (3) |
0
|
Calif. rescuers hope dolphin finds way back to sea
(AP) -- A wayward dolphin that has spent two days in a narrow wetlands channel along the southern California coast was on its way out to the ocean Saturday when it suddenly turned tail and swam back to shallow ...
Apr 29, 2012 |
not rated yet |
0
Task force recommends reducing global harvest of 'forage fish'
A task force that conducted one of the most comprehensive analyses of global "forage fish" populations issued its report this week, which strongly recommends implementing more conservative catch limits for these crucial prey ...
Apr 03, 2012 |
3.7 / 5 (3) |
0
|
Multiple species of seacows once coexisted: study
Sirenians, or seacows, are a group of marine mammals that include manatees and dugongs; today, only one species of seacow is found in each world region. Smithsonian scientists have discovered that this was ...
Other Sciences / Archaeology & Fossils
Mar 08, 2012 |
4.2 / 5 (5) |
6
|
Genetic survey of endangered Antarctic blue whales shows surprising diversity
More than 99 percent of Antarctic blue whales were killed by commercial whalers during the 20th century, but the first circumpolar genetic study of these critically endangered whales has found a surprisingly ...
Mar 07, 2012 |
5 / 5 (1) |
0
|
Study examines how diving marine mammals manage decompression
Any diver returning from ocean depths knows about the hazard of decompression sickness (DCS) or "the bends." As the diver ascends and the ocean pressure decreases, gases that were absorbed by the body during ...
Dec 21, 2011 |
5 / 5 (5) |
0
|
Stranded dolphins exhibit bubbles, and ability to recover
Scientists know that the blood and tissues of some deceased beaked whales stranded near naval sonar exercises are riddled with bubbles. It is also well know that human divers can suffer from bubbles-induced ...
Oct 19, 2011 |
5 / 5 (2) |
8
|
Wind farm in North Sea has positive net impact on fauna
A North-Sea wind farm has hardly any negative effects on fauna. At most, a few bird species will avoid such a wind farm. It turns out that a wind farm also provides a new natural habitat for organisms living ...
Technology / Energy & Green Tech
Aug 08, 2011 |
5 / 5 (6) |
0
|
Gray whales likely survived the Ice Ages by changing their diets
(PhysOrg.com) -- Gray whales survived many cycles of global cooling and warming over the past few million years, likely by exploiting a more varied diet than they do today, according to a new study by University ...
Jul 06, 2011 |
4.7 / 5 (3) |
0
|
Marine mammal
Marine mammals are a diverse group of roughly 120 species of mammal that are primarily ocean-dwelling or depend on the ocean for food. They include the cetaceans (whales, dolphins, and porpoises), the sirenians (manatees and dugong), the pinnipeds (true seals, eared seals and walrus), and several otters (the sea otter and marine otter). The polar bear, while not aquatic, is also usually considered a marine mammal because it lives on sea ice for most or all of the year.
Marine mammals evolved from land dwelling ancestors and share several adaptive features for life at sea such as generally large size, hydrodynamic body shapes, modified appendages and various thermoregulatory adaptations. Different species are, however, adapted to marine life to varying degrees. The most fully adapted are the cetaceans and the sirenians, which cannot live on land.
Despite the fact that marine mammals are highly recognizable charismatic megafauna, many populations are vulnerable or endangered due to a history of commercial exploitation for blubber, meat, ivory and fur. Most species are currently protected from commercial exploitation.
For more information about Marine mammal, read the full article at
Wikipedia.
This text uses material from Wikipedia and is available under the GNU Free Documentation License.
