Only three known species go through menopause: killer whales, short-finned pilot whales, and humans. Two years ago, scientists suggested whales do this to focus their attention on the survival of their families rather than on birthing more offspring. But now this same team reports there’s another—and darker—reason: Older females enter menopause because their eldest daughters begin having calves, leading to fights over resources. The findings might also apply to humans, the scientists say.
How humpback whales use marine habitats off the eastern coast of Africa is only partially understood, and that has become a conservation concern as offshore energy exploration expands in the region. However, a new study published in Marine Ecology Progress Series found that humpback whales that were satellite tagged off the coast of Madagascar during peak breeding season are traveling much further in the southwest Indian Ocean than previously thought. This research can help define potentially sensitive areas that should be protected from the disruption of seismic testing or other industrial development that could be destructive to the humpback population and this globally important marine habitat.
Some beluga whales are adapting to climate change by changing their migratory habits, while other are not, a new study finds. Beluga whales spend the summer in the Beaufort and Chukchi seas, and winters in the warmer Bering Sea to the south. Some beluga whales are delaying their autumn southern migration by up to four weeks, according to a paper published in the journal Global Change Biology.
Pollution in the Arctic is so bad that chemicals are accumulating in polar bear mother's milk and getting passed onto bear cubs. A new analysis of pollutants in the Arctic has found that polar bears are at a particularly high risk, compared to other animals like seals. The study was published in the journal Environmental Toxicology and Chemistry in December and focused on a class of pollutants known as persistent organic pollutants (POPs). POPs are toxic, hang around for a long time, and tend to build up in the bodies of humans and animals.
The vaquita is a small porpoise found only in the northern Gulf of California, in Mexico. Today, the species is critically endangered, with less than 60 animals left in the wild, thanks to fishing nets to catch fish and shrimp for sale in Mexico and America. The animal is an accidental victim of the fishing industry, as are many other marine mammals.
A federal plan for the recovery of an endangered Alaska beluga whale calls for a reduction in threats of high concern while scientists try to pinpoint what has kept the population from growing. The National Oceanic and Atmospheric Administration on Wednesday announced its recovery plan for Cook Inlet beluga whales, a population listed as endangered since 2008.
U.S. Navy-trained dolphins and their handlers will participate in a last-ditch effort to catch, enclose and protect the last few dozen of Mexico's critically endangered vaquita porpoises to save them from extinction. International experts confirmed the participation of the Navy Marine Mammal Program in the effort, which is expected to start sometime this spring.
A sophisticated new type of "tag" on whales that can record data every second for hours, days and weeks at a time provides a view of whale behavior, biology and travels never before possible, scientists from Oregon State University reported in a new study. This "Advanced Dive Behavior," or ADB tag, has allowed researchers to expand their knowledge of whale ecology to areas deep beneath the sea, over thousands of miles of travel, and outline their interaction with the prey they depend upon for food.
Coral in an area in the Atlantic Ocean stretching from Connecticut to Virginia has been protected from deep-sea commercial fishing gear, by a new rule issued this week by the National Oceanic and Atmospheric Administration. The protected area covers some 38,000 square miles of federal waters, NOAA says, which is about the size of Virginia. It's the "largest area in the U.S. Atlantic and Gulf of Mexico protected from a range of destructive fishing gear," according to the NRDC, an environmental advocacy group.
New restrictions on U.S. seafood imports, which will require seafood to be harvested in accordance with the U.S. Marine Mammal Protection Act (MMPA), will likely offer significant marine conservation benefits on a global scale. In this Policy Forum, Rob Williams et al. highlight the impacts and challenges involved in this endeavor. The U.S. is the largest importer of seafood in the world, accepting marine catches from more than 120 countries. Best case scenario, countries will comply and marine species will benefit from improved protection. Worst case, countries could suffer economically from not being able to export to the US, and/or choose not to comply.
An otherworldly noise that was recorded near the Mariana Trench could be a never-before-heard whale call. Dubbed the "Western Pacific Biotwang," this newly discovered call might be from a minke whale — a type of baleen whale — according to the researchers who documented the vocalization. Regardless of what species it is, this whale has range: The call includes sounds that span frequencies that reach as low as 38 hertz and as high as 8,000 hertz. Humans can hear sounds between 20 and 20,000 Hz.
Marine scientists have discovered that two species of dolphin in the waters off Bangladesh are genetically distinct from those in other regions of the Indian and western Pacific Oceans, a finding that supports a growing body of evidence that the Bay of Bengal harbors conditions that drive the evolution of new life forms, according to a new study by the American Museum of Natural History(AMNH), WCS (Wildlife Conservation Society), and the cE3c -- Centre for Ecology, Evolution and Environmental Changes (Universidade de Lisboa).