Research Finds How Diving Mammals Evolved Underwater Endurance
by PhysOrg staff
Scientists at the University of Liverpool have shed new light on how diving mammals, such as the sperm whale, have evolved to survive for long periods underwater without breathing.
The team identified a distinctive molecular signature of the oxygen-binding protein myoglobin in the sperm whale and other diving mammals, which allowed them to trace the evolution of the muscle oxygen stores in more than 100 mammalian species, including their fossil ancestors.
Myoglobin, which gives meat its red colour, is present in high concentrations in elite mammalian divers, so high that the muscle is almost black in colour. Until now, however, very little was known about how this molecule is adapted in champion divers…
Enchanting Whale Songs, Stories of a Changing Arctic
by Douglas Main
By tracking and listening to whales, scientists have unlocked secrets about the dramatic changes currently underway in the Arctic. They’ve also learned that these whales are talented singers.
In a wide-ranging talk here at the American Museum of Natural History, researchers and a documentary filmmaker revealed how declining levels of ice have affected the Arctic, as well as the humans that dwell there. Their stories, recounted during a session of the World Science Festival, billed as an annual celebration and exploration of science, reveal the difficulty and beauty of working in the harsh, and quickly changing, environment of the far North…
The Georgia Aquarium wants to import 18 wild-caught Russian beluga whales.
by Kenneth Brower
The Georgia Aquarium is proposing to import 18 white whales, belugas, captured in Russia’s Sea of Okhotsk—three to keep for itself, the rest to distribute to five other marine parks.
This reverses a trend. There have been no imports of wild-caught whales or dolphins into the United States for 20 years. One constraint has been the Marine Mammal Protection Act (MMPA), which requires that captures be humane and not endanger wild populations—a standard that the marine parks find difficult to meet. Another has been a rise in public opposition to whale captivity, a growing PR problem for the industry that may well prove existential.
The beluga proposal, predictably, has ignited controversy. Environmental and animal-rights organizations argue that these 18 wild-caught whales are destined for lives of isolation, sensory deprivation, and mental derangement. The environmentalists suspect that the belugas may just be pump-primers—Trojan whales, in effect—pawns in an industry strategy to resume the interrupted flow of killer whales, the prime moneymakers in marine theme parks…
Scientists still don’t know why hundreds of baby southern right whales are turning up dead around Patagonia, a decade after observers first saw signs of the worst die-off on record for the species, according to the Wildlife Conservation Society (WCS)…
About the size of a large dog, the Hector’s Dolphin is one of the smallest cetaceans, and is the only one endemic to New Zeland.
They prefer shallower waters near the coast, but depending on the season and weather conditions can move to about 25 miles off coast. They feed on almost anything that is about the size they can catch. Hector’s Dolphins are the only dolphin with a rounded dorsal fin. The benefits of this is uncertain.
In less than 50 years, the population of Hector’s Dolphins has decreased by about 85%, leaving less than 7000 in the wild today. Their main threat is over fishing and destruction of their habitat.
Scientists Say Historic Marine Mammal Protection Act Worked
by Megan Gannon
In the fall of 1972, then-President Richard Nixon signed the Marine Mammal Protection Act, providing sweeping protections for whales, dolphins, seals and other species swimming in U.S. waters whose populations had dwindled due to commercial fishing and accidental killing.
The law invigorated conservation efforts and prohibited hunting, killing, capturing and even harassing marine mammals (which we’re reminded of when beachgoers in Florida get caught riding manatees or sickly sperm whales.)
More than 40 years later, a new report shows that the law has been effective: It not only prevented extinctions that seemed imminent, but also helped some species bounce back in strong numbers, researchers say…
Yangtze porpoise down to 1,000 animals as world’s most degraded river may soon claim another extinction
by Jeremy Hance
A survey late last year found that the Yangtze finless porpoise (Neophocaena asiaeorientalis asiaeorientalis) population has been cut in half in just six years. During a 44-day survey, experts estimated 1,000 river porpoises inhabited the river and adjoining lakes, down from around 2,000 in 2006.
The ecology of China’s Yangtze River has been decimated the Three Gorges Dam, ship traffic, pollution, electrofishing, and overfishing, making it arguably the world’s most degraded major river. These environmental tolls have already led to the likely extinction of the Yangtze river dolphin (Lipotes vexillifer), or baiji, and possibly the Chinese paddlefish (Psephurus gladius), which is one of the world’s longest freshwater fish…
New Population of Rare Irrawaddy Dolphins Found in the Philippines
Irrawaddy dolphins found off the coast of the Island Palawan
by Jose Ma. Lorenzo Tan / WWF
April 2013. - A new population of critically-endangered Irrawaddy dolphins has been found in the Philippines by Mavic Matillano of the WWF Palawan team. Spotted by chance off Palawan - along the coastline of the West Philippine Sea - this pod of rare marine mammals, locally called Lampasut, was observed displaying typical behaviour, foraging for prey around lift net fish traps sitting approximately one kilometre offshore.
Previous populations of these dolphins - gifted with features that offer the barest hint of a congenial smile - have been documented in Malampaya Sound, as well as off the island of Panay. The Quezon pod represents the fourth known group of Irrawaddy dolphins reported in the Philippines…