10,000 Walruses Gather on Shore as Ice Retreats
Serguei S. Dukachev, Wikimedia Commons
Tragedies like the Boston Marathon bombings remind us how important first responders are. Animals come to the rescue of members of their own species too.
Dolphins, for example, form "living rafts" to keep ill or injured dolphins buoyant, according to a paper published in Marine Mammal Science. Up to 12 dolphins, working together in a pod, may swim together to try and keep one of their own afloat.
Meerkats have one of the animal kingdom's most efficient security operations. A sentinel stands guard, watching for any potential threats. Should an intruder approach, an entire clan -- from elderly grandmas to younger dads -- mob the unwelcome visitor.
"Non-dangerous terrestrial animals most often ran away when they were approached and mobbed by the meerkats," explained Beke Graw and Marta Manser of the University of Zurich. More threatening animals, such as poisonous snakes, were also mobbed, but the meerkats often had to back down and leave, knowing they might be safer doing so.
Charles J. Sharp, Wikimedia Commons
Risking their own lives, vervet monkeys make loud alarm calls when they spot a predator, saving others from harm. According to Robert Seyfarth of the University of Pennsylvania and colleagues, the monkeys even identify, the specific type of predator in the loud calls.
"Animals on the ground respond to leopard alarms by running into trees, to eagle alarms by looking up, and to snake alarms by looking down," the researchers explained.
U.S. Department of the Interior
American bison are formidable animals, both in terms of size and weight, so they are usually only taken down by large predators, such as mountain lions, wolves and humans. According to Animal Diversity Web, bison travel in lines led by dominant adults. If they detect a predator, a meaningful bison-emitted grunt or snort tells the herd to be wary. Mother bison, as for many animal moms, will also fight to the death to save their young.
John Verive, Flickr
Male wild chimpanzees living in Bossou, Guinea, have figured out how to deactivate, and sometimes even destroy, snares set out by human hunters, according to Gaku Ohashi of the Japan Monkey Center and colleagues. The researchers documented instances where the chimps set free trapped individuals and took steps to deactivate snares, such as by shaking or hitting the devices.
Vampire bats starve to death if they do not feast on a blood meal after two nights. Roost-mates come to the rescue during famines, according to biology Gerald Wilkinson of the University of Maryland. "A buddy system ensures that food distribution among the bats is equitable," he explained. Bats seem to have BFFs with whom they regularly share blood meals via regurgitating. Barfing up blood may be a stomach churner for humans, but for these bats, it's a lifesaver.
Dave Otee, Flickr
Ants, well known for their complex societies, put the preservation of the overall colony above their individual needs. They identify colony members by scent, according to Gregg Henderson and colleagues from the USDA. Intruders who literally stink -- not matching the colony's signature scent -- will be attacked with as much force as an ant can muster.
Captain Budd Christman, NOAA
Walruses breed during harsh Arctic winters, with mothers giving birth to just one offspring per season. If disaster strikes and the infant becomes an orphan, another walrus female may adopt it, according to The Encyclopedia of Earth. Communal care of young by multiple female walruses has also been documented.
Alvesgaspar, Wikimedia Commons
There are many accounts of cats saving members of their own species and humans. One example of the former was Scarlett, a calico owned by Karen Weller of New York. When Scarlett and her litter of five kittens became trapped in a Brooklyn garage fire, the mother feline carried out each of her kittens to safety. During the five separate trips, Scarlett sustained severe burns to her eyes, ears and face, but she forged ahead until all kittens were out of danger.
In fiction, Lassie came to the rescue of seemingly everyone and everything. Fiction in this case mirrors fact, as there are countless reports of heroic dogs saving the day. A video on Animal Planet, for example, (http://animal.discovery.com/tv-shows/weird-true-and-freaky/videos/dog-rescues-dog-on-highway.htm) captured footage of a dog in Santiago, Chile, pulling another injured dog to safety. This first responder canine had to navigate through heavy traffic, but the brave dog managed to pull off a happy ending
If you see a walrus in the wild, chances are you’ll see other walruses with it. A lot of other walruses. And it doesn’t matter if the ice floe that they have chosen as the spot on which to rest is seemingly far too small to accommodate such a massive quantity of blubber and tusk: Like a Great Dane that doesn’t know it isn’t supposed to be a lap dog, they will somehow squeeze their collective bulk onto it. It can be, candidly, an amusing sight: a floating platform of ice barely visible beneath a mound of giant pinnipeds.
The strategy is not without its risks: Walruses can be spooked, and sometimes it only takes one of the throng to twitch in response to some anticipated danger for the rest of the crowd to hurtle into the water — leaving pups in particular of being crushed beneath the tumult.
But there is method in such evident madness. For one, the potential risk is outweighed by the doctrine of safety in numbers, and the fact that so many walruses in one place provides protection against polar bears. But the reason they seek out ice floes in the first place is not only to rest, but also because they need a platform from which to dive to the shallow seabed and feast on the clams, snails, worms and other benthic animals that are their preferred prey.
However, as is well known, Arctic sea ice is diminishing in extent — and, in places such as the north of Alaska, is retreating farther from the shore over summer. That means that instead of being over the shallow areas of the continental shelf, it is now in deeper waters, too deep for walruses to repeatedly make dives. And so instead, they swim back to shore, where they gather in massive haulouts. Scientists with the National Oceanic and Atmospheric Administration (NOAA) have documented just such a haulout on a barrier island near the village of Point Lay in northwest Alaska. Using aerial photographs, scientists estimated that the area initially contained 1,500 to 4,000 animals on Sept. 12. The number of walruses had increased to 5,500-8,000 when sighted on Sept. 22, and on Sept. 27, biologists estimated that there were approximately 10,000 walruses. (Awesome zoomable photograph here).
Such massive haulouts are a recent occurrence in the region, as NOAA noted in a press release:
The first large beach haulout in this region formed in 2007 near Pt. Lay, coinciding with an unprecedented loss of sea ice across the Chukchi Sea. Subsequent haulouts formed in northwestern Alaska near Icy Cape and Cape Lisburne in 2009, and near Pt. Lay in 2010, 2011 and 2013. During 2008 and 2012, remnants of sea ice offshore in the Chukchi Sea were sufficient for walruses to rest on between foraging bouts.
The U.S. Fish and Wildlife Service notes that increased reliance on such vast shore-based haulouts run the risk of exposing “all individuals, but especially calves, juveniles, and females, to increased levels of stress from depletion of prey, increased energetic costs to obtain prey, trampling injuries and mortalities, and predation.”
Photo: Government scientists spy a massive walrus gathering in northwest Alaska. Credit: NOAA