Mediterranean gray whale seen again


This video is called Grey Whale feeding, north of Vargas Island near Tofino.

From the BBC:

Mystery gray whale sighted again off Spain coast

By Matt Walker
Editor, Earth News

A mysterious gray whale sighted off the coast of Israel in the Mediterranean Sea has been seen again off the north east coast of Spain.

The second sighting, made 23 days and 3000km after the first, has continued to perplex whale experts.

Gray whales were thought to be extinct across the Atlantic Ocean, so the appearance of an individual within the Mediterranean Sea was a major surprise.

Now it is not clear where the whale is heading or why.

Once, three major populations of gray (also spelt grey) whale existed: in the western and eastern North Pacific Ocean, and in the North Atlantic.

However, the North Atlantic population of gray whale became extinct sometime in the 17th or 18th Century, for reasons that are not clear.

No sightings of the species had been made in the Atlantic Ocean since.

That was until a single individual gray whale was sighted off the coast of Herzliya Marina, Israel on 9 May this year.

That sighting excited and bemused experts: it could either mean that the gray whale had recolonised the Atlantic Ocean, or that a single gray whale had shattered the record for the longest known migration by the species, which usually make a round trip of 15-20,000km each year.

See also here.

Grey whales took to high seas to survive the ice ages: here.

The epic journey of Gray Whales: The animals travel 18,500km annually in what is one of the longest migrations: here.

Grey Whales Count update: more than 650 thru Santa Barbara Channel: here.

Baja California grey whales: here.

A BBC natural history crew has filmed the “humpback whale heat run”, where 15m long, 40 tonne male whales fight it out to mate with even larger females: here.

Humpback whale off the Isle of Man: here.

IMAGE: Humpback whales eat 3 tons of Krill every day, a tenth of their body weight in tiny invertebrate: here.

Whales closer to us than thought, say scientists: here.

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6 thoughts on “Mediterranean gray whale seen again

  1. A third of young grey whales eaten by killer whales, scientists say

    By Vancouver Sun January 22, 2011

    A group of transient killer whales are killing and eating almost one-third of eastern Pacific grey-whale calves born each year, a groundbreaking four-year study has found.

    The research, conducted by a team of Canadian and U. S scientists, also found the killer whales are storing the carcasses of grey whales in relatively shallow water and returning to feed for several days.

    It is the first time such food-storing behaviour has been documented.

    The killer whales congregate around Unimak Island, Alaska, and for about one month during the grey-whale migration eat grey-whale calves and yearlings almost exclusively, even though the adult greys are much larger than killer whales and their calves are almost as large as the predators, said Lance Barrett-Lennard, Vancouver Aquarium research scientist and one of the study’s authors.

    “The killer whales use a bunch of techniques to separate [grey-whale] mothers from the calves,” he said.

    “The mothers will often defend their calves and, if the mother is very aggressive, the killer whales will give up. The very pugnacious females seem to rule,” he said.

    It is difficult to watch, Barrett-Lennard said, as the grey females try to get the calf to shallow water or try rolling over, nestling the calf in their flippers or on top of them.

    “It’s a real battle to the death and, if the female releases the calf, it’s very one-sided and they kill it very quickly by grabbing it by the snout or the pectoral flipper and pulling it under until it drowns,” Barrett-Lennard said.

    Transient killer whales have previously been seen killing grey whales in Monterey Bay in California and off the west coast of Vancouver Island, but not in the organized fashion or in the quantities documented in the study.

    Grey whales have rebounded from overhunting and the population is now believed to be between 18,000 and 20,000, so the predation is not likely to adversely affect populations, Barrett-Lennard said.

    It is possible other groups of transients are practising similar behaviour, but this group appears isolated and distinct, and have characteristic welts on their bodies, he said.

    The discovery that killer whales are storing the carcasses was unexpected, Barrett-Lennard said.

    Usually, if they kill in deep water, they have only a short time to eat before the carcass drops to the bottom of the ocean, and killer whales are not deep divers.

    “Sometimes they hold up the carcass and get a few more feedings out of it, but it’s very hard work. I had speculated that another way would be to drive [the prey] into shallow areas, but we hadn’t previously seen any evidence of that,” Barrett-Lennard said.

    The researchers found the killer whales would kill greys in depths of 10 to 20 metres and would then leave for 24 hours or more before returning to feed again.

    A spinoff discovery was that killer-whale predation also provides food for Alaskan brown bears and sleeper sharks, and the populations of both are extremely healthy around Unimak Island.

    “Scraps of grey whale wash ashore and the bears are on it in a flash,” Barrett-Lennard said.

    One observation was a whale carcass floating ashore and 19 brown bears immediately gathering around it, he said.

    The research also shows the very specific tastes of different groups of killer whales, Barrett-Lennard said.

    Resident killer whales like chinook salmon and a recent study found offshore killer whales like to eat sleeper sharks.

    © (c) CanWest MediaWorks Publications Inc.

  2. Rare whale swims up West Coast toward Russian home

    By Dan Joling

    3:22 PM Tuesday Mar 20, 2012

    An endangered western Pacific gray whale tracked from Russia to Alaska and along the West Coast to Baja Mexico is on the move again, apparently preparing to cross the Pacific Ocean again.

    The 9-year-old western gray whale dubbed Varvara, the Russian version for Barbara, had passed California, Oregon and Washington and was off northwest Vancouver Island, as of Saturday. She is moving about 160 kilometres per day.

    She is expected to turn left to head back to feeding grounds off Russia’s Sakhalin Island, said Bruce Mate, director of the Marine Mammal Institute at Oregon State University.

    “That’s going to be real exciting soon,” he said by phone. “One of the big questions is, will she retrace the route she came on, or will she take a different route home?”

    If she backtracks, Mate said, she will reinforce scientists’ theory that gray whales learn migration routes from their mothers as they move from a calving area to the mother’s foraging area.

    “But if she takes some other route,” he said, “then we’re going to have to attribute even more navigational skill to her than we’ve done in the past.”

    Varvara and two other western gray whales have already changed what scientists thought they knew about the migration routes, with their deep-water crossing of the Pacific.

    “We used to think of gray whales as near-shore oriented animals in the eastern North Pacific because that’s how they moved along,” Mate said. “It may be that that’s largely an attribute of trying to stay as clear of killer whales as possible. That’s certainly a strategy that mothers with calves use that we see in places where killer whales are abundant moving to shore and defending toward the deep water is easier for moms with calves.”

    Another question that remains unanswered is whether whales off Sakhalin Island are a distinct population from eastern Pacific gray whales or an extension of the range of the latter, Mate said.

    Western Pacific gray whales were hunted, and by the 1970s, were thought to be extinct until a population was spotted off Sakhalin. Just 130 animals remain but they face threats from shipping and offshore petroleum development. Whales have been killed by fishing nets set off Japan.

    In contrast, California gray whales, also called eastern Pacific gray whales, are a recovery success story. Their numbers were decimated by whalers but are now estimated at 18,000. They were taken off the endangered species list in 1994.

    Mate is part of an international research team that includes the National Marine Fisheries Service, the A.N. Severtsov Institute of Ecology and Evolution of the Russian Academy of Sciences, the Kronotsky State Nature Biosphere Reserve and the Kamchatka Branch of the Pacific Institute of Geography.

    The team in September 2010 attached a satellite tag to a 13-year-old male whale named Flex to find out where western grays spend winters. The whale shocked researchers by swimming east across the Bering Sea through Alaska waters and then south off central Oregon, where the tag was lost.

    Researchers last September attached tags to six whales. Four quit working before whales left Sakhalin Island, but in late November, Varvara and another female, named Agent, crossed the Sea of Okhotsk. Traveling separately, they headed east across the Bering Sea toward Alaska, and both crossed the Aleutian Islands into the Gulf of Alaska in late December. Agent’s tag stopped transmitting during the first week of January when she was two-thirds of the way across the gulf.

    Varvara is the first western Pacific gray whale documented all the way to Baja Mexico, where most California gray whales breed and give birth. Scientists know Varvara did not give birth because she would have stayed in one place for four to eight weeks as the calf gained strength.

    She was, however, tracked to all three major breeding and calving areas for eastern gray whales, and she may have found a partner. The whale’s gestation period is about one year.

    “In good years, females are alternately calving and breeding,” Mate said. “Every-other-year-calving is a normal calving interval for healthy adult females when the environment is doing well for them.”

    The satellite tags average 123 days on a gray whale and the longest documented is more than 380 days. Varvara’s has been in place for 200 days. Mate hopes it will last for the crossing of the Pacific.

    The Sea of Okhotsk is frozen and scientists would like to see if Varvara heads for the Kamchatka Peninsula or for waters off Japan to approach Sakhalin Island from the south, Mate said.

    -AP

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