Tag Archives: whales

Bowhead wales survived Ice Age

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This video says about itself:

Join Wild Chronicles on a journey to the Arctic where wildlife filmmaker meets bowhead whale — one of nature’s most long-lived mammals. Not much is known about this mysterious giant, but with a little help from National Geographic’s Crittercam® the filmmaker gets a breathtaking glimpse into the whale’s secret world. The revealing footage has helped researchers discover how these whales can survive centuries in their freezing habitat.

From the BBC:

9 April 2013 Last updated at 16:00

Ice Age bowhead whales‘ survival surprises scientists

By Michelle Warwicker, BBC Nature

Ancient DNA shows that bowhead whales bucked the trend to survive the last Ice Age, say scientists.

The demise of cold-adapted land mammals such as mammoths has been linked to rising temperatures around 11,000 years ago.

But researchers were surprised to find a contrasting population boom for whales living off the coast of Britain.

Their study is also the first to discover that the ocean giants lived in the southern North Sea.

Dr Andy Foote from the Natural History Museum of Denmark, based at the University of Copenhagen co-authored the paper published in the journal Nature Communications.

“Based on all previous studies using ancient DNA to estimate the population size… it seems the trend was for cold-adapted species either [to] go extinct or decline in numbers at the end of the Ice Age as the temperature increased,” said Dr Foote.

But while the fate of now-extinct land-based Ice Age animals is well documented, little has been known about how marine animals were affected by the rapid temperature warming.

Bowhead whales today are found in Arctic seas and rely on sea ice where they feed on tiny crustaceans.

The research team wanted to find out how the whales fared during the rapid climate change of the Pleistocene-Holocene epoch transition when the essential sea ice retreated from their North Sea habitat.

Scientists analysed ancient DNA of partly-fossilised whale remains found in waters between Britain and Holland and around Denmark and Sweden.

They were able to use the data to create a habitat prediction model and build a picture of the whales’ past movements and probability of survival.

On the move

The study showed that bowhead whales shifted their range, moving northwards to more suitable Arctic waters.

“The retreat of the ice in that particular case actually opened up very large areas where you all of a sudden had these ideal habitat conditions for these Arctic species,” said Dr Kristin Kaschner, research affiliate at the University of Freiburg, Germany.

Explaining why these marine animals may have thrived at the end of the last Ice Age while many land mammals populations declined, she added: “Most marine mammals are used to migrating very long distances anyway… I think that’s one of the things that worked in [the whales'] favour, that they were able to track their habitat.”

“And then that combined with the fact that the retreat of ice actually opened up habitat was really favourable for them.”

According to the model, the area of suitable habitat for bowhead whales tripled during the transitional period and the species saw a significant population increase at the same time.

The results show that Ice Age bowhead whales can be genetically identified as belonging to the same population found in the Arctic today, with lineages surviving from the late Pleistocene through to the current Holocene period.

Bowhead whales are thought to be the longest-living mammal in the world, with some individuals possibly even reaching up to 200 years of age.

But the north-eastern Atlantic bowhead whale population is now under threat from intense whaling, according to the researchers.

Their study also suggests that climate change today could present an “additional threat” to the whales. The team estimates that the Arctic animals’ “core suitable habitat” could almost be halved by the end of the century, potentially influencing future populations.

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Antarctic blue whales, new research

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This video is called Worlds Largest Blue Whale colony – Discovered in Sri Lanka.

From Wildlife Extra:

2 Blue whales given satellite tags in the Antarctic

New acoustic devices prove successful for tracking Blue whales

March 2013. A recent research expedition to the Antarctic, using acoustic devices to locate Blue whales, has proved very successful. By using sound rather than sight to initially detect the whales, scientists significantly improved the likelihood of finding and counting whales in the vast Southern Ocean. The research is a core part of an Australian-led international project to estimate the abundance, distribution and behaviour of the species that was decimated in the early 1900s when industrial whaling killed approximately 250,000 animals.

The sonobuoys allowed researchers to record more than 500 hours of audio including more than 20,000 blue whale vocalisations. Two Blue whales were given satellite tags to enable scientists to track their migration, which, it is hoped, will provide vital information on their behaviour and biology.

The 2013 expedition achievements included:

626 hours of acoustic recordings in the sample area; 26,545 calls of Antarctic blue whale were analysed in real time; 43 acoustic groups were targeted, with an 85% success rate.
Identification of 57 individual Antarctic blue whales using photos, plus 11 pygmy blue whales. Identification of 23 individual Antarctic blue whales using biopsy samples, plus 8 humpback whales.
Satellite tags on 2 Antarctic blue whales; both transmitting locations for more than 15 days so far.
100 specimens of Antarctic krill collected for genetics research.

Non-lethal techniques

These statistics do not tell the whole story. Importantly this voyage demonstrated a suite of non-lethal techniques, including acoustic tracking, satellite tagging, photographic and genetic identification, which can be used to study the elusive Antarctic blue whales. The information gathered on this voyage will go towards answering the big question about just how many of these animals remain in the oceans today.

Once the ship has reached New Zealand, the real work begins in analysing the huge data set collected over the past seven weeks.

A spokesman for the crew said “The offices we go back to won’t heave with each wave and the outlook will be less exhilarating, but the work will be equally satisfying and worthwhile. Papers have to be prepared for the International Whaling Commission meeting in Korea in June and the methods, tested and proven on this voyage, will be communicated to our colleagues in the Southern Ocean Research Partnership.”

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Antarctica’s First Whale Skeleton Discovered

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This video from Antarctica is about a minke whale playing with a zodiac.

From ScienceDaily:

Antarctica’s First Whale Skeleton Found With Nine New Deep-Sea Species

Mar. 18, 2013 — Marine biologists have, for the first time, found a whale skeleton on the ocean floor near Antarctica, giving new insights into life in the sea depths. The discovery was made almost a mile below the surface in an undersea crater and includes the find of at least nine new species of deep-sea organisms thriving on the bones.

The research, involving the University of Southampton, Natural History Museum, British Antarctic Survey, National Oceanography Centre (NOC) and Oxford University, is published today in Deep-Sea Research II: Topical Studies in Oceanography.

“The planet’s largest animals are also a part of the ecology of the very deep ocean, providing a rich habitat of food and shelter for deep sea animals for many years after their death,” says Diva Amon, lead author of the paper based at University of Southampton Ocean and Earth Science (which is based at NOC) and the Natural History Museum. “Examining the remains of this southern Minke whale gives insight into how nutrients are recycled in the ocean, which may be a globally important process in our oceans.”

Worldwide, only six natural whale skeletons have ever been found on the seafloor. Scientists have previously studied whale carcasses, known as a ‘whale fall‘, by sinking bones and whole carcasses. Despite large populations of whales in the Antarctic, whale falls have not been studied in this region until now.

“At the moment, the only way to find a whale fall is to navigate right over one with an underwater vehicle,” says co-author Dr Jon Copley of University of Southampton Ocean and Earth Science. Exploring an undersea crater near the South Sandwich Islands gave scientists just that chance encounter. “We were just finishing a dive with the UK’s remotely operated vehicle, Isis, when we glimpsed a row of pale-coloured blocks in the distance, which turned out to be whale vertebrae on the seabed,” continues Dr Copley.

When a whale dies and sinks to the ocean floor, scavengers quickly strip its flesh. Over time, other organisms then colonise the skeleton and gradually use up its remaining nutrients. Bacteria break down the fats stored in whale bones, for example, and in turn provide food for other marine life. Other animals commonly known as zombie worms can also digest whale bone.

“One of the great remaining mysteries of deep ocean biology is how these tiny invertebrates can spread between the isolated habitats these whale carcasses provide on the seafloor,” says co-author Dr Adrian Glover at the Natural History Museum. ‘Our discovery fills important gaps in this knowledge.’

The team surveyed the whale skeleton using high-definition cameras to examine the deep-sea animals living on the bones and collected samples to analyse ashore. Researchers think that the skeleton may have been on the seafloor for several decades. Samples also revealed several new species of deep-sea creatures thriving on the whale’s remains, including a ‘bone-eating zombie worm‘ known as Osedax burrowing into the bones and a new species of isopod crustacean, similar to woodlice, crawling over the skeleton. There were also limpets identical to those living at nearby deep-sea volcanic vents.

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Young minke whale killed by plastic

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The dead young minke whale in Belgium, photo © MUMM/BMM/UGMM

Translated from Ecomare museum, on Texel island in the Netherlands; about Belgium:

Whale killed by plastic – 03.13.13

A young Minke whale washed ashore last weekend on the beach of Nieuwpoort. It was a male, 3.5 meter long and 400 kilogram, so a small one. The whale was still so fresh that researchers believe that the young animal died on the beach. The researchers also discovered why the whale got into trouble ….. there was 400 grams of plastic bags in its stomach.

Constipated

The minke whale was brought for examination to the University of Liège, where veterinarian Thierry Jauniaux went in search of the cause of death. The plastic bags soon gave him a clue. The plastic caused an almost complete obstruction of the digestive tract, causing the animal to be no longer able to feed; finally, starvation killed it. The stranded minke whale was remarkably thin.

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Minke whale beaches in Belgium

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This video is called Swimming with Dwarf Minke Whales (underwater footage).

Translated from Belga news agency today:

Minke whale washed up on the beach of Nieuwpoort

11:23 Early Sunday morning walkers found a beached minke whale on the beach of Nieuwpoort. This is confirmed by the fire brigade of the coastal town.

“It is a minke whale of about 3.5 meters. The animal weighs 400 kilogram. The marine mammal was emaciated, but still intact,” said the fire brigade.

It’s probably a young animal, because adult minke whales can be up to ten meters, while newborns already are about 2.5 meters long. The minke whale is part of the family of baleen whales. “So it is probably a young individual which has strayed,” said the fire brigade.

The dead whale was brought to Gent university for research.

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Sperm whales off Scotland

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This video says about itself:

A baby sperm whale learns to swim alone while its mother hunts deep below.

From Wildlife Extra:

A pod of five sperm whales sighted inshore off North West Scotland

Giants of the sea enjoy Scotland’s warming waters

February 2013. An extraordinary winter sighting of five Sperm whales off the coast of North West Scotland this week could be a reflection of climate change and warming sea temperatures, says a leading marine scientist.

The Sperm whales – one of the true giants of the oceans – were first seen by creel fishermen between Loch Torridon and South Rona on Monday. They initially thought they were Humpback whales and alerted boat operator Nick Davies from Hebridean Whale Cruises, based at Gairloch, who is involved in a project collecting cetacean (whale, dolphin and porpoise) data for Sea Watch.

First sighting

He went out to the location, and when he arrived was astonished to recognise Sperm whales diving together for food – the first time he has ever seen them.

Dr Peter Evans, director of marine conservation research charity Sea Watch, was able to confirm the sighting from his photographs and says: ” In past decades, most records of Sperm whales in British waters have been of lone adult males around Scotland mainly off the Northern Isles and the Hebrides. Increasingly, however, adolescent males have occurred in our waters, sometimes in groups of 5-10 individuals.

Inshore

“Sightings of groups of Sperm whales have tended to occur mainly in summer so this winter sighting of a group is notable not just for the time of year but for its inshore location. The species normally lives in waters of 1,000 metres or more depth, beyond the continental shelf edge. Here they have sought out the deepest area of NW Scotland – the Inner Sound.”

“The increased occurrence of winter sightings in Scottish waters could be a reflection of climate change, with their main prey, squid, becoming more abundant locally in recent years, resulting in animals staying through the winter to feed rather than travelling into lower warmer latitudes.”

Sperm whales

Sperm whales are amongst the largest mammal species in the world. Adult males can weigh in at up to 45 tonnes – the iconic London Routemaster double decker bus weighs less than 8 tons, unladen!

Nick Davies explains: “I was excited at the prospect of Humpback whales, but never expected to see Sperm whales.

“When I was about 8-9 miles away I could see their spouts – it looked like a flotilla of yachts and as I got nearer it was obvious from their flukes (tails), that they were Sperm whales. There was one enormous animal and four smaller ones, and they were synchronised diving, going down for 30 minutes or so at a time.

“Fishermen have been telling me that for the past four or five years they have been seeing increasing amounts of squid in their nets, and it seems that this was perfect for the Sperm whale.”

The sightings, made on Monday February 18th were in waters one mile east of Caol Rona in the Inner Sound between the islands of Rona and Raasay – close to an area where the in-shore waters are at their deepest at 1,000 ft.

Sperm whale ID

Sea Watch is now analysing Nick’s photographs to see if they can be match the tail fluke markings in the trailing edge to any individuals included in a North Atlantic catalogue of individuals photographed from locations as far apart as the Azores and Madeira to Iceland and Norway. Matching of individuals between locations gives us a better idea of the movements of this wide-ranging species. Individuals have already been matched between the Azores and Norway (Andenes and Tromsø). And in 1997, a photo image from Andenes matched a male stranded on the west coast of Ireland.

According to Sea Watch’s national database, there have been just 94 separate sightings in British waters since 1974, with the largest group on record being of 20 animals seen off Mousa in the Shetland Islands in 2007.

Sperm whale facts

Length: Newborn calves are 3.5-4.0m long. Adult females are 8.3-11.0(15.0)m 27.4- 36.3(49.5)ft and can weigh up to 14 tons. Males grow to around 11.0-15.8(20.5) m / 36.3-52.1(67.6) ft (adult male) and can weigh 35-45 tonnes.
Head: The sperm whale has a huge square head (up to one-third total length in male), and under-slung lower jaw.
Fin and Markings: No fin but distinct triangular or dorsal hump two-thirds along body, followed by spinal ridge. Corrugations on skin gives the sperm whale a shrivelled appearance. Dark brown or grey in colour.
ID: The bushy blow of a sperm whale is directed forwards and to left – 1.5-5.0m high; the species may lie log-like on the surface; broad, triangular and deeply notched tail flukes thrown into air.
Lives: up to 70 years.
Feeds: on squid, octopus and other fish.

February 2013. The ships of the Sea Shepherd Society, currently in the southern ocean doing their best to disrupt and halt the Japanese whalers, have clashed with the Japanese whaling factory ship, the Nisshin Maru: here.

Scientists are delving deep into the travels of whales – thanks to high-tech tracking devices – to try to help protect them: here.

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