Bowhead whales

No, they don’t need to take showers! Bowhead whales apparently have the ability to sniff the air!

This discovery could drastically change our theories on how baleen whales find their food, as researchers now have a sneaking suspicion that the bowhead whales actually sniff out swarms of krill, their main food source.

This discovery was made when scientists hacked open the body of a bowhead whale and noticed that there was olfactory receptors which linked to the nose and the brain.

Up until now, it was thought that whales, along with dolphins, had no sense of smell.

Professor Hans Thewissen, a Cetacean expert from the Northeastern Ohio Universities College of Medicine, and colleagues based in Alaska and Japan, stumbled upon this discovery while taking a gander at the size of the brain in bowhead whales.

The whales were reeled in as a part of the biannual Inupiat subsistence hunt, and Professor Thewissen’s team was granted permission to take a gander at the brain cavities, to figure out how much of the brain actually filled up the brain casing.

“Upon taking a brain out, I noticed that there were olfactory tracts, which, in other mammals, connect the brain to the nose,” Professor Thewissen explained, “I followed those to the nose, and noted that all the olfactory hardware is there.”

This really caught the scientists off guard.

“At first glance, it would appear that whales would not have much use for smell, since everything they are interested in is below the water,” Professor Thewissen explained, “Olfaction is, by definition, the reception of airborne molecules.”

He went on to explain that in most cetacean species which have been put under the microscope to date, which have mainly been whales with teeth like dolphins, sperm whales and orcas, the hardware needed for them to be able to smell was absent.
“Based on this most people assumed that no whale had a sense of smell.”

With a little more digging and prodding, and some extensive tests, it was confirmed that the discovery that the bowhead can indeed smell, is accurate.

Bowhead whales exhibit a large and developed olfactory bulb, which seems to be very similar in structure to the hardware other animals have which can also smell.

It was also discovered by researchers that the bowheads also have functional olfactory receptor proteins, and this is one quality that toothed whales are lacking. These receptors are what provide the biochemical infrastructure for them to be able to smell.
“It is remarkable that this animal, which appears to have very little use for olfaction, retained that sense,” Professor Thewissen said. “We speculate that they are actually able to smell krill and may use this to locate their prey. Krill smells like boiled cabbage.”

Also, unlike most other species of whale, the bowhead actually have separate nostrils, which leads scientists to think that they may be able to not only smell, but determine from which direction the smell is coming.

I guess this means the next time you go bowhead whale watching, remember to wear your deodorant.

Most IWC* member countries accidently kill whales, e.g. by unintentionally ramming into them with motorized vessels or by using fishing methods that may entangle and suffocate these air-breathing mammals as accidental by-catch. While this type of accidental deaths is reported from most member nations, Japan and South Korea have an inordinate amount of accidental by-catchs, says Professor Scott Baker, associate director of the Marine Mammal Institute at Oregon State University.

By analysing the DNA of whale-meat products sold in Japanese markets, Baker, a cetacean expert, and Dr Vimoksalehi Lukoscheck of the University of California-Irvine, found that meat from as many as 150 whales came from the coastal population. Japan’s scientific whaling program only targets whales from open ocean populations, but whales accidently killed outside the program are allowed to be sold.

Humpback Whale

Japan and South Korea are the only countries that allow the commercial sale of products derived from whales killed as accidental by-catch and the sheer number of whales represented by whale-meat products on the market suggests that there might be something fishy about these allegedly accidental kills.

They DNA study showed that nearly 46 percent of examined Minke whale products came from a coastal whale population, which has distinct genetic characteristics, and is protected by international agreements. In addition to minke whales, Baker and Lukoscheck also found DNA from Humpback whales, Bryde’s whales, Fin whales, and Western gray whales.

“The sale of bycatch alone supports a lucrative trade in whale meat at markets in some Korean coastal cities, where the wholesale price of an adult minke whale can reach as high as $100,000,” Baker said. “Given these financial incentives, you have to wonder how many of these whales are, in fact, killed intentionally.”

In January 2008, Korean police launched an investigation into organized illegal whaling in the port town of Ulsan, reportedly seizing 50 tons of minke whale meat.

Japan has asked the IWC, who is holding its annual meeting this week, to allow a small coastal whaling program in Japanese waters. This request is something that professor Baker says should be scrutinized carefully because of the uncertainty of the actual catch and the need to determine appropriate population counts to sustain the distinct stocks.

Baker and Lukoscheck have presented their findings to the IWC commission and the study will also be published in a forthcoming issue of the journal Animal Conservation.

* International Whaling Commission

Australia and New Zealand announced Thursday that they will carry out a six-week long non-lethal whale research expedition in the Antarctic early next year. Dubbing the expedition non-lethal is a direct challenge to Japan’s research program that kills up to 1,000 whales a year.

Iceland and Norway are the only two countries openly defying the IWC ban on commercial whaling; Japan is instead using a lope whole that allows for “lethal research”. Whale meat resulting from the Japanese research is sold for human consumption and many critics claim that this is the real motive behind the program.

In a joint statement, Australia and New Zealand announced their intentions to reform science management within the International Whaling Commission, which holds its annual meeting in Madeira, Portugal, next week, and end Japan’s “so-called scientific whaling.”

“This expedition and the ongoing research program will demonstrate to the world that we do not need to kill whales to study and understand them,” said Australian Environment Minister Peter Garrett.

The expedition aims to increase our knowledge of population structures, abundance, trends, distribution, and the ecological role of whales in the Southern Ocean.

During the latest Japanese hunt, which ended in April, 679 minke whales and one fin whale was killed over a period of five months.

Bottle nosed dolphins living along the coast of Florida are getting used to supplement their diet by snatching bait from fishing lines or circle recreational anglers practising catch-and-release. Some dolphins have even made a habit out of routinely approaching humans to beg for food.

Scientists at the National Marine Fisheries Service have now been able to show that this behaviour is spread down through generations of dolphins.

“We are able to document lineage, from grandmother to mother to calf, all following fishing boats and taking thrown-back fish,” says Jessica Powell, a National Marine Fisheries Service biologist.

Dolphins begging for food might be an endearing sight, but approaching humans in this fashion means taking a great risk. In 2006, three dead Sarasota Bay dolphins turned out to have fishing lures stuck inside them.

“Whenever animals become reliant on humans for food, it puts them at jeopardy,” says Dr. Randy Wells, director of dolphin research at Sarasota’s Mote Marine Laboratory. “If they are coming to boats or piers to get fish, they are swimming through a maze of lines, hooks and lures and those lines are designed to be invisible under water.”

Some dolphins do however seem to have figure out how to stay clear of harms way. A bottlenose dolphin nicknamed “Beggar” has been soliciting free meals in a narrow stretch of Intracoastal Waterway near Nokomis Beach since he was a juvenile 20 years ago. Despite routinely swimming just inches from boat propellers, the skin of Beggar’s 8 feet long body is free of major scars. Hopefully, the same is true for the inside of his 400 pound body.

As if the menace of razor sharp propeller blades, invisible fishing lines and jagged double hooks weren’t enough, bottlenose dolphins also stand the risk of encountering anglers who may not appreciate having their bait or catch snatched away by a hungry cetacean. A commercial fisherman out of Panama City, Florida has been sentenced to two years in prison after throwing pipe bombs at dolphins trying to steal his catch. Off Panama City, tour operators have been feeding dolphins for years to assure their presence at the popular “swim-with-the-dolphins” tours.

Feeding the Florida dolphins is illegal under both state and federal law, with federal law banning wild dolphin feeding in the early 1990s. Feeding wild dolphins can also be dangerous and the abovementioned “Beggar” dolphin has for instance sent dozens of overfriendly patters to the hospital for stitches and antibiotics.

Hand-feeding aside, a severe red tide in 2005 seems to have made the habit of interacting with humans for food much more widespread than before among the Florida dolphins. The red tide wiped out 75-95 percent of the dolphin’s usual prey fish and the hungry dolphins eventually realised that they could fill their bellies by picking bait fish off fishing lines.

“We suspect that the dolphins were
hungry,” Wells explains. “Their main prey
base was gone. Seeing a fresh pin fish
dangling from a line might look pretty
good to them. And once they learned
that anglers are a source of food, they
don’t forget that very quickly.”

This Saturday, about 55 False killer whales (Pseudorca crassidens) stranded on Long Beach, Kommetjie, in South Africa. Both adults and calves began to appear on the shore around 5.30 in the morning, perhaps as a result of the bad weather. This incident is the second large stranding in a short period of time; in March about 80 whales stranded in Hamelin Bay on Western Australia’s southern coast.

Massive whale strandings are however not new phenomenon; Long Beach was for instance the site of a heartbreaking stranding in 1928 when 103 whales beached on Christmas Eve. This was before marine experts and volunteers had figured out how to save stranded whales, so all 103 animals died in the scorching sun. This was also during a period when whales were chiefly seen as something that you hunted; not something worth saving.

So, why do whales beach? Scientists are still in the dark on when it comes to this bewildering question and no hypothesis has been confirmed yet. In his book “Whales and Dolphins of the Southern African Subregion”, whale researcher Peter Best lists a long row of hypotheses – all of the seemingly plausible – and also states that whale strandings may be due to a combination of several factors.

“It is very likely that no single cause is responsible and elements of some hypotheses may have to act in combination to produce the circumstances for a mass stranding to occur”, Best explains.

Here are some hypotheses put forward by marine scientists:

• Parasites infesting the middle ear can cause severe disorientation and make it difficult for whales to navigate. If one or several animals in a group develop middle-ear problems, the other ones might follow them due to their social bonding, even if it means stranding on a beach.
• An injured or sick whale may send out a distress call that the others follow all the way up on the beach.
• If cetaceans navigate using the earth’s geomagnetic field, geomagnetic disturbances could make them disorientated and, if they’re unlucky, even cause them to beach.
• Beachings may be a density-dependent response, where a population approaching its carrying capacity suffers increased natural mortality.
• Whales hunting for food close to the shoreline may accidently strand themselves in the pursuit.
• Whales might end up on beaches after getting caught in a rip current, getting their sonar confused. A rip current (also known as rip tide) is a strong surface flow of water returning seaward from near the shore.
• Beaked whales seem to be extra sensitive to mid-range sonar, so human activities may be to blame for the stranding of beaked whales.

The Snubfin dolphin (Orcaella heinsohni), recognized as a species as recently as 2005, have been spotted while utilizing a rare hunting technique previously only noted in the Irrawaddy dolphin (Orcaella brevirostris), a close relative of the Snubfin.

The unusual group hunting technique involves chasing the prey fish to the surface of the ocean and rounding them up by spitting jets of water at them. Once the fish is packed together in a reasonably small “cylinder”, the dolphins move in to devour them.

According to WWF Australia’s marine and coasts manager Lydia Gibson, the behaviour was first noticed in Australia off the Kimberley Coast.

We still know very little about the Snubfin dolphin, which lives along Australia’s northern coast in a number of locations off the Queensland and Northern Territory coasts, as well as the Kimberley region of Western Australia. It is listed as Near Threatened on the IUCN Red List of Threatened Species, chiefly due to habitat destruction. Since Snubfin dolphins live close to shore, they are also more likely to end up in gill nets and drown compared to more pelagic species of dolphin.