Blog Tags: Whale Wednesday
Here’s a whale-only quiz just for fun -- but no prizes here -- you have to go take the real quiz.
1. Scientists use the distinctive areas of hard pale skin on Northern right whales to tell individuals apart. What are they called?
On this hump day, a few cetaceous stories for your perusal:
As you've probably heard, the team behind Sunday’s Oscar-winning documentary “The Cove” exposed Santa Monica sushi restaurant The Hump for serving illegal whale meat. The possession or sale of marine mammals -- in this case, the endangered sei whale -- is a violation of the Marine Mammal Protection Act, and can lead to a year in prison and a fine of $20,000.
And on the brighter side, the BBC has a remarkable slideshow of images showing a sperm whale surface feeding off the coast of New Zealand. Surface feeding is uncommon for sperm whales, who usually hunt many meters below the sea’s surface -- this individual must have been pretty hungry.
The researchers have evidence of the whales staying together over several months in the Gulf of Mexico. And their behavior varied with each deep dive, indicating that they alternate roles to spread out the physiological demand of the 1,000-meter dives.
One researcher said that the some whales appeared to guard the bottom of a squid bait ball, while others took advantage of the center of the ball.
Other research has suggested dolphins may exhibit herding behavior, but this is the first evidence in sperm whales; some scientists remain skeptical.
Just remember, whales: there is no "I" in "team."
Bats and toothed whales share the ability to squeak and click their way to prey. And now two new studies in this week’s journal Current Biology reveal that their echolocation, which evolved independently in the two groups, has a similar underlying molecular mechanism.
There are plenty of examples of evolutionary convergence, such as the tusks of elephants and walruses, or the bioluminescence of fireflies and jellyfish.
But it’s highly unusual for convergence to occur at the molecular level. Turns out the inner ear hair cells of both the bottlenose dolphin (a toothed whale) and 10 species of bats contain a protein called prestin, which plays an important role in echolocation.
But not all echolocaters are created equal. Because the speed of sound in water is five times that in air, dolphins can use echolocation for more than 100 meters. Bats can only do so for a few meters.
(Hat tip to Monterey Bay’s Sea Notes blog for this story.)
The researchers discovered that the two groups, which they have creatively dubbed "Type 1" and "Type 2" have different wear on their teeth, suggesting different diets and thus different ecological niches. Then, genetic analysis confirmed that the two types of killer whale belong to different populations.
The scientists compared the findings to how Darwin's finches adapted to fill unique ecological roles.
So what does this mean for the future of the North Atlantic killer whales? If Type 1 and Type 2 become separate species, they would require separate conservation monitoring efforts.
And if that happens, hopefully the powers that be will think of some catchier names for them.
As you know, Wednesdays are normally devoted to blogging about the latest whale news. But I’ve redubbed today’s post in honor of yesterday's news about a certain sleek giant of the sea who continues to fetch exorbitant auction prices as it heads toward extinction. It makes you go, “Wha?”
Yesterday, a 513-pound bluefin tuna sold for $177,000 -- the most since 2001 -- in an auction at Tokyo’s famous fish market.
Ironically, the sale took place amid a decline in Japanese tuna consumption due to the nation’s worst recession since World War II.
So as Tokyo’s fish market representatives fret over how to keep c
An Australian paleobiologist has made a curious discovery about the origins of baleen whales. Studying the 25-million-year-old fossil of a primitive toothed baleen whale, Mammalodon colliveri, Dr. Erich Fitzgerald hypothesized that the early whale used its tongue and short, blunt snout to suck small prey from sand and mud on the seafloor. Yummy.
Fitzgerald’s work supports Darwin's notion that some of the earliest baleen whales may have been mudsuckers before they were filter-feeders.
And apparently the three-meter-long Mammalodon was actually a dwarf, though its name brings to mind its relative, the blue whale -- the largest animall in the history of the world.
As Dr. Fitzgerald said, “Clearly the seas off southern Australia were a cradle for the evolution of a variety of tiny, weird whales that seem to have lived nowhere else.”
Some consider the great white shark to be the fiercest predator in the ocean. Now Free Willy is giving the species a run for its money. Orca whales' diet traditionally includes fish, squid, birds, seals, and other whales. Now some are adding Jaws to the menu.
Several populations of orca whales have learned how to attack sharks, including the great white, with various techniques, including what some scientists are calling the “karate chop.” To execute this sly move, the orca drives the shark to the surface, then comes down on top of the shark and turns it upside down, at which point it enters a paralyzed state. In fact, all the attack methods ultimately end with the shark on its back.
If you want more, watch this recent video of one such showdown.
Here at Whale Wednesday, we generally talk about the amazing life of whales… while they are alive. But like everything in nature, cetaceans pass on. And good thing, too, if you are a boneworm.
These strange, tiny creatures feast on the bones of mammal carcasses on the sea floor. Bobbing along as microscopic larvae until they come in contact with a whale or elephant seal, they then latch on, sending root-like structures into the bones and feathery arms into the water. The bacteria in these roots break down bone protein, while the feathery appendages draw in oxygen. And that’s not the strangest part.
All boneworms start off male, but as they sexually mature, become female. However, if a male larvae lands on a female boneworm, he will become a male worm, though remain microscopic in size. He will then go on to fertilize the females eggs, which will result in all-male larvae. And the cycle begins again.
Space is often touted as the final frontier, but the depths of the oceans hold much more mystery… and bone eating worms.
It's been a while since we started the Whale Wednesday weekly feature, and I don't think beaked whales have ever gotten their day in the spotlight. Today's the day, then, for this mysterious group of cetaceans.
The BBC reports that researchers from Duke University observed the largest group of Arnoux's beaked whales -- around 60 -- ever recorded, off the coast of Antarctica.
Male beaked whales have tusks that emerge from their lower jaws, and in general beaked whales are deep divers. Of the 21 known species of beaked whales, only a few are well-known, including the Cuvier's beaked whale and the Baird's beaked whale.
As one of the Duke scientists, Dr. Ari Friedlander, told BBC, "The Arnoux's were a unique and amazing experience. Hopefully this brief glimpse will spawn further work to better understand the species, their distribution and behaviour, and how these animals fit into the larger ecology of the southern ocean."
- ICCAT Moves to Properly Manage Bluefin Tuna, but Doesn’t Take Action for Sharks and Swordfish Posted Wed, November 26, 2014
- Creature Feature: Ocean Sunfish Posted Thu, November 20, 2014
- Oceana in Chile Submits Recommendations for Lowering Common Hake Catch Quotas Posted Mon, November 24, 2014
- Ocean Roundup: Seals Can Pick up Pings from Acoustic Tags on Fish, Climate Change Making Crabs “Sluggish,” and More Posted Fri, November 21, 2014
- Video: Watch the Incredible Migration of Thousands of Giant Spider Crabs in Australia Posted Mon, November 24, 2014