Beaked whales: Your questions answered

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Song of the Whale has been monitoring the waters off the Canary IslandsEnvironment correspondent Richard Black joined researchers on board the yacht Song of the Whale as they looked and listened for whales around the Canary Islands.

Here, Richard and the research team from the International Fund for Animal Welfare (Ifaw) answer your questions on beaked whales, which are probably the least understood large mammals on the planet, and what the team discovered during the week at sea.

From Martijn Hover, Helmond, Netherlands:I thought I knew a bit about marine mammals and I'd never even heard of beaked whales. Does 'beaked' mean that they have no teeth?

Claire Lacey, Ifaw: Beaked whales are elusive and enigmatic creatures, and they're a group of whales that hasn't been well studied. You probably have heard of one of the species, the northern bottlenose whale, because it was one of those that swam up the Thames a few years ago, and there was a lot of news coverage of that event.

Ollie Boisseau, Ifaw: Male beaked whales do have teeth but typically only two on the outside of the jaw that are not used for eating as far as we know. Instead it's likely that they suck in their prey.

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From Emilee N. Gabriel, Baltimore, USA:How come there are so few of these special beaked whales in the world?

Ollie Boisseau, Ifaw: We don't really understand the status of any of the beaked whale species. We don't know how many there are or even really where they are. That's one of the reason why threats such as military sonar are such a concern, because we don't really understand how much the whales are affected.

Richard Black, BBCNews:The Red List of Threatened Species lists 17 species of beaked whale. And for 15 of them, it concludes there is not enough evidence to assess whether they are threatened to any degree. Other sources list more species, about 20 or 21. So that's evidence of how little we know about them.

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From Chuck Gary, Lisbon, Portugal: Are beaked whales indeed whales? Or has a mistaken species identity due to sheer size, led to the use of that name which remained, and they are actually dolphin family related?

And from Frank R. Tangherlini, San Diego, USA:How closely related to dolphins are beaked whales? Dolphins also use an echo location system - are the beaked whales related morphologically as well as DNA wise? How far back in the fossil record do such creatures go?

Claire Lacey, Ifaw: Just like killer whales, pilot whales and sperm whales, beaked whales are members of the odontocete branch of cetaceans, as are dolphins. The word "dolphin" is a name, not a species.

Vassili Papastavrou, Ifaw: Beaked whales, and killer whales and pilot whales, are more closely related to dolphins than they are to the baleen whales such as blues and humpbacks.

Beaked whales are generally bigger than dolphins. All the odontocetes use echo-location to find their prey. I'm not sure how far back beaked whales go in the fossil record, but certainly when you look at cetaceans overall we are seeing now a tiny fraction of all the species that have existed on Earth.

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From Olivia Bell, Rockhampton, Australia: How many different kinds of whales are there? How many different colours of whales are there?

Claire Lacey, Ifaw: There are about 80 species of cetacean, although the precise taxonomy is still changing. In terms of colours, you have everything from the white of the beluga to black species such as pilot whales.

There are of course species called gray and blue whale, although the blue was also sometimes known as the "sulphur-bottom" because diatoms clinging to its skin gave it a yellowish tinge, as we have seen here with the fins of the some of the beaked whales. And the humpback dolphins of the South China Sea are a striking pink colour.

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From Morgan Dougherty, Brantford, Ontario, Canada: I was wondering how long the scientists have been researching these fascinating creatures and if they like their jobs? I'm considering going into marine biology so I just wanted to say you guys are real heroes to me!Advertisement

Life as a whale research scientist...

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From J.E. Simkin, Nashua, USA: Why do beaked whales dive so deep? Is there food to be had at such depths? I thought most whales live on plankton, found within 100 feet (33 metres) of the surface.

Claude Wadsworth, USA asks: Do these whales ever come up for air?! Do you know how long they can stay down for?

And from Samantha Bergeron, Ottawa, Canada: What does the whale's diet consist of and what exactly make them different from other species of whales besides the beak? Also why are they so difficult to research and document?

Ollie Boisseau, Ifaw: It's difficult to study beaked whales because they spend most of their time deep in the ocean. In fact, you could say they dive upwards to breathe, rather than diving downwards for food.

They go to great depths to find their prey, which are mainly mesopelagic (mid-ocean) squid. So dives would range from about 500m to 2km. There's evidence from examining the stomach contents of dead beaked whales that they eat fish as well.

Vassili Papastavrou, Ifaw: It's the baleen whales that feed near the surface, and they eat not only plankton but small schooling fish.

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From Raza Rizvi, Tylers Green, Bucks: Do the whales use different frequencies and intonations when making mating calls as opposed to hunting food? (Is finding the mate a different sort of hunt?!)

Ollie Boisseau, Ifaw: Beaked whales echo-locate to find food but we don't know for sure whether they use sound in a social context. Baleen whales, by contrast, use sound primarily for social reasons; and sperm whales, which are also deep divers, use it for both purposes, social and prey-finding. We don't really understand at the moment how beaked whales find each other in the open marine environment but clearly they do find each other.

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From Felix Hofer, Dublin, Ireland: Do beaked whales live in groups?Two's company... beaked whales live in groups of up to 30 members

Ollie Boisseau, Ifaw: We think all beaked whales live in groups, with anywhere between two and about 30 members.

However, we do sight singletons too, although - to be fair - that is a bit unusual.

We know that with other whales that are social they may spend parts of their lives alone.

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From Cory Nelson, Indialantic, USA: Can you give us some examples of the geographical range where different species of whale are found?

Richard Black, BBC News: It would be impossible for us to give all the ranges of all the 80-odd whale species, but what we have prepared is a map of the ranges, or what are believed to be the ranges, of the four beaked whale species seen by Song of the Whale this year - Cuvier's (Ziphius cavirostris), Blainville's (Mesoplodon densirostris), Sowerby's (Mesoplodon bidens) and the northern bottlenose whale (Hyperoodon ampullatus).

And on our <a class="inlineText" href="http://news.bbc.co.uk/1/shared/spl/hi/guides/456900/456973/html/default.stm">Guide to the Great Whales</a>, you can also find ranges of better-known species such as the minke, fin and humpback.

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From Clint, Trinidad & Tobago: Does anyone hunt this type of whale for meat? Are any found in the Caribbean?

Vassili Papastavrou, Ifaw: There's little evidence of them in the Caribbean, although they are found around the Bahamas. I think it's more likely that they would frequent the northern Caribbean than the southern end.

Around Trinidad and Tobago, the water would probably be too shallow for them and they might also be put off by noise from oil exploration.

On the hunting side, Norway and the UK used to hunt the northern bottlenose whale, and currently Japan has a hunt of Baird's beaked whale, the largest of the species, which does not fall under the jurisdiction of the International Whaling Commission.

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From Erika Meyer, Tacoma, USA: How do the military sonar systems hurt these whales? How do we know that they do harm the whales if we barely know anything about the species?

And from Renee, Melbourne, USA: Are there laws protecting the animals in regards to military operations undersea?

Ollie Boisseau, Ifaw: We know they're affected by military sonar because there have been a number of high-profile incidents, not least here in the Canaries, where tests of military sonar have led to beaked whales stranding, either alive but in distress, or dead. Even the US navy has acknowledged a link between sonar and whale mortality.

Antonella Servidios, Society for the Study of Cetaceans in the Canary Archipelago (Secac): Following the series of strandings related to military tests here, the navy is now forbidden from testing sonar in the waters around the islands.

Richard Black, BBC News: For more on strandings in the Canaries and ideas on why military sonar affects beaked whales, please <a class="inlineText" href="/1/hi/sci/tech/7642366.stm">see this article</a>.

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From Rob Schack, United States: I teach marine science and am now wondering if I have my sense of sonar correct. I had believed that the lower jaw vibrated in response to an incoming sound wave but is it the air sac that vibrates instead or in conjunction with the jaw? Wouldn't the air sac change with depth and, therefore, change the sound received with respect to depth? Is the air sac kept open by cartilage (similar to our tracheal rings)?

Richard Black, BBC News: There's no-one on this boat who's a real expert in this area, unfortunately. But having done a bit of research on the issue, it seems that the reception system for auditory information might be a bit more complicated than previously believed, including acoustic lenses of fat, air sacs, and bone. Sorry not to be able to give a fuller answer.

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From Nathan Malkow, Winthrop, USA: I am a former commercial fisherman in the Pacific Ocean with a Bachelor of Science In Zoology. I have spent the last four years working with salmon and steelhead, listed as endangered species. How do I go about working on the research vessel? Would you have any need for a hard working crew member?!Advertisement

Song of the Whale skipper Richard McLanaghan outlines requirements for joining the team

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From Clarence, Nigeria: Do whales ever eat humans? Is there any species of whale that eats humans?

Claire Lacey, Ifaw: There's been no documented case of any whale eating a human, despite the well-known Jonah story. But whales and dolphins have been known to attack humans.

Antonella Servidios, Secac: Pilot whales will sometimes show aggression to protect their calves or if they feel threatened in general. So for example, they might swim towards you and snap their teeth.

Claire Lacey: The bottom line is they are wild animals, and if we go into their domain we have to treat them with a certain amount of respect.

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From Wodzicka, Wroclaw, Poland: Have beaked whales ever been filmed? Is there a database about beaked whales that I could use to find out more information?

And from Brenda Merchant, USA: Is there any way that I can get regular updates on the project or a website to go to for updates?

John Galliver, BBC News: I've been filming beaked whales on this trip but it's quite hard to do. They don't spend much time at the surface, and we stay back quite far from them on the boat. Nevertheless, as you can see, we have managed to pick up a couple of the species.Advertisement

Footage of the whales spotted by the Song of the Whale team

Claire Lacey, Ifaw: There's a <a class="inlineText" href="www.beakedwhaleresource.com">website</a> which has quite a lot of information. We are posting a <a class="inlineText" href="www.ifaw.org/sotw;">diary of our own research</a>, and the websites of our collaborators at El Hierro would also be worth looking at, such as the University of La Laguna, the Marine Mammal Behavior Laboratory at Woods Hole Institute of Oceanography, and the Sea Mammal Research Unit at St Andrews University.