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To: Journey North
From: Anne Smrcina
Stellwagen Bank National Marine Sanctuary
Plymouth, Massachusetts
Here's the third and final installment of Answers to your whale questions. I'd like to congratulate all of you on your excellent questions and interest in the subject.
From Mr. Ward's class at the Breck School in Minnesota:
Q. Why did you get involved in whales instead of the rain forest or another animal?
A. Since I am not a whale researcher myself (but an educator for a marine sanctuary), I took that question to two scientists who study whales -- Phil Hamilton at the New England Aquarium who specializes in right whales and Dave Mattila at the Center for Coastal Studies who is an expert on humpbacks (although both know a lot about all kinds of whales). They both give similar answers. It was a combination of a love for the ocean and an interest in animal studies. Both men combined these interests and focused on whales as species that provided many questions that needed to be answered. And as we have seen over the past few months, there are still many questions about these animals that remain unanswered -- potential research fields for some of you perhaps?
Q. Why do whales live in oceans and not lakes? Some people say because of salt water but why do they need salt water and not regular water? And if they need salt water, what about the Great Salt Lake?
A. That's quite a question (or 3 of them). Whales have evolved over millions of years, adapting to conditions around them. Their niche is the ocean -- since they don't have legs it would be impossible to cross land and get to a lake. Because of their great size, they probably need the salt water to aid in buoyancy (as you probably know from experience, it's easier to float in salt water than fresh water since salt water is more dense). In addition, because of their great size, the great whales need a lot of food -- a modest sized lake would probably not be able to support even one whale for any length of time. And even a large lake would not be able to support a genetically healthy population of whales. A population of only a few whales would lead to inbreeding and the potential for genetic defects. And finally, the Great Salt Lake does not support the types of prey that right whales feed on, even if the whales could make it out there.
Q. Why do they look like they are upside down?
A. Answer number 1 is: stop standing on your head when looking at them. Answer number 2 (the serious one) is: it's
because of how the animals head and jaw are shaped. In humans (and even in the toothed whales), the head is large
and the lower jaw is much smaller. In the baleen whales, the lower jaw is much bigger than the upper jaw. The rostrum
at the top of the head is small and narrow. It's just a matter of perspective.
From Cassy and Stephanie at the Homer Intermediate School in Alaska:
Q. Do the barnacles that attach themselves to whales harm the whales?
A. NO
Q. How fast can a humpback whale move backwards?
A. Whales don't do any significant backwards swimming -- they can do a bit of maneuvering with their flippers,
but this is quite slow.
Q. What time of the year do humpbacks mate?
A. Winter months -- Dec-Feb down in the Caribbean
Q. Where do right whales mate?
A. primarily during July and August in the Bay of Fundy and Scotian Shelf
Q. Do they mate with the same partner for life?
A. NO, we don't think there is any pairing up in baleen whales
Q. How long is the pregnancy period for whales?
A. About one year
From Mrs. Holmes' class at the St. Clair Public School in Minnesota:
Q. Is the killer whale really a whale or is it a dolphin?
A. It's both. The orca or killer whale has this classification:
Class Mammalia
Order Cetacea (whales)
Suborder Odontoceti (toothed whale)
Family Delphinidae (dolphins and killer whales)
Q. Do you spend a lot of time doing studies on whales and how they talk back and forth? Well thank you for your time.
A. Although I don't spend any time in whale communication research, there are several scientists who devote all of their attention to these studies. Work is proceeding on the reasons for humpback whale songs and identifying the song-makers; other studies are looking at how sperm whales communicate with clicking sounds -- and what those messages might mean. Another researcher is using Navy underwater sensing equipment and past recordings to locate blues and other wide-ranging whales. The biennial conference of the Marine Mammal Society, held in Florida this past December, brought many of these researchers together to present their findings to their peers. There were hundreds of papers on many diverse topics, and many on whale communication.
Fron Kelly Crandall and Sandy Beck of the Academic Resource Center, Tallahassee, Florida come these questions
about right whales:
Q. How are the habitats and temperatures different in summering and wintering waters?
A. The summer and winter grounds for whales do not have vastly different temperatures. According to some researchers,
the limiting factor seems to be the warmth of the water -- not the cold. Right whales are rarely found in waters
above 18degrees C, and seem to prefer a range between 10-18degrees C. The habitats are somewhat different in that
the winter calving grounds are fairly shallow to possibly protect against predators and they do not have the abundance
of prey since the whales are not feeding there. The summer feeding grounds are a bit colder and support large copepod
concentrations not found down south.
Q. Do the whale calves need special temperatures in order to survive?
A. Although the whales are born with a comparably thinner blubber layer than adults, they could probably make it
up north and survive in colder water. But the nursing period down south gives them added blubber in order to conserve
heat and extra energy when needed for the long trip up north.
Q. Do whales of all ages migrate?
A. Migration in right whales is a big unknown. Pregnant females migrate to the calving grounds, but we really don't
know where all the others -- juveniles, non-pregnant females, and males -- go in the winter. Some may accompany
the pregnant females (one example is Lindsay, a large adult male who died this year off the Florida coast from
a ship collision), others may be going to a wintering ground that has not yet been discovered.
Q. When and where are the young born?
A. In the shallow coastal areas off the Georgia-Florida coast (generally as far south as mid-Florida).
Hope you enjoyed these answers to your questions. Until next year, this is Anne Smrcina signing off.
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