Answers From the Whale Expert 2002
From: Texas Episcopal High School Q: Can a group of pregnant cows protect themselves from predators? Can the male whales protect themselves? Do the males help raise and protect the female and newborn? A: Although gray whales are often found together in groups, it doesn't appear that they cooperate with one another to ward off predators. If an adult gray whale of either sex is attacked by a group of killer whales their fate really hangs on how persistent the killer whales happen to be. Once a female gray whale is pregnant, the males have completed their part of the reproductive process. The males don't seem to show much interest in the young. Q: Do the gray whales spend more time in the northern areas near Alaska or in the lagoons in California? A: Gray whales spend about 6-7 months of their year feeding in Alaskan waters above the Arctic Circle and only about 1 month (for males and females without a calf) in Mexican waters. Cows with calves spend about three months in the lagoons. It takes gray whales about 4 months to migrate to and from the lagoons (2 months each way). Q: How violent can the gray whales be? Are they ever the aggressor? A: The whalers called gray whales the "devil fish" because they often attacked the small boats used to catch them. Remember that most of this activity took place in the restricted areas of the lagoons and much of it involved mothers with calves. Also, killing a 35 foot animal with harpoons took a while, so wounded whales and small boats were in close proximity for a while. In recent times, gray whales seem to have forgotten the past and are curious or even playful with humans in small boats. From: Vermont Ferrisburgh Central School Q: How deep can whales dive? What depth is where there is most food? Ben A: How deep a whale dives depends on where its food lives. For gray whales, their primary prey are the small crustaceans (called amphipods) that live in bottom sediments off Alaska. These crustaceans are found in relatively shallow waters between about 25 feet and about 150 feet deep. Q: How high can a gray whale jump out of the water? Kyle A: Gray whales commonly leap out of the water which is called breaching. I haven't seen a gray whale make it completely out of the water on a jump. Most of the time they get about 2/3 of the way out and then crash back down. It isn't unusual for the same animal to breach 2 or 3 times in a row. No one knows why they do it. Q: How do the grey whales defend themselves against a shark? Ben, Brittany and Kyle A: A shark may occasionally take a bite out of a calf, although I can't remember any confirmed reports—but I don't think that they often attack adult whales. I think gray whales are just too big for sharks to tangle with. When a dead whale washes up on the beach, it isn't unusual to see scars from shark bites on their bodies. We think that these bites occur after the whale is dead. From: Washington
A: Right now, April 9th, most of the gray whale mothers with calves are leaving the lagoons to head north. The rest of the population is strung out along along the coast of North America from Central California to SE Alaska. Q: Are the whales anywhere near Washington state? A: Today, I bet almost 20% of the eastern Pacific population of gray whales are off the coast of Washington. From: Illinois Kildeer School Q: First Graders at Kildeer School want to know why dolphins follow the whales? The first graders suggested the following reasons: 1. They want to eat what the gray whale eats. 2. The whales are guiding the way for dolphins. 3. The whales give protection. 4. The whales keep the dolphins warm. 5. The dolphins follow just for fun. A: I vote for answer #5. I have often seen dolphins riding the small wave of pressure that is pushed ahead by a whale when it swims. Whales are like ships to dolphins, and the dolphins seem to like to get a free ride on the pressure wave the ahead of either one. Sometimes it seems like most of what dolphins do is just for the fun of it. What a life! From: Kathy Vires Q: What keeps whale skin from getting frost bitten or freezing when swimming in very cold water? A: Wow! that's a good question. I think that gray whales, and probably all whales, are loosing heat through their skin all the time. When we look at gray whales along the California coast with thermal sensors, their surface is clearly warmer than the surrounding environment. Whales are like a big engine that is always creating heat through metabolism of fat and movement of muscles, and so they need a way to dissipate that heat. The tail flukes and tongue are places where we know they slough heat, but the skin is also a place to slough heat. That is a long way of saying that I think that the skin is fairly warm. I imagine that too much sun is a bigger problem than too much cold. Wayne Perryman Fisheries Biologist National Marine Fisheries Service
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