Studying ocean life, mammals, or endangered species? Use this information to put together a blue whale unit study to complement them all. You might want to use these free animal report printables to get started.
Imagine a creature that can grow over 100 feet long, weigh up to 200 tons, and have a heart the size of a Volkswagen Beetle. Sounds like something of myths and legends, doesn’t it? Or maybe something prehistoric?
This creature actually exists on Earth right now. The blue whale is the largest animal on Earth. Actually, blue whales are the largest animal to have ever lived. These huge creatures are distributed throughout the world’s oceans. However, even with this large expanse of habitat, the blue whale population is very low and they are considered an endangered species.
Let’s learn more about the blue whale and why their endangered status is a concern.
Blue Whale Facts
Where are blue whales found?
As stated before, blue whales are found throughout the world’s oceans. In the summer months, they migrate toward the poles to feed and then migrate toward the equator to breed. Blue whales tend to stay in deeper water and avoid coastal areas.
What do blue whales eat?
You might think that the largest animal in the world would be a fierce predator feeding on whatever gets in its way. The truth is blue whales actually have a pretty basic diet of some of the smallest animals in the ocean.
Krill are mainstay of the blue whale diet. These small crustaceans are on average only about 2 inches long. Blue whales filter krill out of large gulps of water at the rate of 8000 tons per day of krill. That’s about 40 million krill!
What is the blue whale’s life cycle?
Since blue whales are mammals, they give birth to live young one at a time every 2 to 3 years. Newborn blue whales are huge in their own right. They can be up to 25 feet long and weigh up to 3 tons. During the first 8-12 months of life, a baby blue whale will eat nothing but mother’s milk and gain 200 pounds a day.
When a baby blue whale can hunt krill on its own, it is weaned and can then make the migration with the adults usually traveling in groups of 2 or 3. Blue whales can live on average 80-90 years.
Do blue whales make noise?
Blue whales are among the loudest animals on the planet. A jet engine reaches levels of 140 decibels. The blue whale crushes that with an impressive 188 decibels! Blue whale sounds can be heard up to 1000 miles away. Click HERE to listen to blue whale sounds.
Related Post: Ocean Animals Unit Study
Blue Whale Populations
Blue whales are considered endangered animals. Even though their habitat spans all the Earth’s oceans, there are an estimated 5-10,000 blue whales in the Southern Hemisphere, and only around 3-4,000 in the Northern Hemisphere according to the American Cetacean Society.
In 1900, a demand for whale oil and whale baleen drove the whaling industry to hunt and kill blue whales by the thousands. Prior to 1900, there was estimated to be 350,000 blue whales. Up to 99% of all Blue Whales were killed by whaling before the International Whaling Commission banned commercial whaling for blue whales in 1966.
Since then, recovery for the blue whale has been slow. New threats to the blue whale have emerged, such as water pollution, habitat destruction, over fishing of krill, and collisions with boats.
Impact Of Blue Whales On The Environment
Nature is a delicate balance with each species in an ecosystem having a very special role. If one species is removed or its populations thrown out of balance (either an profound increase or decrease), all other organisms will be affected. Most of the time, these effects are not good.
Blue whales are at the top of the oceans’ food chain. They eat huge amounts of krill each day. If the blue whales disappear, this could cause an increase in the number of krill in the ocean. This overpopulation would mean more competition for the same food supply. This could lead to a drop in the populations of other species.
Whale poop is even important to the oceans’ food chain. Phytoplankton need the nutrients in whale poop to thrive. Phytoplankton are an important food source for lots of marine life, such as krill. Phytoplankton, also, plays an important role in removing carbon from our atmosphere – up to 400,000 tons per year.