Tag Archives: Marine Mammal

Learning About Whales From the Inside Out!

Gray whales are some of the most massive mammals that roam our ocean because they reach lengths of almost 45 feet.  Could you even imagine what it would be like to come face to face with a whale of that size? It’s pretty mind-blowing to think of!

An average gray whale will reach lengths of about 36 to 45 feet and weigh upwards of almost 80,000 pounds!  Their tongue alone is about 5 feet long and can weigh almost 3000 pounds.  But that’s not the only impressive measurement.  For us humans our brain is about 3 pounds whereas for gray whale their brains are over 9 pounds.  That’s triple what our own brains weigh! Not only that but the heart of a gray whale weighs over 285 pounds alone.  These guys have some pretty enormous parts inside of them.  

Image Left Gray Whale Brain, Image Right Gray Whale Heart

The backbone of a gray whale is composed of 56 vertebrae – vertebrae that are so large Native Americans used to use their vertebrae as stools!  This just further proves the point that gray whales are massive mammals!

But their size is not the only impressive thing about their anatomy. The lungs of a gray whale are directly connected to both blowholes rather than being connected to their mouth.  And when they breathe they expel 100 gallons of air making a heart-shaped spout that will reach heights of almost 15 feet!  Gray whales also have an extremely flexible rib cage that comes in handy when they dive to deep depths.  With this flexibility their rib cage will bend as they dive down preventing anything from breaking.  This adaptation definitely comes in handy as Gray whales can to depths of almost 400 feet deep lasting anywhere from 3 to 15 minutes.

Since Gray Whales reach such impressive lengths they must each a lot in order to sustain them.  When they are first-born young gray whales will consume milk from their mothers that is about 53% fat.  This milk is so fatty that is has the consistency of cottage cheese!  But as they grow older they no longer depend on their mother’s milk, instead they feed on things found in the ocean.  Gray Whales have an average of about 130 to 180 plates of baleen on each side of their upper jaw. Baleen is a hair-like structure (made of keratin) that hangs down from the upper jaw of a whale.  While feeding they utilize their baleen to filter out water and sediment while keeping the delicious benthic invertebrates trapped in their mouth.

Sources

Gray Whale.  National Audubon Society: Guide to Marine Mammals of the World.  2002.

Written By: Alex Feltes

What Makes a Dolphin a Dolphin?

Most everyone on the planet knows what a dolphin is and what they look like. Dolphins are incredibly popular animals and just happen to be one of the most charismatic of all marine mammal species. But you may not have known that dolphins belong to an order of species that encompasses many of our favorite mammalian relatives. This is the order Cetacea that contains both baleen whales as well as toothed whales, which is the one our familiar dolphins are a part of. Today we are going to talk about some differences between baleen whales and toothed whales and how we can identify what makes a dolphin a dolphin.

First off lets talk about baleen whales and toothed whales. The baleen whales scientific sub-order is officially called Mysticeti and contains whales such as blue whales, gray whales, and humpback whales. The toothed whales scientific sub-order is officially termed Odontoceti and contains whales like porpoises, orca whales, and of course dolphins! There are many similarities between the two sub-orders such as they both give live birth, have blowholes, and use sounds to communicate with each other, as well as many others. However, there are some glaring differences between the two that allow us to really define what a dolphin exactly is.

The first major difference is that Mysticetes use baleen, (large overlapping plates used to filter feed), to eat small organisms like krill. Odontocetes swallow their prey whole and use their teeth for grabbing and gripping instead of chewing. Secondly, Mysticetes are also mostly solitary animals only coming together for mating or when food is plentiful in a given spot whereas most Odontocetes, especially dolphins shown above, travel in pods. Thirdly, Odontocete jaws are much more asymmetrical (different on either side of the jaw) than Mysticetes so that they can receive sound waves from echolocation much better while they are feeding and locate their prey. Fourthly, sounds made by these two are different; Mysticetes produce much lower frequency songs to navigate and communicate whereas Odontocetes produce many more high frequency clicks and whistles used to locate prey on top of communication and navigation. Fifthly, Mysticetes have double blowholes (shown to the right) while Odontocetes have single ones. And lastly is their size! Odontocetes, with the exception of sperm whales, are generally much smaller than their Mysticete relatives. So, if you see a smaller marine mammal producing high frequency clicks, breathing through a single blowhole, eating larger prey like fish and squid, and smaller in size chances are it’s a dolphin!

Kopelman, A. H. (n.d.). CETACEANS. Retrieved October 27, 2016, from http://www.cresli.org/cresli/cetacean/cetapage.html

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We would like to thank you for visiting our blog. Catalina Island Marine Institute is a hands-on marine science program with an emphasis on ocean exploration. Our classes and activities are designed to inspire students toward future success in their academic and personal pursuits. This blog is intended to provide you with up-to-date news and information about our camp programs, as well as current science and ocean happenings. This blog has been created by our staff who have at least a Bachelors Degree usually in marine science or related subjects. We encourage you to also follow us on Facebook, Instagram, Google+, Twitter, and Vine to see even more of our interesting science and ocean information. Feel free to leave comments, questions, or share our blog with others. Please visit www.cimi.org for additional information. Happy Reading!

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