"We owe it to our children to be better stewards of the environment. The alternative? - a world without whales. It's too terrible to imagine." Pierce Brosnan

What Are Whales?

To understand whales, we must first define and understand them to gain an awareness of their habitat and capabilities. Research into aspects of whales revealed many interest facts about them. How can we save whales if we do not know what they are, how they live, where they live?

Whales are marine mammals that are:

  • Air breathing mammals that are “aquatic vertebrates” who habitat only in the water during their lifetime and have a backbone (De luliis and Haddrath, 2017).
  • Their sleek body allows them to swim through water with efficiency (De luliis and Haddrath, 2017)
  • They have a reduced fluid resistance (NAM et al, 2017)
  • Their fins, being tail flukes, help stabilize their body as they swim (De luliis and Haddrath, 2017).
  • Whales were first defined by the 18th century Swedish naturalist, Linnaeus, “as warm-blooded, four-legged animals that give birth to live young” (De luliis and Haddrath, 2017).
  • Whales have mammary glands to produce milk
  • They have short hair around their mouth and face of some species
  • They have similar internal anatomy and DNA to other mammals (De luliis and Haddrath, 2017) with the closest similar DNA being that of hippopotamus (De luliis and Haddrath, 2017).
  • Whales can deep dive into the oceans by holding their breath for long durations of time (De luliis and Haddrath, 2017).
  • Whales also have a low bone mineral density which allows them to have buoyancy control in deep water (NAM et al, 2017).

Classifications of Whale Cetaceans

There are two whale classifications that can help provide knowledge of how whales live and function in the ocean ecosystem, with past population evidence suggesting whales formally displayed both classifications. This provides more than just information of how whales are classified but also gives us information to classify whales in terms of which whales fall into each of these two classifications and how they feed to survive.

The two (2) separate groups of whale cetaceans are:

  • Toothed whales; and
  • Baleen whales (Fisheries & Oceans Canada, 2018).

Fossils 24 to 28 million years ago suggest whales had both baleen and teeth (De luliis and Haddrath, 2017).

Sperm Whale (Credit: Nosengo, 2009)

Toothed Whales

Toothed whales or “odontocetes” include sperm whales, beaked whales, beluga whales, killer whales, and narwhal whales (The Marine Mammal Centre, n.d.).

Two of the largest toothed whales are the killer whale and sperm whale species whose populations can fluctuate as a “K-selected species” in relation to their environment (Peterson & Carothers, 2013).

They also live long lifespans, have low birth rates, and have high maternal instincts (Peterson & Carothers, 2013).

Baleen Whale

Baleen Whales

Baleen Whales or “mysticetes” include gray, humpback, bowhead and blue whales with the blue whale being the largest whale in the ocean (The Marine Mammal Centre, n.d.).

To learn more about marine mammals, view, visit and/or sign up with The Marine Mammal Centre.

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Created By
Maria Lisa Polegatto


Created with images by Dan Meyers - "Gotta love whale tail. Here’s the last of three photos I’m uploading of a gray whale I spotted off the Oregon Coast near the town of Depoe Bay. I’ve tried whale watching with a drone before but this is the first time a whale and the volatile Oregon coast weather cooperated. I used an 8-stop ND/PL filter and a Mavic 2 Pro drone to photograph this magnificent marine mammal." • Francesco Ungaro - "untitled image" • Todd Cravens - "untitled image" • Flavio Gasperini - "Two humpback whales dance in front of our small boat as we head back to the Sea Shepherd vessel Bob Barker. I took this photo during Operation Albacore III in the Atlantic Ocean. Please consider donating to Sea Shepherd. For The Oceans!"