What's the difference between a seal and a sea lion?

Just as I looked up, it dove under. What was it? I watched for a long time and then movement about 30 feet south caught my eye. I turned, and again, missed it. Just the movement of swirling water. 

Determined, I continued to watch. Finally, a round head popped up in front of me about 30 feet out, eyed me for a a couple of seconds only to dive below again.

Now I knew it was either a seal or sea lion. But not quite sure, which one. I needed a longer look. 

Watching any animal in the wild is thrilling and it's even better when I can identify them. Some of my favorites are in the marine mammal family. Maybe because I love spending time on the beach. To me these sea creatures are so mysterious and wonderful. Living in the deep waters of the ocean, more comfortable in water than on land. Diving and swimming instead of walking and running.

So whenever I see a marine mammal, I'm instantly intrigued, tirelessly watching and waiting for a second, third or fourth glimpse.

Sometimes it's a very long wait, like this time. Some of these animals can stay under water for up to 20 minutes. 

Finally, his head popped up. And I knew it was a Harbor seal! (pictured above) My first clue was that he was earless. My second was his spotted body.   

Persistence has paid off. Over the years I've had the good fortune to see a variety of whales, sea lions, walruses and seals in the wild. (Waterfowl are cool, too. I'm still learning to identify all the different types of ducks.) 

California sea lions and Harbor seals are common to the Salish Sea--my area of the world. Although I live more than a mile from a bay in the Puget Sound, I often hear a raft of California sea lions barking. These big guys winter here, hauling out on a log boom near the shore.

So when I first started paying attention to seals and sea lions, I thought they were all sea lions, because they looked so similar in the water. Eventually I learned the difference.

Here are a few distinguishing characteristics. 

  • Sea lions have a more sloped head compared to the round head of a seal.
  • Seals are typically smaller than sea lions with slug shaped bodies. Sea lions are long and sleek.
  • Both are extraordinary swimmers and very intelligent. In aquariums their antics are entertaining, and always a big hit with crowds. 
  • Seals are slow and laborious on land, bouncing and wiggling to their spot. Their front flippers are small and weak so not that helpful. Sea lions are better able to walk on land, using their large front and back flippers to maneuver. They are able to rotate their hind flippers, which allows them to walk on "all fours." 
  • Colors and fur vary depending on the type of seal or sea lion. In the Pacific coastal waters, California sea lions and Harbor seals are most common. These sea lions are brown compared to Harbor seals, which are lighter in color, covered in dark irregular-shaped spots. 

So next time you see one, you can wow your peeps with your new-found knowledge!

Sometimes you just get a glimpse, so challenge yourself to know the characteristic of other similar wild animals. Here are a few to get you started.  

  • wolf vs. coyote
  • grizzly bear vs. black bear (think cinnamon black bear)
  • beaver vs. muskrat
  • elk vs. deer
  • weasel vs. mink
  • pika vs. rabbit
  • cougar vs. bobcat

Happy wildlife watching!

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