How long do they live? This one is a tough one, but some size distribution estimates indicate that Gray whales can exceed 75 years old [1].

Where are they found? Gray whales can be found in the Eastern and Northern pacific ocean. See figure 1.

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Figure 1. Range of the Gray whales.

What do they eat? Being baleen filter feeders, Gray whales eat really tiny creatures, such as amphipods and ghost shrimp that live on the sea floor [1].

What do they look like? They can grow to be 50 feet long and 80,000 pounds and they look like they are always smiling. See figures 2, 3, and 4.

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Figure 2. Gray whale.
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Figure 3. Okay, so this one looks a bit displeased, so I guess they are not always smiling.
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Figure 4. This one is definitely smiling.

How do they reproduce? Gray whales reproduce by sexual reproduction and give live birth. They reach sexual maturity between 8 and 11 years of age [1]. Reproductive senescence has not been documented that I can find.

How do scientists know how old they are? Some estimates have been based on waxy earplugs while others on size and lots of math, but as other estimates like this in sharks and whales has revealed – these are not the best methods for age estimation. There’s also one group studying the lifespan of gray whales through photographic evidence [2].

So what are we lacking? Reproductive senescence data and a non-invasive way to estimate the age of living whales. Mitochondrial genome information can be found on the NCBI, but no nuclear genome information is uploaded for Eschrichtius robustus.

Conservation status: After many years of over exploitation by the whaling industry, Gray whales were in serious danger. You see, they swim slowly and that makes them an easy target for someone who enjoys killing slow things. Now thanks to worldwide efforts to stop whale hunting, the Gray whale is listed as least concern on the IUCN website.

Please feel free to contact me if you would like to contribute to any species on this website.

  1. Animal Diversity.org. Gray Whale. Accessed 10/30/2016. http://animaldiversity.org/accounts/Eschrichtius_robustus/#ec2fdf04919d250dcdc5355aa3ffe1b5
  2. Weller, David W., et al. “GRAY WHALES (ESCHRICHTIUS ROBUSTUS) OFF SAKHALIN ISLAND, RUSSIA: SEASONAL AND ANNUAL PATTERNS OF OCCURRENCE1.” Marine mammal science 15.4 (1999): 1208-1227.