What You Otter Know About Sea Otters

Hello again, wonderful readers! As you may have guessed from the title, this entire blog post is going to be about awesome otter facts that I read about this week. I did do some work this week other than otter research, especially with the HFSS program, but I'll talk about that and more about antennas next week. This week is devoted to otters!

- Probably the most useful information that I found for my project is that an otter's neck is wider than its head, so it would be extremely difficult to put a comfortable collar on the otter. Also, observers have seen that an otter will frequently chew off most objects placed on their limbs, such as RF trackers, so we may have to get creative with where and how the tracking device will stay on the otter.

- There are several different kinds of otters. There are actually a lot of differences between the two different otters that I've read about, the sea otter (Enhydra lutris) and the European river otter (Lutra lutra). River otters can be found around Europe and Asia, and they live mostly on land and by fresh water, whereas sea otters are found primarily on the Western coasts of North America and Southern Alaska.

- Sea otters can live their entire lives in the sea! They can even give birth in the water; in fact, they prefer it to giving birth on land.

- A common nickname for the sea otter is "the old man of the sea," because of their bristly face and prominent whiskers that make them look like they have an old man's beard. Additionally, the sea otter has a long history of exploitation and hunting for their pelts, especially in the Alaskan and Californian regions, where it got so bad near the end of the nineteenth century that it was referred to as the "Soft Gold Rush."

Sea otters don't mind using their belly as a table

- There is a reason why sea otter pelts were valued so much. Their pelts have the thickest fur of any mammal at 110,000 hairs per cm². Also, their skin is very loose-fitting on their bodies and stretchy. This is all because of how important it is for them to groom themselves. Because of their extremely thick fur, they can keep air-bubbles trapped in the fur to help keep them afloat. However, over time they lose the air-bubbles to water soiling, so they have to frequently groom themselves to make sure they can stay afloat with relative ease.

- As many of you already know, sea otters will often wrap themselves in kelp and even hold hands with other otters so as not to float away while they sleep.

- Sea otters eat a ton! To keep up their body temperature and metabolism they will often eat 30% of their body weight every day. In order to obtain enough food, most sea otters will spend anywhere between 25% and 50% of their days foraging for food. If you weren't convinced that otters are awesome by now, please know that sea otters are the only mammals other than primates that use tools! They use rocks in a variety of ways in the pursuit and consumption of food, such as bashing clams against rocks held on their stomachs.

- Most otters aren't very happy about pollution, but some otters have taken to tearing open aluminum cans found on the bottom of the sea because more often than not they are the homes of small octopuses!

A mother and her pup

- I did promise to talk about why sea otters are especially sensitive to their environment and pollution. Sea otters are vulnerable to biomagnification, which many of you may remember from AP Bio. Biomagnification occurs when certain toxins that are present in small concentrations in the tissues of organisms low on the food chain become more present in higher trophic levels of the food-chain. Therefore, organisms higher on the food chain are more vulnerable and harmed by this effect. A toxin in boat paint called Tributyl tin has been of particular concern to otter conservation efforts because it is commonly found in the tissues of the invertebrates the sea otters eat.

- I am sorry if this ruins anybody's perceptions about sea otters, but sea otters are far from monogamous. A single pair of sea otters will almost always only mate one time. Female otters are polyestrous, which means that they can have cubs multiple times throughout the year, and many times they will do so. Also contributing to the lack of monogamy is the tendency of males to travel much greater distances than females, who are more likely to stay in the same area their entire lives.

I think that's enough about sea otters for the day. I have enough additional cool facts about otters to fill an entire other blog post (all sea otters that have been observed are right-handed!), but I don't want to be a crazy otter guy. If you're not a biology or ecology person, look forward to next week, where I will probably talk a lot about different antennas, how they work, and how they may or may not apply to my project.

In the meantime, if you want to know anything else about otters or have any questions, please let me know in the comments. I'd love to hear from you guys! See y'all next week.

Don't you want a pet otter now?

Sources:
Love, J. A., Sea Otters (Whittet Books, London, 1990)
Mason, C. F., and S. M. Macdonald, Otters: ecology and conservation (Cambridge University Press, Cambridge, 1986)

Pictures:
http://scienceillustrated.com.au/blog/wp-content/uploads/2012/03/sea-otter.gif
http://i.telegraph.co.uk/multimedia/archive/01923/otter_1923262i.jpg
http://25.media.tumblr.com/da9cd1da9aedd72e359d8b403946cbe5/tumblr_mqnucyG4DS1s15skfo1_400.gif