[Originally posted to MBA Student Oceanography Club (SOC)]
Elkhorn Slough is great sea otter habitat, and it’s one of the best places to see otters up close. The large group of otters we saw right off the beach where we launched our kayaks is particularly conspicuous, and consists only of males. This is remarkable because male otters tend to be territorial; they will establish territories in areas with lots of food and females, and chase away any other males that wander by. While hanging out in the male groups, however, they cease to be territorial and all get along. You'll frequently see males in the group napping and playing together. The groups also tend to be very dynamic. Otters will continually join and leave the group as they go to feed or travel to different areas, but there are regularly over forty otters present at one time.
That view has changed, however, after scientists realized that many territorial males spend part of the year defending their territories, and then spend part of the year with the male groups. Some have been known to swim over one hundred miles just to hang out with the guys! Scientists aren't really sure exactly why the males all hang out together, but it seems to serve an important social function. There are usually older and younger otters present together, and it may be an important way for young otters to learn about otter social structures and how to interact with other males.
For more fascinating otter facts, check out the following sites:
SORAC: http://www.montereybayaquarium.org/cr/sorac.aspx
Sea Otter Project: http://www.otterproject.org/
SORAC: http://www.montereybayaquarium.org/cr/sorac.aspx
Sea Otter Project: http://www.otterproject.org/
For
our first field experience we all participated in the beach clean-up,
which was a great way to start off SOC. I was pleasantly surprised by
how little trash we found, and pleased to keep what trash we did find
from entering the ocean. For photos of some of you keeping trash out of
our oceans (and enjoying the barbecue afterwards), scroll down to the
bottom of this post.
Because
many types of plastic float, they are easily carried by the currents,
and remain in the environment for a long time. For trash in the North
Pacific, this means that they are slowly but surely carried around by
the North Pacific Gyre. The gyre is a large-scale clockwise circulation
pattern that moves water west along the equator, swings north along the
eastern coast of Asia, loops back east about part-way between Hawaii
and Alaska, and finally turns back south along our coast. Because of
currents like these, trash from all over the world can end up on our
beaches (and likewise, our trash can spread around the world). In the
center of the gyre lies a large area with relatively little current.
Trash that makes its way here tends to stay put, and large amounts of
trash have aggregated there over time. This is commonly known as the
Great Pacific Garbage Patch, and recent studies indicate that millions
of tons of trash have concentrated in an area roughly twice the size of
Texas!
