Tuesday, November 9, 2010

Hanging with the guys.

[Originally posted to MBA Student Oceanography Club (SOC)]

A Raft of Kayaks
Paddling in Elkhorn Slough was so much fun!  We got a bit of a workout going against the tide at first, but it was worth it to see the wetlands.  Elkhorn Slough is a remarkable place, and I'm always amazed by the incredible wildlife I see whenever I visit.  Our kayak trip was no exception; we saw jellyfish, pelicans, bat rays, seals, sea lions and of course all the adorable sea otters.  Scroll to the bottom of this post to see photos from our trip.

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.
A Raft of Otters
Scientists used to think that the all the individuals gathered at Elkhorn Slough and similar male-only groups were the otters that weren't able to establish their own territories.  Male groups tend to occur near the ends of the Southern Sea Otter's range (Elkhorn Slough is near the northern limit of the Southern Sea Otter's range), and they believed that otters continually chased out of other otters' territories would eventually wind up pushed to the edge of the range where they were forced to gather together.

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. 
Swimming Sea Otter
Otters are fascinating creatures, and we are still learning a lot about them.  The aquarium's Sea Otter Research and Conservation program (SORAC) actively monitors the local otter population, researches otter behavior, and rehabilitates injured and abandoned young otters (raised with the exhibit otters as surrogate mothers).  In fact, Elkhorn Slough is such good habitat that SORAC reintroduces its rehabilitated otters to the wild there.  Many of the aquarium’s graduates have gone on to live very productive lives, and researchers regularly head out to the slough to see how they are doing.

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/
Sleeping Sea Otter

Tuesday, October 5, 2010

How many albatrosses did you save today?

[Originally posted to MBA Student Oceanography Club (SOC)]

Plastic Bag on Beach
An urchin carries a plastic fork.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.

We rarely think about the impact that trash has on the oceans – too often out of site means out of mind – but our garbage is a serious problem for life in the sea.  Trash, and plastics in particular, entering the environment can have numerous negative impacts on ocean life.  Discarded fishing line and six-pack rings can tangle and strangle birds, mammals, fish and other creatures.  Leatherback turtles may mistake grocery bags for jellyfish and slowly starve to death as they fill up on indigestible plastic.

Plastics in the stomach of a dead Laysan Albatross Chick
Laysan Albatrosses, too, confuse plastic for food. Flying fish frequently lay their eggs on floating bits of plastic, and the albatrosses swallow the items to ingest the eggs.  This isn’t too big of a problem for the adults, since they can regurgitate large items that they can’t digest.  Their young, however, lack the ability to regurgitate large items.  Like the leatherbacks, they may starve to death while their parents slowly fill them up with plastic.  Each piece of plastic you picked up might have saved and albatrosses life!

Even more insidious is the plastic that slowly breaks down.  We tend to imagine that plastics do not degrade.  That is certainly true of plastics sitting on our shelves or moldering in a landfill, but in the dynamic ocean, exposed to wind, waves and sun, many plastics break-down and degrade.  For most types of plastic that means that they are ground down into tiny particles no larger than the smallest plankton.  For other plastics, that means degrading into chemicals that dissolve in the water and may be toxic.  Either way, it is potentially detrimental for organisms living in the water or feeding on plankton.

Map of North Pacific GyreBecause 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!

Ironically, floating trash has also helped us better understand ocean currents.  In 1990, a shipping container filled with Nike shoes fell off of a freighter, releasing 80,000 sneakers into the North Pacific.  Shoes began periodically washing ashore along the West Coast of North America, and an enterprising oceanographer named Curtis Ebbesmeyer realized that by tracking shoes and other floating items lost from ships (collectively known as flotsam) we could learn about ocean circulation.  Following the Nike shoe spill, Dr. Ebbesmeyer continued tracking flotsam, including a large spill of bath toys that have spread across the Pacific, passed through the Arctic Ocean, and finally into the Atlantic Ocean.  If you ever visit the Atlantic coast and find a wayward rubber ducky washed ashore, check it out.  It may have travelled half-way around the world over the past two decades:

Dr. Ebbesmeyer displays some of the bath toys he has tracked as they drift around the world. Thousands of rubber ducks to land on British shores after 15 year journey
Read more: http://www.dailymail.co.uk/news/article-464768/Thousands-rubber-ducks-land-British-shores-15-year-journey.html

You can learn more about plastics in the ocean and the Great Pacific Garbage Patch by  visiting some of the links below:
http://www.projectkaisei.org/
http://www.greatgarbagepatch.org/

Friday, August 13, 2010

Sunflower Sea Star and Anemones

[Originally posted to the Marine Photobank]

A sunflower sea star among plumose anemones.


Description:
A sunflower sea star (Pycnopodia helianthoides) explores a rock covered in giant plumed anemones (Metridium farcimen) along the California coast.

Exposure Date:
8/9/2009

Gallery:
Photo Contest 2010

City/Region:
Monterey

State/Province:
California

Country:
United States


Download:
http://www.marinephotobank.org/secure/gallery-photo.php?photo_id=7379

Copyright Statement :
Image may be used for non-commercial and media purposes only. Credit should state, "Gerick Bergsma 2010/Marine Photobank."

Longnose Hawkfish

[Originally posted to the Marine Photobank]

A longnose hawkfish.


Description:
A longnose hawkfish (Oxycirrhites typus) perches atop a plating coral (Montipora sp.).

Exposure Date:
2/18/2010

Gallery:
Photo Contest 2010

City/Region:
Monterey

State/Province:
California

Country:
United States


Download:
http://www.marinephotobank.org/secure/gallery-photo.php?photo_id=7380

Copyright Statement :
Image may be used for non-commercial and media purposes only. Credit should state, "Gerick Bergsma 2010/Marine Photobank."

Saturday, June 5, 2010

Snorkel Safari


[Originally posted to MBA Student Oceanography Club (SOC)]
For our last field experience, we went snorkeling in Monterey Bay and had a blast.  We enjoyed great weather and explored the kelp forest and the rocky bottom areas near San Carlos beach.  My favorite part of snorkeling is seeing all the incredible creatures that live near our coast.  Here are just a few of my favorites that we encountered during our swim.

Brown Turban Snail Brown Turban Snail:  These little guys live in a world of algae.  We found them cruising along in the kelp (giant brown algae) where they eat microscopic algae growing on the kelp’s surface.  As though that weren’t already enough algae in its life, the color of the snail in this photo comes from red algae that cover its shell.  Learn more about them at:
http://www.montereybayaquarium.org/animals/AnimalDetails.aspx?id=781029
Bat Star Bat Star:   Bat stars come in a lot of different colors, and are always fun to spot.  We saw lots of them cruising the sandy bottom, where they act as nature’s vacuum cleaners, scavenging algae and dead animals it finds along the way.  Learn more about them at:
http://www.montereybayaquarium.org/animals/AnimalDetails.aspx?enc=n3f4wm...
Sheep Crab Sheep Crab:  Sheep crabs are in the spider crab family, and can grow quite large.  We found this sizable fellow ambling over rocks not far from shore.  Crabs this size can inflict a serious pinch, so I was sure to keep my fingers clear while I snapped this photo.  Learn more about them at:
http://www.montereybayaquarium.org/animals/AnimalDetails.aspx?enc=VsGX+L...
Sunflower Star Sunflower Star: The giant sunflower star is one of the kelp forest’s top predators, and the hordes of tube feet under its many arms allow it to move quickly, often sending its prey scrambling for cover.  We found this one in the open on the side of a large rock, but within minutes it had squeezed itself into a crevice where it was barely visible.  Learn more about them at:
http://www.montereybayaquarium.org/animals/AnimalDetails.aspx?enc=VsGX+L...
Opalescent Nudibranch Opalescent Nudibranch:  I found this beautiful sea slug crawling among the algae-covered rocks, where it was undoubtedly looking for hydroids or small anemones to eat.  The opalescent nudibranch is capable of transferring the stinging cells of its pretty to its own skin – a formidable defense that it advertises with is bright colors.  Learn more about them at:
http://www.montereybayaquarium.org/animals/AnimalDetails