Thursday, February 25, 2010

Canary Rockfish

[Originally posted to the Marine Photobank]

Canary rockfish on a rocky reef.


Description:
Rockfish of the genus Sebastes are commercially harvested along the North American Pacific coast, and are the basis for several important fisheries. Their low reproductive rates and slow growth make them vulnerable to overfishing.

Exposure Date:
12/28/2009

Gallery:
Marine Species of Concern

City/Region:
Seattle

State/Province:
Washington

Country:
United States


Download:
http://www.marinephotobank.org/secure/gallery-photo.php?photo_id=7098

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

Rockfish in California

[Originally posted to the Marine Photobank]

A rockfish resting on a ledge.


Description:
Rockfish of the genus Sebastes are commercially harvested along the North American Pacific coast, and are the basis for several important fisheries. Their low reproductive rates and slow growth make them vulnerable to overfishing.

Exposure Date:
8/9/2009

Gallery:
Marine Species of Concern

City/Region:
Monterey

State/Province:
California

Country:
United States


Download:
http://www.marinephotobank.org/secure/gallery-photo.php?photo_id=7097

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

Tuesday, February 23, 2010

Common Loon

[Originally posted to the Marine Photobank]

A common loon.


Description:
A common loon (Gavia immer) overwintering on the California coast.

Exposure Date:
11/04/2009

Gallery:
Marine Species of Concern

City/Region:
Monterey

State/Province:
California

Country:
United States


Download:
http://www.marinephotobank.org/secure/gallery-photo.php?photo_id=7102

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

Additional Comments:
shorebird, seabird, bird, Great Northern Diver

Black Oystercatcher

[Originally posted to the Marine Photobank]

A Black Oystercatcher.


Description:
A Black Oystercatcher (Haematopus bachmani) from the coast of Central California.

Exposure Date:
11/04/2009

Gallery:
Marine Species of Concern

City/Region:
Monterey

State/Province:
California

Country:
United States


Download:
http://www.marinephotobank.org/secure/gallery-photo.php?photo_id=7101

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

Additional Comments:
shorebird, seabird, bird

Western Grebe

[Originally posted to the Marine Photobank]

A Western Grebe.


Description:
A Western Grebe (Aechmophorus occidentalis) along the Central California coast.

Exposure Date:
2/13/2010

Gallery:
Marine Species of Concern

City/Region:
Monterey

State/Province:
California

Country:
United States


Download:
http://www.marinephotobank.org/secure/gallery-photo.php?photo_id=7103

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

Additional Comments:
shorebird, seabird, bird

Halibut in California

[Originally posted to the Marine Photobank]

A halibut on the sandy bottom.


Description:
Halibut are an important commercial and recreational harvested species along the North American Pacific coast.

Exposure Date:
11/11/2009

Gallery:
Marine Species of Concern

City/Region:
Monterey

State/Province:
California

Country:
United States


Download:
http://www.marinephotobank.org/secure/gallery-photo.php?photo_id=7100

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

Tuesday, February 2, 2010

Año Nuevo Elephant Seals

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


Elephant seals are amazing creatures.  It is easy to see them on the shore and imagine that they are slow and lazy.  Other than the brief brush ups among the males (see the video above), they didn’t seem to do much when we were visiting, but in reality they are well adapted for an extreme lifestyle.

For example, though they appear to laze on the beach for months at a time, they do so without eating or drinking any food or water.  Males can be on the beach for as long as three months, and may lose up to a third of their body weight during that time.  To make up for that lost weight,  elephant seals must be voracious and efficient eaters, so when it comes time to head to sea, they go right to the best fishing ground – in the middle of the Pacific north of Hawaii for females, and up near the Aleutian Islands for males – where they gorge on squid and fish.  The seals return to our coast twice a year, and may cover well over 10,000 miles in a year.

Each year they’ll spend 8-10 months at sea, 90% of which they are underwater.  They dive continuously, rarely spending more than five minutes at the surface between dives.  They even dive while sleeping, taking 15-30 minute naps without breathing.  While foraging, they can dive for almost two hours at a time, and reach depths of nearly a mile.  At those depths, the pressure is tremendous; any air in their lungs would quickly dissolve into their blood, causing major problems as it turned back into gas when they resurfaced.  To solve that problem, they actually exhale, completely emptying their lungs, before they dive.

Without air in their lungs, they have a host of other physiological adaptations that help ensure that they have enough oxygen so that they don’t pass out while they are under water.  For one, they have blood extremely rich in hemoglobin, the protein that binds oxygen and gives blood its red color.  Similar proteins in their muscles allow them to stock their tissues with large amounts of oxygen.   When diving, they also lower their metabolism, slowing their heart rate and stopping blood flow to the skin to reduce oxygen consumption.

With such intense feats of swimming and diving, it's no wonder that they like to relax when they come to shore.