Seals Crowding Point Haulout

Richard Bangert &nbsp&nbsp The specially built float at Alameda Point cannot be seen under a resting pod of harbor seals on Dec. 29.  A cloudy sky revealed the seals’ coats’ array of colors.

Seals Crowding Point Haulout

As of Dec. 29, the number of harbor seals on the float at Alameda Point exceeded 70 on nine days, hitting a new record for December.  On Dec. 23, the number of seals on the float reached 80, a new record for a single day. Seals were packed so tightly that some were barely hanging onto the edges. The cramped conditions when the float reaches 70 seals in December and January can lead to bouts of slapping and shoving, as harbor seals prefer to have some space when resting.  

On Dec. 23, there were so many seals looking for a place to get out of the water and warm up at Alameda Point that 53 had to climb onto the rock wall known as Breakwater Island, another record.     

The seasonably colder water temperatures lead to a spike in the number of harbor seals making use of the float. Winter herring spawning in the vicinity also attracts greater numbers of seals. The central part of San Francisco Bay has the highest density of fish species throughout the year, according to the California Department of Fish and Wildlife, making the Alameda Point float uniquely convenient for the seals.

The specially built harbor seal float was deployed at Alameda Point in June 2016 and paid for by the Water Emergency Transportation Authority which built and operates the nearby ferry maintenance facility. It is the only known floating platform in the world built specifically for use by harbor seals, whose shoreline habitat for resting and giving birth will face growing impacts as sea level rises.   

 

Richard Bangert posts stories and photos about environmental issues on his blog at www.alamedapointenviro.com.