Sea Lion Strandings Climb, Scientists Still Stumped

Megan Gannon, News Editor

Date: 17 April 2013 Time: 03:12 PM ET

Scientists still don't know why nearly 1,300 sickly sea lions have beached themselves on the shores of southern California since the beginning of the year. However, they think some weird oceanic phenomenon may be blocking off the sea lion pups' source of food, scientists reported today (April 17).

The stranded sea lions — mostly pups born last summer — are typically turning up alive, but severely emaciated, some weighing less than 20 pounds (9 kg) when they should be well over 50 pounds (22 kg), marine officials say.

The National Oceanic and Atmospheric Administration (NOAA) declared an "unusual mortality event" last month in light of the spike in strandings. Since the beginning of the year, 1,293 sea lions have washed ashore from San Diego County to Santa Barbara County. That's more than five times higher than the region's historical average of 236, averaged from the same period of time (January through April) from 2008 to 2012, said Sarah Wilkin, NOAA's marine mammal stranding coordinator for California.

Continued:  http://www.livescience.com/28807-sea-lion-strandings-climb.html

Large numbers of emaciated Sea lion pups washing ashore in California

Sea lion ‘Unusual Mortality Event' in California

April 2013. After several weeks of unusually high levels of sea lion strandings and high numbers of dead sea lions washing up on the beaches of Southern California, the local authorities have declared ‘An unusual mortality event' (UME).

Beginning in January 2013, increased strandings of California sea lion pups have been observed in Southern California (Santa Barbara, Ventura, Los Angeles, Orange, and San Diego Counties). The area with the highest reported stranding rates is currently Los Angeles County, followed by Orange County, and strandings are increasing in San Diego County.

300% increase

The increase of sea lion strandings continues and has intensified over the last few weeks. Live sea lion strandings are nearly three times higher than the historical average.

Emaciation and dehydration
Currently, the UME is confined to young of the year (born summer 2012) California sea lions. Consistent findings in the sea lions are emaciation and dehydration with most animals very underweight for their age. The California Marine Mammal Stranding Network continues to rescue and rehabilitate animals.

As part of the UME investigation process, an independent team of scientists (investigation team) is being assembled to coordinate with the Working Group on Marine Mammal Unusual Mortality Events (Working Group) to review the data collected and to determine potential next steps. The group will focus on the immediate response and develop the investigative plan.

Continued:  http://www.wildlifeextra.com/go/news/sea-lion-california.html