Battle on the Nine

Wednesday, December 16, 2015 Unknown 0 Comments

Several weeks back I was able to join my good friends at SD Expeditions on a trip out to the Nine Mile Bank off the coast of San Diego, CA. The Nine as most call it is a high spot situated nine miles off the coast.

We were out to find and photograph some blue, mako or hammerhead sharks. The blues and makos are the usual suspects but with elevated sea surface temperatures this year due to the current El Nino event hammerheads have been around.

Although the warm water has been good in the sense that new exotics such as hammerheads, blue marlin, wahoo, mantas and whale sharks have been around it has also forced much of the normal life north to cooler waters. As we motored around the water was pretty void of life. No whales, bait fish, marine mammals or an abundance of sunfish (Mola mola) that can often be found on the Nine.

But as we searched around we found a large amount of birds dropping down to feed. It was then we saw a sea lion thrashing around and as we got closer we saw the fins of a mola mola.

Mola's are the world's largest bony fish and can reach 15 feet across weighting nearly 5000 pounds. Mola's don't have a great deal of predators due to their incredibly rough/tough skin and their massive size as adults. As juveniles mola are prey for  bluefin tuna and mahi mahi (dorado) but as adults mola are predated on by orcas, sharks and sea lions. In Monterey, California sea lions are regularly seen hunting mola for sport where they will rip the fins off molas but won't consume the meat.



A Mola mola, the world's larges bony fish


The number one threat to molas off the coast of California is their interaction with the drift gillnet fishery where they become entangled in the nets.


A gillnet scar on the face of a mola



As we slipped into the water we were sure to stay back and observe from a distance but as we watched this epic event unfold the sea lion became more and more comfortable with us and seemed to actually bring the mola closer to us.

The sea lion begins to break the mola's skin


Sea lions are notoriously smart. And, when you consider the anatomy of a mola (photo below) you realize that the sea lion was very strategic about where and how he entered the mola. With such tough skin and bony underparts the entry point makes sense. 


Mola mola anatomy. Credit: Gregory, W. K. & Raven, H. C. (1934)


This past year has been extremely hard on California sea lions with limited prey causing thousands of them to die or become stranded. New research suggests many of the newer standings could be due to sea lions eating crabs that have consumed a toxic algal bloom. But anyways, with limited food availability sea lions have had to take advantage of all the prey they can find, including molas. 





By the time we left the mola was chest deep in the mola pulling out the remainder of the guts and stomach. I have been asked several times now how I could watch or photograph this event. And while I do love molas the event would have taken place whether I had been there or not and my job is simply to document what goes on in the ocean. 

For more of my work you can check out www.ralphpace.com