There’s a life-and-death battle playing out just beneath the waves around Catalina and, for that matter, most of Southern California.
The sea lions are losing and a plant native to Asia is making matters worse.
In case you’ve missed it in the local and even national and international news, huge numbers of sea lion pups have been turning up dead or near death on beaches around the southland, including here at Catalina.
There’s a life-and-death battle playing out just beneath the waves around Catalina and, for that matter, most of Southern California.
The sea lions are losing and a plant native to Asia is making matters worse.
In case you’ve missed it in the local and even national and international news, huge numbers of sea lion pups have been turning up dead or near death on beaches around the southland, including here at Catalina.
According to an Associated Press report, nearly 2,000 of the animals have been rescued since January and countless others have perished.
As with any such issues involving the environmental, the reasons are many and complex.
Part of it involves warmer-than-normal water temperatures brought on by a late-season El Nino. But there is another reason as well.
Local researcher and oceanographer Jon Council said the storms of last summer, specifically the tremendous surge generated by Hurricane Marie in August, had the effect of devastating one of Catalina’s most important ecological species, the giant kelp or macrocystis pyrifera.
During those tumultuous storms, not only were some of our local marine facilities and even shore-side infrastructure destroyed, but vast populations of the giant kelp around the Island were torn from their holdfasts, leaving precious few viable stands.
Giant kelp is not only one of the cornerstones of the local food chain—being foodstuffs or hiding places for innumerable species—but its absence also directly impacts the feeding habits of seals.According to Council, one of the ways seals use the kelp is as cover during their hunting expeditions.
“They use the kelp like duck blinds and dart out into anchovies and smelt. Without the kelp, they don’t have that cover,” he said.
This means that sea lions have to work extra hard to get to the bait balls. While the adults are more or less able to adjust to the situation, “the pups just aren’t that fast.”
Adding insult to injury is the fact that some species, such as smelt, lay their eggs in the fronds or leaves of the giant kelp.
So not only are the smelt harder to catch for the young seal pups, but with fewer smelt being born, there fewer of them to catch.
So it would stand to reason that simply waiting for the giant kelp to grow back will solve the problem.
Unfortunately, the kelp fly in the ointment involves the presence of an invasive species of sea growth from Asia known as Sargassum horneri.
This species grows rapidly and has the effect of “shading” the ocean shallows, creating less-than-ideal conditions for the young kelp plants to gain a foothold.
In other words, as long as the Sargassum is occupying that niche, the kelp doesn’t stand a chance.
According to local biologist Dr. Bill Bushing, the Sargassum first made its appearance in Long Beach approximately 11 years ago. Scientists suspect the international shipping traffic in the harbor is the likely culprit.
Since then, it has proliferated and, of course, made Catalina part of its domain. (Ironically, according to Dr. Bushing, the species is on the decline in Japan).
As far as the prognosis for our adorable seal pups and their fellow denizens of the deep is concerned, Council said the jury is still out.
“There are tons of animals that feed on (the kelp). How are they being affected?”
While such calamities have no doubt occurred numerous times in the past, Council said this particular episode is particularly troubling.
“It’ll be interesting to see what the ramifications are,” he said. “There are tons of animals that feed on (the kelp).”
“It’s the worst I’ve ever seen in 21 years,” he said. “In 21 years I’ve never seen this.”
