It’s unusual because this is the season when sea lion pups flourish. Instead they’re struggling ashore in starved, emaciated conditions, if they’ve managed to stay alive. Scientists say almost half the sea lions born this past winter have died.
When they get too thin, they’re forced to go ashore for sun because they can’t stay warm in cool waters. All the concerned marine biology scientists are scratching their heads. Some have commented on how this sort of mortality rate is usually predictable according to atmospheric or oceanic conditions.
But there are none of the obvious tell-tale signs that could have predicted this high occurrence of seal pup mortality.
“They’re clearly not getting enough food,” said Victoria Harris, Interim Executive Director with the California Wildlife Center. Yet another scientist claims there are sufficient squid and sardine populations for them off the coast of California.
Scientists seem to be determined to get to the bottom of this marine life tragedy. “Marine mammals are sentinels of the eco system,” stated Victoria Harris, of the National Oceanic and Atmospheric Agency (NOAA).
The NOAA publicly announced that they considered radiation unlikely as the cause, but it wasn’t ruled out.
How radiation could be the primary causal event
Japanese marine scientists have announced extremely high radiation reading in sea water collected off Japan.
The New York Times article, “Fukushima’s Contamination Produces Some Surprises at Sea” published September 28, 2011 contained information from scientists about extremely high amounts of radioactive cesium 137.
The extremely high readings recorded at different times indicated that cesium 137 was rising, and at that time in 2011, more radioactive material was continuing to leak into the ocean.
That article registered concern over the high amounts of radioactive material, but claimed at that time the ocean was diluting the radiation levels low enough to prevent humans from being harmed directly.
Of course, California sea lions are a long way off from the Japan coast, but different currents and eddies could spread a continuing accumulation of radioactive contamination farther out into the ocean from Japan.
Even tuna caught off the California coast have been found with higher than normal traces of cesium 137 from the Fukushima disaster in May of 2012.
An unpublicized cause of death for seal pups is domoic acid, produced by toxic algae bloom. It causes seizure and death in California sea lions. Domoic acid is a neurotoxin produced by a few specific types of harmful algae blooms among the phytoplankton on the ocean’s surface.
Often this results in what’s been termed “Red Tide” that kills off lots of marine life.
Here’s where I’m going with this. Phytoplankton is easily corrupted. Although it’s involved with providing well over half the earth’s oxygen through the process of photosynthesis, excessive UV rays coming through ozone layer openings do damage them.
So now we have a 2011 report from researchers at the Tokyo University of Marine Science and Technology which stated that Fukushima’s radioactive cessium 137 has contaminated ocean plankton. Plankton is the first food within the marine life food chain.
Professor Takashi Ishimaru, said the plankton were heavily contaminated because sea currents continuously carried contaminated water southward from the nuclear plant. There you have it. Radioactively contaminated plankton.
If it doesn’t produce a form of domoic acid from that damage, it goes up the food chain to larger fish and sea mammals. Remember that quote from earlier in this article: “Marine mammals are sentinels of the eco system.”
If not directly from radioactive contamination, which has not been ruled out since some Fukushima radioactive debris has washed ashore on the west coast, then the indirect consequences of radioactive plankton could be at the bottom of this seal pup tragedy.
Sources for this article include: