West Coast Marine Ecosystem May Be Crashing

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Now you see them, now you don’t. And when you don’t see sardines, the whole web of ocean life falters. (Photo by Juuyoh Tanaka/Flickr)

This is not a drill. A profound crash in the web of marine life in West Coast waters is under way, and may have gone on for two years already. Current observations that are setting biologists’ hair on fire include:

• the sardine population from California to Canada is vanishing — the worst crash in generations;
• starving sea lion and seal pups are washing up on California beaches in unprecedented numbers for the second straight year;
• brown pelicans in the same area are showing signs of starvation and have not raised any chicks for four years;
• a massive bloom of toxic algae in Monterey Bay is poisoning sea lions, fish and shellfish, and poses a threat to human health.

Sardines are a volatile species, and the fisheries based on them are famously boom-and-bust in nature. Among other things, sardines respond to the Pacific Decadal Oscillation, a periodic (10-20 year) variation of sea-surface temperatures that is the northern counterpart of the Southern Oscillation, one phase of which is better known these days as El Nino. While is is true that the PDO is now in its negative phase, bringing to the surface cold upwelling water that sardines hate, marine biologists are not convinced that the PDO straight from the source can account for the drastic reduction of the sardine population that they are seeing.

The sardines’ absence is radiating through the ecosystem. Only plankton are below them in the food chain, and virtually everything else in, on and near the ocean is above them and depends on them; hence the starving pelicans and seals.

The toxic algae bloom in Monterey Bay is a separate problem but it is affecting the same ecosystem in what some experts are calling a perfect storm. Wildlife officials are dealing with dozens of convulsing sea lions and dead sea birds — some of which actually drop out of the sky — and are watching helplessly as the toxicity of Monterey Bay increases off the charts. Because of the toxins, health departments are warning against human consumption of the area’s shellfish, crabs, anchovies or sardines — that latter warning just in case anybody catches any sardines, which is not happening.

The storm becomes even more perfect when you add the effects of ocean acidification, which is decimating the shellfish populations (and industries) of the Pacific Northwest and Canada. [see Billions of Shellfish Die as Ocean Turns to Acid] And if, as some are suggesting, one of the factors turns out to be spreading radiation from Japan’s defunct Fukushima nuclear power plant, well then the storm is more than perfect.

Like an unbalanced bicycle rider. an unbalanced ecosystem can wobble back and forth for a while without crashing. It can even recover. Whether what we’re seeing on the Pacific Coast is a wobble or a crash will be evident quite soon. But in either case, the effects will be dire and long lasting.