Or why we should all love blue footed boobies.
Eastern Pacific Ocean Pasture Collapse Tracks Sardine Fishery Collapse
In 1948, the question of why the sardines on the California coast had disappeared was posed to legendary ocean biologist Ed Rickett, who was investigating the most famous sardine crash in history, which began in 1946.
He quipped, “They’re in cans!”
Ricketts was not only a biologist he was also the central character in John Steinbeck’s book Cannery Row which chronicled the steamy life of Ricketts, marine life, and the California coastal town of Monterey.
Today’s ocean scientists don’t think the answer was so simple, as sardine populations are known for following a boom-and-bust cycle. They point out that collapse of the sardines ocean pastures and plankton stocks that was triggered by a natural chilling of ocean waters was the principal cause. But they don’t deny that overfishing the sardines at the same time as the carrying capacity of their ocean pastures collapsed played a significant role in the mid-century crash.
Sardines and seabirds
Now it seems that the chilly Galapagos islands may lose one of thier most iconic beach species, the blue footed booby. In April 2014, a team of researchers from Wake Forest University announced that starving blue-footed boobies had virtually stopped courtship behaviour and breeding, putting the survival of the species in grave danger.
Researchers from University of California reported similar findings about another shorebird 2,000 miles from Galapagos. While conducting a survey of Mexico’s Natural Protected Areas, they discovered that the endangered California brown pelican was largely absent from its primary nesting grounds. Those found were malnourished and starving. Like the boobies, they had nearly stopped breeding.
Pelicans, boobies, and other seabirds depend on sardines and other small ocean pasture fish. This winter what is now reported as the largest die off of seabirds in the Pacific is happening with small pelagic seabirds like the Cassin’s Auklet dying by the millions.
Sardines lost in the 1940’s finally started coming back 40 years later but now they are collapsing again.
In the 1980s, sardines started to come back. and 20 years populations have shown cycles of decline and increase. Sardine biomass (a measurement of total adult sardine stock) was seen to peak in 2006-2007. It then began dropping about 8 to 14 percent every year — until 2011. A mild La Niña weather system developed in late 2010 through early 2011, and returned from late 2011 into 2012, lowering ocean temperatures and creating poor ocean pasture conditions reminiscent of the low pasture productivity and carrying capacity of the 1940s. The sardines lost 30 percent of their population, from 680,004 metric tons at the beginning of 2011 to 473,374 metric tons at the beginning of 2012.
A study watching offshore ocean pasture productivity and sardine populations conducted in 2011 concluded, “Imminent collapse is likely.” Researchers pointed to loss of plankton compounded by unsustainable fishing practices, including high catch limits and the fishing industry targeting and catching older, breeding-age fish. Yet the sardine managers increased the fishing quota. In 2011, the catch was ~11% of the total biomass. In 2012, that number grew significantly, with a total catch of 18% of the total biomass. In the 2012-2013 sardine year the population dropped about 30 percent, to a mere 333,268 metric tonnes. This drop is shown to be the second great sardine crash, and has been compared to the first notorious crash of the late 1940s and 1950s.
In late 2013, federal fishery managers took heed of the downward trend, setting 2014 catch levels 33 percent below what they would have been under the previous management plan. The most recent formal Stock Assessment Review, conducted in March 2014, projected a slight increase in sardines between 2014 and 2015. However, scientists remain worried, and the 2014 projections have yet to be proven. According to a November 2014 Oceana press release, the Pacific sardine biomass is at the lowest level in two decades, with no clear signs of recovery. Yet the Pacific Fishery Management Council voted to increase the harvest rate by 33 percent, a move that Oceana’s Pacific project manager and senior scientist Ben Enticknap called, “a blow to long-term sustainable fishery management.”
The Eastern Pacific is one of the most dust depleted oceans on this blue planet.
What’s dust got to do with sardines and seabirds? Just as pastures on land depend on a vital resource, rain, that comes to them in the wind ocean pastures depend on dust that comes to them on the wind. Our high and rising CO2 in the air is however producing Global Greening. As the lands become greener and enjoy better ground cover this produces a deadly result for ocean pastures.
More grass growing means less dust blowing.
Along with the rise in CO2 the vital source of dust for the Eastern Pacific is also the subject of a highly effective soil conservation effort in Gobi desert of China and Mongolia called the Great Green Wall.
Don’t despair here is the good news – we can bring back the fish
The ocean pastures are so resilient they will come back to health in a season or few with a very little help from us. All they need is a little dust in the wind … or from our human hands … a tiny portion of that same dust delivered to replenish that which we are denying the ocean pastures. With our help ocean plant life that is standing ready will convert billions of tons of ocean killing CO2 into ocean life itself. Being good dusty shepherds of ocean pastures will cost a tiny fraction of the great green wall and it will bring back the fish putting a billion additional fish on the plates of hungry people around the world.
Read more here at Bring Back The Fish.