Shellfish Continue To Wither
Whether they remain part of this blue planets ecology is up to us
For shellfish it is the first moments of life that crystallize the whole of their life
Our trillion tonnes of fossil fuel/fool age CO2 already emitted has made a tiny deadly shift in ocean chemistry and shellfish biology
All is not yet lost but the only hope for shellfish and most of ocean life on this blue planet is to restore the ocean ecology to historic health.
A multi-decade study of shellfish on the most western tip of the continental United States has long been reporting on the disappearance of shellfish from its inter-tidal rocks. Now part of that research, just published in the Journal Global Change Biology, has revealed how it works at the microscopic level. One reason for the shellfish apocalypse is increasing ocean CO2, it is weakening the structure of mussel shells along the West Coast.
Mussels like all shellfish start life as microscopic drifting larvae. For their first few days of life they use the small amount of nutrient left over from their eggs to begin their most vital process of harvesting calcium out of the sea water. They must use that calcium to make their first bit of shell. It’s a vital and delicate process of crystallization of the calcium into its carbonate/calcite form. Here’s a link to a paper from 2014 reporting on the crisis of thinning shellfish shells.
The nature of mussels is to grow long, cylindrical calcite crystals in neat and repeatable rows. This well-organized form gives their shells a seed bed that will produce and sustain over the years to come strength and hardness, something they must have as they live attached but battered in the wave tossed tidal zone. Tragically as detailed in a new study, published in the journal Global Change Biology, that geometric consistency, strength, and resilience is no more.
“What we’ve seen in more recent shells is that the crystals are small and disoriented,” study leader Sophie McCoy, said in a news release. “These are significant changes in how these animals produce their shells that can be tied to a shifting ocean chemistry.”
Her team of scientists analyzed the micro-structure and mineralogical composition of California mussel samples from Tatoosh Island off the coast of northern Washington. They compared the mussels found today to shells going back to the 1970s, as well as to mussel fossils from the area going back several thousand years.
For thousands of years the structure of the mussel shell crystals remained consisted, strong, hard, and resistant to damage but suddenly over just the past 15 years mussel shells have changed. Instead of large hard, strong, well-organized crystalized shells their shell structure has shifted to be made up of tiny disorganized crystals of calcium carbonate. This new form of shell is far less resilient and as a result the mussels are being battered out of existence in wave tossed habitats.
While many hasten to lable this a feature of ‘ocean acidification’ that’s a simplified climate change meme that is misleading and leads to argumentative debate. What is really happening is about very slight alteration of the solubility constant of vital minerals, especially calcium and magnesium.
When the micro-mussel makes its first shell it accumulates and lays down layers of calcium carbonate which as it grows it directs into a highly organized structure. Think of this as making a building out of blocks, the larger and more perfectly organized the blocks are the stronger and longer the structure will stand. For a human structure think of the durability of the ancient pyramids with that of mud huts.
Shifting ocean chemistry ever so slighty is shown to be incredibly deadly
Chemical analysis done in this research shows modern mussel shells feature increasing amounts of magnesium. Magnesium and calcium are often associated in living systems. This shift in the ratio of calcium and magnesium is clear evidence that their biochemistry has been dramatically altered by the ocean’s very slightly changing acidity/ mineral solubility. The increase in magnesium levels in the shells is held to be responsible for the dramatic, and deadly, changes in the mussel shell mineralogy.
McCoy first began investigating California mussel shell structure in 2009 when, soon after she began working toward her doctorate, she noticed stark visual differences between older and more recent shells. Her doctoral work was within the lab of the great ocean ecologist Timothy Wooten at the University of Chicago who has for decades nursed the multi-decadal study of the intertidal ecology of Tatoosh island.
“My job was to slice mussels in half and drill out the shell for isotope measurements, and by chance I noticed that older shells looked completely different,” she said. “They were twice as thick, massive and took twice as long to cut. Eventually, we found that this was true for other older shells found at various sites throughout the region. It was sort of by accident. We could see the shells were changing, but we weren’t exactly sure what was going on.”
“When there’s not a clear geometric pattern in the skeleton, the bond strengths become more variable, and that’s what we’re seeing in modern shells,” McCoy said. “They’re not being organized.”
If such changes were to take place of very long time frames, millenia instead of decades, the mussels might well be able to adaptively evolve, display the power of ontogeny, and survive.
Large Scale Ocean Ecology Restoration Is The Only Hope
The oceans that cover 72% of this blue planet are the most potent and powerful, and perhaps the only, means this planet has to safely regulate CO2. It has always been so. The way the oceans control CO2 in both seas and the air is through the power of ocean photosynthesis. That’s ocean plant life. The plants that dominate our oceans are the tiny nearly microscopic drifters, the plankton. The amount of living plant-life in the oceans is many times the amount of plant life on all of the lands of the Earth.
The ocean plankton has been seen to be diminishing in a cataclysmic collapse over the past 50 years. Today there is 40-50% less ocean phyto-plankton. The loss of the plankton, Natures most potent and powerful means to control CO2 is in lock step with humanities fossil fuel/fool age folly. The trillion tonnes of fossil CO2 we have emitted has disrupted not just the ecology and biology of the shellfish that occupy the tiny fraction of 1% of the oceans that are the coastline. Far worse is the disruption and destruction of the ocean plankton pastures in the vast 99+% of the oceans that make up the Seven Seas.
It’s not to late to restore and regenerate ocean plankton, our greatest ally. The power of the ocean to manage CO2, it’s temperature, and our entire planetary climate is far greater than commonly represented. It is not too late for us to help, by restoring ocean plant life to recent levels of health and abundance the ocean plankton can rapidly save itself and us!
This solution is remarkable in that it has come of 25 years of intensive international research by governments, academia, and citizen scientists like myself. IT JUST WORKS!
Here’s a photo (below) that speaks a thousand words. In 2012 with just 10 shipmates I took a modest fishing boat out to sea in the NE Pacific. We carefully spread 100 tonnes of mineral dust on a dying ocean pasture. The cost of that blessed dust is less than $50,000 (fifty thousand dollars). The ocean pasture turned from being a blue desert into a lush green pasture. The very next year the fish came back, hundreds of millions of additional salmon.
To begin join me, lend a hand to prepare for our voyages of recovery.