ecosystem importance: death of a kelp system (Introduction)

by David Turell , Friday, July 22, 2022, 22:52 (636 days ago) @ David Turell

A great example of ecosystem importance:

https://oceanbites.org/the-death-of-an-ecosystem-understanding-the-collapse-of-northern...

"Wild kelp forests thrive in Monterey Bay, but two hundred miles north of Monterey, off the coast of Sonoma and Mendocino counties, the ecosystem collapsed in 2014. The shallow waters rapidly transformed from a lush, vibrant forest into a desolate swath of urchin barrens, an ecosystem marked by masses of sea urchins and little else. Kelp die-off is normal in small patches, but the drastic decline in kelp forests that year occurred along hundreds of miles of continuous coastline.

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"Kelp forests rely on the upwelling of cold, nutrient-rich seawater to maintain the ecosystem’s species richness and complexity. The persistence of warm, nutrient-poor waters after 2014 could have been one factor that contributed to the dwindling of kelp forests. But the scientists knew—from the satellite data—that kelp forests had survived a warming period in the 1990s, so they guessed that warming could not be the only circumstance leading to the kelp’s demise.

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"The structure of kelp forests provides varied habitats that are ideal for a diverse set of animals. Abalones, snails, and sea urchins feed on the kelp’s leaves, while fish, sharks, and sea otters take shelter and hunt within the dense stems.

"Sea otters and sunflower stars prey on sea urchins, which are voracious consumers of kelp. Having been wiped out by settlers in the 1800s, sea otters no longer grace the waters off northern California and thus do not threaten the region’s urchins. Though the loss of sea otters decreased the resiliency of kelp forests, sunflower stars were enough to keep the sea urchin population in check. In 2013, however, a disease called sea star wasting syndrome appeared along the Pacific coast. The malady turned sea stars to mush, and anyone walking the rocky beaches that year could find the stars on shore, slimy and dismembered. The disease ravaged sunflower star populations. With neither sea otters nor sunflower stars to hunt them, sea urchins took over the coastline and devoured the remaining kelp.

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"Will kelp forests recover now that ocean temperatures are cooling off? Scientists are doubtful. The local extinction of sunflower stars may have degraded the ecosystem’s resiliency beyond repair. Studies have shown that urchin barrens are a stable ecosystem—one that is not altered by slight changes to the system. Small decreases in the urchin population (or small increases in kelp growth) will not be enough to reverse the ecosystem back to kelp forests."

Comment: ecosystems are vital for the health of the living planet. That is a designing God saw to it th at a very diverse bush of life was developed as evolution progressed to humans. Looking back there were ecosystems satisfying the need for food from the beginning of evolution through all ensuing stages. dhw denigrates this as God providing 'humans (plus food)', as if that was all that was necessary for God to do. The obvious history tells us the logical otherwise.