The Underwater Climate Change Hero

As the saying goes, an eye for an eye, a tooth for a tooth. Following the scare from the massive destruction of the Great Barrier Reef in Australia, nature strikes again across the Pacific Ocean to the west coast of America.

Once heavily populated on the seabeds of Alaska to Mexico, only 9% of the sunflower sea star population was left to live shortly within the 5 years of 2013 to 2017. The ‘wipe out’ of 5.75 billion starfish was a result of rising ocean temperature. It has resulted from the average increase of global sea surface temperature by 0.13% over the past hundred years.

All creatures exist for a reason. All play a vital role in maintaining a healthy ecosystem. The significant loss of sea stars led to two collateral problems: an accelerating pressure on the kelp forests and the sea urchin boom.

To simplify terms, the relationship can be exemplified by the food chain between the three creatures

In the absence of sea stars, a key predator of sea urchin, there is an unrestricted growth of the sea urchin population, leading to the demise of kelp forests. Since kelp is an effective carbon sequester, the mass consumption of kelp by sea urchins led to a great cut in carbon absorption. That contributed to the growing climate crisis stemming from the high carbon levels in the atmosphere. Linking to the problem raised by scientists from the National Ocean and Atmospheric Administration, that carbon dioxide and methane levels in 2020 have reached a record high in at least 3.6 million years. The earth is more than 2 degrees Celsius warmer than it was before the Industrial Revolution in the 18th to 19th centuries.

The University of Washington collaborated with the Nature Conservancy, a US-based environmental organisation, to tackle the ongoing issues. So far, the scientists have lab-tested the growth of sea stars from newly born larvae, to mini juveniles, and even fully grown adults, in different water temperatures. This allows for the observation of the growth of sea stars in warmer temperatures to determine the success rate of reintroduction in real waters.

Just recently, in May 2021, scientists have announced that the young sea stars bear a higher heat tolerance than expected. Their resilience signals a positive outlook on repopulating sea stars in the warming waters, as scientists foresee the continuous increase in atmospheric temperature.

Furthermore, the University of Washington has established a campaign, ‘Stars for the Sea’, to raise USD 20,000 to fund the Friday Harbour Laboratories in carrying out the captive rearing program. The goal is to breed 1000 juvenile sea stars by the end of 2022 to re-introduce sea stars into the ocean and to minimize the climate threats of kelp deforestation. Ideally, hoping to restore the health of the ecosystem.

Change comes from the choices we make. If we could start reflecting on our daily habits by switching to carbon-free alternatives, perhaps we could reduce the number of ‘endangered’ labels endorsed to our sea creatures shortly.

We look forward to seeing the first batch of repopulation into the ocean to revive the dying kelp population.

By Ottilie Cheung