Tonight CNN reports on a renowned scientist predicting apocalyptic change to the Great Barrier Reef. The story is disheartening. But I did attend a lecture by another marine scientist from University of Maine which gave me a more nuanced view.
Humans are perpetrating a shift in world species. The analysis is clear. The question though is whether the detrimental changes on our reefs are permanent. Permanence depends on how we measure data over time horizons. Over a year? decades? Thousands of years? A more interesting question is whether we can rehabilitate coral reefs in a relatively short time horizon. To what extent are they capable of rebound? We may not be able to exact immediate change to a rise in water temperature. But we can change our appetite for what we consume from the sea.
Coral bleaching is the result of a stressed coral reef. A stressed coral reef, inhabited by peculiar animal species, evolves to a reef transformed by the next invader species: green plants and algae that suffocate the coral animals.
The UM professor who has studied coral reefs over the last twenty years has also documented how coral reefs rebound after bleaching events. Parrot fish are essential to a functioning reef — if you have ever snorkeled in a functional reef, you can hear the chomping of parrot fish as they graze algae on the reefs. This is essential pruning.
His studies around the world shows a dramatic ability of coral reef rebound after bleaching events when islands adjust fishing to ban exportation of parrot fish. My takeaway: never buy parrotfish in the supermarket.
My further takeaway: change is inevitable. Humans do own the world. And a small change in water temperature affects the life cycle. A rise in temperature changes the energy cycle and affects a living organism’s immunity as it redirects its resources to fight adverse environmental changes and the invasion of new species. The question is whether we can adjust the rate of change, and how we manage the change.
Picture the Gulf of Maine. In my grandfather’s day, we fished large cod. Over time, we decimated the predator species that kept everything in the lower food chain in check. Including lobster. By reducing the population of predator species, we allowed lobsters to flourish. The Gulf of Maine is now a single species fish farm.
Which is fine so long as the Gulf of Maine continues to be in the sweet spot of temperatures required for lobsters. A rise in temperature means lobsters move north and Maine would lose a vital piece of its economy.
But the story doesn’t stop there. As the waters warm, new species move in. We now see black cod in Maine.
Climate change is a funny thing. How important it is depends on the length of time reference. Do we act to preserve the climate and underwater habitat as it exists today? Are the changes we see inevitable given that climate changes imperceptibly each year but dramatically as measured over thousands of years? But given the zig zag of change over thousands of years, is the change we see today significant? How would we know given the paltry dollars devoted to environmental research?
Climate change is a hot button issue. At the very least, there are things humans can do to slow the rate of change for those things most vital to the globe. We should look at the impact of fossil fuels on global warming which does change the ocean’s life cycles. We should also take steps to enact global regulation to sustain our fish population. And don’t buy parrot fish in the supermarket.
Change is upon us, and human activity is increasing the rate of change. A bleached coral reef can be rehabilitated. Small steps make not take us to where we were but they can slow the pace for where we end up.