Everybody wants to save the whales, turtles and dolphins. And that´s fine. In conservation it is helpful to rally around around a “charismatic” species, such WWF´s famous panda. Cuddly creatures make powerful symbols which most of us can identify with at an emotional level. We need not know anything about elephant physiology or ecology to love elephants. And we don´t need to understand the complex social and economic forces threatening orangutans in order to realize they are worth protecting.
But these charismatic species only tell a part of the story. There are creatures which are not as cute, which are misunderstood and even hated, which are incredibly important to our collective wellbeing. And it is important we know their story and correct these misunderstandings.
And that is why I was pleased to see a YouTube video going around about how wolves have a very positive influence on their environment. While wolves are formidable creatures, they still inspire fear, and therefor do not benefit from the widespread goodwill which koala bears enjoy. And I hope this video will help us all appreciate wolves more than we do. In case you haven´t seen it, it spells out how introducing even a few wolves can set off a chain reaction through the ecosystem that results in cleaner, deeper rivers, which are less prone to flooding and cause less erosion.
Because I live on the Mexican Caribbean, this got me thinking about sharks. Sharks are the opposite of a charismatic species. They are vilified unlike any other creatures on Earth. On average, sharks kill about 5 people a year. In return we kill well over 100 million sharks each year. And yet these supposed “monsters” are incredibly important to the health of marine ecosystems, particularly to that of coral reefs.
The reason is that sharks feed on fish which feed on creatures which feed on algae. For example, less sharks, means more rays, which means less shellfish, which results in more algae. Because algae grows faster than just about anything else, it is crucial that it be kept in check by grazers. In the absence of these grazers, it can quickly grow out of control, overwhelming all other species and suffocating the entire ecosystem.
And it is really about these grazers that I want to talk about. Sharks, as misunderstood as they are, do have their fan club. Though I doubt they´ll ever be as popular as dolphins, there is at least a growing awareness that we treat them unfairly. Although I´m glad that scary predators are getting some positive attention, I´d like to talk about the bottom-feeders nobody thinks twice about. And as far as I know, nobody gives a damn about sea urchins.
And yet sea urchins have proven themselves to be key species in two completely different marine ecosystems: Alaskan Kelp Forests and Caribbean Coral Reefs.
In Alaska, overfishing led to a decline in seal populations simply because there was no longer enough fish to sustain them. Faced with this scarcity, Killer whales which normally hunt seals started hunting more sea otters. Sea otters in turn feed on urchins that eat algae. In the absence of otters, the urchin population (from the genus Strongylocentrotus) exploded, and overgrazing lead to the collapse of kelp forests.
In the Caribbean however, it was the loss of urchins which led to disaster. In 1983 an epidemic (or rather, epizootic) killed upwards of 97% of the Diadema sea urchins (Diadema antillarum) in the Caribbean, and the results were catastrophic. Coral reefs were overgrown with algae, and entire ecosystems collapsed, and to this day have not recovered. Though there are many reasons (pollution, climate change, etc.) why live coral coverage in the Caribbean is currently calculated to average only 8% the die-off of this lowly sea urchin 30 years ago was the turning point. In fact, studies suggest that reef recovery is aided significantly by re-introducing this species. It has also been suggested that prior to the epidemic the population density of this urchin was uncharacteristically high, due to overfishing of its predators. So we eliminated the sea urchin predators, leading to sea urchin overcrowding, which resulted in a deadly epidemic which culminated in ecosystem collapse throughout the Caribbean.
In this case urchins play the slain hero, in the previous story they were the opportunistic villain. And in neither case did mankind set out to cause harm. Both instances took us by surprise. We could not have anticipated the profound impact of our actions, because we´re not as smart as we like to think we are. If we were, we would realize that we are all connected in ways we cannot possibly imagine, and behave accordingly. More cautiously. More humbly.
And so while whales and turtles and dolphins are universally adored without need for reason, reason is beginning to show us that wolves and sharks are not as evil as we once thought. And that species such as sea urchins, which fail to capture our imagination at all, can be the most important of all.
So it´s no longer enough to care for the good. Or the bad. We also need to start loving the ugly.
David Nuñez is a biologist, photographer and author of several books on the Wildlife of the Mexican Caribbean, as well as a founding member of Mexiconservación.