The Role Reversal: How the Fearsome Have Become Our Prey

Yao Ming, the emblematic pillar of the 2000s era Houston Rockets, brought unprecedented popularity to the NBA in China, where he established himself as a household name. His influence outside of the basketball court can still be felt there, now as an outspoken advocate for wildlife conservation. In particular, as an ambassador for WildAid, he has called for the end to shark fin consumption.

Shark fin soup is a staple at important events in China, and its consumption is often used to showcase wealth. China is the biggest market for shark fin. The demand for shark fin contributes to an estimated annual mortality of 100 million sharks, according to a 2013 study by Brian Worm of Dalhousie University. Fortunately, things may be looking up for sharks. Data summarized by WildAid indicates that educational campaigns involving celebrities like Yao Ming may have contributed to the 82% decline in shark fin sales in China between 2013 and 2014.

However, the situation is still grave for the feared, yet vulnerable animals. Other data from WildAid shows that the fourteen most fished shark species have all experienced population declines of at least 40%. The absolute devastation humans have brought to these species is perhaps best described by Dr. Demian Chapman of Nova Southeastern University in an interview with National Geographic, “We’ve absolutely annihilated the species on a global scale”.

So why should we care? Sharks are obviously predators, sitting at the top of many interconnected food webs of coral reef ecosystems. So when shark populations decrease, the populations of and interactions between every species under them are thrown off balance. As a result, the populations of species that are shark prey blossom and those of herbivorous reef species crash. Algae are able to grow unhindered, smothering coral and starving them of light and oxygen. Coral reefs support a plethora of marine species and are home to incredible biodiversity. There is potential for the complete collapse of an entire ecosystem.

If not for the sake of biodiversity and healthy ecosystems, we should at least care because these consequences will affect us too. Declining shark populations have the potential to negatively impact fisheries, tourism, and ultimately, the economies of countless countries and lives of millions of people.

Nowhere is the decline better exemplified than in the Red Sea, where according to Nicholas Dulvy of Simon Fraser University, there are twenty-nine shark species classified as “Threatened” by the IUCN. Furthermore, thirteen out of the fourteen most fished species can be found there. Combined with the lack of regulation, it’s obvious why shark fishing is common in the region.

In response to the lack of knowledge on the actual abundance and distribution of shark species in the Red Sea, Julia Spaet and colleagues at the University of Cambridge recently published their study in Biological Conservation. They gathered data over a 2-year period through a sampling program at specific sites along the Saudi Arabian(SA) Red Sea coast and Sudanese Red Sea coast. Underwater cameras provided images that were analyzed while longlines captured sharks which were qualitatively assessed. With the collected data, they estimated the relative abundance of shark species in the two regions.

The estimates for relative abundance of shark species in the SA region are significantly lower than estimates obtained from Australia and Fiji. Most relevantly, estimates for the SA region are many magnitudes lower than estimates for the unexploited Sudanese region. Spaet concludes that the low abundance of sharks in the SA region results from years of unregulated overfishing of sharks and their prey.

Despite the efforts of conservation groups, there’s still a lack of awareness about the negative effects of shark fishing. Education needs time, and we have little to spare. In the meantime, the responsibility of stopping the current decline in shark populations and the resulting impact on respective ecosystems falls on the shoulders of the governments. Countries where shark fin is sold, like China, must ban its sale while countries that govern oceans where the fishing occurs, like Saudi Arabia, must strictly enforce laws that prohibit fishing.

Undoubtedly, factors other than overfishing may have contributed to the low estimates of abundance in the SA Red Sea region. For example, abundance in the SA region may just be naturally low due to unknown environmental factors. However, the Sudanese Red Sea region, which has significantly higher estimates of abundance, shares the same habitat characteristics as the SA Red Sea region. No matter the opinion on Spaet’s conclusion, one thing is clear: we need more detailed data.

Regardless of the actions (or inactions) of governments, research can still be done to advance our knowledge of the distribution of shark populations and how their declines affect their ecosystems. So when action is ready to be undertaken, that knowledge will be there to help formulate the most effective conservation effort.

References

Dulvy, N. K., Fowler, S. L., Musick, J. A., Cavanagh, R. D., Kyne, P. M., Harrison, L. R., … & Pollock, C. M. (2014). Extinction risk and conservation of the world’s sharks and rays. Elife3, e00590. Retrieved from https://elifesciences.org/content/3/e00590

Hodges, G. (2016). These sharks used to rule the seas. Now they’re nearly gone. National Geographic. Retrieved from http://www.nationalgeographic.com/magazine/2016/08/whitetip-sharks-vanishing-ocean-species/

Spaet, J. L., Nanninga, G. B., & Berumen, M. L. (2016). Ongoing decline of shark populations in the Eastern Red Sea. Biological Conservation201, 20-28. Retrieved from http://www.sciencedirect.com/science/article/pii/S0006320716302415

WildAid. (2014). Evidence of declines in shark fin demand china. Retrieved from http://wildaid.org/sites/default/files/resources/SharkReport_Evidence%20of%20Declines%20in%20Shark%20Fin%20Demand_China.pdf

Worm, B., Davis, B., Kettemer, L., Ward-Paige, C. A., Chapman, D., Heithaus, M. R., … & Gruber, S. H. (2013). Global catches, exploitation rates, and rebuilding options for sharks. Marine Policy40, 194-204. Retrieved from http://wormlab.biology.dal.ca/publication/view/worm-etal-2013-global-catches-exploitation-rates-and-rebuilding-options-for-sharks/

 

 

Advertisements
This entry was posted in Conservation Biology Posts, Conservation Editorials 2016. Bookmark the permalink.

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s