Sharp decline in population pushing sharks and rays towards extinction.
According to researchers, the global population of sharks and rays has dropped for more than 70% in the past 50 years, pushing the two species towards extinction. The main reason for the decrease in global population can be attributed to the sudden booming fishing industry which began in the early 1970’s and continues today. Currently, half of the world’s 31 oceanic shark species and the giant manta ray are listed as either endangered or critically endangered by the International Union for Conservation of Nature (IUCN).
Sadly, the situation is still worsening as expressed by Nathan Pacoureau, a researcher at Simon Fraser University. He has called for “proactive measures to prevent total collapse, this should be a wake up call for policy makers.”
A recent leading article on this topic “Half a century of global decline in oceanic sharks and rays” disclosed that there has been an overall 71% decline since 1970. According to the article, while sharks and rays can be affected by ship strikes, oil and gas drilling and, increasingly, the climate crisis, it was actually overfishing that was the primary cause for the decline. It was estimated that approximately 100 million sharks are killed by humans every year, causing a detrimental effect to species reproductive capacity.
Sharks are often targeted for their fins to make shark fin soup, with poachers cutting off their fins while the animal is still alive, and before their helpless bodies are discarded back into the ocean. Sharks also are unintentionally caught and killed by fishermen using large nets in their quest to catch other marine life.
Dr Cassandra Rigby, a biologist at James Cook University in Australia and study co-author said: -
“Ongoing declines show that we are not protecting a vital part of our ocean ecosystems from overfishing, and this will lead to continued decline in the health of our oceans until we do something about it,”
The research highlights the patchwork quality of fisheries management around the world. Steep declines in shark and ray numbers in the Atlantic Ocean began to stabilize somewhat after 2000 amid conservation measures, while the rate of loss has also slowed in the Pacific Ocean. But in the Indian Ocean, shark and ray abundance had plummeted continually since 1970, with an estimated drop of 84% in overall population in this time.
Scientists have suggested governments enforce “science-based catch limits” on a domestic and regional basis to ensure sharks continue their vital roles as ecosystem predators and protein source for poorer communities. Mariah Pfleger, marine scientist at Oceana, added that countries should also ban the sale and trade of shark fins. The ocean conservation group is pushing for the US to adopt such a ban, as Canada enacted in 2019.
Courtesy of Marco Poon.
Source: The Guardian, APNews
