“Sharks have persisted for at least 400 million years and are one of the oldest vertebrate groups on the planet. However, these predators are experiencing population decline significant enough to cause global concern,” lead author Boris Worm, professor of biology at Dalhousie, stated.
“Global Catches, Exploitation Rates and Rebuilding Options for Sharks,” is a paper published recently to calculate the total shark mortality and to outline possible solutions to protect the world’s shark population. “Global Catches, Exploitation Rates and Rebuilding Options for Sharks,”is made up by Boris Worm and three other researchers from Dalhousie University. They teamed up with scientists from the University of Windsor in Canada and scientists from Stony Brook University in New York as well as scientists from Florida International University in Miami and University of Miami.
“This is a big concern because the loss of sharks can affect the wider ecosystem,” said Mike Heithaus, executive director of FIU’s School of Environment, Arts and Society. “In working with tiger sharks, we’ve seen that if we don’t have enough of these predators around, it causes cascading changes in the ecosystem, that trickle all the way down to marine plants. Such changes can harm other species, and may negatively affect commercial fisheries,” Heithaus explains as co-author of the paper.
Data collected and recorded for the updated study showed that the death of sharks were estimated at 100 million in the year 2000 and 97 million in the next year (2010). The total possible statistics of mortality is between 63 to 273 million every year.
The major root in the significant population decline is combined by the global boom of shark fishing, primarily for their fins, and the relatively decreased pace in the growth and reproduction of the sharks. Since the data of shark catches is inadequate in most parts. If the world, the wide range of possible mortality is based on available data of shark deaths and the calculated projections for unreported, discarded and illegal catches. Even in the uncertainty, there is small question that sharks are being caught faster than they can reproduce and multiply.
“Sharks are similar to whales, and humans, in that they mature late in life and have few offsprings. As such, they cannot sustain much additional mortality. Our analysis shows that about one in 15 sharks gets killed by fisheries every year. With an increasing demand for their fins, sharks are more vulnerable today than ever before,” Worm stated.
While some sharks have been receiving protection through national and international agreements, the team of researchers suggests legislation should be more expansive to a larger number of species. Imposing a tax on the export and import of shark fins could also help slow down the demand and generate income for domestic shark fisheries management, according to Boris Worm.
“The findings are alarming, but there is hope. Existing regulations are a great start but we must ensure they are adequately enforced. In addition, more nations must invest in sustainable shark fisheries management. This means introducing catch limits, trade regulation and other protective measures for the most vulnerable species and those that move across international boundaries.” said Samuel Gruber from the University of Miami.
The main message the research is offering is sustainability. The role of sharks is widely essential to sustain a balanced marine ecosystem. Boris Worm and his team of researchers insist that protective measures must be heightened significantly to prevent further depletion in the future that may lead to possible extinction of one of the world’s top predators.