Preliminary Field Research: Shark Fisheries of Peru
October 01, 2009
by Martín Benavides
Benavides is a master's student, working in the lab of Dr. Demian Chapman, Institute for Ocean Conservation Science at Stony Brook University
Sharks have captured my curiosity since childhood so it came as a bit of a surprise to me that they were not only present, but being harvested in commercial quantities off the coast of Peru, the country in which I was born. Because sharks are not often seen along the coastline and the commercial fisheries operate at an immense distance offshore, many Peruvians assume there are no sharks in Perú or that they only appear as part of the El Niño phenomenon. I had heard this when I was living in Perú as a child. But as I began to research sharks, I found evidence of a burgeoning fishery that currently remains largely unmonitored and unmanaged. With the aim of shedding light on this fishery, I applied for a grant from the Tinker Foundation and was funded to do a month-long investigation in Perú.
In preparation for my study I made contact with an organization called Prodelphinus. They are a non-profit NGO working to educate and inspire fishermen and government officials to work together to conserve marine organisms in danger of extinction. The group’s efforts to raise public awareness is coupled with careful observations and data collection gathered in the field to monitor these organisms. Prodelphinus proved to be an excellent resource because they had initiated a shark campaign and interviewed fishermen who targeted sharks along the coast. Upon arrival in Lima, Peru’s capitol, they gave me an idea of where to travel and even arranged for some of their staff to accompany me to ports for closer collaboration.
I traveled both north and south of Lima in an attempt to cover as much of the coastline as possible. At each port I interviewed any fishermen or government officials present. If allowed, I sampled the catch of any vessels that were landing sharks by taking a small, harmless fin clip from the shark. This would be used for DNA barcoding back at the lab, at the Institute for Ocean Conservation Science in New York, in order to determine which species were present in the catch. In total, I obtained over 150 shark fin samples from four ports.
Based on morphological identification alone I was able to discern five species that were present in the fishery. Blue sharks (Prionace glauca) and shortfin mako sharks (Isurus oxyrinchus) dominated longline operations, and a few porbeagle sharks (Lamna nasus) were present as well. The few gillnet samples I obtained showed the occurrence of smooth hammerhead sharks (Sphyrna zygaena), thresher sharks (Alopias vulpinus) and one prickly shark (Echinorhinus cookei). Interviews with fishermen indicated that requiem sharks (Carcharhinus spp.) are also caught in gillnets.
Future research and conservation efforts must focus on reaching the fishermen and regulators to ensure enforcement of size restrictions already in place. We need to inspire those who extract these creatures as resources to also conserve them for future generations.