Sharks have been in existence for nearly 400 million years, making them one of the oldest vertebrate groups on the planet. But in just the last 15 years, scientists have noted that at least eight species of sharks have declined 50 percent.
There are a host of reasons to explain their rapid disappearance: environmental pressures, unstable ecosystems, and even fishing itself. When commercial vessels operate on the high seas, some will unintentionally catch non-target fish and wildlife, such as Blue Sharks -- a fishing method known as "bycatch." According to a new report published by the international advocacy organization Oceana, Blue Sharks are particularly vulnerable to bycatch because they swim in temperate and tropical open waters that cross national lines.
"It's critical to understand the impact of commercial fishing on wildlife."
In order to better understand the risks facing Blue Sharks, Oceana devised an innovative technological approach to compare the movements of the sharks with those of the vessels. Researchers used data collected from tagging 10 Blue Sharks off the East Coast and then overlapped that with publicly available information known as AIS, or automatic identification system. AIS, according to analyst Lacey Malarky, is data transmitted by vessels. She explained it was originally intended so that vessels could avoid collisions by providing information on the whereabouts of other vessels as well as how fast they're going. Oceana used that information and shared it on a public interface called "Global Fishing Watch," so that any member of the public, including researchers and scientists, can track and view commercial fishing activity.
"Global Fishing Watch utilizes [AIS] and it provides a global feed of vessel locations all around the world this data. It's kind of like a GPS signal. So Global Fishing Watch uses this data and uses big data analytics, cloud computing and machine learning to then identify where vessels are actually fishing rather than when they're transiting from one location to another."
Oceana then compared that data set with the information collected from satellite tagging the 10 Blue Sharks. As outlined in a report released Thursday, Oceana found that two Blue Sharks on four separate occasions came very close to three different fishing vessels throughout the 110-day tracking period.
So why does this data matter?
According to Malarky, this information will be useful to help inform scientists, researchers and fisheries make critical decisions relating to bycatch protocol, including, identifying hotpots and creating time area closures so that fishing is restricted in areas where vulnerable species are present.
These decisions could decide the future of Blue Sharks, which, Oceana says, dominate shark bycatch in longline fisheries. The near-threatened species make up between 50 and 90 percent of shark bycatch in many places around the world.
The Blue Shark case study is just the first step in understanding the impact of commercial fishing on marine life, Malarky added, saying more research will be needed to expand the case study to include other vulnerable organisms.
"We used this case study with Blue Sharks but we hope to work with shark researchers in the future to add additional data, additional shark species and other marine life as well into the Global Fishing Watch work-space," she said.
Discover other ways how technology and the environment work together:
Plastic is toxic to the world's oceans, but corals find it tasty
The RoboBees from 'Black Mirror' exist, but don't worry, they aren't killing anybody
This wearable device filters polluted air and lets you 'breathe your own forest'