By: Donna Marie Bilkovic, Guest blogger
Humans have been fishing the world’s estuaries and oceans for thousands of years. While techniques have changed over time, the availability of synthetic materials, such as plastics, has dramatically improved the efficiency, durability, and lifespan of our fishing gear. An unfortunate byproduct of these improvements, along with intensified fishing, has been an increase in the quantity and persistence of derelict fishing gear in our waters.
Derelict fishing gear possesses a long-list of unsavory traits and can last for multiple years. They damage habitat, trap and kill numerous animals including threatened, endangered, and economically important species, and pose safety hazards.
The Chesapeake Bay supports several important finfish and shellfish fisheries that use a wide array of fishing gear including crab pots, eel pots, oyster hand tongs, gill nets, fyke nets, and purse seines. Of these, blue crab pots are by far the most abundant form of derelict fishing gear found in Virginia waters of the Chesapeake Bay. There are close to 800,000 commercial crab pots licensed in the Bay and about 20 percent are estimated to be lost every year. Commercial fishers removed about 32,000 lost and abandoned blue crab pots from 3,300 km2 of Virginia’s Bay bottom over four consecutive winters through the Blue Crab Fishery Resource Disaster Relief Plan, a program funded through NOAA in response to the declaration of a commercial blue crab fishery failure in Chesapeake Bay in 2008. In those pots, 40 species of invertebrates, fish, birds, and mammals and over 31,000 animals were captured. Because pots were recovered during the cold winter months, when most animals are less active or may not be present, we suspect that the total number of species and animals captured in lost pots to be much higher.
The target species, blue crab, experiences the highest mortality from lost pots. We estimated 900,000 blue crabs are killed each year in derelict pots in Virginia, which could mean a $300,000 potential annual economic loss to the fishery. Blue crabs are not alone, important fishery species also captured and killed were Atlantic croaker, black sea bass, American eel, white perch, and catfish.
It is not all bad news. While the derelict pots were widely distributed in the Bay, there were notable hotspot areas with high density clusters of pots. These areas can be targeted for derelict gear removal and enforcement of existing regulations that require the removal of all gear during the closed fishing season in winter months. Other solutions include better educating vessel operators on derelict gear impacts and gear avoidance techniques and the application of innovative biodegradable escape mechanisms to disarm lost gear and prevent needless mortality. For more information, see our new article in Marine Pollution Bulletin: Derelict fishing gear in Chesapeake Bay, Virginia: Spatial patterns and implications for marine fauna. You can also visit the Virginia Institute of Marine Science’s website.
Donna Marie Bilkovic is a Research Assistant Professor at Virginia Institute of Marine Science’s Center for Coastal Resources Management.