Removing derelict fishing gear can increase harvest value

The project in the lower Bay waters ran for six years, from 2008 to 2014 and was led by professors Donna Bilkovic and Kirk Havens.

Andrew Scheld, author of the study and assistant professor at VIMS, said: “It is well known that derelict fishing gear can harm the environment and increase crab mortality.

“But the economic impacts of this ghost fishing have rarely been quantified. Our study shows that VIMS’ collaborative efforts to remove ghost crab pots from the lower Bay led to an additional 13,504 metric tonnes in harvest valued at $21.3m.”

This was a 27% increase on what would have occurred had the pots stayed in place.

The programme was unique in terms of its employment of commercial crabbers to find and remove derelict gear during their winder closed-fishing seasons. Crabbers often lose pots to storms, boat propellers and other causes.

Mr Havens added: “The crabbers removed 34,408 derelict crab pots during the programme’s six year run. At the same time, harvests and gear efficiency were observed to increase dramatically.”

The scientists conducted the study by modelling and comparing crab harvests with and without the removal of derelict pots in 54 fishery-management areas in lower Chesapeake Bay.

Researchers converted the calculated harvest numbers to monetary values using the average annual dock price for hard-shell crabs in 2014 dollars.

“We estimate that crabbers harvested about 60 million more crabs due to the ghost-pot removals,” said Ms Bilkovic.

She concluded: “That’s one extra blue crab each time a pot is retrieved - crabs that would have otherwise been captured or attracted to the now absent derelict gear.”

This programme to remove derelict crab pots was paid for through disaster-relief funds made available in 2008 when the US Department of Commerce declared the Bay’s blue crab industry a “commercial fishery failure” following many years of declining harvests.