December 11, 2015 — The following is a commentary by Peter Himchak, Senior Fisheries Scientist for Omega Protein, a member of the Menhaden Fisheries Coalition. Mr. Himchak served for 39 years as a fisheries biologist for the New Jersey Division of Fish and Wildlife, and served on advisory and management boards for both the Atlantic States Marine Fisheries Commission (ASMFC) and the Mid-Atlantic Fishery Management Council (MAFMC). He served on the ASMFC’s Atlantic Menhaden Technical Committee and Stock Assessment Sub-Committee from 1988 until 2006:
A recent Virginian-Pilot op-ed by Chesapeake Bay Defense Foundation (CBDF) Director of Public Affairs William Tabor (“A tragedy of the Chesapeake,” 11/29) contains a deeply flawed and scientifically inaccurate take on the menhaden fishery in the Chesapeake Bay. These inaccuracies illustrate that this recently-formed organization may not have a great understanding of the menhaden fishery or basic fisheries biology. The menhaden fishery, rather than being an example of “market aggression” and “licensed plunder,” as CBDF states, is, according to all available evidence, both responsibly regulated environmentally sustainable.
Many of CBDF’s claims about the local impact of the menhaden fishery are simply not supported by the best and most current science on menhaden. CBDF advocates for banning purse seine fishing for menhaden in Virginia state waters largely over fears of localized depletion—that the menhaden fishery is taking too many menhaden from the Chesapeake Bay. But there is currently no scientific evidence that localized depletion is occurring.
Menhaden are a highly migratory species that travel to inshore and near-shore waters up and down the Atlantic coast. Nowhere has an incidence of localized depletion ever been recorded or confirmed, and many believe that the phenomenon may not even exist. The Atlantic States Marine Fisheries Commission (ASMFC), acting out of an abundance of caution and not a scientific mandate, has already imposed a cap on how much menhaden can be harvested from the Chesapeake Bay.
Fears that that the menhaden fishery is not leaving enough food for predator species is similarly overblown. Species like striped bass and bluefish generally target younger menhaden, age 1 and under. This is a segment of the menhaden population that is not directly targeted by the fishery, which mostly harvests menhaden age 2 and older. Based on stock assessment reports and the Beaufort Assessment Model, from 2004-2013, the menhaden fishery only harvested around 3.35% of the total menhaden population. The overwhelming majority of the remaining population is consumed by predator species coastwide, and the fishery does not represent a significant threat to the coastal supply of forage.
Menhaden also do not, as CBDF claims, contribute significantly to removing the “excess algae and nutrients that clog the Bay.” As several scientific papers have confirmed, menhaden are opportunistic feeders, consuming both the phytoplankton that leads to algal blooms as well as zooplankton. However, phytoplankton is consumed primarily by younger menhaden, which are not targeted by the fishery, and represent only a small fraction of the overall harvest.
The environmental impacts of the menhaden boats and purse seine nets themselves are also greatly overstated by the op-ed. CBDF cites fears of bycatch and damage to the environment as more reasons Virginia should ban purse seining in its waters. But, because they target densely packed schools of menhaden, purse seine nets are some of the most efficient methods of harvesting fish, and bycatch from these efforts are minimal. The ASMFC acknowledged in its 2010 assessment that “it is suspected that bycatch and discards of menhaden are trivial compared to total landings.”
Purse seine nets also do not frequently interact with the seafloor, and are not a significant threat to the Bay’s corals, grass beds, or oysters. And while the op-ed is concerned with the effect of water discharge from menhaden boats, any effects from this discharge are localized, and temporary. These boats also operate with the approval of relevant regulators. Compared to the widespread and long-lasting dead zones that regularly afflict the Bay, water discharge from a handful of menhaden vessels does not represent a significant, long-term environmental threat.
The menhaden fishery is already managed according to the best available science and management practices. Virginia’s quota is set in accordance with maintaining the sustainability of the stock, and fisheries science confirms that the Chesapeake-based menhaden fleet does not have a serious negative impact on the health of either the Bay or the local menhaden population. A ban on purse seining in Virginia state waters would be both unnecessary and ineffective.