Protecting Ocean Ecosystems
Atlantic Herring at the Center of a Ripple Effect
It is often the little things that matter most. Such is the case with Atlantic herring. As a keystone forage fish species in New England waters, Atlantic herring play a critical role in the marine food web by feeding on zooplankton, krill, and fish larvae and serving as a primary food source for numerous larger fish species, including cod, haddock, and bluefin tuna, as well as whales, seals, dolphins, and birds. As such, numerous stakeholders across various commercial and recreational fisheries, along with ecotourism and sport fishing operators, resource managers, and conservationists, maintain a shared investment in the health of the Atlantic herring population.
As expressed in the recent Associated Press article, Big Herring Catch off New England Comes with Worries, stakeholders regard Atlantic herring as a linchpin of the marine environment, with steady populations required to ensure the stability of many fisheries and industries. Given the extensive ecological and economic interdependencies surrounding Atlantic herring, the resource must be managed with an eye towards its vital functions and interactions throughout the marine ecosystem.
Forage fish occupy a significant, yet fragile, space in marine ecosystems. These fish populations face threats of localized depletion based on intensified regional harvest pressures, which can ultimately result in sweeping impacts to predatory species reliant on local food abundances. Furthermore, due to their propensity to move in large schools even with depleted stocks, forage fish remain easily catchable at low abundance levels, which renders them particularly vulnerable to overfishing. Forage fish may also have lower potential to rebound if overfishing or environmental factors result in spawning stock declines below a critical threshold.
Based on their integral role in the marine environment, Atlantic herring cannot be managed in a silo under a traditional fisheries management strategy that focuses solely on one fish species in isolation. To effectively assess the health of this forage fish species and determine the best approaches for managing it, the entire ecosystem must be taken into account.
Ecosystem-based fisheries management employs integrated approaches to study and manage the resources of an ecosystem, including its geographically specified system of organisms, the environment, and the processes that control its dynamics. To sustain the integrity of New England’s marine environment, as well as the fisheries, industries, and communities that depend on it, management decisions for Atlantic herring must incorporate an ecosystem-based approach that accounts for the extensive predator-prey interactions involving this species, the cumulative impacts of environmental stressors affecting this population, and the array of human uses reliant upon this resource. After all, the benefits and risks to a species at the center of a widespread ripple effect become the shared strengths and weaknesses of the interconnected web within New England waters.