A Holistic Approach to Fishery Management in the Gulf of Maine
PI: Dr. Les Kaufman, Boston University *
The Gulf of Maine comprises 36,000 square miles of ocean along 7,500 miles of coastline, from Massachusetts to Nova Scotia. The Gulf’s frigid, nutrient-rich waters make it one of the most productive marine habitats in the North Atlantic, inhabited by a wealth of marine species, including 176 species of fishes, 40 species of marine birds, 17 cetaceans, 2 pinnipeds (and several others visiting from the north), and 2 endangered species of sea turtles. Yet despite this diversity and the ecological connections between them, each species has historically been managed independently from the others. This management paradigm has failed, however, as centuries of unsustainable exploitation have brought the Gulf of Maine’s marine biota over a threshold for dramatic change in ecosystem structure.
Now, a relatively new, holistic approach to fisheries management known as Ecosystem-Based Fisheries Management (EBM) has been proposed for the western part of the Gulf. This approach may be the key to managing and maintaining a healthy and sustainable relationship between the marine ecosystem and all human activities, fishing but one among them.
Funded by the Institute for Ocean Conservation Science, Dr. Les Kaufman, Professor of Marine Biology and Conservation at Boston University, has been working since 2004 on a field study of groundfishes (fishes that live in close association with the sea bottom) in the Stellwagen Bank National Marine Sanctuary (SBNMS) within the Gulf of Maine. Dr. Kaufman, his fishing industry partners, and his students have been looking at the movement patterns, food web interactions, and population structure of a number of common and commercially important fish species found in the SBNMS. This multidisciplinary investigation is intended to explore the need and provide scientific underpinnings for EBM in the region.
One goal of the project is to combine genetic analysis and acoustic tracking to determine whether or not groundfish (e.g. cod, cusk, and haddock) are year-round residents to the SBNMS or only transient visitors. Resolving between these alternatives is important because localized behavior results in greater risk to commercially targeted species, raising the possibility that fish populations can be locally “fished out. “ These studies could also reveal the amount of time needed for these fish to be replenished from their currently depleted state, based upon measured rates of migration and recruitment. Localized populations are also highly vulnerable to destruction of habitat, exhaustion of forage fishes on which the resident groundfishes depend, and any major ecosystem alteration, because they are reluctant to just move off to another area. Considering the unsustainable past management of marine habitats in the Gulf, ecosystem change is a real and serious threat.
Another objective of the project is to look at the intricate interactions between species, in terms of predator-prey relationships. Dr. Kaufman is especially interested in determining if there are any keystone species in SBNMS — that is, species that are particularly important because they have a profound effect on their environment relative to their abundance.
The project also aims to determine which demographic segments of groundfish populations are most crucial to population recovery and learn how best to protect these individuals. Findings to date suggest, for example, that large, mature female cod (10+ years old) are a critical management target. Studies of their movements and habitat use patterns are underway to determine where and when management efforts should be focused.
Only in recent years have biologists come to agree that species-based management of marine ecosystems is too fragmented, and that management plans cannot have long-term effectiveness without incorporating the entire ecosystem, the interactions between ecosystems, and the cumulative impact of humans. By monitoring ecological processes (e.g. food webs, habitat quality, the determinants of species diversity) that operate both inside and outside the SBNMS, recognizing the importance of genetic, species, and habitat diversity, and also accommodating and promoting sustainable human practices within the Sanctuary, the integrity of the SBNMS can be maintained. Dr. Kaufman’s research aims to reveal many of the complex interactions between marine organisms and their environment in the Gulf of Maine, to support the development of EBM in the region.
Read Bostonia magazine article about Dr. Kaufman’s work in Stellwagen Bank , Gulf of Maine
Dr. Les Kaufman’s bio