Wildlife Health
Stellwagen Bank
A harbor seal swims in the waters of Stellwagen Bank. Credit: Elliot Hazen, NOAA Fisheries permit #14245
Why is it a concern?
For “key” species in marine sanctuaries (e.g., keystone species, foundation species, indicator species, and other focal species) measures of condition and health can be important in determining the likelihood that these species will persist or recover and continue to provide vital ecosystem functions and services. Measures of health (condition) may include growth rates, fecundity, recruitment, age-specific survival, tissue contaminant levels, pathologies (disease incidence, tumors, deformities), injuries and the presence and abundance of critical symbionts or parasite loads.
The sand lance is a key species within the sanctuary and serves as the primary prey of humpback whales. Sand lance availability is largely dependent on environmental conditions and predator-prey interactions. The southern range of the copepod, an important food of the sand lance, is receding northward from Cape Cod as part of a warming trend. This copepod is considered to be an important prey species for sand lance. Additionally, the availability of sand lance is associated with the species mix and abundance or its principal larval predators, herring and mackerel. There has been a recent dramatic population increase in herring, and it is uncertain what impact this will have on sand lance populations.
Atlantic cod, Gadus morhua, is a keystone predator species of major ecological importance within the Stellwagen Bank National Marine Sanctuary. Cod populations in the Gulf of Maine have been exploited commercially for several hundred years, and continue to be heavily exploited today.
Overview of Research
| Project Name |
PI and contacts |
Links |
Distribution and relative abundance of sand lance in the SBNMS |
David Wiley |
No URL available. |
The sea scallop (Placopecten magellanicus) has over 100 blue eyes along the edge of its mantle, with which it senses light intensity. This mollusk has the ability to scoot away from potential danger by flapping the two parts of its shell, like a swimming castenet. Credit: Dann Blackwood, USGS
Science Needs and Questions
- What is the status of sand lance and herring populations in the region?
- Will the removal of non-commercially important species (bycatch) during fishing activities have any long-term impact?
Education and Outreach Material
Interview with David Wiley on humpback whales and sand lance
References
Anon. 2004. Marine Mammal Vessel Strike Action Plan. A Report to the Stellwagen Bank National Marine Sanctuary Advisory Council, October 2004.
Auster, P.J. 2002. Representation of biological diversity of the Gulf of Maine region at Stellwagen Bank National Marine Sanctuary
(Northwest Atlantic): patterns of fish diversity and assemblage composition. p. 1096-1125. Managing Protected Areas in a Changing World. S. Bondrup-Nielson, T. Herman, N.W.P. Munro, G. Nelson and J.H.M. Willison (eds.). Science and Management of Protected Areas Association, Wolfville, Nova Scotia.
Crawford, J. In Prep. An analysis of change in maximum fish length of 17 commercially important fish species. SBNMS.
Frank et al. 2005. Trophic Cascades in a Formerly Cod-Dominated Ecosystem. Science 308: 1621–1623.
Jackson et al. 2001. Historical Overfishing and the Recent Collapse of Coastal Ecosystems. Science 293: 629-637.
NOAA. 2001. U.S. Atlantic and Gulf of Mexico Marine Mammal Stock Assessments- 2001. NOAA Technical Memorandum NMFS-NE-168. U.S Department of Commerce, National Oceanic and Atmospheric Administration.
Steneck et al. 2004. Accelerating Trophic-level Dysfunction in Kelp Forest Ecosystems of the Western North Atlantic. Ecosystems 7: 323–332.
Wiley, D. N., J.C. Moller, and K.A. Zilinskas. 2003. The distribution and density of commercial fisheries and baleen whales within the Stellwagen Bank National Marine Sanctuary: July 2001-June 2002. Marine Technology Society Journal 37:1 35-53.