Full report - Conservation Gateway

Chapter 7 - Demersal Fishdependent (NMFS 2009c). While the degree to whichclimate change will influence these critical life stages isunclear, the topic is of growing concern in the region andbeyond.Several studies have been conducted which documentshifts in species range in response to temperature changes,while others have been undertaken to predict potential futureshifts. For example, Mountain and Murawski (1992)observed latitudinal shifts in Gulf of Maine groundfishdistributions in response to temperature changes.University of Rhode Island researchers have also observedlong-term shifts in species composition (from vertebratesto invertebrates and from benthic to pelagic species) withinNarragansett Bay and surrounding waters over the past50 years (Collie et al. 2008). Smaller warm-water specieshave increased while cool-water species have decreased;these changes were attributed to a variety of factors, includingclimate change and increasing water temperatures.Lastly, Fogarty et al. (2008) looked at potential shifts inthe range of Atlantic cod and concluded that the probabilityof catching cod decreases markedly with increasingbottom water temperatures. They also noted that reducedjuvenile Atlantic cod survival caused by increasing watertemperatures could significantly impact long-term recruitmenttrends.Energy developmentAs interest in alternative and renewable energy productiongrows in the United States, energy development in marinewater, including oil and gas exploration and extraction,wind and tidal energy facilities, and liquefied natural gas(LNG) terminals, are emerging as an important humaninteraction. Impacts from oil and gas activities includedirect habitat disturbance from exploration and developmentactivities and oil spills during production and transportation.Impacts from wind and tidal energy includedirect habitat disturbance during construction, alterationof hydrologic regimes, and noise. Impacts from LNGdevelopment include direct habitat impacts from the constructionof offloading facilities and entrainment in waterwithdrawals associated with LNG conversion from liquidto a gaseous state (Johnson et al. 2008).Potential impacts from oil and gas development aremost likely to occur on Georges Bank and along theContinental Shelf in the Mid-Atlantic because theseareas are richest in these resources, and proposals for extractionhave already been made for these areas. Severalwind farms and tidal energy facilities have been proposedwithin the region, though very few facilities have actuallybeen permitted and constructed. Two LNG terminalswere recently sited in the waters of Massachusetts Baynear Gloucester.Power plantsCoastal power plants have the potential to impact demersalfish species in a number of ways, including by increasingwater temperatures as a result of discharging coolingwater and increasing direct mortality through entrainmentand impingement in cooling water intake systems(Johnson et al. 2008). Interactions will be dependent onthe location and design of cooling intake and discharge facilities,and the degree to which individual species utilizenearshore coastal waters. The ASMFC has raised concernsabout increased water temperatures, and impingement incooling water intakes has been specifically identified as aproblem for a number of species including winter flounder,tautog, and weakfish.Nearshore habitat degradationNearshore habitat degradation is a pervasive problemthroughout much of the region, particularly in the centraland southern portions. Habitat degradation takes a numberof forms, including direct habitat loss due to coastaldevelopment and conversion, water quality degradationfrom point and non-point source pollution, dredging anddredge spoil placement, dredging for beach nourishmentprojects, and hydrological modifications resulting fromditching and channelization. The ASMFC has identifiedthese types of nearshore habitat degradation as significantthreats to many of the species they manage, includingspot, weakfish, tautog, scup, black sea bass, summer flounder,and winter flounder (ASMFC 2009).Northwest Atlantic Marine Ecoregional Assessment • Phase 1 Report 7-71