A sustainable harvest?

Photo by Tertia Cote.
Too much of a good thing?

I sat down to a feast of fresh Maine lobster on Wednesday, my second this summer, and, to be honest, I completely enjoyed it from start to finish, despite the complete mess I made on both table and clothing (I should probably have a bib at home for this…)- but I had to wonder, given the cycles of boom and bust in the history of New England fisheries, why dining on lobster is so easy on my wallet these days and whether that would continue in the future.  So I did a little reading on the state of specific groundfish and shellfish today, how fishing communities have responded to management plans and concerns, and what scientists think about the future. (There is no way that I read every article and study that is out there, and I’m sure some big ones got away, but I think I’ve done a reasonable job of putting together an overview.)

As I mentioned in my last post, fishery management along the New England coast became more direct starting in the mid 1990s. In addition to reducing the number of fishing days at sea and requiring catch reports, specific areas within Georges Bank were permanently closed to fishing activity (there had been seasonal closures before)- there was particular concern over the decline of cod, haddock, and flounder stocks. Individual fishing communities also acted independently to address some of the issues they saw, so that fishing could remain a viable way of life. The Cape Cod Commercial Hook Fisherman Association, for example, started in 1991 with the goal of helping fishermen who use traditional gear (like hooks and gillnets) share a fishing quota. Because their methods for catching haddock have very low by-catch (meaning cod), they have been able to gain special access to closed areas for their members.

The bright spots amid a dark sea. Are these actions paying off? Well, there has been some definite progress in some areas. Georges Bank’s Closed Areas I and II have helped spawning-stock biomass of cod, haddock, and yellowtail flounder increase (Murawski et al. 2000). According to the NOAA Fisheries site, both yellowtail flounder and haddock have sustainable harvests on Georges Bank. Although not the original intention, the closed areas of Georges Bank have also contributed to the doubling of New Bedford’s scallop harvest between 1999 and 2005 (Environmental Entrepreneurs, 2005) and tempering of year-to-year fluctuations in the scallop harvest (Murawski et al. 2000). Researchers from UMASS at Dartmouth use regular video surveys, which are less intrusive than dredging, to assess scallop stocks, and they’re working to assess groundfish in the same manner (which is harder since groundfish, unlike scallops, move) (Miller 2012). Lobster stocks on Georges Bank and the Gulf of Maine have been at record levels of abundance and recruitment (Wilson et al. 2007), partly because the fish who would normally eat them are so few (hence, I can afford multiple lobster dinners this summer). And cooperative research plus a transparent managing process have helped build trust among the many groups interested in fisheries management (SRA-Touchstone Consulting Group 2011).

The goal is to keep these boats active, while maintaining healthy stocks.

But big concerns remain. NOAA feels the flounder harvest in the Gulf of Maine is unsustainable, and haddock stocks there, although abundant in the early 2000s, have declined since then. Although lobster in northern New England is plentiful, stocks in Connecticut, Rhode Island, and southern Massachusetts collapsed under the combined weight of a decline in settling young and shell disease (Wahle et al. 2009). Cod stocks, although recovering a little on Georges Bank, continue to be overfished on Georges Bank and the Gulf of Maine, and are not expected to meet the 2014 rebuilding goals. Several studies (Murawski et al. 1998, Hutchings & Reynolds 2004, Environmental Entrepreneurs 2005) expressed concern that limits tend to be raised at the first sign of recovery rather than later when harvest would be more sustainable. At the same time, members of the fishing industry felt that the management process was not concerned with advancing their interests (SRA-Touchstone Consulting Group 2011). And, although my bank account feels good when I buy lobster at the store, systems that have become something of a monoculture, like with lobster as their predators were reduced, have nothing to fall back on when trouble appears.

What does the future hold? Obviously, this is a difficult one to be sure about- at best recovery will be a slow but steady process. A 2005 assessment put cod on Georges Bank at 1/10 that of a healthy sustainable population (New England Fishery Management Council 2005), a prospect that is not encouraging in light of a review of 90 collapsed populations across a range of species (Hutchings & Reynolds 2004) which found that, 15 years after collapse, only 12% had made a full recovery and 40% had seen none at all- the rate of recovery depended in part on which species it was, but also whether fishing continued during recovery and how the habitat had been impacted by fishing activities. Why does recovery take so long for some species? Even when you target other species, species in decline may be by-catch. The young of some species also depend upon certain habitats to provide refuge from predators- if those habitats were on sea floors damaged by dredging, it can take up to 100 years for that habitat to recover (Environmental Entrepreneurs 2005).  How does this play out for cod? As I stated before, cod have not recovered in the way that flounder and haddock have on Georges Bank, and there have also been changes in the composition of the stocks. Because mesh-size allows smaller individuals to slip through and also because the population feels stress from fishing pressure, there has been a trend toward earlier maturation and smaller size at maturity (Hutchings & Reynolds 2004). There are further concerns for cod and lobsters as ocean temperatures rise. Cod are generally not seen in waters above 12° C, and recruitment declines above 8.5° C (Drinkwater 2005); if current temperatures along the New England coast increased by 1° C, stocks on Georges Bank are predicted to decline, at 3° C that decline would spread to the Gulf of Maine, and at an increase of 4° C the stocks in Georges Bank are predicted to disappear. As of 2007, shell disease had not been seen in lobster populations above the southern Gulf of Maine (Wahle et al. 2009), but that could change with warmer water temperatures.

So, this seems like a pretty dark forecast in some respects. As someone who really enjoys seafood and plans to munch on fish and chips at the NH Highland Games this weekend, I have an interest in healthy, sustainable marine harvests. I also want to see protected marine ecosystems and productive fishing communities along our coast- all of that seems like a tall order, but I imagine that there are a variety of ways in which all of us can work toward those goals. In my next post, I’ll look into what we can do to promote fish and fishermen.

Works Cited:

Drinkwater, K.F. 2005. The response of Atlantic cod (Gadus morhua) to future climate change. Journal of Marine Science 62: 1327-1337.

Environmental Entrepreneurs. 2005. Restoring fisheries: a New England perspective. New York: 1-7.

Hutchings, J.A. and J.D. Reynolds. 2004. Marine fish population collapses: consequences for recovery and extinction risk. BioScience 54(4): 297-309.

Miller, N. 2012. Something’s fishy, part II: educators partner with fishermen to measure stocks on Georges Bank. SOCO August 2012: 26-30.

Murawski, S.A., Brown, R.W., Cadrin, S.X., Mayo, R.K., O’Brien, L., Overholtz, W.J., and K.A. Sosebee. 1998. New England groundfish. In: Our Living Oceans: Report on the Status of U.S. Living Marine Resources, 1998. National Marine Fisheries Service, on-line version: Feature Article 2, http://spo.nwr.noaa.gov/fa2.pdf

Murawski, S.A., Brown, R., Lai, H.-L., Rago, P.J., and L. Hendrickson. 2000. Large-scale closed areas as a fishery-management tool in temperate marine systems: the Georges Bank experience. Bulletin of Marine Science 66(3): 775-798.

New England Fishery Management Council, Groundfish Science & Stock Status, 15 Sep 2005. http://nefsc.noaa.gov/groundfish/science/reports/GroundfishAssessmentReviewMeetingII.pdf

SRA-Touchstone Consulting Group. 2011. A Review of the New England Fishery Management Process. 1-19.

Wahle, R.A., Gibson, M., and M. Fogarty. 2009. Distinguishing disease impacts from larval supply effects in a lobster fishery collapse. Marine Ecology Progress Series 376: 185-192.

Wilson, J., Yan, L., and C. Wilson. 2007. The precursors of governance in the Maine lobster fishery. PNAS 104(39): 15212-15217.