Conserving marine habitats into the future

By Peter H. Taylor

TO GAIN A COHESIVE view of marine habitat conservation issues and potential solutions from a management and scientific perspective, the Gulf of Maine Council and The Nature Conservancy co-sponsored a workshop this fall called “Marine Habitats in the Gulf of Maine: Assessing Human Impacts and Developing Management Strategies,” at the Darling Marine Center in Walpole, Maine. The workshop participants - resource managers, agency and academic scientists, staff from non-government organizations and other experts - hailed from the five states and provinces that border the Gulf of Maine, southern New England and from as far away as Oregon.

The workshop was part of a larger effort to involve people from the public and private sectors to resolve the most important concerns about marine habitats in the Gulf of Maine, and offered a window into the current thinking of management and scientific experts. I'll highlight a few emergent themes from their discussions that caught my attention.


Show me the maps

Maps. We need maps. That's one of the biggest, neon-lit messages to come out of the workshop. Simply put, it's difficult to address marine habitat conservation issues without knowing where the habitats are and where human impacts occur. Two types of maps are needed. One would display the habitats of the Gulf of Maine, showing areas of cobble, sand, mud, rock ledge, kelp beds, eelgrass, salt marsh and so forth. For management purposes, according to workshop participants, such habitat maps also should indicate sensitivity to disturbance by human activities. The other map type would display the footprint (or wake?) of humans on the ocean and coast, indicating underwater pipelines, mining operations, fishing grounds by species and gear, aquaculture sites, popular locales for recreational boating and fishing, protected areas, and on and on. These maps would provide fundamental information for understanding and managing human impacts on the Gulf of Maine. Of course, my brief description of the two map types glosses over tremendous complexities and challenges. For starters, habitats can be categorized in infinite ways. It would be enormously time consuming and expensive to produce a universally acceptable, scientifically valid, management-relevant system of habitat categorization for the Gulf of Maine. Equally enormous effort could go into defining levels of sensitivity and types of human activities. Such categorization is a necessary evil whenever the real world is shoehorned onto maps. Then there's the data gathering to be done, not to mention the mapmaking itself. It's daunting to contemplate making these maps on the scale of the Gulf of Maine.

Perhaps that's why, for the most part, these maps don't exist yet. Wouldn't it be great if there were a Web site with interactive mapping where you could select one or more habitat types, click on a button, and see a map showing where those habitats are located in the Gulf of Maine? Or maybe you'd view the locations of docks and piers along the coast and get statistics on density of the structures in your area. Or you could superimpose the tracks of fishing vessels on a map of bottom habitats to understand where fishing effort is concentrated in the Gulf of Maine. These are the sorts of mapping capabilities that workshop participants hope for. Right now, you can find pieces of this information on the Web or in hard copies, but it's not easy to round up, especially in a user-friendly form. Now that technology is available to collect and distribute information on an unprecedented scale, it's really a matter of commitment and money to get the job done.

For a partial inventory of mapping projects in the region, visit www.gulfofmaine.org/marinehabitatworkshop2005.


Cumulative impacts

Another big message coming out of the workshop: We need better ways to document, understand and minimize cumulative impacts. For example, agencies that issue permits for construction of sea walls often approve most applications because each individual project can claim to have negligible impact on the environment. However, sea walls permanently harden the shoreline, altering the natural process of erosion and destroying habitats. Consequently sea walls along the coast undoubtedly have a cumulative impact on the environment.

The term “cumulative impacts,” which are not fully addressed through today's regulatory environment, doesn't just refer to multiple instances of the same type of human impact. It can also refer to situations in which multiple types of human impacts affect the same geographic area or the same component of the marine ecosystem. For example, people at the workshop noted that erosion of soil into coastal waters, dredging, jetties and sea walls all affect the amount and distribution of sediment carried in the water. Excessive sediment can interfere with the feeding of bottom-dwelling invertebrates, reduce the amount of light available to seaweeds and interfere with other ecosystem processes. The combined impact of soil erosion, dredging and sea wall construction on waterborne sediment in a given bay might be tremendous, but it could occur unrecognized if each human activity is considered independently.


Eye to the future

Managers face a huge challenge trying to deal with existing environmental problems within the confines of lean budgets. But it's vital to anticipate future threats to the region's marine environment and ocean-related economy, and these issues were discussed at the workshop, too. Of course, climate change and ocean warming threaten to alter the Gulf of Maine dramatically. Yet a different potential threat caught my attention at the workshop because it seems both significant from ecological and economic standpoints and possibly tractable from a management perspective. What if a new invasive species establishes itself in intertidal muddy habitats of the Gulf of Maine and begins to overrun mudflats from Cape Cod to the Bay of Fundy?

Muddy habitats along the coast are economically valuable for shellfish and worm harvesting and are ecologically crucial as feeding grounds for migratory birds and other species. Over the past century, the European green crab (Carcinus maenas) invaded the Gulf of Maine, which led to a decrease in clam harvests, but clamming is still a key economic engine. In the state of Maine alone, clam landings in 2004 were valued at more than $16 million. However, scientists at the workshop pointed out that the situation could worsen nearly overnight if - dare I say when - a new invasive species gains a toehold in the region's mudflats. It's entirely conceivable that a non-native species of animal or plant could overrun the mudflats, killing clams, worms and other natives. It has happened elsewhere and could happen in the Gulf of Maine. Obviously that scenario would be devastating for clammers, worm harvesters and everyone else whose livelihoods are connected to productive mudflats.

Preventing an invasion might be impossible, but what if a management framework existed to enable rapid detection and response, reducing the potential harm? At the workshop, one breakout group discussed this idea and sketched out a conceptual framework. Clam and worm harvesters, who spend lots of time on the mudflats, could act as the sentinels. They'd be provided with information, perhaps a waterproof sheet with photos, about invertebrate and algal species that scientists finger as potential invaders. If the harvesters spotted any of these species, or anything else out of the ordinary, they'd call a toll-free number or log onto a Web site to report their find. A rapid response team would be deployed to investigate the sighting and remove any invasive species that are present. The incentive for clam and worm harvesters to participate would be to protect their livelihood.

Whether this particular idea has enough merit to be implemented remains to be seen, but it's indicative of the cross-fertilization between the scientific and management com-munities at September's workshop. For a full account of the ideas emerging from the two-day gathering, keep an eye on www.gulfofmaine.org for the soon-to-be-released workshop proceedings - and ultimately look for development of an implementation strategy for marine habitat conservation. The Gulf of Maine's Council's Habitat Con-servation Subcommittee will shepherd along the implementation process in partnership with regional organizations.

Peter H. Taylor (Waterview Consulting) is a consultant for the Gulf of Maine Council's Science Translation Project.

© 2005 The Gulf of Maine Times