The sea around us

Maine’s cold marine waters are some of the world’s most productive, providing habitats for a diverse and varied assemblage of species, including at least 1,600 different types of bottom dwelling organisms, 73 different types of commercially-harvested fish, and 26 species of whales, porpoises and seals. This high diversity of marine life is supported by a variety of marine and estuarine habitat types including salt marshes, sandy beaches, rocky substrates, sheltered coves, eel grass beds, muddy and sandy sediments, gravel beds, and macroalgae. Visit http://www.maine.gov/dep/blwq/doccoast/coastal3.htm for a comprehensive description of Maine’s marine habitats.

According to the Department of Marine Resources, Maine’s seafood industry provides 26,000 direct and indirect jobs and $777 million in economic impact to the state economy. Maine is also first in revenues for landed fish in the Northeast with a total landed value of all species in 2000 of $336.1 million. Atlantic herring, lobsters, the groundfish complex, and sea urchins are the largest catches by weight with lobsters, sea urchins, groundfish, soft-shell clams, and scallops comprising the highest landed value. Visit http://www.maine.gov/dmr for additional species information, current landings data, and information about state sponsored ecological studies.

Maine’s marine and estuarine waters are also used for a variety of other economic and recreational purposes including: recreational fishing; oil and cargo transportation; passenger transportation; and recreational boating. Indeed, the economic well-being of many of Maine’s coastal communities depends on the long term viability of our marine resources with many of our citizens deriving their income directly and indirectly from the ocean.

One of the challenges to managing and protecting the habitats of important flora and fauna is limited knowledge about the complex and dynamic nature of marine ecosystems. The habitat requirements of any given species can change dramatically over the course of its life. For example, the early life stages of the lobster are planktonic, subject to ocean currents and other environmental factors. Juvenile and mature lobsters are bottom-dwellers. Yet, there is much that we do not know about the life process of the lobster and other marine organisms and how susceptible they are to varying coastal conditions. Several recent initiatives are providing a foundation to determine the distribution of organisms along the coast and how that information could inform management decisions.

Marine Habitat Mapping

Increasing concern over the status of fish habitat has prompted efforts to identify areas of critical importance to depleted species. At the same time, ecologists are attempting to improve their understanding of habitat requirements for other members of the marine community and to break new ground with new management programs based on ecosystems, vs. traditional single species management approaches. Only by answering fundamental habitat questions can we begin to understand how vulnerable or resilient the marine community is to human activities. Studies of several bays in Maine in recent years present an excellent opportunity to look at marine habitat protection in nearshore ecosystems.

To date, relatively little effort had been made to document the habitat relationships of early-life stage fishes in Maine’s nearshore environments. In a step to support better ecosystem management approaches, the Maine Coastal Program provided the Maine Department of Marine Resources with funds to develop a method to identify associations between juvenile fishes and the habitat they use. The study integrated the use of traditional (e.g. fish sampling through trawl surveys) and more technologically advanced research tools (e.g. acoustic seabed classification systems, and geographic information systems.) The study generated new information about Maine’s nearshore habitats in Penobscot Bay, Saco Bay and in the Sheepscot River and allowed DMR to refine and improve its use of new technology.