3,317 and counting (the number of marine species in the Gulf of Maine)
The diversity of marine life in the Gulf of Maine region is much greater than previously thought
The Gulf of Maine Program of the Census of Marine Life, with the Huntsman Marine Science Center of St. Andrews, New Brunswick, announced today the first count of known marine species in the Gulf of Maine region -- more than 50% larger than previous estimates. The count is 3,317 species and includes both year-round species and those that migrate to the region seasonally. The Canadian-US project is part of the international Census of Marine Life. The count comes from the new Gulf of Maine Register of Marine Species, the first register of its kind for the region. According to Evan Richert, project director for the Gulf of Maine Census, "The register serves as a baseline for understanding the biodiversity of this renowned and heavily exploited region of the Atlantic Ocean."
Among the species are 652 kinds of fish, 184 species of birds, and 32 species of mammals. Microscopic plants, including the algaes, alone account for an impressive 733 different species, or more than one of every five species in the Gulf of Maine region.
"This register is the first, essential step toward understanding the Gulf of Maine as a whole ecosystem," said Lewis Incze, chief scientist of the Gulf of Maine Census, which is based at the University of Southern Maine. "This lays the foundation for the next step, which is to understand how these species interact with each other and their surroundings to make the ecosystem work."
The searchable register for the Gulf of Maine and neighboring deep sea waters was prepared by the Huntsman Marine Science Centre as part of a larger register covering the northwest Atlantic, from the Arctic to Cape Hatteras (North Carolina). The scope of life forms ranges from microscopic plants to marine mammals in waters from the lower intertidal to the deep sea. Researchers at the Huntsman, led by curators Lou Van Guelpen and Gerhard Pohle, mined literature dating back 100 years for species records and assured that the list is presented using standard species classifications. Though still in preliminary form, the register is a tremendously useful resource to investigators of biodiversity in the Gulf of Maine.
For example, it provides a baseline against which scientists can monitor future losses or introductions of species in the region as a result of climate change or other events, whether natural or induced by humans. Because the Gulf of Maine lies in an area that transitions from subpolar to temperate conditions, it and its creatures may serve as a sentinel for climate change. And, by providing a more complete picture of the marine web of life, it is another step toward managing the Gulf of Maine as an ecosystem – one of the primary goals of fisheries laws in the U.S. and Canada and of recent ocean commissions.
"Though the Gulf of Maine is one of the most intensively studied bodies of water in the world, there has never been an undertaking to compile all species living there. This register is the first comprehensive list of organisms living in the Gulf of Maine, and the count clearly exceeds the commonly bandied projection of approximately 2000 species" according to Van Guelpen.
Incze emphasized that, while the register is the regions first comprehensive, authoritative list of known species, it is a work in progress. For example, just outside of the Gulf of Maine proper, seaward of Georges Bank, scientists exploring a chain of extinct, undersea volcanoes known as the New England Seamounts are finding both species that are likely new to science and species whose existence has been known on the eastern side of the Atlantic but never before seen in the Gulf of Maine region. "And," he said, "there are likely thousands more species throughout the Gulf of Maine not yet identified. These include small worms and other organisms living in the soft sediments that cover much of the sea floor and microscopic bacteria and viruses that live throughout the ecosystem. While most are invisible to the human eye, they are collectively major players in the web of ocean life."
The Census of Marine Life is a global network of researchers in more than 70 nations engaged in a ten-year initiative to assess and explain the diversity, distribution, and abundance of marine life in the oceans -- past, present, and future. The Gulf of Maine Census, which is based at the University of Southern Maine, is one of 17 projects worldwide and serves as a demonstration of how to undertake a census in a large marine ecosystem.
Interesting facts derived from the Gulf of Maine Register of Marine Species
- Marine species in the Gulf of Maine range from miniscule, like the diatoms, to gigantic, the largest being the blue whale. The smallest species, like the phytoplanktonic diatoms and dinoflagellates, number in the billions, while the larger species can be rare, such as the right whale, of which there are only a few hundred in the Gulf of Maine.
- Like summer tourists, at least 18 species of marine mammals spend only part of the year in the Gulf of Maine. One of the more famous is the humpback whale, whose Latin name Megaptera novaeangliae means "big-winged New Englander." Whales migrate to colder waters for feeding in the summer, and to tropical waters to give birth in the winter.
- Mammals like the humpback whale are at the top of the marine food chain and depend on multiple species lower in the chain. For example, a humpback whale may need to eat a ton of herring (about 5,000 fish). Each herring has fed on hundreds of zooplankton (animals that float with the currents), such as shrimp-like species called krill. And each krill has fed on as many as 130,000 diatoms. Therefore, one meal for a humpback may represent more than 400 billion diatoms. (Cerullo, M., 1999, Sea Soup, p. 14).
- The oldest described species in the register is from 1753, a green alga called Ulva lactuca, commonly known as sea lettuce. The newest organisms to science are five species of flatworms which were described in 2003. Recent and planned exploration of the New England Seamounts may yield new species, but most certainly will provide first records of plants or animals found in other parts of the world, such as the Mid-Atlantic Ridge or the eastern North Atlantic.
- We associate corals with warm tropical waters rather than the cold Gulf of Maine. But the Gulf of Maine region hosts 14 known species of deepwater coral, some of which have only recently been found by Gulf of Maine scientists.
- Species of animals without backbones (invertebrates), including sponges, jellyfish, worms, mollusks, echinoderms such as starfish, sea urchins and sand dollars, and crustaceans, outnumber those with backbones, such as fishes, birds, and mammals, almost 2-to-1 (1,669 invertebrate species v. 914 vertebrate).
- Nearly one-quarter of all known species – 733 in all -- in the Gulf of Maine region are plants (aquatic, photosynthetic organisms, ranging from single-celled forms to kelp, that are the base of the marine food chain). Most are tiny. One teaspoon of seawater can hold more than a million phytoplankton (tiny plants that float with currents). Phytoplankton also are the species that give otherwise blue oceans (reflecting the color of the sky) their varying colors.
- Two of the microscopic plant species are of the genus Alexandrium and are the source of the paralytic shellfish poisoning known as "red tide." A major red tide swept the New England coast in 2005, shutting down the clamming industry for weeks.
- What New Englanders call the "steamer, "long-neck," squirt clam," or "belly clam" – or simply "the clam" -- is a species formally known as Mya arenaria and commonly known as the soft-shelled clam. It is one of 110 known species of bivalves in the Gulf of Maine region, a class of species that also includes mussels, quahogs, and scallops.
- One of the Gulf of Maines tastiest delights, the American lobster, is just one species among 441 species known as arthropods – creatures with jointed appendages and hard outer shells. While the human species loves lobster, other mammalian species, in particular whales, depend on different arthropods, such as the tiny crustaceans called copepods and krill.
- Twenty percent of known marine species in the Gulf of Maine region – a total of 652 -- are fishes. Of these, fewer than 5 percent are fished commercially. For an animated map that shows the decline of some of the best known of these, such as cod and haddock, see the Gulf of Maines Dynamic Atlas at: http://gmbis.iris.usm.maine.edu/products.asp Some species are recently arrived as the result of human activities, such as shipping, and are unwelcome invaders that are altering local ecosystems. These include the European green crab, a small shore crab that is an efficient colonizer and predator.
Suzy Ryan | EurekAlert!