Biodiversity of Bear Seamount, New England Seamount Chain: Results of Exploratory Trawling
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W&M ScholarWorks VIMS Articles Virginia Institute of Marine Science 9-2003 Biodiversity of Bear Seamount, New England Seamount chain: Results of exploratory trawling JA Moore M Vecchione R Gibbons JK Galbraith M Turnipseed Virginia Institute of Marine Science See next page for additional authors Follow this and additional works at: https://scholarworks.wm.edu/vimsarticles Part of the Aquaculture and Fisheries Commons, and the Marine Biology Commons Recommended Citation Moore, JA; Vecchione, M; Gibbons, R; Galbraith, JK; Turnipseed, M; Southworth, M; and Watkins, E, Biodiversity of Bear Seamount, New England Seamount chain: Results of exploratory trawling (2003). Journal of Northwest Atlantic Fishery Science, 31, 363-372. https://scholarworks.wm.edu/vimsarticles/1970 This Article is brought to you for free and open access by the Virginia Institute of Marine Science at W&M ScholarWorks. 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Authors JA Moore, M Vecchione, R Gibbons, JK Galbraith, M Turnipseed, M Southworth, and E Watkins This article is available at W&M ScholarWorks: https://scholarworks.wm.edu/vimsarticles/1970 J Northw Atl Fish Sci, Vol 31: 363372 Biodiversity of Bear Seamount, New England Seamount Chain: Results of Exploratory Trawling J A Moore Florida Atlantic University, Honors College, Jupiter, FL 33458, USA M Vecchione, B B Collette and R Gibbons National Marine Fisheries Service, National Systematics Laboratory, National Museum of Natural History, Smithsonian Institution, Washington, DC 20560 K E Hartel Museum of Comparative Zoology, Harvard University, Cambridge, MA 02138, USA J K Galbraith National Marine Fisheries Service, Northeast Fisheries Science Center, Woods Hole, MA 02453, USA M Turnipseed, M Southworth, and E Watkins Virginia Institute of Marine Sciences, Gloucester Point, VA 23062, USA Abstract Bear Seamount (39o55'N 67o30'W) is an extinct undersea volcano located inside the US Exclusive Economic Zone south of Georges Bank The fauna associated with the seamount was little known until twenty trawl stations were made 27 December 2000, by the NOAA ship R/V Delaware II The objective of the survey was to begin to document the biodiversity on and over the seamount, particularly of fishes, cephalopods, and crustaceans Representatives of most species were preserved as vouchers and for subsequent definitive identification This report presents a description of the biodiversity A total of at least 274 species were collected Preliminary identifica- tions indicate the capture of 115 fish species Among these were a number of new fish records for the area or rare species, including Acromycter pertubator (Congridae), Diastobranchus capensis (Synaphobranchidae), Alepocephalus bairdii (Alepocephalidae), Mirognathus normani (Alepocephalidae), Bathygadus favosus (Bathygadidae), Nezumia longebarbata (Macrouridae), Gaidropsarus argentatus (Phycidae), Dibranchus tremendus (Ogcocephalidae) and Kali indica (Chiasmodontidae) Only two fish species of potential commercial importance were encountered: Coryphaenoides rupestris and Macrourus berglax" Cephalopods comprised 26 species from 15 families, including one new distributional record and several rarely-collected species The crusta- cean fauna was diverse with at least 46 species Totals for other invertebrate species are pending laboratory identification, but number at least 87 species from 10 Phyla This includes a number of new distributional records and a new species of gorgonian Key words: biodiversity, deep-sea, fauna, fishes, invertebrates, North Atlantic, seamount Introduction ate structural habitat diversity and likely create es- sential habitats for some deep-sea fishes and crusta- Seamounts represent biological islands in the deep ceans1 sea and often feature characteristic faunas that are quite different from those found in the surrounding The New England Seamounts (NES) make up the soft sediment and abyssal habitats1 Large depth ranges, longest seamount chain in the North Atlantic, encom- hard substrates, steep gradients, complex topography, passing more than 30 major volcanic peaks extend- impinging currents, topographically induced ing southeast from Georges Bank for about 1 200 km upwellings, clear oceanic water, and geographic iso- to the eastern end of the Bermuda Rise, ending lation all combine to make seamounts specialized abruptly with Nashville Seamount to the East North habitats for deep-sea organisms (Rogers, 1994)1 The East of Bermuda (Fig1 1)1 The major peaks of the NES benthic fauna on seamounts include species that cre- rise as much as 4 000 m above the Sohm Abyssal Plain1 364 J1 Northw1 Atl1 Fish1 Sci1, Vol1 31, 2003 700° 65° 60° 55° 40° 35° Fig 1 Bathymetric chart of the New England Seamount chain showing depth contours (m) (from Houghton et al, 1977) About 300 km east of Nashville Seamount, the Cor- A review of the biogeography of seamount fauna ner Rise Seamounts form a cluster of peaks midway around the world (Wilson and Kaufman, 1987) makes between the eastern end of the NES and the Mid At- note of only one species known from the entire NES lantic Ridge1 The NES and Corner Rise Seamounts chain (the stony coral Enallopsammia rostrata from resulted from a mantle-plume hotspot, which moved Gregg Seamount)1 Because of this dearth of biotic in- towards the Mid Atlantic Ridge and currently resides formation, the NES was excluded from a recent dis- underneath Great Meteor Seamount (Sleep, 1990)1 cussion on the biology of seamounts around the world (Rogers, 1994)1 The NES chain lies roughly perpendicular to two major currents, the Gulf Stream, flowing to the north- Examinations by one of us (JAM) of archived east, and the Deep Western Boundary Current, which photos taken during the geological investigation of flows southwesterly along the continental slope (Ham- the NES has found that more than 50 species of in- ilton et al1, 1996)1 In addition, the Antarctic Bottom vertebrates and at least eight species of fishes do in Water flows around the bases of the seamounts at the fact live on these seamounts1 Exploratory commer- eastern end of the chain1 These seamounts alter the cial fishing in 1997 on Bear Seamount (the closest flow of the currents in their vicinity (Vastano and NES to the U1S1) captured another seven fish species, Warren, 1976; Hogg et al1, 1986), which may influence including two species previously known from the east- the recruitment of benthic and pelagic organisms1 ern Atlantic (Hydrolagus pallidus and Bathypterois dubius) and one previously found only in the temper- While the geology of the NES and the effects of ate southern hemisphere (Diastobranchus capensis; the seamounts on the Gulf Stream have been exten- Moore et al1, 2003)1 Clearly, much can be done to sively studied, the biota has been almost completely investigate the NES fauna and integrate that infor- ignored (Zeigler, MS 1955; Uchupi et al1, 1970; mation into the extensive knowledge gained from Vastano and Warren, 1976; Houghton et al1, 1977; other seamounts in the Atlantic, Pacific, and elsewhere Heirtzler et al1, MS 1977 and 1977; Hogg et al1, 1986)1 in the world1 MOORE et al1: Biodiversity of Bear Seamount 365 With the increase of deep-sea fisheries, interest MS 1962), two Alvin dives in 1968 (Alvin dive 286 in commercially fishing seamounts has increased and 287), and a commercial exploratory trawl by the (Koslow, 1997)1 Yet seamounts hold concentrations F/V Matthew Melissa out of Stonington, Connecti- of sessile suspension-feeding invertebrates, such as cut, in 19971 A list of taxa identified from these pre- scleractinians, gorgonians and sponges, that add struc- vious studies is given in Table 11 tural complexity, and there are concerns about the im- pact of fishing activities on these invertebrates Prior to our first cruise in 2000, several inverte- (Dayton et al1, 1995; Auster et al1, 1996; Probert et brates and a few fishes were identified from archived al1, 1997; Koslow and Gowlett-Holmes, MS 1998; photos from Atlantis cruise A-281 and Alvin dives 286 Moore and Mace, 1999; Koslow et al1, 2000)1 A re- and 2871 The archived photos are available at the cent haul of Darwin's roughy (Gephyroberyx darwini, Document Library of Woods Hole Oceanographic also known as big roughy) from a canyon on the south Institution1 In addition, several fish specimens were side of Georges Bank generated renewed interest by acquired from a commercial trawler that conducted a some U1S1 fishers in exploring the deepwater fishery few deepwater exploratory tows on the top of Bear resources of New England1 One fishing company put Seamount in 19971 These specimens are deposited at forward a specific proposal to explore the fishery re- the Ichthyology Collection of the Peabody Museum sources on Bear Seamount1 This coincided with plan- of Natural History, Yale University1 ning by the National Marine Fisheries Service (NMFS) to conduct an exploratory survey to Bear Seamount Materials and Methods in late-20001 One objective of this survey was to be- gin to document the biodiversity on and over the Twenty hauls were made on or over Bear seamount, particularly of fishes, cephalopods, and Seamount using double-warp gear towed from the crustaceans before large-scale commercial fishing be- NOAA vessel R/V Delaware II from 27 December gins1 Knowledge of the fauna associated with the 2000 (cruise DE00-11)1 Of these hauls, 11 were fully seamounts is considered crucial in assessing the