A STUDY of the BRYOZOA of BEAUFORT, NORTH CAROLINA, and VICINITY Author(S): Frank J
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A STUDY OF THE BRYOZOA OF BEAUFORT, NORTH CAROLINA, AND VICINITY Author(s): Frank J. S. Maturo, Jr. Source: Journal of the Elisha Mitchell Scientific Society , May 1957, Vol. 73, No. 1 (May 1957), pp. 11-68 Published by: North Carolina Academy of Sciences, Inc. Stable URL: https://www.jstor.org/stable/24333918 JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact [email protected]. Your use of the JSTOR archive indicates your acceptance of the Terms & Conditions of Use, available at https://about.jstor.org/terms is collaborating with JSTOR to digitize, preserve and extend access to Journal of the Elisha Mitchell Scientific Society This content downloaded from 86.59.13.237 on Tue, 06 Jul 2021 10:21:00 UTC All use subject to https://about.jstor.org/terms A STUDY OF THE BRYOZOA OF BEAUFORT, NORTH CAROLINA, AND VICINITY1 By Frank J. S. Maturo, Jr. Department of Zoology, Duke University, Durham, N. C. and Duke Marine Laboratory, Beaufort, N. C. Among the host of invertebrates which make up the fouling complex in the sea, the Bryozoa are probably second only to hydroids in the number of species involved. Experiments in recent years have revealed this group as one of the most conspicuous and prevalent components of test surface populations. Yet conspicuous gaps in the recorded distribution of many species occur for want of sufficient faunistic studies. Along the Atlantic coast of North America almost nothing is known about these animals from Chesapeake Bay to the southern tip of Florida and the West Indies. In view of the lack of information on this group the present study was under taken to discover what bryozoans occur in the vicinity of Beaufort, North Caro lina, how they are locally distributed, and their substrate preferences. A sub sequent report will consider their temporal or seasonal distribution, spatial dis tribution, reproductive periods and rates, and the role of environmental factors as related to these. General description of the Beaufort area.—The Beaufort area has figured promi nently in marine biological studies during the last fifty years as a result of the investigations at three marine laboratories there. The suitability of the region for such studies becomes obvious when one considers the wealth of fauna and flora available because of its geographical location and topography. It has been found by numerous workers that the region, which is intermediate between Woods Hole and Florida, is the southern limit along the Atlantic coast for many northern forms and the northern limit for a host of southern species. Historically, the Beaufort region includes not only the immediate inshore areas around Beaufort, North Carolina, but also waters offshore to the Gulf Stream, east to Cape Lookout, and west or southwest to New River Inlet or to Cape Fear. The coast follows a general east-west direction with the Gulf Stream lying about thirty miles offshore. The coastline is separated by offshore islands or outer banks from the ocean proper so that numerous sounds and estuaries are inclosed. The bar-built estuaries and sounds are considered somewhat positive, that is, they possess a measurable dilution of sea water by river water, the mix ing primarily a result of tidal action coupled with a large effect of wind in shal low water. The bottom is composed of mud, sand, and shells, varying from place to place, and extensive marshes, shoals, and oyster reefs are scattered throughout the area. The man-made rock jetties and harbor works, in addition to the shell bottoms, afford excellent habitats for Bryozoa. About 21 miles offshore in 13 to 15 fathoms of water is an extensive series of reefs or "fishing banks." The main bank, as reported by Radcliffe (1914) from 1 Cost of publication partially defrayed by a subsidy from Duke University. 11 This content downloaded from 86.59.13.237 on Tue, 06 Jul 2021 10:21:00 UTC All use subject to https://about.jstor.org/terms 12 Journal of the Mitchell Society [May a survey conducted by the U. S. Fisheries Steamer Fish Hawk, lies in Lat. 34° 19' N., Long. 76° 59' W., and is the largest reef known on the coast. The fauna and flora of these reefs which have been reported from a few meager collections are tropical forms, much the same as in the West Indies. Between the "fishing banks" and the outer banks is a veritable desert as far as bryozoans are con cerned, because the bottom type is only sand, and offers no suitable substrate. However, great masses of seaweed which support a bryozoan fauna are found in this area, carried there by currents from the "fishing banks" and other regions. Thorough reports on the environmental conditions at Beaufort may be found in papers by Hoyt (1920), Gutsell (1930), McDougall (1943), and others. Bryozoan studies on the Atlantic Coast.—Perhaps no area on our Atlantic coast has been studied as thoroughly as the Woods Hole region. Osburn (1912b) has done the major part of the work there and has reviewed studies on Bryozoa of the Atlantic coast up to that time. Later, Osburn (1933) made a survey of the bryozoans of Mount Desert Island, Maine. Rogick has been responsible for most new records from Woods Hole. The works of Hutchins (1945) on Long Island Sound, and Osburn (1932b, 1944) at Chesapeake Bay, complete studies on Bryozoa to the north of Beaufort. Smitt (1872-1873) prepared the earliest important work in the Florida region, his studies being confined primarily to deep water forms. Osburn reported on the bryozoans of the Tortugas Islands (1914), Curacao and the southern Caribbean Sea (1927, 1947), and Puerto Rico (1940). Canu and Bassler (1928) reported the species found in the Gulf of Mexico region. Mention should also be made of a series of papers by Verrill from 1900 to 1902 on the fauna of Bermuda. Studies by Marcus since 1937 have contributed a wealth of information on species found in Brazilian waters. In the Beaufort area, the first records of Bryozoa are those of 17 species re ported by Verrill (1878) in a study of the natural history of Fort Macon, North Carolina, and vicinity, by Coues and Yarrow. Osburn has mentioned a number of species in the area at various times in his reports on other localities. Most of his specimens were collected on the "fishing banks." The seasonal study of McDougall (1943) lists eight species, while the faunistic report of Pearse and Williams (1951) records 24 species from reefs off New River Inlet, North Caro lina. Methods and Materials.—An attempt was made to cover as many ecologi cal situations as possible at various seasons over a two-year period. Bryozoan specimens were collected from shells, rocks, pilings, experimental racks, sub merged debris, and algae which were found around Beaufort, and at Shackle ford, Fort Macon, and Shark Shoal jetties and beaches (see map). Extensive dredgings in the various sounds and Newport River estuary as well as several dredgings and trawlings offshore were made. The most productive source of ma terial was from shells dredged from Bogue Sound in front of Morehead City Port Terminal. A record book was kept in which each collection was catalogued together with habitat information, identifications, and memoranda on particular specimens. This content downloaded from 86.59.13.237 on Tue, 06 Jul 2021 10:21:00 UTC All use subject to https://about.jstor.org/terms 1957] Bryozoa of Beaufort, North Carolina 13 IF "'-«VA/ .·< 'Χ^ λ, «*.·ν.. ^ %*V«. |f·^· r ,,ä· ss ig * A ' '' "^pivers^"^^'^'^AUFORT 'ä 1 .;,·,·.% BOGUE SOUND QU. \ \ /v^ÄJ^N *. ««"<| · .' -.^ν:·:··.·νη<^^, SHARK SHOAL 'i"'-':\.:> ' -*«■. .IFTTY ·.·. · ·. '■>. Ii.'· .,·...si BOGUEB06UE BANKSBANKS E3ESa3SBSS®B5E^^ ivy i-;^: v. ^; v!>' J^k:· ■«if ; T' BEAUFORT INLET V βΑΝΚίBANKS J Map of Beaufort, North Carolina, and vicinity, with notations on the bottom types. This content downloaded from 86.59.13.237 on Tue, 06 Jul 2021 10:21:00 UTC All use subject to https://about.jstor.org/terms 14 Journal of the Mitchell Society [May Specimens were preserved in 70 per cent alcohol for study. In addition, samples of calcareous species were "calcined" for study by the process outlined by Rogick (1945a) or treated with Javelle water as described by Bassler (1953). Whenever possible, living material was studied as well as the preserved material. Occa sionally, a dilute solution of neutral red was used to stain lightly both living and preserved material in order to bring out features of taxonomic importance. The bryozoans were examined under a binocular microscope, and drawings were prepared with the aid of the camera lucida. The author is indebted to the late Dr. R. C. Osburn for the loan of additional Beaufort specimens from his personal collection, his identification of a number of specimens, and for the confirmation of the entire collection. Thanks are ex tended to Dr. C. G. Bookhout for placing the many facilities of the Duke Uni versity Marine Laboratory at the writer's disposal, to the North Carolina Insti tute of Fisheries Research for use of necessary equipment, and to Dr. F. A. Chace, Jr., for making available the collections of the U. S. National Museum. Results.—The classification followed below has been adapted primarily from the recent monograph by Osburn (1950-1953) on the Bryozoa of the Pacific coast of North America. The group is herein considered two phyla, the Bryozoa or Ectoprocta and the Entoprocta, according to the studies of Hyman (1951).