Hurricane Allen's Impact on Jamaican Coral Reefs Author(S): J
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Hurricane Allen's Impact on Jamaican Coral Reefs Author(s): J. D. Woodley, E. A. Chornesky, P. A. Clifford, J. B. C. Jackson, L. S. Kaufman, N. Knowlton, J. C. Lang, M. P. Pearson, J. W. Porter, M. C. Rooney, K. W. Rylaarsdam, V. J. Tunnicliffe, C. M. Wahle, J. L. Wulff, A. S. G. Curtis, M. D. Dallmeyer, B. P. Jupp, M. A. R. Koehl, J. Neigel and E. M. Sides Reviewed work(s): Source: Science, New Series, Vol. 214, No. 4522 (Nov. 13, 1981), pp. 749-755 Published by: American Association for the Advancement of Science Stable URL: http://www.jstor.org/stable/1686954 . Accessed: 20/09/2012 16:01 Your use of the JSTOR archive indicates your acceptance of the Terms & Conditions of Use, available at . http://www.jstor.org/page/info/about/policies/terms.jsp . 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]. American Association for the Advancement of Science is collaborating with JSTOR to digitize, preserve and extend access to Science. http://www.jstor.org 13 November 1981, Volume 214, Number 4522 -SCIENCE createda naturalexperiment of Goreau's thesis (7) that structuraland taxonomic differences between reefs on Jamaica's north and south coasts were due to dif- ferences in hurricanefrequency. In the Hurricane Allen's Impact oIIn last half-century,while Port Royal on the south coast experienced 11 'hurricanes, Jamaican Coral ReelfS Discovery Bay on the north has seen only four; the last severe hurricanewas in 1917 (12). J. D. E. A. P. A. Woodley, Chornesky, Cliffo^rd ' 'On 6 August 1980, Hurricane Allen, J. B. C. Jackson, L. S. Kaufman, N. Knowlton, J. C. LaLng the strongest storm recorded in the Ca- ribbean,passed close to the north coast M. P. Pearson, J. W. M. C. Rooney, K. W. Rylaarsdz Porter, of Jamaica (Fig. 1), severely damaging V. J. Tunnicliffe, C. M. Wahle, J. L. Wulff, A. S. G. Curtis its reefs (13). Winds reached 285 kilome- ters hour at the center and M. D. Dallmeyer, B. P. Jupp, M. A. R. Koehl, J. Neil el per (14), approximately 110 km/hr in Discovery E. M. Sidles Bay, where waves over 12 meters (15) were seen breaking(Fig. 2) in water 15 m deep on the East Fore Reef (Fig. 1, location E). These waves, and the dis- The relative importance of environ- of unusual value for the following rea- lodged materialthat they carried, devas- mentalprocesses that affect the distribu- sons. First, Jamaican c,oral reefs are tated the shallow reefs in Discovery Bay tion of organismsvaries with the intensi- amongthe best known int the world as a (Figs. 3 and 4). Dense stands of Acro- ty and frequency of the processes (1). result, in particular,of thie studies of T. pora palmata colonies (1 to 3 m high), Exposureto wave energy exerts an influ- F. Goreau, his associatles, and subse- which had dominatedthe reef between 0 and a depth of 5 m, were leveled. The breaker zone and reef flat were trans- Summary.Coral reefs of northJamaica, normallysheltered, were severely dam- formed from constructionalreefs into a aged by HurricaneAllen, the strongest Caribbeanhurricane of this cetntury. Immedi- gently sloping rubble rampart, which ate studies were made at DiscoveryBay, where reef populationswere alreadyknown emergedhere and there as islands where in some detail. Data are presented to show how damage variedwith tt he positionand none had been before. Physical distur- orientationof the substratumand withthe shape, size, and mechanic;al propertiesof bance extended even to a depth of 50 m, exposed organisms. Data collected over succeeding weeks showedi strikingdiffer- where some platelike colonies of Agari- ences in the abilityof organisms to heal and survive. cia spp. were damaged,and the sediment normallycovering their bases was tem- porarily washed away. Everywhere ence on communitycomposition of reef quent researchersat the Discovery Bay damagewas inflictednot only by violent- corals, and thus on coral reef structure MarineLaboratory of thee University of ly movingwater (16) but also-bythe solid (2), both directly and through its influ- the West Indies (11). Second, many of objects that it dislodged: rolling corals ence on biological interactions. Reefs these people were at the laboratorydur- (Fig. 4, A and C), suspended fragments differ in their exposure to both routine ing or soon after the storm, and they (Fig. 4B), and scouring sand (Fig. 4D). wave energy and hurricanes(3, 4), but, collected data comparableto those taken The types and magnitudes of damage because hurricanesoccur irregularlyand previously on routine paltterns and pro- varied with reef location, depth, and comparativelyrarely, it is hardto assess cesses. Third, these facttors, combined topography and differed between taxa their relative importance. While hurri- with the -severity of Huirricane Allen, according to their location, form, and canes can cause violent disturbanceto coral reefs with extreme short- (5) and The authorswere residentor visitinginvestigators present at the DiscoveryBay MarineLaboratory during or soon after the hurricane.Their institutionalaffiliations were at the time as follows: J. D. Woodley, long-term(3, 4, 6-9) effects, very little is DiscoveryBay MarineLaboratory, Discovery Bay, Jamaica;M. C. Rooney and E. M. Sides, Departmentof known of their immediate Zoology, and B. P. Jupp,Department of Botany, Universityof the West Indies, Kingston7, Jamaica;E. A. consequences Chornesky,Division of BiologicalSciences, and J. C. Lang, MarineScience Institute,University of Texas, for previously investigated populations Austin78712; P. A. Clifford,Hampshire College, Amherst,Massachusetts 01002; J. B. C. Jackson, K. W. Rylaarsdam,and C. M. Wahle, Departmentof Earth and PlanetarySciences, Johns Hopkins University, (10). In this article, we present data on Baltimore,Maryland 21218; L. S. Kaufman,Biology Department,University of Massachusetts,Boston the types and magnitudes of damage 02125;N. Knowltonand J. L. Wulff, Departmentof Biology, Yale University, New Haven, Connecticut 06520;M. P. Pearson,Department of Zoology, and A. S..G. Curtis,Department of Cell'Biology,University done by Hurricane Allen to the well- of Glasgow,Glasgow G12 8QQ, Scotland;J. W. Porter,M. D. Dallmeyer,and J. E. Neigel, Departmentof studied coral reefs of north Jamaica. Zoology,University of Georgia,Athens 30602; V.-J. Tunnicliffe,Institute of OceanSciences, Sidney, British Columbia,V8L 4B2, Canada;M. A. R. Koehl, Departmentof Zoology, Universityof California,Berkeley We believe that these observationsare 94720. SCIENCE,VOL. 214, 13 NOVEMBER1981 0036-8075/81/1113-0749$01.00/0Copyright ? 1981AAAS 749 construction. We consider first the ef- cane track (Fig. 1), suffered most heavily and injury of arborescent gorgonians (18) fects of spatial factors and then describe (17). West of this region, at Discovery were greater among exposed, shallow the immediate impact on common organ- Bay (Fig. 1), damage was more severe on colonies at Gorgo City (Fig. 1, location isms and their subsequent responses the exposed East Fore Reef than on the B) than among those in the protected over the following 7 months. West Fore Reef (Fig. 1, location C), West Back Reef (Fig. 1, location G), where breaking waves were only half as where no significant increase in injury high (15), and damage was much less was seen (Table 1, rows 1 and 2; X2 Spatial Patterns of Damage severe in back reef areas sheltered by the values for the increase in death and reef crest. For example, wholesale tum- injury at Gorgo City are 149 and 33). Damage was patchy on several scales, bling and shattering of head corals oc- At any single locality, dissipation of varying regionally around Jamaica, lo- curred locally at depths of 14 m on the wave impact depended on aspects of the cally between reefs and reef zones, and East Fore Reef (Fig. 4A); similar devas- local reef profile, including depth, slope, within zones. Not all patchiness can be tation did not occur below a depth of 7 m and shelf width. Shallow fore-reef areas easily explained, but a number of pat- on the West Fore Reef or at any depth were generally more severely damaged terns emerge. The northeast coast of within Discovery Bay. Similarly, in- than deep ones. We see this most direct- Jamaica, which was closest to the hurri- creases over routine frequencies of death ly by comparing the same species on the same reefs at different depths. For exam- ple, head corals were more frequently toppled in sand channels in 10 m of water than in 14 m (Table 1, compare rows 5 and 6; x2 for numbers toppled and not toppled after Hurricane Allen = 4.75, P < .05). Similarly, densities of the ur- chin Diadema antillarum were reduced more in shallow areas (Table 1, rows 13 to 17). Similar decrease in damage with increasing depth is evident for all corals combined (Table 1, compare rows 8 and 9). Sloping or level reef surfaces were more severely affected than vertical ones. At West Rio Bueno (Fig. 1, loca- tion A), where the reef is vertical below a depth of 8 m, little mortality was seen in marked quadrats of largely foliaceous corals at depths of 10, 15, and 20 m (Table 1, rows 10 to 12), in contrast to the toppling of the more massive head corals observed at comparable depths on the sloping West Fore Reef (Table 1, rows 5 to 7). A broad terrace dissipated more wave energy than a narrow one. In the southwest corner of the broad East Fore Reef (Fig. 1, location F) more A. palmata colonies remained erect at a depth of 3 m than on the narrow West Fore Reef where they were leveled.