Esteves-Amador, René F.
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Publication Short-term changes to the coral reef fish community structure following the regional coral bleaching event of 2005(2013) Esteves-Amador, René F.; García-Saís, Jorge R.; College of Arts and Sciences - Sciences; Appeldoorn, Richard; Armstrong, Roy; Nemeth, Richard; Kubaryk, John; Department of Marine Sciences; Wessel Beaver, LindaVarious studies have quantified the loss of live coral as a result of the bleaching event of 2005 in the Caribbean; yet, there is a lack of information as to how the reef fish community has responded. Based on annual visual surveys along permanent belttransects on two oceanic and three neritic reef sites along the west and south coast of Puerto Rico between 1999 and 2011, the present study determines the extent of how reef fish communities reacted to this recent regional disturbance. The study was divided in three components: (1) providing an “a-posteriori” analysis of distance from shore, rugosity, live coral, algae and depth as sources of variability or dissimilarity between the multispecies fish assemblages prior to the 2005 bleaching event, (2) identify changes of reef fish community structure on individual reef as measured by the variations of species diversity, abundance and taxonomic composition before and after the 2005 coral bleaching event, and (3), evaluating the implications of apparent losses in live coral cover following the large scale 2005 bleaching event on the pre-bleaching spatial variability patterns of fish community structure between surveyed reefs. An MDS resemblance matrix based on the ordination of species abundance showed strong affinity among replicate transects within most reef stations and two main patterns, one that separated reef stations of the oceanic islands Mona and Desecheo from insular shelf stations, and another that separated 10 m from 30 m depth stations across all locations. A Canonical Correspondence Analysis showed that the combined effects of distance from shore, rugosity, algae, depth, and live coral sufficiently explained up to 78.9% of the spatial variability of reef fish community structure. Fluctuations of fish species richness and abundance where live coral cover remained stable resembled those observed on monitored reef stations with significant declines of live coral cover suggesting fish assemblages were resilient to benthic habitat changes. The characteristic trophic structure of neritic and oceanic reef station clusters persisted through time despite substantial variations of the relative percentage within trophic functional groups suggesting that processes shaping fish communities become less probabilistic as spatial scale increases.Publication Dispersal of reef fish larvae from known spawning sites in la Parguera(2005-12) Esteves-Amador, René F.; García-Saís, Jorge R.; College of Arts and Sciences - Sciences; Yoshioka, Paul M.; Capella, Jorge E.; Aponte, Nilda E.; Department of Marine Sciences; Ojeda, EdgardoThe objective of this study was to examine potential dispersal trajectories of mutton snapper (Lutjanus analis) eggs and early stage larvae during spawning events at La Parguera. Larval fishes were collected during four cruises between March and May 2003 along three transects running perpendicular to the shelf-edge. The Acoustic Doppler Current Profiler (ADCP) velocity profile Vertical velocity structure and temperature variations during the April 17 lunar perigee-zizygy event suggest that an internal wave collided with the shelf, resulting in an influx of deeper colder water, while displacing near-surface waters out to the Caribbean Sea. The mean westward flow of 7.3 km per day favors eggs and planktonic larvae spawned at the shelf-edge being transported offshore. However, the surface flow follows the bathymetry northward potentially leading to final recruitment destinations along the west coast of the island during spring 2003.