Entity

Time filter

Source Type

Miami Lakes, FL, United States

Toth L.T.,Florida Institute of Technology | van Woesik R.,Florida Institute of Technology | Murdoch T.J.T.,Bermuda Zoological Society | Smith S.R.,Bermuda Aquarium Museum and Zoo | And 3 more authors.
Coral Reefs | Year: 2014

With coral populations in decline globally, it is critical that we tease apart the relative impacts of ecological and physical perturbations on reef ecosystems to determine the most appropriate management actions. This study compared the trajectories of benthic assemblages from 1998 to 2011 in three no-take reserves and three sites open to fishing, at 7-9 and 15-18 m depth in the Florida Keys. We evaluated temporal changes in the benthic assemblage to infer whether fisheries bans in no-take reserves could have cascading effects on the benthos in this region. Coral cover declined significantly over time at our sites and that trend was driven almost exclusively by decline of the Orbicella (formerly Montastraea) annularis species complex. Other coral taxa showed remarkable stasis and resistance to a variety of environmental perturbations. Protection status did not influence coral or macroalgal cover. The dynamics of corals and macroalgae in the 15 years since the reserves were established in 1997 suggest that although the reserves protected fish, they were of no perceptible benefit to Florida's corals. © 2014 Springer-Verlag Berlin Heidelberg. Source


Precht W.F.,Dial Cordy and Associates Inc. | Miller S.L.,Nova Southeastern University | Chiappone M.,Nova Southeastern University
Bulletin of Marine Science | Year: 2014

The 1983-1984 Caribbean-wide mass mortality of the once ubiquitous long-spined sea urchin Diadema antillarum Philippi, 1845, is one of several factors considered responsible for coral reef change throughout the region. Unfortunately, there is a paucity of pre-mortality event density data for D. antillarum in the Florida Keys, making it difficult to determine pre-1983 population density levels. Results from surveys conducted during 1970-1973 in the lower Florida Keys, in shallow (<12 m) fore reef habitats, yielded relatively abundant and widespread D. antillarum densities in qualitative transects at five reefs prior to the 1983-1984 die-off. In quantitative surveys at one reef, Middle Sambo Reef in 1972, up to 7.9 individuals m-2 were recorded using quadrats in high-relief spur and groove habitat. A second mortality event in the Florida Keys, beginning in April 1991, again depressed urchin densities that had begun to recover from the 1983-1984 mass mortality. By 1992, D. antillarum densities (<0.01 m-2) were two orders of magnitude lower than pre-die-off estimates (range of 0.07-0.57 m-2 from several spur and groove reefs in the lower Florida Keys) and remained so through 2009. The pre-mortality echinoid density estimates detailed in the Florida Keys provide a baseline to compare with their current population status and should help inform managers about realistic recovery or restoration targets for D. antillarum.. Source


Bruno J.F.,University of North Carolina at Chapel Hill | Precht W.F.,Dial Cordy and Associates Inc. | Vroom P.S.,National Oceanic and Atmospheric Administration | Aronson R.B.,Florida Institute of Technology
Marine Pollution Bulletin | Year: 2014

Identifying the baseline or natural state of an ecosystem is a critical step in effective conservation and restoration. Like most marine ecosystems, coral reefs are being degraded by human activities: corals and fish have declined in abundance and seaweeds, or macroalgae, have become more prevalent. The challenge for resource managers is to reverse these trends, but by how much? Based on surveys of Caribbean reefs in the 1970s, some reef scientists believe that the average cover of seaweed was very low in the natural state: perhaps less than 3%. On the other hand, evidence from remote Pacific reefs, ecological theory, and impacts of over-harvesting in other systems all suggest that, historically, macroalgal biomass may have been higher than assumed. Uncertainties about the natural state of coral reefs illustrate the difficulty of determining the baseline condition of even well studied systems. © 2014 Elsevier Ltd. Source


COte I.M.,Simon Fraser University | Precht W.F.,Dial Cordy and Associates Inc. | Aronson R.B.,Florida Institute of Technology | Gardner T.A.,University of Cambridge | Gardner T.A.,International Institute for Sustainability
Marine Pollution Bulletin | Year: 2013

Caribbean reefs have experienced unprecedented changes in the past 40. years. A major hypothesis to explain shifts in reef community composition relates to declining herbivory. This hypothesis was developed largely based on observations of Jamaican reefs from the 1980s onward, but it is widely held to be relevant regionally. We use a region-wide dataset on benthic composition to examine how well the pattern of ecological change on Jamaican reefs is mirrored by other Caribbean reefs. The extent to which macroalgal cover exceeds coral cover on Jamaican reefs is an order of magnitude more extreme than seen elsewhere. We suggest that Jamaican reefs are not representative of the degradation trajectory of Caribbean reefs and management based on the Jamaican experience may not be relevant elsewhere. However, the recovery of Jamaican reefs following the return of urchins gives us hope that Caribbean reefs are more resilient to catastrophic disturbances than previously thought. © 2013 Elsevier Ltd. Source


Hackerott S.,University of North Carolina at Chapel Hill | Valdivia A.,University of North Carolina at Chapel Hill | Green S.J.,Simon Fraser University | Cote I.M.,Simon Fraser University | And 6 more authors.
PLoS ONE | Year: 2013

Biotic resistance, the process by which new colonists are excluded from a community by predation from and/or competition with resident species, can prevent or limit species invasions. We examined whether biotic resistance by native predators on Caribbean coral reefs has influenced the invasion success of red lionfishes (Pterois volitans and Pterois miles), piscivores from the Indo-Pacific. Specifically, we surveyed the abundance (density and biomass) of lionfish and native predatory fishes that could interact with lionfish (either through predation or competition) on 71 reefs in three biogeographic regions of the Caribbean. We recorded protection status of the reefs, and abiotic variables including depth, habitat type, and wind/wave exposure at each site. We found no relationship between the density or biomass of lionfish and that of native predators. However, lionfish densities were significantly lower on windward sites, potentially because of habitat preferences, and in marine protected areas, most likely because of ongoing removal efforts by reserve managers. Our results suggest that interactions with native predators do not influence the colonization or post-establishment population density of invasive lionfish on Caribbean reefs. © 2013 Hackerott et al. Source

Discover hidden collaborations