Profound ecological changes are occurring on coral reefs throughout the tropics, with marked coral cover losses and concomitant algal increases, particularly in the Caribbean region. Historical declines in the abundance of large Caribbean reef fishes likely reflect centuries of overexploitation. However, effects of drastic recent degradation of reef habitats on reef fish assemblages have yet to be established. By using meta-analysis, we analyzed time series of reef fish density obtained from 48 studies that include 318 reefs across the Caribbean and span the time period 1955-2007. Our analyses show that overall reef fish density has been declining significantly for more than a decade, at rates that are consistent across all subregions of the Caribbean basin (2.7% to 6.0% loss per year) and in three of six trophic groups. Changes in fish density over the past half-century are modest relative to concurrent changes in benthic cover on Caribbean reefs. However, the recent significant decline in overall fish abundance and its consistency across several trophic groups and among both fished and nonfished species indicate that Caribbean fishes have begun to respond negatively to habitat degradation.

Mesophotic coral ecosystems (MCEs) are characterized by the presence of light-dependent corals and associated communities that are typically found at depths ranging from 30 to 40 m and extending to over 150 m in tropical and subtropical regions. The dominant communities providing structural habitat in the mesophotic zone can be comprised of coral, sponge, and algal species. Because working in this depth range is constrained by traditional SCUBA limits, less is known about corals and associated organisms there compared to shallower coral communities. Following the first-ever gathering of international scientists to review and discuss existing knowledge of MCEs, this issue focuses on the ecological characterization, geomorphology, and concept of MCEs as refugia for shallow-water populations. The review and research papers comprising this special issue reflect the current scientific understanding of these ecosystems and the underlying mechanisms that regulate them, as well as potential resource management implications. It is important to understand the value and role of mesophotic coral ecosystems in tropical and subtropical regions as these areas face increasing environmental change and human impacts Keywords Mesophotic coral ecosystem Á Biodiversity Á Geomorphology Á Connectivity Á Community structure Á Resource management Mesophotic coral ecosystem workshopOn 12-15 July 2008, a scientific workshop was held in Jupiter, Florida, to identify critical research and resource management needs for mesophotic coral ecosystems

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The Second International Mesophotic Coral Ecosystems (MCEs) workshop was held in Eilat, Israel, October 26-31, 2014. Here we provide an account of: (1) advances in our knowledge of MCE ecology, including the central question of the potential vertical connectivity between MCEs and shallow-water reefs (SWRs), and that of the validity of the deep-reef refugia hypothesis (DRRH); (2) the contribution of the 2014 MCE workshop to the central question presented in (1), as well as its contribution to novel MCE studies on corals, sponges, fish, and crabs; and (3) gaps, priorities, and recommendations for future research stemming from the workshop. Despite their close proximity to well-studied SWRs, and the growing evidence of their importance, our scientific knowledge of MCEs is still in its infancy. During the last five years, we have witnessed an ever-increasing scientific interest in MCEs, expressed in the exponential increase in the number of publications studying this unique environment. The emerging consensus is that lower MCE benthic assemblages represent unique communities, either of separate species or genetically distinct individuals within species, and any significant support for the DRRH will be limited to upper MCEs. Determining the health and stability of MCEs, their biodiversity, and the degree of genetic connectivity among SWRs and MCEs, will ultimately indicate the ability of MCEs to contribute to the resilience of SWRs and help to guide future management and conservation strategies. MCEs deserve therefore management consideration in their own right. With the technological advancements taking place in recent years that facilitate access to MCEs, the prospects for exciting and innovative discoveries resulting from MCE research, spanning a wide variety of fields, are immense.

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Ecologists have paid increasing attention to the design of marine protected areas (MPAs), and their design advice consistently recommends representing all habitat types within MPAs or MPA networks as a means to provide protection to all parts of the natural ocean system. Recent developments of new habitatmapping techniques make this advice more achievable, but the success of such an approach depends largely on our ability to define habitat types in a way that is ecologically relevant. We devised and tested the ecological relevance of a set of habitat-type definitions through our participation in a stakeholder-driven process to design a network of MPAs, focusing on no-take marine reserves in the Seaflower Biosphere Reserve, San Andrés Archipelago, Colombia. A priori definitions of habitat types were ecologically relevant, in that our habitat-type definitions corresponded to identifiable and unique characteristics in the ecological communities found there. The identification of ecological pathways and connectivity among habitats also helped in designing ecologically relevant reserve boundaries. Our findings contributed to the overall design process, along with our summary of other general principles of marine reserve design. Extensive stakeholder input provided information concerning the resources and their patterns of use. These inputs also contributed to the reserve design process. We anticipate success for the Seaflower Biosphere Reserve at achieving conservation and social goals because its zoning process includes detailed yet flexible scientific advice and the participation of stakeholders at every step.Diseño deÁreas Marinas Protegidas Efectivas en la Reserva de la Biosfera Seaflower, Colombia, en Base a Información Biológica y Sociológica Resumen: Los ecólogos han puesto mayor atención en el diseño deáreas marinas protegidas (AMP), y sus sugerencias de diseño recomiendan consistentemente la representación de todos los tipos de hábitat en los AMP o en las redes de AMP como una forma de proporcionar protección a todas las partes del sistema oceánico natural. Desarrollos recientes de técnicas de mapeo de hábitat nuevas hacen que estas recomendaciones sean

Studies of lionfish feeding ecology seek to document the ecological impact of this invasive predatory species and determine which native prey species are at greatest risk. There are 2 common approaches to feeding ecology through gut content analysis: morphological identification to the lowest possible taxonomic rank and/or DNA barcoding of individual prey components in the stomach. The major disadvantage of both techniques is their inability to use advanced digested material. This study introduces next-generation sequencing to lionfish feeding ecology, employing DNA metabarcoding to analyze all components of the gut contents, including the previously unidentifiable portion. Sixty-three lionfish were caught from the inshore and offshore reefs of La Parguera, Puerto Rico. Stomach contents were separated into 2 sample componentsa liquid (i.e. digested) and undigested tissue. A 313 bp region of the cytochrome oxidase subunit I (COI) gene was amplified from extracted DNA using specific primers for Caribbean reef fish. Samples were sequenced with an Illumina MiSeq platform, and the resulting 950+ sequences were compared against GenBank and the Barcode of Life Database to identify specimens at the lowest taxonomic level. Thirty-nine fish species from 16 families were identified (35 each in the digested and tissue fractions), including members of Pomacentridae, Acanthuridae, Gobiidae, Apogonidae, and Scaridae. Using the digested liquiform material proved efficient in detecting prey species, especially those that would have been missed with traditional methods.

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