Is Acropora Palmata recovering? A case study in Los Roques National Park, Venezuela

Eight years ago (2007), the distribution and status of Acropora palmata was quantified throughout Los Roques archipelago in Venezuela. The aim was to produce a baseline study for this species which combined population genetics with demographic data. The results highlighted that A. palmata had the potential to recover in at least 6 out of 10 sites surveyed. Recovery potential was assumed to be high at sites with a relatively high abundance of the coral, low disease prevalence, high genetic diversity, and high rates of sexual reproduction. However, as noted, Zubillaga et al. (2008) realized recovery was still strongly dependent on local and regional stressors. In 2014 (this study), the status of A. palmata was re-evaluated at Los Roques. We increased the number of sites from 10 in the original baseline study to 106. This allowed us to assess the population status throughout the entirety of the MPA. Furthermore, we also identified local threats that may have hindered population recovery. Here, we show that A. palmata now has a relatively restricted distribution throughout the park, only occurring in 15% of the sites surveyed. Large stands of old dead colonies were common throughout the archipelago; a result which demonstrates that this species has lost almost 50% of its original distribution over the past decades. The majority of corals recorded were large adults (∼2 m height), suggesting that these older colonies might be less susceptible or more resilient to local and global threats. However, 45% of these surviving colonies showed evidence of partial mortality and degradation of living tissues. Interestingly, the greatest increase in partial mortality occurred at sites with the lowest levels of protection (${X}_{o}^{2}=5.4> {X}_{c}^{2}=4.5$; df = 4, p {X}_{\mathrm{cri}}^{2}=1 5.5$; df = 8; p < 0.05) in the density of A. palmata in sites that had previously been categorized as having a high potential for recovery. One explanation for this continued decline may be due to the fact that over the past 10 years, two massive bleaching events have occurred throughout the Caribbean with records showing that Los Roques has experienced unprecedented declines in overall coral cover. We therefore conclude that although local protection could promote recovery, the impacts from global threats such as ocean warming may hamper the recovery of this threatened species

Mainstreaming marine biodiversity into the SDGs: The role of other effective area-based conservation measures (SDG 14.5)

This article explores the concept of “other effective area-based conservation measures” (OECMs) in the context of the UN Convention on Biological Diversity (CBD) Aichi Biodiversity Target 11 on marine protected areas and OECMs and its linkages to the Sustainable Development Goals (SDGs). It argues that mainstreaming biodiversity through CBD Aichi Biodiversity Targets’ implementation into the SDGs can contribute to a more systemic and comprehensive implementation of SDG 14.5 on conservation of at least 10% of marine and coastal areas. It argues that OECMs can complement MPAs and contribute to ecologically representative and effectively managed marine protected areas systems integrated into broader governance systems such as marine spatial planning. Selected global and local sectoral conservation measures are therefore highlighted in this analysis as potential forms of OECMs. At the local level, a case study of ecologically or biologically significant marine areas managed as locally managed marine areas (LMMAs) in Mozambique is discussed. This case study explores how multiple-use LMMAs, which respond to short-term fisher's needs and targeted biodiversity conservation, could contribute to the achievement of specific SDGs on food security, poverty elimination and resilient ecosystems if properly supported by long-term investments, strong institutions and integrated oceans management

Vertical Zoning in Marine Protected Areas: Ecological Considerations for Balancing Pelagic Fishing with Conservation of Benthic Communities

Marine protected areas (MPAs), ideally, manage human uses that threaten ecosystems, or components of ecosystems. During several recent MPA designation processes, concerns have arisen over the scientific justification for no-take MPAs, particularly those that restrict recreational fishing for pelagic species. An important question is: under what conditions might recreational pelagic fishing be compatible with the conservation goals of an MPA that is primarily focused on benthic Communities? In 2005, an expert workshop of fisheries biologists, marine ecologists, MPA managers, and recreational fishermen was convened by NOAAs National MPA Center to evaluate the limited empirical data on benthic-pelagic coupling and to help provide practical advice on this topic. The participants (i) proposed a preliminary conceptual framework for addressing vertical zoning, (ii) developed preliminary guidelines to consider when evaluating whether to allow or restrict pelagic fishing in an MPA, and (iii) identified future research priorities for understanding benthic-pelagic Coupling. A Suite of ecological conditions where recreational pelagic fishing may not be compatible with benthic conservation were identified: (1) high relief habitats, (2) depths shallower than 50-100 m (depending upon the specific location), (3) major topographic and oceanographic features, and (4) spawning areas. Similarly, pelagic fishing is not likely to affect benthic communities adversely in many circumstances. Until further scientific study can shed more light on the issue of how benthic-pelagic linkages affect specific conservation targets, the proposed framework in this manuscript provides practical, easily-applied guidance for using vertical zoning to manage fishing in multiple use MPAs that focus on benthic conservation.Areas Marinas Protegidas (AMP) idealmente, administran el uso humano que amenaza los ecosistemas o sus componentes. Durante el actual proceso de declaracion de AMP, han surgido algunas preocupaciones acerca de la justificacion cientifica para establecer areas de no pesca, particularmente aquellas que restringen la pesca recreativa de especies pelagicas. Una pregunta importante es QQQ ?bajo que condiciones la pesca pelagica recreativa es compatible con los objetivos de conservacion de un AMP que se enfoca principalmente en comunidades bentonicas? En 2005, un taller de expertos en biologia pesquera, ecologfa marina, manejo de AMP y Pescadores recreativos fue convocado por el Centra Nacional de AMP de la NOAA para evaluar los pocos datos empiricos del acoplamiento entre los sistemas pelagico y bentonico, y ofrecer asesoria practica sobre el tema. Los participantes (i) propusieron un marco conceptual preliminar para abordar el tema de la zonacion vertical, (ii) desarrollar directrices preliminares para que cuando se haga una evaluation si se permite o restringe la pesca pelagica dentro de la AMP, y (iii) identificar futuras lineas de investigation para comprender mejor el acoplamiento entre el bentos y el sistema pelagico. Se identifico una serie de condiciones ecologicas en las que la pesca recreativa pelagica puede no ser compatible con la conservacion del bentos: (1) habitat de alto relieve, (2) profundidades menores a 50 m-100 m (dependiendo de la zona), (3) caracteristicas oceanograficas y topograficas sobresalientes, y (4) areas de desove. De igual forma, bajo varias circunstancias, la pesca pelagica puede no afectar las comunidades bentonicas. Hasta que los estudios cientificos brinden mas information acerca de como las relaciones entre el bentos y el ambiente pelagico afectan los objetivos especificos de la conservacion, el contexto propuesto en este trabajo provee una guia practica y de facil aplicacion para utilizar la zonacion vertical en el manejo pesquero en varios aspectos de las AMP que se enfocan en la conservacion del bentos.Keywords: Trophic level, Marine protected areas, Pelagic fisheries, Conservatio

Mapping reef fish and the seascape: using acoustics and spatial modeling to guide coastal management

Reef fish distributions are patchy in time and space with some coral reef habitats supporting higher densities (i.e., aggregations) of fish than others. Identifying and quantifying fish aggregations (particularly during spawning events) are often top priorities for coastal managers. However, the rapid mapping of these aggregations using conventional survey methods (e.g., non-technical SCUBA diving and remotely operated cameras) are limited by depth, visibility and time. Acoustic sensors (i.e., splitbeam and multibeam echosounders) are not constrained by these same limitations, and were used to concurrently map and quantify the location, density and size of reef fish along with seafloor structure in two, separate locations in the U.S. Virgin Islands. Reef fish aggregations were documented along the shelf edge, an ecologically important ecotone in the region. Fish were grouped into three classes according to body size, and relationships with the benthic seascape were modeled in one area using Boosted Regression Trees. These models were validated in a second area to test their predictive performance in locations where fish have not been mapped. Models predicting the density of large fish (≥29 cm) performed well (i.e., AUC = 0.77). Water depth and standard deviation of depth were the most influential predictors at two spatial scales (100 and 300 m). Models of small (≤11 cm) and medium (12–28 cm) fish performed poorly (i.e., AUC = 0.49 to 0.68) due to the high prevalence (45–79%) of smaller fish in both locations, and the unequal prevalence of smaller fish in the training and validation areas. Integrating acoustic sensors with spatial modeling offers a new and reliable approach to rapidly identify fish aggregations and to predict the density large fish in un-surveyed locations. This integrative approach will help coastal managers to prioritize sites, and focus their limited resources on areas that may be of higher conservation value

Form and function of tropical macroalgal reefs in the Anthropocene

1. Tropical reefs have been subjected to a range of anthropogenic pressures such as global climate change, overfishing and eutrophication that have raised questions about the prominence of macroalgae on tropical reefs, whether they pose a threat to biodiversity, and how they may influence the function of tropical marine ecosystems. 2. We synthesise current understanding of the structure and function of tropical macroalgal reefs, and how they may support various ecosystem goods and services. We then forecast how key stressors may alter the role of macroalgal reefs in tropical seascapes of the Anthropocene. 3. High levels of primary productivity from tropical canopy macroalgae, which rivals that of other key producers (e.g., corals, turf algae), can be widely dispersed across tropical seascapes to provide a boost of secondary productivity in a range of biomes that include coral reefs, and support periodic harvests of macroalgal biomass for industrial and agricultural uses. Complex macroalgal reefs that comprise a mixture of canopy and understory taxa can also provide key habitats for a diverse community of epifauna, as well as juvenile and adult fishes that are the basis for important tropical fisheries. 4. Key macroalgal taxa (e.g., Sargassum) that form complex macroalgal reefs are likely to be sensitive to future climate change. Increases in maximum sea temperature, in particular, could depress biomass production and/or drive phenological shifts in canopy formation that will affect their capacity to support tropical marine ecosystems. 5. Macroalgal reefs can support a suite of tropical marine ecosystem functions when embedded within an interconnected mosaic of habitat types. Habitat connectivity is, therefore, essential if we are to maintain tropical marine biodiversity alongside key ecosystem goods and services. Consequently, complex macroalgal reefs should be treated as a key ecological asset in strategies for the conservation and management of diverse tropical seascapes

Spatial Analyses of Benthic Habitats to Define Coral Reef Ecosystem Regions and Potential Biogeographic Boundaries along a Latitudinal Gradient

Marine organism diversity typically attenuates latitudinally from tropical to colder climate regimes. Since the distribution of many marine species relates to certain habitats and depth regimes, mapping data provide valuable information in the absence of detailed ecological data that can be used to identify and spatially quantify smaller scale (10 s km) coral reef ecosystem regions and potential physical biogeographic barriers. This study focused on the southeast Florida coast due to a recognized, but understudied, tropical to subtropical biogeographic gradient. GIS spatial analyses were conducted on recent, accurate, shallow-water (0–30 m) benthic habitat maps to identify and quantify specific regions along the coast that were statistically distinct in the number and amount of major benthic habitat types. Habitat type and width were measured for 209 evenly-spaced cross-shelf transects. Evaluation of groupings from a cluster analysis at 75% similarity yielded five distinct regions. The number of benthic habitats and their area, width, distance from shore, distance from each other, and LIDAR depths were calculated in GIS and examined to determine regional statistical differences. The number of benthic habitats decreased with increasing latitude from 9 in the south to 4 in the north and many of the habitat metrics statistically differed between regions. Three potential biogeographic barriers were found at the Boca, Hillsboro, and Biscayne boundaries, where specific shallow-water habitats were absent further north; Middle Reef, Inner Reef, and oceanic seagrass beds respectively. The Bahamas Fault Zone boundary was also noted where changes in coastal morphologies occurred that could relate to subtle ecological changes. The analyses defined regions on a smaller scale more appropriate to regional management decisions, hence strengthening marine conservation planning with an objective, scientific foundation for decision making. They provide a framework for similar regional analyses elsewhere

Evaluating Patterns of a White-Band Disease (WBD) Outbreak in Acropora palmata Using Spatial Analysis: A Comparison of Transect and Colony Clustering

. Likewise, there is little known about the spatiality of outbreaks. We examined the spatial patterns of WBD during a 2004 outbreak at Buck Island Reef National Monument in the US Virgin Islands. colonies with and without WBD.As the search for causation continues, surveillance and proper documentation of the spatial patterns may inform etiology, and at the same time assist reef managers in allocating resources to tracking the disease. Our results indicate that the spatial scale of data collected can drastically affect the calculation of prevalence and spatial distribution of WBD outbreaks. Specifically, we illustrate that higher resolution sampling resulted in more realistic disease estimates. This should assist in selecting appropriate sampling designs for future outbreak investigations. The spatial techniques used here can be used to facilitate other coral disease studies, as well as, improve reef conservation and management