Statistical habitat models, such as generalized linear models (GLMs) and generalized additive models (GAMs), are key tools for assisting Ecosystem-based Fisheries Management (EBFM) efforts. These models can be used to map species distributions and assist in marine protected area (MPA) planning. In this study, the authors applied a statistical methodology to produce preference functions for fish and invertebrates along the West Florida Shelf, and then mapped the hotspots of juveniles and adults of three economically important species (Red Snapper, Gag, and Red Grouper) for informing future MPA planning. The analysis used a comprehensive survey database that included all encounter and nonencounter data of the study ecosystem collected by fisheries‐independent and fisheries‐dependent surveys. The REEF Volunteer Fish Survey Project dataset was one of 37 used in the analysis.
2018
Ciguatera fish poisoning is a global public health concern that is associated with Gambierdiscus, a genus of harmful algae found in coral reef environments that includes species known to produce toxins (ciguatoxins). It is thought that the pathway of Ciguatera toxins is through the food web, originating with herbivores that have fed on Gambierdiscus-associated macroalgae.
The objectives of this study were to define spatial and temporal patterns in reef health and Gambierdiscus abundance across patch reefs in the three regions of the Keys (Upper, Middle, Lower), to determine whether the drivers of those patterns were natural or anthropogenic, and to identify biogeographic indicators of risk. To address these objectives, this study combined field sampling with a “big data” approach to spatial analysis. REEF's dataset was included in one of the "big data" resources used. The study used population data from REEF's Volunteer Fish Survey Project database to estimate biomass of the herbivorous parrotfish and surgeonfishes. Preliminary findings of this work suggest that surgeonfish in the Florida Keys may be actively ingesting Gambierdiscus spp. cells, but more work is needed. Although this study did not find a direct linear relationship between anthropogenic factors and Gambierdiscus cell densities, there is evidence that human activities have an indirect influence on Ciguatera fish poisoning risk through reef health, as well as through overfishing, and the destruction of inshore habitats like seagrass and mangroves.
The lead author of this study has previously used the REEF Volunteer Fish Survey Project database to construct detailed food webs of coral reef ecosystems in several Caribbean locations, including Jamaica (see here). In this paper, the authors assess the reliability of historical reconstructions of biodiversity from the paleocommunity by simulating the fossilization of a highly threatened and disturbed modern ecosystem, a Caribbean coral reef. Using the high-resolution coral reef food web from Jamaica, the authors compared system structures of the modern and simulated fossil reefs, including guild richness and evenness, trophic level distribution, predator dietary breadth, food chain lengths, and modularity. The authors were able to use both the long history of Jamaican reef biodiversity records in museum collections and the published literature, combined with the extensive citizen scientist data collected by the REEF project. The REEF data were particularly important as they provided a current account of the composition of the reef biota. Results indicated that the overall guild diversity, structure, and modularity of the reef ecosystem remained intact. These results have important implications for the integrity of fossil food web studies and coral reef conservation, demonstrating that fossil reef communities can be used to understand reef community dynamics during past regimes of environmental change.
This paper describes cleaning behavior that had previously not been documented in a particular species. The findings are the result of the keen eyes of two active REEF surveyors – Carol Cox and Frank Krasovec. Carol frequently surveys in the northern Gulf of Mexico and Frank surveys in his home state of North Carolina. Both photographed Yellowprow Goby, Elacatinus xanthiprora, cleaning other fishes, which is not typical for the species. Scientist and frequent REEF advisor, Dr. Ben Victor, noticed the photos, and started working with Carol and Frank to more fully document and publish the findings. Frank co-authored the paper with Ben.
There are several species in the western Atlantic genus Elacatinus, and they are broadly separated in to two groups – cleaners and sponge-dwellers. In most of the region, several species of each group are present, and Yellowprow Goby are sponge gobies. But in the northern temperate limits, along the northeastern coast of the Gulf of Mexico and along the east coast of the USA at North Carolina (beyond the range of coral-reef development), the only Elacatinus present is the Yellowprow Goby. It appears that the lack of other local cleaner species has allowed the evolution of facultative cleaning behavior in a species from a group characterized by the absence of that behavior.
This is a great example of the power of citizen scientists, and highlights their role in continuing the tradition of field naturalist.
This paper is an inventory of fish and invertebrate monitoring programs in the US Gulf of Mexico, including the REEF Volunteer Fish Survey Project, which has been active in the region since 1994. The authors conducted a gap analysis of the programs, and provided recommendations for improving current monitoring programs and designing new programs, and guidance for more comprehensive use and sharing of monitoring data. They also compiled a large monitoring database encompassing much of the monitoring data collected in the region using random sampling schemes and employed this database to fit statistical models to then map the spatial distributions of 61 fish and invertebrate functional groups, species and life stages. The study included 73 monitoring programs in the region. This study was funded by the National Oceanic and Atmospheric Administration (NOAA) RESTORE Act Science Program.
2017
Culling can be an effective management tool for reducing populations of invasive species to levels that minimize ecological effects. However, culling is labour-intensive, costly, and may have unintended ecological consequences. In the Caribbean, culling is widely used to control invasive Indo-Pacific lionfish, Pterois volitans and P. miles, but the effectiveness of infrequent culling in terms of reducing lionfish abundance and halting native prey decline is unclear. In a 21-month-long field experiment on natural reefs, we found that culling effectiveness changed after the passage of a hurricane part-way through the experiment. Before the hurricane, infrequent culling resulted in substantial reductions in lionfish density (60–79%, on average, albeit with large uncertainty) and slight increases in native prey species richness, but was insufficient to stem the decline in native prey biomass. Culling every 3 months (i.e., quarterly) and every 6 months (i.e., biannually) had similar effects on lionfish density and native prey fishes because of high rates of lionfish colonization among reefs. After the hurricane, lionfish densities were greater on all culled reefs compared to non-culled reefs, and prey biomass declined by 92%, and species richness by 71%, on biannually culled reefs. The two culling frequencies we examined therefore seem to offer a poor trade-off between the demonstrated conservation gains that can be achieved with frequent culling and the economy of time and money realized by infrequent culling. Moreover, stochastic events such as hurricanes can drastically limit the effectiveness of culling efforts.
REEF Volunteer Fish Survey Project data were used in this publication to help elucidate annual mean abundance in Goliath Grouper at sites off the southeastern coast of Florida. The authors further used the data to look for probable spawning sites. The data showed the buildup of the Goliath Grouper population in the spawning area off SE Florida over time. However, there was insufficent survey effort to demonstrate a pattern off SW Florida. The visual REEF survey data were just one of several datasets and information used in this paper to evaluate the patterns of spawning in this endangered species.
The Grouper Moon Project is always looking for new and/or better ways of accurately estimating the number of spawning Nassau Grouper at the aggregation sites being monitored. In 2014, we tested the use of a split-beam echosounder as a tool for surveying the abundance and size of fish at the aggregation site; the results of the study are detailed in this peer-reviewed paper. We found that the echosounder performs fairly well at providing an index of abundance, although the absolute accuracy of the method was not sufficient to replace other survey methods (e.g. mark and recapture monitoring). After calibrating the method with diver-based fish length surveys, the tool was able to accurately capture estimates of aggregating fish sizes. Surveys on all 3 islands (Little Cayman, Cayman Brac, and Grand Cayman) showed that the average size of Nassau Grouper on Little Cayman was significantly larger than on both Brac and Grand. On the other hand, the sizes of Nassau Grouper on Brac and Grand were not significantly different. Based on this study, the echosounder is a potentially useful tool for surveying aggregations, but is likely best use to complement more intensive diver-based survey methods.
Lionfish derbies and tournaments were first implemented in 2009 with the intent of increasing public awareness about the lionfish invasion in the western Atlantic, gathering specimens for research, and training volunteers to safely and effectively collect the venomous species. Since then, REEF has coordinated a series of derbies each year and assisted other organizations and groups in organizing and running their own derbies, resulting in the removal of tens of thousands of invasive lionfish.
The increasing number of derbies held across the region presents an excellent opportunity to investigate the extent to which volunteer removal activities during such derbies can be an effective means of population suppression. Using REEF lionfish derbies as a test case, REEF staff, affiliated scientists, and volunteers worked together to address six key questions: 1) What is the total area over which removal can be affected during a derby event? 2) Is capture during derbies size-selective? 3) To what extent are local invader populations suppressed by derby activities? 4) At what rate do lionfish re-colonize following derby events? 5) Is removal sufficient to reduce and sustain densities below those predicted to cause predation-mediated declines in native species? and 6) Is the magnitude of invader removal related to catch per unit effort (CPUE)? To answer these questions, the authors collected data on landings and participant effort over three years of lionfish derbies in both Key Largo, Florida and Green Turtle Cay, Bahamas.
The study documented that from 2012-2014, single day derbies reduced lionfish densities by 52% across an area of 192 km2 on average each year. Differences in recolonization and productivity between regions meant that annual events were sufficient to suppress the invasion below levels predicted to cause declines in native species in one region, but not the other. Population reduction was not related to CPUE, confirming the importance of in situ monitoring to gauge control effectiveness. Future work to assess rates of recolonization in relation to derby frequency will help guide management and control decisions.
Estimating a population’s growth rate and year-to-year variance is a key component of population viability analysis (PVA). However, standard PVA methods require time series of counts obtained using consistent survey methods over many years. The authors of this study used REEF data along with two other fisheries datasets to evaluate the long-term trends of rockfish in Puget Sound, Washington State. The time-series analysis was performed with a multivariate autoregressive state-space (MARSS) model. The authors show that using a MARSS modeling approach can provide a rigorous statistical framework for solving some of the challenges associated with using multiple, sometimes inconsistent datasets, and can reduce the proportion of fisheries assessment cases that are assigned a designation of “data deficient.”
The analysis of the paper was part of the 5-year review of the Endangered Species Act (ESA) listing of Puget Sound populations of three rockfish species (Bocaccio, Canary Rockfish, and Yelloweye Rockfish), and was conducted by scientists at the National Marine Fisheries Service and Washington Department of Fish and Wildlife. The three sources of data included in the study were: (1) recreational catch data, (2) scuba surveys conducted by REEF surveyors, and (3) a fishery-independent trawl survey. Because there were too few observations of the three species of rockfish in the data sources to analyze these species directly, the MARSS analysis estimated the abundance of all rockfish. Because Bocaccio, Canary, and Yelloweye are deep water species, they are not often seen by REEF surveyors. The other two data sets showed that these rockfishes declined as a proportion of recreational catch between the 1970s and 2010s. The REEF data suggest that other species like Copper and Quillback rockfish have experienced population growth in shallower depths.