This is an annotated list of the published papers and reports that have included REEF data. The list is in chronological order. Papers that are available for viewing in .pdf format are noted.
Also see the Projects page for links to additional reports.
The study, conducted by Dr. Stephanie Green (OSU/REEF), Lad Akins (REEF), and others, confirms for the first time that controlling lionfish populations in the western Atlantic Ocean can pave the way for a recovery of native fish. Even if it's one speared fish at a time, data are showing that removals can be effective. And not every lionfish need be removed…the research findings document that reducing lionfish numbers by specified amounts will allow a rapid recovery of native fish biomass. Over 18 months, the biomass of native prey fishes increased an average 50-70% on reefs where lionfish numbers were suppressed below target levels predicted to cause prey depletion. On reefs where lionfish numbers remained higher than target levels, the biomass of prey fishes decreased by a further 50%. While complete eradication of lionfish from the Caribbean is not likely, groups are actively removing them from coastal areas (mostly via spear and net). This study is a first step in showing that strategic local efforts that suppress the invasion to low levels can help protect and recover native fish communities affected by lionfish. This ground-breaking invasive lionfish research was conducted as a collaboration between REEF, Oregon State University, Simon Fraser University, and the Cape Eleuthera Institute.
Invasive lionfish in the western Atlantic are known to be voracious predators. Their unusual hunting behavior suggests that they could prey on most fish species within their gape size limits. Significant research by REEF researchers and others has been conducted looking at stomach contents of lionfish to identify prey. However, relatively few prey species have been identified because of the challenge of identifying partly digested prey. It is also difficult to know how well the identifiable diet reflects the unidentified portion. The authors of this study addressed this issue by DNA-barcoding unidentifiable fish items from the stomachs of 130 lionfish. They identified 37 prey species, half of which had previously not been recorded. The visually identifiable species only accounted for 25% of the total prey items, making it clear that extrapolating total prey from the identifiable portion is not accurate. The barcoding technique used can increase the ability to predict the impacts of invasive predators on recipient communities.
Research conducted by Dr. Ben Holt from University of East Angila in the UK shows that methods to record marine diversity used by REEF surveyors returned results consistent with techniques favoured by peer-reviewed science. The findings give weight to the growing phenomenon of citizen science programs such as REEF's Volunteer Survey Project. The field study compared methods used by REEF volunteer SCUBA divers with those used by professional scientists to measure the variety of fish species in three Caribbean sites in the Turks and Caicos. The divers surveyed the sites using two methods – the 'belt transect', used in peer reviewed fish diversity studies, and the 'roving diver technique', used by REEF volunteers. Two teams of 12 divers made 144 separate underwater surveys across the sites over four weeks. While the traditional scientific survey revealed sightings of 106 different types of fish, the volunteer technique detected greater marine diversity with a total of 137 in the same waters. Dr Holt led the research in partnership with the Centre for Marine Resource Studies in the Caribbean and the University of Copenhagen, Denmark. He said: "The results of this study are important for the future of citizen science and the use of data collected by these programs. Allowing volunteers to use flexible and less standardised methods has important consequences for the long term success of citizen science programs. Amateur enthusiasts typically do not have the resources or training to use professional methodology. Our study demonstrates the quality of data collected using a volunteer method can match, and in some respects exceed, protocols used by professional scientists."
This paper describes several models to convert order-of-magnitude count data that are collected during REEF Roving Diver Technique (RDT) surveys to a numeric mean, and demonstrate that with a sufficient number of surveys, estimates of the mean with a reasonably small confidence interval can be attained. For each model, parameter estimates and associated confidence intervals were derived from 292 RDT surveys where precise counts were also made. Models were compared using the small sample Akaike Information Criteria (AICc). The best-fitting model uses disaggregated bin-count data and considers the relative proportion of counts in adjacent bins. A companion paper was published in the same CalCOFI issue that uses the model to evaluate population trends in rocky reef fish species along the Monterey Peninsula region in central California.
A database of fish surveys conducted by volunteer recreational divers trained by REEF was used to examine fish populations in Monterey Peninsula, California, between 1997 and 2011. Over 3,000 surveys were conducted as part of this ongoing citizen science effort. The analysis was conducted using a numerical conversion method to calculate population estimates from REEF log-scale data (this method was described in a companion paper published in the same CalCOFI Reports issue). Variations in relative density over time are reported for 18 fish species, including several fisheries-targeted species. Two recruitment pulses of young-of-the-year rockfish (Sebastes spp.) were observed over the study period, with subsequent increases in older rockfish. Several predator species increased and subsequently declined, peaking two years after prey populations. Strong concordance was found between REEF data and those collected by Partnership for Interdisciplinary Studies of Coastal Oceans (PISCO), a consortium of academic institutions. Results show that data collected by REEF has great potential to augment and strengthen professional research data and serve as a valuable baseline to evaluate marine reserves.
Despite being the world’s largest rays and providing significant revenue through dive tourism, little is known about the population status, exploitation, and trade volume of the Mobulidae (mobulids; Manta and Mobula spp.). There is anecdotal evidence, however, that mobulid populations are declining, largely due to the recent emergence of a widespread trade for their gill rakers. Researchers from Dalhousie University and eShark.org used expert divers’ observations from two citizen science programs, REEF's Volunteer Fish Survey Project and eShark.org, to describe global manta and devil ray abundance trends and human use patterns. The study highlights the relative rarity of aggregation sites on a global scale and reveals that many populations appear to be declining. The authors warn that newly emerging fisheries for the rays gill-‐rakers likely exceed their ability to recover. The study also demonstrates the deficiency of official catch reports, as only four countries have ever reported landing manta or devil rays– Indonesia, Liberia, Spain and Ecuador. However, numerous diver reports compiled in the paper illustrate that many other countries are regularly landing and selling these rays without reporting.
The authors describe the behavioral interactions of piscivorous mid-water and demersal fishes at subtropical live-bottom reefs off the coast of Georgia and off the west coast of Florida in the northeast Gulf of Mexico. The observations are used to construct a topological behavior web of the interactions of mid-water and demersal piscivores, their prey, and those associated species that modify predator-prey interactions. Results show that inter-specific behavioral interactions are common attributes of piscivores in these reef fish communities. The authors propose a framework for assessing the demographic consequences of such interactions. Data for this study were collected using a modified Roving Diver Technique, the method employed by REEF surveyors. One of the co-authors, Dave Grenda, is a member of REEF's Advanced Assessment Team.
There is an increasing need to examine regional patterns of diversity in coral-reef systems because their biodiversity is declining globally. The authors used REEF data from 80 sites from 6 eco-regions throughout the Caribbean to evaluate patterns of biodiversity. Specifically, they used "additive partitioning", which quantifies the contribution of different types of diversity (alpha and beta; comparing diversity between sites within a region and between regions) to total diversity across different spatial scales. The primary objective was to identify patterns of reef-fish diversity across multiple spatial scales under different scenarios, examining factors such as fisheries and demographic connectivity. Total diversity at the Caribbean scale was attributed to β-diversity (nearly 62% of the species), with the highest β-diversity at the site scale. α⎯⎯-diversity was higher than expected by chance in all scenarios and at all studied scales.
This suggests that fish assemblages are more homogenous than expected, particularly at the ecoregion scale. Within each ecoregion, diversity was mainly attributed to alpha, except for the Southern ecoregion where there was a greater difference in species among sites. β-components were lower than expected in all ecoregions, indicating that fishes within each ecoregion are a subsample of the same species pool. The scenario involving the effects of fisheries showed a shift in dominance for β-diversity from regions to subregions, with no major changes to the diversity patterns. In contrast, demographic connectivity partially explained the diversity pattern. β-components were low within connectivity regions and higher than expected by chance when comparing between them. The author's results highlight the importance of ecoregions as a spatial scale to conserve local and regional coral reef-fish diversity.
Over the past decade, Indo-Pacific lionfishes have invaded and spread throughout much of the tropical and subtropical northwestern Atlantic Ocean and Caribbean Sea. These species are generalist predators of fishes and invertebrates with the potential to disrupt the ecology of the invaded range. Lionfishes have been present in low numbers along the east coast of Florida since the 1980s, but were not reported in the Florida Keys until 2009. This paper uses data from the 20,000+ REEF surveys conducted in Florida since the early 1990s, along with other long-term data sources, to document the appearance and rapid spread of lionfishes in the Florida Keys. The results are the first to quantify the invasion of lionfishes in a new area using multiple independent, ongoing monitoring data sets, two of which have explicit estimates of sampling effort. Between 2009 and 2011, lionfish frequency of occurrence, abundance, and biomass increased rapidly, increasing three- to six-fold between 2010 and 2011 alone. In addition, individuals were detected on a variety of reef and non-reef habitats throughout the Florida Keys. Because lionfish occurrence, abundance, and impacts are expected to continue to increase throughout the region, monitoring programs like REEF's Volunteer Survey Project will be essential to document ecosystem changes that may result from this invasion.
Members of REEF's Grouper Moon Project team, including researchers from Oregon State University, have been conducting annual monitoring of the size and color phase of individual Nassau grouper found at the spawning aggregation on Little Cayman in the Cayman Islands. During non-spawning periods Nassau grouper display a reddish-brown-and-white barred coloration. However, while aggregating they exhibit three additional color phases: “bicolor”, “dark”, and “white belly”. Each year, Grouper Moon Project researchers and volunteers use a video camera with lasers mounted on the camera housing. The divers focus the laser caliper equipped video camera on individual fish at the aggregation, capturing several seconds of footage for each fish. We later analyze the video to determine the length of the fish and record the color phase. This paper summarizes five years of video data. Our observations show that the relative proportion of fish in the bicolor color phase increases significantly on the day leading up to the primary night of spawning. The increase in the proportion of the bicolor color phase from 0.05 early in the aggregation to 0.40 on the day of spawning suggests that this color phase conveys that a fish is behaviorally and physiologically prepared to spawn. Additionally, 82.7% of fish exhibiting dark or white belly coloration early in the aggregation period suggests that these color phases are not only shown by female fish as was previously assumed in the scientific literature. This is just one aspect of the important marine conservation research being conducted as part of the Grouper Moon Project. To find out more, visit the Grouper Moon Project webpage.