Recent concerns about changing elasmobranch populations have prompted the need to understand their patterns of distribution and abundance through non-destructive sampling methods. Since scientific divers represent a small portion of the total number of divers worldwide, the use of non-scientific divers could drastically increase the number of observations needed to monitor broad-scale, long-term trends. Here, we use 83,940 surveys collected by trained volunteer divers to examine spatial and temporal trends of the most frequently sighted elasmobranch species in the greater-Caribbean, the yellow stingray (Urobatis jamaicensis). Despite being relatively common and listed as Least Concern on the IUCN Red List, little is known about the status of this species. In total, yellow stingrays were observed on 5,658 surveys (6.7% sighting frequency) with the highest occurrence in the regions surrounding Cuba. Overall, sighting frequency declined from 20.5% in 1994 to 4.7% in 2007—a standardized decline rate of −0.11. However, these trends were not consistent in all regions. The strongest decline occurred in the Florida Keys, the most sampled region, where trends were similar among all areas, habitats and depths. In contrast, sighting frequency significantly increased in Jamaica where large fishes are severely depleted. We discuss possible explanations for these changes including habitat degradation, exploitation and changes in trophic interactions. Our results suggest large-scale changes in yellow stingray abundance that have been unnoticed by the scientific community. Thus, our study highlights the value of non-scientific divers for collecting data that can be used to understand population trends of otherwise poorly studied species.
2010
the mismatch between genetic and phenotypic divergence among deeply divided mtDNA lineages in a coral-reef goby, with the description of two new cryptic species from the Caribbean Sea
Long-time REEF supporters, Les and Keri Wilk of ReefNet, recently discovered and photographed a distinctively marked population of the Greenbanded Goby, Elacatinus multifasciatus, on the island of Utila, Honduras. The population was distinguished by a prominent red stripe across the cheek that is not found on other populations of Greenbanded Gobies, as well as more numerous green bars on the body. The Wilks contacted Dr. Ben Victor, a reef fish taxonomic expert, who conducted a regional genetic comparison of Greenbanded Gobies to evaluate hidden diversity within this colorful and cryptic reef fish. As part of the study, the REEF database was used to document the current geographic range of the species. Ben's results identified the unique looking fish to be a separate species that is now called the Redcheek Goby (E. rubrigenis). He also discovered that, based on genetic results, Greenbanded Goby along coastal Panama, despite looking just like others in the species, are most likely a distinct species that will now be called Panamanian Greenbanded Goby (E. panamensis)
2009
Understanding the current status of predatory fish communities, and the effects fishing has on them, is vitally important information for management. However, data are often insufficient at region-wide scales to assess the effects of extraction in coral reef ecosystems of developing nations. The author overcomes this difficulty by using REEF's large database from the Volunteer Survey Project, which is a publicly accessible, fisheries-independent database. The aim of the study was to provide a broad scale, comprehensive analysis of human impacts on predatory reef fish communities across the greater Caribbean region. Specifically, this study analyzed presence and diversity of predatory reef fishes over a gradient of human population density. Across the region, as human population density increases, presence of large-bodied fishes declines, and fish communities become dominated by a few smaller-bodied species. The analysis found a complete disappearance of several large-bodied fishes, which indicates ecological and local extinctions have occurred in some densely populated areas. These findings fill a fundamentally important gap in our knowledge of the ecosystem effects of artisanal fisheries in developing nations, and provide support for multiple approaches to data collection where they are commonly unavailable.
In this early paper, staff from REEF and NOAA studied feeding ecology of the invasive lionfish (Pterois volitans). The authors collected stomach content data from fishes taken throughout the Bahamian archipelago. Three relative metrics of prey quantity, including percent number, percent frequency, and percent volume, were used to compare three indices of dietary importance. Lionfish largely prey upon teleosts (78% volume) and crustaceans (14% volume). Twenty-one families and 41 species of teleosts were represented in the diet of lionfish; the top 10 families of dietary importance were Gobiidae, Labridae, Gram- matidae, Apogonidae, Pomacentridae, Serranidae, Blenniidae, Atherinidae, Mullidae, and Monacanthi- dae. The proportional importance of crustaceans in the diet was inversely related to size with the largest lionfish preying almost exclusively on teleosts. Lion- fish were found to be diurnal feeders with the highest predation occurring in the morning (08:00–11:00).
Predicting and mitigating the effects of invasive Indo-Pacific lionfish Pterois volitans on Caribbean fish communities requires a thorough understanding of the species’ predation behaviour in the invaded range, including the types and amounts of prey consumed and how foraging patterns vary in relation to extrinsic conditions. We studied the activity levels and prey consumption rates of lionfish on 12 shallow coral reefs in the Bahamas in relation to time of day and prey availability. Lionfish predation rates and activity levels were significantly higher during crepuscular (dawn and dusk) periods than at mid-day. Available prey fish biomass was highest at dawn but lower at mid-day and dusk, suggesting that lionfish predation activity is not limited by prey availability alone. Our calculated average daily mass-specific prey consumption rates, which incorporated daily variation, was ~3 times the estimates obtained from studies of captive lionfish in their native range and of invasive lionfish observed only during the day. Our results will help to predict more accurately the effect of predation by invasive lionfish on native reef fish communities.
This paper examined the genetic source of the invasive Indo-Pacific lionfish in the Bahamas. Many of the samples used in this study were collected during REEF's lionfish research trips during 2007 and 2008. Two species, Pterois volitans and P. miles, were well established along the United States east coast before the first lionfish were reported from the Bahamas in 2004, where they quickly dispersed throughout the archipelago by 2007. The source of the Bahamian lionfish invasion has been in question because of the hypothesized low connectivity between Florida and Bahamas reef species as well as the temporal lag in their arrival in the Bahamas. The results showed no significant differentiation between the Bahamas and North Carolina specimens. Sequence analyses also revealed the presence of only Pterois volitans in the Bahamas, with no P. miles detected in any of the specimens. These results indicate that the source of the Bahamian lionfish is egg and larval dispersal from the United States east coast population, and support previous models of reef fish dispersal that suggest a low level of connectivity between the Bahamas and east coast of Florida.
This report summarizes several years of work on Goliath Grouper to provide an understanding of adult ecology and behavior so that the population could be managed sustainably. REEF data were used to provide information on distribution patterns throughout the southeatern US and regional densities in Florida. The authors found high concordance between their quantitative reef survey data and the categorical abundance data collected by REEF volunteers, thus reducing uncertainty about use of REEF's population data for future stock assessments.
This was a predecision document prepared by NOAA’s Fisheries Service to evaluate the population status of five species of rockfish in the Puget Sound. REEF data were one of several datasets that were used by the fisheries scientists to make the evaluation. Based on the analyses, NOAA Fisheries proposed to list three populations of rockfish in Puget Sound and the Strait of Georgia for protection under the Endangered Species Act. The Georgia Basin populations of two of the rockfish species – canary and yelloweye – are proposed for “threatened” status. A third rockfish species – bocaccio – is proposed as “endangered.” Populations of all three rockfish species in the Georgia Basin, which encompasses Puget Sound and the Strait of Georgia, have been harvested at high levels, depleting their numbers. Rockfish, which are bottom dwellers, typically live long lives, and mature and reproduce slowly, making them especially vulnerable to overfishing. A final decision on the three will be made in the Spring 2010.
2008
This paper is the result of a workshop held at University of Washington in 2008 on nearshore rocky reefs. REEF Director of Science, Dr. Christy Pattengill-Semmens, presented data collected by REEF surveyors in the Pacific Northwest, and some details from that talk are in this paper. Nearshore temperate reefs are highly diverse and productive habitats that provide structure and shelter for a wide variety of fishes and invertebrates. Recreational and commercial fisheries depend on nearshore reefs, which also provide opportunities for non-extractive recreational activities such as diving. Many inhabitants of nearshore temperate reefs on the west coast of North America have very limited home ranges as adults, and recent genetic evidence indicates that the dispersion of the larval stages is often restricted to tens of kilometers. Management of temperate reef resources must be organized on very small spatial scales in order to be effective, offering unique technical challenges in terms of assessment and monitoring. New enabling legislation could assist in specifying mandates and adjusting institutional design to allow stakeholders and concerned citizens to formulate management policies at local levels, and to aid in implementing and enforcing these policies.
2007
This publication describes a new (to science) species of coral reef wrasse found by REEF surveyors at the Flower Garden Banks National Marine Sanctuary (FGBNMS). This species was nicknamed the "Mardi Gras wrasse" by sanctuary staff due to the bright purple, yellow and green coloration of the terminal male phase. The fish was originally discovered at the East Flower Garden Bank by members of a REEF survey team in 1997, and has been periodically observed (primarily at Stetson Bank) since that time. Subsequent investigation by Doug Weaver and sanctuary staff confirmed that it was in fact a previously undescribed species of wrasse. The scientific name of the species is Halichoeres burekae, in honor of FGBNMS photographers Frank and Joyce Burek, who obtained the first photograph of the fish. The Mardi Gras wrasse has also since been reported from the Veracruz region of Mexico.