Scientific Papers and Reports

Hamlets are a group of colourful coral reef fish found throughout the Caribbean. Ten species of hamlet have been discovered and each can be easily recognized by its own distinct colour pattern. In some areas, as many as seven varieties can be found on a single reef. However, most hamlet species are only found at specific locations. The blue hamlet, for example, is found only in the Florida region. How these very different looking, yet very closely related species came to be has been a a subject of debate among scientists. Data collected by divers and snorkelers as part of the REEF Volunteer Fish Survey Project were used in a large analysis to better understand the patterns of evolution in these and other marine fishes. They found that even widespread hamlet species are not found everywhere, and identified high density hotspots for each species. Because different species hotspots overlap and many species have more than one hotspot, the results do not support the theory that hamlets originated independently when they were geographically separated in the past. The research also showed how ecological factors, such as competition for food or habitat, may influence how different hamlet species co-exist.

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)

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.

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.

This is 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.

This paper describes two new species of goby that were discovered by REEF surveyors during a special training project in the Veracruz Marine Park in Mexico in 2003. Individuals of the two mystery gobies were photographed by REEF's Lad Akins. In cooperation with the marine park, specimens were collected and subsequently described as new species by Dr. Mike Taylor. The new finds include a neon-type goby that hovers in shoals above coral heads (Jarocho Goby, Elacatinus jarocho) and a tiger-striped goby that rests on rocks and coral (Cinta Goby, Elacatinus redimiculus). Both species are currently only known from reefs in southwestern Gulf of Mexico.

REEF data were used to provide a fisheries independant index for use in the mutton snapper stock assessment conducted by the South Atlantic and Gulf of Mexico Fisheries Management Councils as part of the SEDAR process. Three indices were calculated with different subsets of the REEF dive surveys: an index based on all dives on Florida’s Atlantic coast; an index based on sites that were visited by divers on at least seven of the 13 years, i.e. more than half, and at which mutton snapper were observed more than once; an index that used a logistic regression of presence or absence of species on the dives to calculate the probability that a dive would observe mutton snapper.

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.

This study analyzed temporal trends of the yellow stingray in the Florida Keys National Marine Sanctuary (FKNMS) as recorded by trained volunteer divers using the Roving Diver Technique. Data were obtained from the REEF Fish Survey Project. A generalized linear model on presence-absence data was used to estimate the change in yellow stingray by year. Habitat type, bottom time, depth, site, water temperature, and Julian date were included in the model to standardize the data. The decline in sighting frequency has occurred in all habitat types, depths, sites, and regions of the FKNMS. Within the FKNMS yellow stingray sightings declined from 32% SF (425 sightings in 1323 surveys) in 1994 to 8.5% SF (93 sightings in 1095 surveys) in 2005, averaging ~18% decline per year. The decline has gone virtually unnoticed. This study highlights the importance of protecting marine communities for the preservation of fishery resources and shows the importance of recording all marine species extractions. It also demonstrates the value and application of trained volunteer divers for monitoring temporal trends and species interactions of marine communities. This work was presented at the Summer 2006 American Elasmobranch Society meeting in New Orleans.

This paper summarized the first five years of monitoring of the Little Cayman West End aggregation, including a summary of spawning activity, total numbers of fish present at the aggregation each year, coloration, and behavior.