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.
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 presents reconstructions of coral reef food webs in three Greater Antillean regions of the Caribbean: the Cayman Islands, Cuba, and Jamaica. The REEF Volunteer Fish Survey Project dataset is one of several used to construct the food webs. The datasets presented in this publication will facilitate comparisons of historical and regional variation, the assessment of impacts of species loss and invasion, and the application of food webs to ecosystem analyses (e.g. Coral Reefs in Crisis: The Reliability of Deep-Time Food Web Reconstructions as Analogs for the Present, 2018, PD Roopnarine and AA Dineen)
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.
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.
In response to conservation concerns for inshore rockfish, Fisheries and Oceans Canada implemented a system of 164 rockfish conservation areas (RCAs) in British Columbia as part of the Rockfish Conservation Strategy. RCAs were established between 2004 and 2007. RCAs are not marine protected areas (MPAs) because they were not designated though any MPA legislative tool such as Canada’s Ocean Act, but rather through a fishery closure using the Fisheries Act. They can, however, be considered harvest refugia. Evaluations of the performance of RCAs have recently been undertaken by government agencies, academics, non- governmental organizations (NGOs) and First Nations. This report describes the most recent scientific research on RCAs. Research has been done using remotely operated vehicles (ROVs), scuba surveys, hook-and-line fishing surveys, genetic analysis and compliance monitoring. Although some empirical research shows some RCAs are demonstrating an effect, most have not shown statistical differences in rockfish density among RCAs and non-RCA sites. One reason for this might be that RCAs are still considered to be “new” or “young” and it is thought that rockfish will take numerous years to respond to protection. REEF survey data for inshore rockfish and greenling species from Whytecliff Park between 1998 and 2013 were included in this report. Whytecliff Park is in West Vancouver, and was made the West Vancouver RCA in 2006.
This paper is part of the larger body of genetic research being conducted on Nassau Grouper in the Caribbean. The authors identified ten polymorphic microsatellite loci for Nassau grouper (Epinephelus striatus) by cross-amplification of loci isolated in Gulf coney (Epinephelus acanthistius). Samples from three geographic localities were scored for these loci –Glovers Reef off Belize (n = 50), Little Cayman (n = 50) and Grammanik Bank in the U.S. Virgin Islands (n = 50). Screening samples yielded 8 to 27 alleles per locus with observed levels of heterozygosity ranging from 0.30 to 0.96. Markers will be used in a Caribbean-wide study of Nassau grouper to understand patterns of genetic connectivity, as well as to contribute to fisheries management and conservation.
This paper presents a key technique that scientists from REEF and our Grouper Moon collaborators have used to monitor fish on the Little Cayman spawning aggregation that does not require the capture and handling of fish. We show that length-distribution data can be collected by divers using a video-based system with parallel lasers calibrated to a specific distance apart, and subsequently use those data to monitor changes in the size distribution over time.