Acoustic tracking of reef fishes to elucidate habitat utilization patterns and residence times inside and outside marine protected areas around the island of St. John, USVI

This technical memorandum describes a developing project under the direction of NOAA’s Biogeography Branch in consultation with the National Park Service and US Geological Survey to understand and quantify spatial patterns and habitat affinities of reef fishes in the US Virgin Islands. The purpose of this report is to describe and disseminate the initial results from the project and to share information on the location of acoustic receivers and species electronic tag ID codes. The Virgin Islands Coral Reef National Monument (VICRNM), adjacent to Virgin Islands National Park (VIIS), was established by Executive Order in 2000, but resources within the monument are poorly documented and the degree of connectivity to VIIS is unknown. Whereas, VICRNM was established with full protection from resource exploitation, VIIS has incurred resource harvest by fishers since 1956 as allowed in its enabling legislation. Large changes in local reef communities have occurred over the past several decades, in part due to overexploitation. In order to better understand the habitat utilization patterns and movement of fishes among management regimes and areas open to fishing around St, John, an array of hydroacoustic receivers was deployed while a variety of reef fish species were acoustically tagged. In July 2006, nine receivers with a detection range of ca. 350 m were deployed in Lameshur Bay on the south shore of St. John, within VIIS. Receivers were located adjacent to reefs and in seagrass beds, inshore and offshore of these reefs. It was found that lane snappers and bluestriped grunts showed diel movement from reef habitats during daytime hours to offshore seagrass bed at night. Timing of migrations was highly predictable and coincided with changes in sunrise and sunset over the course of the year. Fish associated with reefs that did not have adjacent seagrass beds made more extensive movements than those fishes associated with reefs that had adjacent seagrass habitats. In April 2007, 21 additional receivers were deployed along much of the south shore of St. John (ca. 20 km of shoreline). This current array will address broader-scale movement among management units and examine the potential benefits of the VICRNM to provide adult “spillover” into VIIS and adjacent harvested areas. The results from this work will aid in defining fine to moderate spatial scales of reef fish habitat affinities and in designing and evaluating marine protected areas.

Behavioral ontogeny in larvae and early juveniles of the giant trevally (Caranx ignobilis) (Pisces: Carangidae)

Behavior of young (8−18 mm SL) giant trevally (Caranx ignobilis), a large coral-reef−associated predator, was observed in the laboratory and the ocean. Size was a better predictor of swimming speed and endurance than was age. Critical speed increased with size from 12 to 40 cm/s at 2.7 cm/s for each mm increase in size. Mean scaled critical speed was 19 body lengths/s and was not size related. Swimming speed in the ocean was 4 to 20 cm/s (about half of critical speed) and varied among areas, but within each area, it increased at 2 cm/s for each mm increase in size. Swimming endurance in the laboratory increased from 5 to 40 km at 5 km for each mm increase in size. Vertical distribution changed ontogenetically: larvae swam shallower, but more variably, and then deeper with growth. Two-thirds of individuals swam directionally with no ontogenetic increase in orientation precision. Larvae swam offshore off open coasts, but not in a bay. In situ observations of C. ignobilis feeding, interacting with pelagic animals, and reacting to reefs are reported. Manusc

Corals, fishermen and tourists

Two major anthropogenic activities that disturb coral reefs are fishing and tourism, even though coral reefs are important for both fishing and tourism. Already more than 60 per cent of all reefs worldwide are endangered. The use of explosives and poison by small-scale fishers, to supply the market for live fish for aquariums and for human consumption, cause irreversible damages to reefs. Similarly, rapid and unmanaged coastal development for marine tourism negatively affects coral reefs in many ways. Though marine parks and marine protected areas are being promoted all over the world, developing countries need assistance in establishing and assessing such reserves and for taking appropriate actions for rehabilitation of reefs. These can be accomplished through partnership projects.

The coupling of St. John, US Virgin Islands Marine Protected Areas based on reef fish habitat affinities and movements across management boundaries [Poster]

NOAA's Biogeograpy Branch, the National Park Service (NPS), US Geological Survey, and the University of the Virgin Islands (UVI) are using acoustice telemetry to quantify spatial patterns and habitat affinities of reef fishes in the US Virgin Islands (USVI). The objective of the study is to define the movements of reef fishes among habitats within and between the Virgin Islands Coral Reef Nationla Monument (VICRNM), adjacent to Virgin Islands National Park (VIIS), and USVI Territorial waters. In order to better understand species habitat utilization patterns and movement of fishes among management regimes and areas open to fishing around St. John, we deployed an array of hydroacoutstic receivers and acoustically tagged reef fishes. A total of 150 fishes, representing 18 species and 10 families were acoustically tagged along the south shore of St. John from July 2006 to June 2008. Thirty six receivers with a detection range of approximately 300m each were deployed in shallow nearshore bays and across the shelf to depths of approximately 30m. Receivers were located within reefs and adjacent to reefs in seagrass, algal beds, or sand habitats. Example results include the movement of lane snappers and blue striped grunts that demonstrated diel movement from reef habitats during daytime hours to offshore seagrass beds at night. Fish associated with reefs that did not have adjacent seagrass beds made more extensive movements than those fishes associated with reefs that had adjacent seagrass habitats. The array comprised of both nearshore and cross shelf location of receives provides information on fine to broad scale fish movement patterns across habitats and among management units to examine the strength of ecological connectivity between management areas and habitats. For more information go to: http://ccma.nos.noaa.gov/ecosystems/ coralreef/acoustic_tracking.html

Estado de conservación de la ictiofauna arrecifal en sitios de buceo turístico de cuatro regiones del Archipiélago Sabana-Camagüey, Cuba.

Los peces constituyen uno de los atractivos principales en los arrecifes coralinos para el buceo turístico, por lo cual resulta necesario monitorear su abundancia y valores estéticos. El objetivo de esta investigación fue evaluar el estado de conservación de las asociaciones de peces arrecifales en cuatro de los principales polos turísticos del Archipiélago Sabana-Camagüey, Cuba en el año 2010. Se muestrearon 23 sitios de buceo turísticos en áreas adyacentes a las regiones de Varadero (5 sitios), cayos de Villa Clara (6 sitios), Cayo Coco (6 sitios) y Santa Lucia (6 sitios). En cada uno de ellos se realizaron seis réplicas de censos visuales de todas las especies de peces en recorridos lineales de 50 m de largo por 2 m de ancho, ocupando un área total de 600 m2. El puntaje más alto de conservación lo presentó los cayos de Villa Clara (37), siguiéndole en orden decreciente Cayo Coco (35), y con valores más bajos Varadero (24) y Santa Lucia (22). Los puntajes de las cuatro regiones fueron inferiores a los encontrados en otros arrecifes de Cuba y el Caribe. Los valores de Varadero y Santa Lucia se correspondieron con los de arrecifes de hábitats degradados y sometidos a explotación pesquera. En general, en la mayoría de las regiones predominaron peces de talla pequeña (<20 cm) pertenecientes a las familias Pomacentridae y Labridae y hubo poca abundancia de peces carnívoros y herbívoros de mediana (20-40 cm) y gran talla (>40 cm). ABSTRACT Fish are one of the main attractions on coral reefs for diving tourism; therefore, it is necessary to monitor their condition and aesthetic values. The objective of this research was to evaluate the status of reef fish assemblages in four tourist areas of Sabana-Camaguey Archipelago, Cuba in 2010. Twentythree tourist diving sites were sampled in adjacent areas to regions of Varadero (five sites), Villa Clara keys (6 sites), Coco key (6 sites) and Santa Lucia (6 sites). In each region, six replicated visual census of all fish species were conducted along belt transects of 50 m length and 2 m width, occupying a total area of 600 m2. The highest conservation score was obtained by Villa Clara keys (37), followed in decreasing order by Coco key (35), and with lower values Varadero (24) and St. Lucia (22). The scores of the four regions were lower than the values of other Cuban and Caribbean reefs. The values of Varadero and Santa Lucia corresponded to reefs with degraded habitats and subject to overfishing. In general, small fish (< 20 cm) from families Pomacentridae and Labridae, and low abundance of carnivore and herbivore fish of middle (20-40 cm) and large size (> 40 cm) predominated in most regions.

Proposal to permit experimental artificial reefs inside and outside the Big Sycamore Canyon Ecological Reserve

(Document pdf contains 19 pages)

Indicators for management of coral reefs and their applications to marine protected areas

Informed planning and decision-making in the management of natural resources requires an ability to integrate complex interactions in ecosystems and communicate these effectively to stakeholders. This involves coping with three fundamental dilemmas. The first comes from the irregular pulse of nature. The second is the recognition that there are no strictly objective criteria for judging the well-being of an ecosystem. The third is posed by the quest for indicators with some integrative properties that may be used to analyze an ecosystem and impart the information to the relevant resource users. This paper presents some examples of indicators used to: 1) assess the status of a coral reef and, in particular, the state of its fisheries resources; 2) identify reefs that are most threatened by human activities; and 3) evaluate the likelihood of success of management interventions. These indicators are not exhaustive, but illustrate the range of options available for the management of coral reef ecosystems.

Indicators for management of coral reefs and their applications to marine protected areas

Informed planning and decision-making in the management of natural resources requires an ability to integrate complex interactions in ecosystems and communicate these effectively to stakeholders. This involves coping with three fundamental dilemmas. The first comes from the irregular pulse of nature. The second is the recognition that there are no strictly objective criteria for judging the “well-being” of an ecosystem. The third is posed by the quest for indicators with some integrative properties that may be used to analyze an ecosystem and impart the information to the relevant resource users. This paper presents some examples of indicators used to: 1) assess the status of a coral reef and, in particular, the state of its fisheries resources; 2) identify reefs that are most threatened by human activities; and 3) evaluate the likelihood of success of management interventions. These indicators are not exhaustive, but illustrate the range of options available for the management of coral reef ecosystems.

The use of large artificial reefs to enhance fish populations at different depths in the Florida Keys

This study showed that large prefabricated units and concrete rubble patch reefs, placed as artificial marine habitats on sand bottom, greatly enhance the abundance, diversity, and biomass of fish in an area. Densities of individuals and biomass were found considerably higher at artificial reefs than at nearby, natural, bank reefs, a result consistent with other studies. Location, depth, and vertical profile are important factors determining fish assemblages at artificial habitats in the Keys. Fishes were both produced at artificial reefs and attracted from the surrounding area. Fish assemblages at the Hawk Channel artificial reefs were considerably different from those on the offshore reef tract, particularly in terms of dominant species. Rescue of the original 1992 work in 2005 was funded by the South Florida Ecosystem Restoration Prediction and Modeling Program.

Preliminary guide to the identification of the early life history stages of Gerreid fishes of the Western Central Atlantic

The family Gerreidae contains four genera and 13 species that occur in the western central North Atlantic. Adult gerreids are small to medium size fishes that are abundant in coastal waters, bays, and estuaries in tropical and warm temperate regions and sometimes occur in freshwaters. They are generally associate~ with grassy or open bottoms, but not with reefs. Gerreids are silvery fishes, with deeply forked tails, and extremely protrusible mouth that points downward when protracted. They apparently feed on bottom-dwelling organisms and at least one species (Eucinostomus gula) shows a distinct transition, during the juvenile period, from a planktivore (exclusively copepods) to a carnivore that includes a diet of almost solely polychaetes (Carr & Adams, 1973; Robins and Ray, 1987; Murdy et al., 1997). (PDF contains 10 pages)

Green Guide to the Cayman Islands 1: The marine environment

In the Cayman Islands we are enriched with a wonderful natural environment. In this Green Guide to our Marine Environment we hope to show you how all of our lives on these three magical islands are intimately connected to the land and the sea that surrounds it. Like many of our Caribbean neighbours, a large proportion of our economy depends on reef-based fishing, diving and tourism. The beauty of our coral reefs, our beaches and our lagoons is that it is part of our heritage, and it draws many thousands of overseas visitors to our shores. It is our responsibility, as stakeholders sharing this beautiful environment, to do what we can to minimise our impact upon it. Ogier has sponsored the Green Guide, and through this publication, is helping us to preserve our natural and cultural heritage.... [PDF contains 32 pages]

Green Guide to the Cayman Islands 2: Climate change and the sea around us

This Green Guide provides a brief summary of the alarming evidence of changing climate in the Cayman Islands. As we illustrated in our first Green Guide (2008), our lives on these three magical islands are intimately connected to the land and the surrounding sea. Our economy depends on keeping our islands healthy, because our coral reefs, our beaches, our natural heritage, all draw many thousands of overseas visitors to our shores. It is our responsibility, as stakeholders sharing this beautiful environment, to do what we can to minimise our impact upon it... [PDF contains 32 pages]

Aspects of the fishing industry and an overview of artificial reefs and fish aggregating devices for increasing fisheries output and viability in Nigeria

Aspects of the Nigerian fishing industry are outlined to explain the concept of fishing systems viability which is often influenced by a combination of factors including biological productivity, as well as technical, economic and social factors. The productivity of the aquatic environments can be increased by the construction and installation of artificial reefs and fish aggregating devices. These man-made structures provide shelters, food and breeding grounds for fin fish and shell fish. The habitat enhancement techniques are appropriate, efficient, cheap and simple strategic options for increase in fish production. Recommendations for effective utilization and long term management are outlined.

Physical circulation measurements in Pamlico Sound, used to locate new oyster sanctuaries

The population of eastern oyster, C. virginica, has declined over the last century on most areas of the east and gulf coasts. North Carolina’s restoration efforts depend on the construction of subtidal oyster reefs to be used as broodstock sanctuaries in Pamlico Sound, NC. Successful restoration of the oyster population requires several thriving reefs connected as a meta-population. C. virginica has a 2-3 week larval stage, during which it gradually settles through the water column. Larvae that can travel from one reef to another during that stage form the basis of a meta-population. (PDF contains 3 pages)