Recreational anglers' valuation of near-shore marine fisheries in Florida

This report describes and summarizes the results from a state-wide survey of Florida resident saltwater anglers. The survey was designed to provide estimates of the economic value anglers place on marginal changes in management of selected near-shore marine species. The Contingent valuation method was used to elicit angler willingness to pay for changes in management for redfish, seatrout , mullet, sheepshead, pompano. and king mackerel. Contingent valuation is a process in which respondents are presented with a detailed scenario that describes an opportunity to express their willingness to pay for a proposed change in current conditions. The process consists of three parts. First. the change in current conditions, or the "good" to be valued is described. Second, the payment method is described. The payment method is usually closely related to typical methods of buying goods similar to the one to be valued. Finally. the respondent is asked how much they would pay for the good described in the scenario. A special saltwater fishing license stamp that would allow the holder to take advantage of the described management change was used as a payment mechanism. (PDF contains 147 pages.)

An annotated bibliography on the biology and fishery of the skipjack tuna, Katsuwonis pelamis, of the Pacific Ocean

ENGLISH: The skipjack tuna, Katsuwonus pelamis is an important resource of the tropical and subtropical waters of the world ocean. Fishermen of many countries exploit this resource; at the present time, the annual world catch is approximately 200 thousand metric tons. Many fishery experts believe that the skipjack is not being fully utilized while stocks of other tunas are being fished, in some areas, at levels exceeding their maximum sustainable yields. In addition to the importance of skipjack as a commercial fish and as a source of food, there is a small but expanding recreational fishery in some countries bordering the Pacific. This bibliography provides a list of publications pertaining to the biology and fishery of the Pacific skipjack tuna. Papers concerned with food technology, food chemistry, radio-chemistry, and certain other subjects are excluded. The main sources for our publication have been the existing bibliographies of tunas, which are listed and indexed accordingly. In addition, reports of various marine laboratories and other scientific organizations have been checked; these are too numerous to list. We are fairly confident that all major works pertaining to skipjack tuna in the Pacific, printed prior to the end of 1966, appear in this bibliography. Only reports considered to be in permanent form are included. Annotations are based on actual examination of each of the entries listed here. The annotations do not evaluate a paper but serve rather to give a more precise idea of its contents if not revealed by the title alone. If the title sufficed in this respect, no annotation was prepared. A relatively small number of works believed to contain information pertinent to our bibliography could not be examined, but a list of such papers is provided. SPANISH: El atún barrilete, Katsuwonus pelamis, es un recurso importante de las aguas tropicales y subtropicales del océano mundial. Los pescadores de varios países explotan este recurso; actualmente, la captura mundial anual es aproximadamente de 200,000 toneladas métricas. Muchos expertos en la pesquería creen que el barrilete no es utilizado completamente, mientras los stocks de otros atunes son pescados en algunas áreas a niveles que exceden su rendimiento máximo sostenible. Además de la importancia del barrilete como pez comercial y como fuente de alimento, existe una pesquería pequeña recreativa que se está desarrollando en algunos países colindantes con el Pacífico. Esta bibliografía suministra una lista de publicaciones correspondientes a la biología y pesquería del atún barrilete en el Pacífico. Estudios referentes a la tecnología alimenticia, química alimenticia, radioquímica y ciertos otros sujetos son excluídos. Las fuentes principales correspondientes a nuestra publicación han sido las bibliografías existentes sobre atunes, las cuales están enumeradas y catalogadas de acuerdo. Además, se han examinado los informes de varios laboratorios marítimos y los de otras organizaciones científicas; éstos son demasiado numerosos para enumerar. Estamos bastante seguros de que todos los trabajos principales correspondientes al atún barrilete del Pacífico, editados antes de terminar el año de 1966, aparecen en esta bibliografía. Se incluyen únicamente los informes que se consideran permanentes. Las anotaciones se basan en el examen actual de cada una de las entradas aquí referidas. Las anotaciones no evaluan un estudio, pero sirven más bien para dar una idea más precisa de su contenido si el título por sí mismo no lo explica. No se preparó ninguna anotación si el título a este respecto era suficiente. Un número relativamente pequeño de trabajos que se cree tengan información pertinente a nuestra bibliografía no pudo ser examinado, pero se suministra una lista de tales estudios. (PDF contains 227 pages.)

Economics of co-managing water quality and invasive species for California and Baja California coastal boats

Regulatory action to protect California’s coastal water quality from degradation by copper from recreational boats’ antifouling paints interacts with efforts to prevent transport of invasive, hull-fouling species. A copper regulatory program is in place for a major yacht basin in northern San Diego Bay and in process for other major, California boat basins. “Companion” fouling control strategies are used with copper-based antifouling paints, as some invasive species have developed resistance to the copper biocide. Such strategies are critical for boats with less toxic or nontoxic hull coatings. Boat traffic along over 3,000 miles of coastline in California and Baja California increases invasive species transport risks. For example, 80% of boats in Baja California marinas are from the United States, especially California. Policy makers, boating businesses and boat owners need information on costs and supply-side capacity for effective fouling control measures to co-manage water quality and invasive species concerns. (PDF contains 3 pages)

Long Bay hypoxia study: A collaborative and multidisciplinary approach

The nearshore waters along the Myrtle Beach area are oceanographically referred to as Long Bay. Long Bay is the last in a series of semi-circular indentations located along the South Atlantic seaboard. The Bay extends for approximately 150 km from the Cape Fear River in North Carolina to Winyah Bay in South Carolina and has a number of small inlets (Figure 1). This region of the S.C. coast, commonly referred to as the “Grand Strand,” has a significant tourism base that accounts for a substantial portion of the South Carolina economy (i.e., 40% of the state’s total in 2002) (TIAA 2003). In 2004, the Grand Strand had an estimated 13.2 million visitors of which 90% went to the beach (MBCC 2006). In addition, Long Bay supports a shore-based hook and line fishery comprised of anglers fishing from recreational fishing piers, the beach, and small recreational boats just offshore. (PDF contains 4 pages)

Alleviating poverty and enhancing food security through fish production in man-made lakes

Man-made lakes inhabit diverse species of which the fish fauna constitutes the most targeted species of exploitation. For man-made lakes to serve as means of alleviating poverty an enhancing food security through increased fish production in Nigeria, sound management of the lake is strongly recommended. It will include the maintenance of good water quality, stocking with good species, control of over fishing, conservation of extinction and declining species as well as adequate legislation to regulate fishing activities. Recreational and tourism facilities can also be incorporated along with fish production in these man-made lakes to provide additional income and revenue for individual and Government. Some other practical ways by which these water bodies can be improved for effective and sustainable fish production as well as alleviating poverty was discussed

Herpetofaunal Inventories of the National Parks of South Florida and the Caribbean: Volume III. Big Cypress National Preserve

Amphibian declines and extinctions have been documented around the world, often in protected natural areas. Concern for this trend has prompted the U.S. Geological Survey and the National Park Service to document all species of amphibians that occur within U.S. National Parks and to search for any signs that amphibians may be declining. This study, an inventory of amphibian species in Big Cypress National Preserve, was conducted from 2002 to 2003. The goals of the project were to create a georeferenced inventory of amphibian species, use new analytical techniques to estimate proportion of sites occupied by each species, look for any signs of amphibian decline (missing species, disease, die-offs, and so forth.), and to establish a protocol that could be used for future monitoring efforts. Several sampling methods were used to accomplish these goals. Visual encounter surveys and anuran vocalization surveys were conducted in all habitats throughout the park to estimate the proportion of sites or proportion of area occupied (PAO) by each amphibian species in each habitat. Opportunistic collections, as well as limited drift fence data, were used to augment the visual encounter methods for highly aquatic or cryptic species. A total of 545 visits to 104 sites were conducted for standard sampling alone, and 2,358 individual amphibians and 374 reptiles were encountered. Data analysis was conducted in program PRESENCE to provide PAO estimates for each of the anuran species. All of the amphibian species historically found in Big Cypress National Preserve were detected during this project. At least one individual of each of the four salamander species was captured during sampling. Each of the anuran species in the preserve was adequately sampled using standard herpetological sampling methods, and PAO estimates were produced for each species of anuran by habitat. This information serves as an indicator of habitat associations of the species and relative abundance of sites occupied, but it will also be useful as a comparative baseline for future monitoring efforts. In addition to sampling for amphibians, all encounters with reptiles were documented. The sampling methods used for detecting amphibians are also appropriate for many reptile species. These reptile locations are included in this report, but the number of reptile observations was not sufficient to estimate PAO for reptile species. We encountered 35 of the 46 species of reptiles believed to be present in Big Cypress National Preserve during this study, and evidence exists of the presence of four other reptile species in the Preserve. This study found no evidence of amphibian decline in Big Cypress National Preserve. Although no evidence of decline was observed, several threats to amphibians were identified. Introduced species, especially the Cuban treefrog (Osteopilus septentrionalis), are predators and competitors with several native frog species. The recreational use of off-road vehicles has the potential to affect some amphibian populations, and a study on those potential impacts is currently underway. Also, interference by humans with the natural hydrologic cycle of south Florida has the potential to alter the amphibian community. Continued monitoring of the amphibian species in Big Cypress National Preserve is recommended. The methods used in this study were adequate to produce reliable estimates of the proportion of sites occupied by most anuran species, and are a cost-effective means of determining the status of their populations.

Natural habitat and population control mechanism of Crassula helmsii (Australian Swamp Stonecrop) in Australia

The plant Crassula helmsii (Kirk) Cochayne, was likely to become widely distributed and to dominate many damp and wet areas of nature reserves, recreational waters and agricultural drainage of Britain. The aim of this report was to study Australian Swamp Stonecrop in its natural habitat where it is in balance with its environment. This contrasts with its rapid and widespread distribution in the U.K. where its growth interferes with the use of fisheries and amenity lakes but also reduces the value of nature reserves and sites of special scientific interest by suppressing native flora. It was proposed to observe its growth at a variety of sites over its natural distribution and to include some environmental factors, e.g. water-level, water-chemistry (nutrients, acidity and alkalinity), frost-tolerance, salinity, with the help of portable sensors, locally-available services or data. 8 weeks of travel in Australia allowed time to study the plant in its natural habitat including the coastal areas of the southern half of the continent i.e . Western Australia, South Australia, New South Wales, Victoria, Tasmania and southern Queensland. The overall objective was to determine the environmental range by visits to selected sites of Crassula helmsii over its geographic range.

Turbidity and plant growth in large slow-flowing lowland rivers. Progress Report: March 1989

The River Great Ouse is a highly managed large lowland river in eastern England. It drains rich arable land in the Midlands and Eastern England and over the years nutrient concentrations have increased and there is a general perception that the clarity of the water has decreased. The main river channels have been dredged a number of times partly for flood control reasons but also for recreational boating and navigation activities. The period covered by this first report has been used to develop specific methodology and instrumentation for measuring turbidity, suspended solids and underwater irradiance for conditions found in the middle abd lower reaches of the River Great Ouse. Sampling strategies have been developed and an extensive sampling programme is now underway covering phytoplankton, suspended solids and turbidity in relation to algal epiphyte growth on underwater macrophytes. Preliminary data are presented relating light levels on the river bed to the river bed profile, turbidity levels and phytoplankton chlorophyll a concentrations. Studies are underway concerning the extent of macrophyte cover and periphyton densities.

Use of pop-up satellite archival tag technology to study postrelease survival of and habitat use by estuarine and coastal fishes: an application to striped bass (Morone saxatilis)

Pop-up satellite archival tags (PSATs) have been used to study movements, habitat use, and postrelease survival of large pelagic vertebrates, but the size of these tags has historically precluded their use on smaller coastal species. To evaluate a new generation of smaller PSATs for the study of postrelease survival and habitat use of coastal species, we attached Microwave Telemetry, Inc., X-tags to ten striped bass (Morone saxatilis) 94–112 cm total length (TL) caught on J hooks and circle hooks during the winter recreational fishery in Virginia. Tags collected temperature and depth information every five minutes and detached from the fish after 30 days. Nine of the ten tags released on schedule and eight transmitted 30% to 96% (mean 78.6%) of the archived data. Three tags were physically recovered during or after the transmission period, allowing retrieval of all archived data. All eight striped bass whose tags transmitted data survived for 30 days after release, including two fish that were hooked deeply with J hooks. The eight fish spent more than 90% of their time at depths less than 10 m and in temperatures of 6–9°C, demonstrated no significant diel differences in depth or temperature utilization (P>0.05), and exhibited weak periodicities in vertical movements consistent with daily and tidal cycles.

Sensitivity of angler benefit estimates from a model of recreational demand to the definition of the substitute sites considered by the angler

Fishery managers are mandated to understand the effects that environmental damage, fishery regulations, and habitat improvement projects have on the net benefits that recreational anglers derive from their sport. Since 1994, the National Marine Fisheries Service (NMFS) has worked to develop a consistent method for estimating net benefits through site choice models of recreational trip demand. In estimating net benefits with these models, there is a tradeoff between computational efficiency and angler behavior in reality. This article examines this tradeoff by considering the sensitivity of angler-welfare estimates for an increase in striped bass (Morone saxatalis) angling quality across choice sets with five travel distance cutoffs and compares those estimates to a model with an unrestricted choice set. This article shows that 95% confidence intervals for welfare estimates of an increase in the striped bass catch and keep rate overlap for all distance-based choice sets specified here.

Fish assemblages found in tidal-creek and seagrass habitats in the Suwannee River estuary

Fish assemblages were investigated in tidal-creek and seagrass habitats in the Suwannee River estuary, Florida. A total of 91,571 fish representing 43 families were collected in monthly seine samples from January 1997 to December 1999. Tidal creeks supported greater densities of fish (3.89 fish/m2; 83% of total) than did seagrass habitats (0.93 fish/m2). We identified three distinct fish assemblages in each habitat: winter−spring, summer, and fall. Pinfish (Lagodon rhomboides), pigfish (Orthopristis chrysoptera), and syngnathids characterized seagrass assemblages, whereas spot (Leiostomus xanthurus), bay anchovy (Anchoa mitchilli), silversides (Menidia spp.), mojarras (Eucinostomus spp.), and fundulids characterized tidal-creek habitats. Important recreational and commercial species such as striped mullet (Mugil cephalus) and red drum (Sciaenops ocellatus) were found primarily in tidal creeks and were among the top 13 taxa in the fish assemblages found in the tidal-creek habitats. Tidal-creek and seagrass habitats in the Suwannee River estuary were found to support diverse fish assemblages. Seasonal patterns in occurrence, which were found to be associated with recruitment of early-life-history stages, were observed for many of the fish species.

Length at maturity in three pelagic sharks (Lamna nasus, Isurus oxyrinchus, and Prionace glauca) from New Zealand

Reproductive data collected from porbeagle, shortfin mako, and blue sharks caught around New Zealand were used to estimate the median length at maturity. Data on clasper development, presence or absence of spermatophores or spermatozeugmata, uterus width, and pregnancy were collected by observers aboard tuna longline vessels. Direct maturity estimates were made for smaller numbers of sharks sampled at recreational fishing competitions. Some data sets were sparse, particularly over the vital maturation length range, but the availability of multiple indicators of maturity made it possible to develop estimates for both sexes of all three species. Porbeagle shark males matured at 140–150 cm fork length and females at about 170–180 cm. New Zealand porbeagles therefore mature at shorter lengths than they do in the North Atlantic Ocean. Shortfin mako males matured at 180–185 cm and females at 275 –285 cm. Blue shark males matured at about 190 –195 cm and females at 170–190 cm; however these estimates were hampered by small sample sizes, difficulty obtaining representative samples from a population segregated by sex and maturity stage, and maturation that occurred over a wide length range. It is not yet clear whether regional differences in median maturity exist for shortfin mako and

Age, growth, mortality, and radiometric age validation of gray snapper (Lutjanus griseus) from Louisiana

The gray snapper (Lutjanus griseus) is a temperate and tropical reef fish that is found along the Gulf of Mexico and Atlantic coasts of the southeastern United States. The recreational fishery for gray snapper has developed rapidly in south Louisiana with the advent of harvest and seasonal restrictions on the established red snapper (L. campechanus) fishery. We examined the age and growth of gray snapper in Louisiana with the use of cross-sectioned sagittae. A total of 833 specimens, (441 males, 387 females, and 5 of unknown sex) were opportunistically sampled from the recreational fishery from August 1998 to August 2002. Males ranged in size from 222 to 732 mm total length (TL) and from 280 g to 5700 g total weight (TW) and females ranged from 254 to 756 mm TL and from 340 g to 5800 g TW. Both edge analysis and bomb radiocarbon analyses were used to validate otolith-based age estimates. Ages were estimated for 718 individuals; both males and females ranged from 1 to 28 years. The von Bertalanffy growth models derived from TL at age were Lt = 655.4{1–e[–0.23(t)]} for males, Lt = 657.3{1–e[– 0.21(t)]} for females, and L t = 656.4{1–e[– 0.22 (t)]} for all specimens of known sex. Catch curves were used to produce a total mortality (Z) estimate of 0.17. Estimates of M calculated with various methods ranged from 0.15 to 0.50; however we felt that M= 0.15 was the most appropriate estimate based on our estimate of Z. Full recruitment to the gray snapper recreational fishery began at age 4, was completed by age 8, and there was no discernible peak in the catch curve dome.

Transboundary Movement of Atlantic Istiophorid Billfishes Among International and U.S. Domestic Management Areas Inferred from Mark-Recapture Studies

Billfish movements relative to the International Commission for the Conservation of Atlantic Tunas management areas, as well as U.S. domestic data collection areas within the western North Atlantic basin, were investigated with mark-recapture data from 769 blue marlin, Makaira nigricans, 961 white marlin, Tetrapturus albidus, and 1,801 sailfish, Istiophorus platypterus. Linear displacement between release and recapture locations ranged from zero (all species) to 15,744 km (mean 575, median 119, SE 44) for blue marlin, 6,523 km (mean 719, median 216, SE 33) for white marlin, and 3,845 km (mean 294, median 98, SE 13) for sailfish. In total, 2,824 (80.0%) billfish were recaptured in the same management area of release. Days at liberty ranged from zero (all species) to 4,591 (mean 619, median 409, SE 24) for blue marlin, 5,488 (mean 692, median 448, SE 22) for white marlin, and 6,568 (mean 404, median 320, SE 11) for sailfish. The proportions (per species) of visits were highest in the Caribbean area for blue marlin and white marlin, and the Florida East Coast area for sailfish. Blue marlin and sailfish were nearly identical when comparing the percent of individuals vs. the number of areas visited. Overall, white marlin visited more areas than either blue marlin or sailfish. Seasonality was evident for all species, with overall results generally reflecting the efforts of the catch and release recreational fishing sector, particularly in the western North Atlantic. This information may be practical in reducing the uncertainties in billfish stock assessments and may offer valuable insight into management consideration of time-area closure regulations to reduce bycatch mortality of Atlantic billfishes.

Life after Catch and Release

Since 1988 regulations have required U.S. longline fishermen to release all Atlantic white marlin, Tetrapturus albidus. By the late 1990’s, approximately 99% of Atlantic white marlin caught by U.S. recreational fishermen were released. Recent studies using PSAT technology indicate that not all released fish survive and that a minor change in hook type, 0–5° offset circle hooks rather than straight-shank “J” hooks, may have a profound effect on post release mortality. Beginning in 2004, sea turtle mitigation measures have required U.S. longline fishermen to use circle hooks. Estimates of total catch, releases, and post release mortality of Atlantic white marlin caught by U.S. recreational fishermen were made in order to evaluate the potential reduction in mortality that may be realized by requiring the use of circle hooks rather than straight-shank “J” hooks by U.S. recreational fishermen. These estimates were compared to estimates of Atlantic white marlin caught by the U.S. longline fishery