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Timothy C Haab - One of the best experts on this subject based on the ideXlab platform.
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southeast marine recreational Fishery statistical survey distance and catch based choice sets
Marine Resource Economics, 1999Co-Authors: John C Whitehead, Timothy C HaabAbstract:In this paper we estimate the economic value associated with marine recreational fishing in the southeast United States using the random utility model. The data used is the Southeast (North Carolina to Louisiana) Marine Recreational Fishery Statistics Survey (SE MRFSS). The geographic extent of the market and potential catch are used to determine the effect of choice set definition on random utility model parameter and welfare estimates. We find that choice sets based on distance or catch do not lead to large differences in the compensating variation of a fishing trip. Defining choice sets based on catch does lead to insignificant estimates of the effect of one measure of site quality on site selection. We also find differences in the value of an additional fish when comparing alternative measures of site quality.
Ángel Guerra - One of the best experts on this subject based on the ideXlab platform.
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Reliability of a model based on a short Fishery Statistics survey: application to the Northeast Atlantic monkfish Fishery
Ices Journal of Marine Science, 2004Co-Authors: Francisco Rocha, Joaquín Gracia, Ángel F. González, Carlos M. Jardon, Ángel GuerraAbstract:A model based on a short Fishery Statistics survey was applied to estimate catch and catch per unit effort (cpue) of the Galician monkfish (Lophius spp.) trawl fleet during 1998. In all, 35 interviews were conducted with fisheries personnel in ICES Divisions IXa, VIIIc, VIIId, and VIIIe (coastal offshore fishing grounds) and 44 in VIIb, VIIc, VIIj, and VIIk (Grand Sole fishing ground). Reliability of the model estimates was tested using: (i) registered fish market landings at 38 ports; (ii) landings data from sale invoices at six of these ports (93.8% of total landings of the species); (iii) 29 observers’ trips made on board coastal offshore trawlers and the logbook of one Grand Sole trawler. Estimated mean total catch from the model was 5110 t (602 t coastal offshore, 4508 t in Grand Sole) and cpue values were 36.2 kg haul � 1 vessel � 1 coastal offshore and 104.4 kg haul � 1 vessel � 1 Grand Sole. Differences between the values of cpue estimated by the model and those determined directly in both fisheries were not significant. However, there were differences between the total catch estimated by the model and the total landings deduced from sale invoices and Galician fish market information.
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THE SMALL-SCALE SQUID HAND-JIG Fishery OFF THE NORTHWESTERN IBERIAN PENINSULA: APPLICATION OF A MODEL BASED ON A SHORT SURVEY OF Fishery Statistics
Fisheries Research, 1996Co-Authors: Fernando Simón, Francisco Rocha, Ángel GuerraAbstract:Abstract A small-scale squid hand-jig Fishery targeting the squids Loligo vulgaris and Loligo forbesi exists in the northwestern Iberian Peninsula. Its importance is evaluated using a model based on a short survey of Fishery Statistics. A total of 46 ports in Galicia operate this Fishery. These ports were classified into three categories, according to characteristics relevant to the length of season in the Fishery. Aguino, Cedeira and Mugardos were selected as “model ports” for each of the three categories. The catch per unit effort and total catch were estimated for each of these model ports. Total catch for each port was estimated taking into account the catch obtained in each model port multiplied by a suitable correction factor based on the number of boats in each port. The ports of each of the three categories were considered separately. Thus we can obtain the total catch of the 46 Galician ports where this fishing activity takes place. It was calculated that the small-scale hand-jig Fishery unloaded 282 t of squid in Galicia in 1992. The accuracy of the model based on a short survey of Fishery Statistics was tested by comparing estimates of catches with real squid landing data recorded in Aguino in 1992. It was observed that the difference between the estimates (15.5 and 14.6 t, respectively) was 5.8%. Information on the characteristics of this Fishery, seasonality, type and the number of fishing boats is included in this paper, which represents the first step towards assessing the magnitude of the squid resource in the hand-jig Galician Fishery.
Elizabeth A Babcock - One of the best experts on this subject based on the ideXlab platform.
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updated index of abundance for shortfin mako sharks from the u s marine recreational fisheries Statistics survey
2013Co-Authors: Elizabeth A BabcockAbstract:SUMMARY The standardized index of abundance for shortfin mako sharks from the National Marine Fisheries Service Marine Recreational Fishery Statistics Survey (MRFSS) was updated with data from 1981 through 2010. The catch per unit effort (CPUE) data were standardized using a general linear mixed model (GLMM) with year, season, fishing mode (private versus charter boat) and region included as explanatory variables. Because of the large number of zero observations, the CPUE was standardized using a delta-lognormal approach. Both the fraction of trips with a positive observation, and the delta-lognormal abundance index were highly variable, and showed a high in the mid 1990s, followed by a decline, then a stable trend over the last 10 years. RESUME L'indice d'abondance standardise du requin-taupe bleu elabore sur la base de l'enquete statistique des pecheries recreatives marines (MFRSS) du National Marine Fisheries Service des Etats-Unis a ete mis a jour avec des donnees couvrant la periode 1981-2010. Les donnees de capture par unite d'effort (CPUE) ont ete standardisees en utilisant un modele mixte lineaire generalise (GLMM) dont les variables explicatives etaient l'annee, la saison, le mode de peche (navire prive par opposition a navire affrete) et la region. En raison de la quantite elevee d'observations nulles, la CPUE a ete standardisee au moyen d'une approche delta-lognormale. La proportion des sorties presentant une observation positive tout comme l'indice d’abondance delta-lognormal etaient extremement variables et presentaient un pic au milieu des annees 1990, suivi d'une baisse et d'une tendance stable au cours des dix dernieres annees. RESUMEN
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INDICES OF BLUE, MAKO AND THRESHER SHARK ABUNDANCE DERIVED FROM U.S. ATLANTIC RECREATIONAL Fishery DATA
2008Co-Authors: Elizabeth A Babcock, Gregory SkomalAbstract:SUMMARY Standardized indices of abundance were derived for blue, Prionace glauca, shortfin mako, Isurus oxyrinchus, and thresher, Alopias vulpinus, sharks using data from recreational shark tournaments in the state of Massachusetts for the years 1991 through 2006, and for blue and shortfin mako sharks using data from the private and charter boat recreational anglers covered by the National Marine Fisheries Service Marine Recreational Fishery Statistics Survey (MRFSS), for the years 1981 through 2005. For both the MRFSS and Massachusetts tournament data, the catch per unit effort (CPUE) data were standardized using a general linear model (GLM) with year, region and tournament included as explanatory variables in the tournament data, and year, season, fishing mode (private versus charter boat) and region included as explanatory variables in the MFRFSS data. The best fit model was chosen using the Akaike information criterion (AIC). For the tournament data, blue shark CPUE increased through the late 1990s and then declined, while shortfin mako sharks showed the opposite pattern. Thresher shark CPUEs were low and variable, but appeared to increase in recent years. For the MRFSS data, significant interactions between year, area, season and fishing mode complicate interpretation of annual trends. RESUME
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indices of blue and mako shark abundance derived from u s atlantic recreational Fishery data
2005Co-Authors: Gregory Skomal, Elizabeth A Babcock, Ellen K PikitchAbstract:SUMMARY Generalized linear models were used to derive indices of abundance for blue, Prionace glauca, and shortfin mako, Isurus oxyrinchus, sharks based on two components of the U.S. Atlantic recreational Fishery: (1) the private and charter boat recreational anglers covered by the National Marine Fisheries Service Marine Recreational Fishery Statistics Survey (MRFSS, 1981-2002), and (2) Massachusetts shark tournaments (19912002). From the MRFSS data, blue shark CPUE showed different trends for different regions, seasons and fishing modes, implying that CPUE is not tracking blue shark abundance. Mako shark CPUE differed by mode for private versus charter boats, and showed no trend in either boat type. In the Massachusetts tournaments, blue shark CPUE showed different trends north and south of Cape Cod. Mako shark CPUE declined in the 1990s in Massachusetts tournaments, then increased again in 2002. RESUME
John C Whitehead - One of the best experts on this subject based on the ideXlab platform.
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southeast marine recreational Fishery statistical survey distance and catch based choice sets
Marine Resource Economics, 1999Co-Authors: John C Whitehead, Timothy C HaabAbstract:In this paper we estimate the economic value associated with marine recreational fishing in the southeast United States using the random utility model. The data used is the Southeast (North Carolina to Louisiana) Marine Recreational Fishery Statistics Survey (SE MRFSS). The geographic extent of the market and potential catch are used to determine the effect of choice set definition on random utility model parameter and welfare estimates. We find that choice sets based on distance or catch do not lead to large differences in the compensating variation of a fishing trip. Defining choice sets based on catch does lead to insignificant estimates of the effect of one measure of site quality on site selection. We also find differences in the value of an additional fish when comparing alternative measures of site quality.
Eric Foucher - One of the best experts on this subject based on the ideXlab platform.
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the european scallop fisheries for pecten maximus aequipecten opercularis chlamys islandica and mimachlamys varia
Developments in Aquaculture and Fisheries Science, 2016Co-Authors: Peter F Duncan, A R Brand, Oivind Strand, Eric FoucherAbstract:The European fisheries for Pecten maximus, Aequipecten opercularis, Mimachlamys varia and Chlamys islandica are among the best-studied scallop fisheries worldwide. This chapter provides a current perspective of the scientific research related to the four species and their fisheries, covering biology, physiology, ecology, Fishery Statistics, management and current developments in the Isle of Man, United Kingdom, Norway, France, Spain, Iceland and Greenland. The history of these fisheries demonstrates expansion, ‘boom and bust’ and terminal decline; processes still evident today. Despite their economic importance and good underlying scientific knowledge, the fisheries are often data poor regarding stock status and are typically poorly managed, despite a large number of regulations and control measures. Significant issues remain regarding entry restrictions, effort control, stock conservation and spatial management. Scallop recruitment processes are inherently unpredictable, and the subsequent complex relationship with fisheries stock status has led to experiments with closed areas to protect high-density broodstock areas, boost reproductive output and protect settlement habitats and biodiversity. Larger scale interactions between fisheries and spatial management, both positive and negative, are likely in the near future, as the EU Habitats Directive requires the establishment of marine protected areas for habitat and biodiversity features under the Natura 2000 initiative. While this will restrict the largely open access enjoyed by scallop fishermen, closed areas, as sanctuaries for scallops, and with proven Fishery benefits, are likely to be beneficial for fisheries in the longer term. The general expansion of effort and vessel capacity in European scallop fisheries, the nomadic nature of larger classes of vessel and the lack of coordinated management, particularly in the United Kingdom, has led to more locally based co-management, especially in inshore areas. This has the potential for greater resource stewardship and the promotion of more sustainable fisheries and stock conservation strategies. Consumer demand for sustainably produced seafood is driving improved management; this is particularly important given the relatively poor sustainability credentials of European scallop fisheries. Some fisheries have achieved recognition of their current management practices, but it requires significant long-term commitment by all stakeholders to gain and retain certification. It seems likely that such efforts will need to become more common if better economic returns and security for fishermen are to be achieved. Diver-based and local-management solutions may represent alternatives for large-scale dredge-dominated fisheries, but ultimately European scallop fisheries must adopt a longer term and more responsible approach.