Rapid Effects of Marine Reserves via Larval Dispersal

Marine reserves have been advocated worldwide as conservation and fishery management tools. It is argued that they can protect ecosystems and also benefit fisheries via density-dependent spillover of adults and enhanced larval dispersal into fishing areas. However, while evidence has shown that marine reserves can meet conservation targets, their effects on fisheries are less understood. In particular, the basic question of if and over what temporal and spatial scales reserves can benefit fished populations via larval dispersal remains unanswered. We tested predictions of a larval transport model for a marine reserve network in the Gulf of California, Mexico, via field oceanography and repeated density counts of recently settled juvenile commercial mollusks before and after reserve establishment. We show that local retention of larvae within a reserve network can take place with enhanced, but spatially-explicit, recruitment to local fisheries. Enhancement occurred rapidly (2 yrs), with up to a three-fold increase in density of juveniles found in fished areas at the downstream edge of the reserve network, but other fishing areas within the network were unaffected. These findings were consistent with our model predictions. Our findings underscore the potential benefits of protecting larval sources and show that enhancement in recruitment can be manifested rapidly. However, benefits can be markedly variable within a local seascape. Hence, effects of marine reserve networks, positive or negative, may be overlooked when only focusing on overall responses and not considering finer spatially-explicit responses within a reserve network and its adjacent fishing grounds. Our results therefore call for future research on marine reserves that addresses this variability in order to help frame appropriate scenarios for the spatial management scales of interest

Spatial distribution and risk factors of Brucellosis in Iberian wild ungulates

<p>Abstract</p> <p>Background</p> <p>The role of wildlife as a brucellosis reservoir for humans and domestic livestock remains to be properly established. The aim of this work was to determine the aetiology, apparent prevalence, spatial distribution and risk factors for brucellosis transmission in several Iberian wild ungulates.</p> <p>Methods</p> <p>A multi-species indirect immunosorbent assay (iELISA) using <it>Brucella </it>S-LPS antigen was developed. In several regions having brucellosis in livestock, individual serum samples were taken between 1999 and 2009 from 2,579 wild bovids, 6,448 wild cervids and4,454 Eurasian wild boar (<it>Sus scrofa</it>), and tested to assess brucellosis apparent prevalence. Strains isolated from wild boar were characterized to identify the presence of markers shared with the strains isolated from domestic pigs.</p> <p>Results</p> <p>Mean apparent prevalence below 0.5% was identified in chamois (<it>Rupicapra pyrenaica</it>), Iberian wild goat (<it>Capra pyrenaica</it>), and red deer (<it>Cervus elaphus</it>). Roe deer (<it>Capreolus capreolus</it>), fallow deer (<it>Dama dama</it>), mouflon (<it>Ovis aries</it>) and Barbary sheep (<it>Ammotragus lervia</it>) tested were seronegative. Only one red deer and one Iberian wild goat resulted positive in culture, isolating <it>B. abortus </it>biovar 1 and <it>B. melitensis </it>biovar 1, respectively. Apparent prevalence in wild boar ranged from 25% to 46% in the different regions studied, with the highest figures detected in South-Central Spain. The probability of wild boar being positive in the iELISA was also affected by age, age-by-sex interaction, sampling month, and the density of outdoor domestic pigs. A total of 104 bacterial isolates were obtained from wild boar, being all identified as <it>B. suis </it>biovar 2. DNA polymorphisms were similar to those found in domestic pigs.</p> <p>Conclusions</p> <p>In conclusion, brucellosis in wild boar is widespread in the Iberian Peninsula, thus representing an important threat for domestic pigs. By contrast, wild ruminants were not identified as a significant brucellosis reservoir for livestock.</p

Spat availability of commercial bivalve species recruited on artificial collectors from the northern Gulf of California. Seasonal changes in species composition

This study reports a year-round recruitment of spat of four commercial bivalve species; Pteria sterna, Euvola vogdesi, Pinctada mazatlanica and Pinna rugosa collected in the region of Puerto Peñasco, north-eastern coast of the Gulf of California. Bimonthly recruitment of commercial bivalve spat on netlon® collectors was evaluated for six sites from June 2007 to August 2008. To describe spat recruitment abundances with environmental parameters, sea surface temperature (°C) and surface chlorophyll a concentration (mg m−3) were characterized by means of monthly Aqua/MODIS satellite data. For each species a repeated measures anova was used to evaluate differences in the number of spat between months, sites and depths. Maximum sea surface temperature was recorded in August–September (~31.5°C) and the minimum in January–February (~15°C), while the minimum surface chlorophyll a was observed in June–September (mean range = 1.5–2 mg m−3) and the maximum in January–March (mean range = 2–5 mg m−3). Spat recruitment showed distinct patterns; P. sterna can be characterized as having a Winter–Spring pattern, E. vogdesi a winter pattern, while P. mazatlanica and P. rugosa a summer spat recruitment pattern. This information constitutes part of the fundamental data needed for the development of aquaculture and conservation initiatives in the region based on wild spat supply.Fil: Soria, Rodrigo Gaspar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; Argentina. University Of Arizona; Estados UnidosFil: Lavín, Miguel F.. Centro de Investigación Científica y de Educación Superior de Ensenada; MéxicoFil: Cudney Bueno, Richard. University of California Santa Cruz; Estados Unido

Presentation

En los primeros meses de 1997, el Pacífico Ecuatorial mostraba señales de un El Niño masivo inminente, y como consecuencia de las primeras predicciones, el evento recibió una enorme y sin precedentes cobertura de prensa, llamando la atención sobre la necesidad de mitigar sus efectos catastróficos en todo el mundo, sino también para tener en cuenta sus efectos moduladores en los esfuerzos económicos para mejorar la productividad económica. doi: https://doi.org/10.22201/igeof.00167169p.2003.42.3.97

Larval fish assemblages and circulation in the Eastern Tropical Pacific in Autumn and Winter

In this work, we linked larval fish assemblages with water masses and circulation in the Eastern Tropical Pacific off Mexico, during autumn 2005 and winter 2007. Four assemblages were defined. (i) The “Transitional” assemblage, with the lowest mean larval abundance and dominated by tropical mesopelagic Vinciguerria Lucelia and Diogenicthys laternatus. It was associated with modified California Current Water in winter and with modified Tropical Surface Water in autumn. (ii) The “Coastaloceanic” assemblage was found off Cabo Corrientes, with high larval abundance, and dominated by Bregmaceros bathymaster; part of this assemblage was trapped by coastal cyclonic eddies. (iii) The “Tropical A” assemblage was associated with Tropical Surface Water. It had the highest abundance and richness, and the largest number of dominant species (e.g. D. laternatus, Auxis spp.); it covered a wider area in winter than in autumn. (iv) The “Tropical B” assemblage, distinguished by the highest abundance of V. lucetia, was present only in autumn; it was associated with overall anticyclonic circulation of warm Tropical Surface Water. The agreement between larval fish assemblage distributions, water masses and mesoscale dynamics indicates that the formation and permanence of assemblages depends on the interaction of spawning strategies of different species with large-scale and mesoscale processes

Dynamic connectivity patterns from an insular marine protected area in the Gulf of California

We studied connectivity patterns from a small and isolated island in the Gulf of California (San Pedro Mártir Island Biosphere Reserve), as a source of propagules to surrounding Marine Protected Areas and fishing sites. We used a particle-tracking scheme based on the outputs of a three-dimensional numerical hydrodynamic model to assess the spatial domain to which the island exports larvae as well as larvae retention. We modeled the release of passive particles from locations around the island during the four release dates (May 15 and 31, and June 14 and 30), matching the lunar phases and the peak of the reproductive season for several commercial invertebrates and fish, at the time when currents in the Gulf typically reverse. For each simulation we analyzed the data at 15, 20 and 30 days after the release to represent different planktonic propagule durations. Particle dispersion was highly dynamic and spread over ~ 600 km along the coast over the study period. Overall, we observed potential ecological connectivity with a few key distant fishing sites that changed trough time, and potential genetic connectivity towards many near and distant sites, including all neighboring Marine Protected Areas, although not simultaneously. The percentages of particles remaining within the boundaries of the island tended to decline from May to June, and decreased with delayed planktonic propagule duration. The design of effective Marine Protected Areas should acknowledge the dynamic nature of connectivity patterns, for instance, by establishing adaptive network reserves to respond to changing ocean features that match reproductive patterns of target species and fisheries behavior.We studied connectivity patterns from a small and isolated island in the Gulf of California (San Pedro Mártir Island Biosphere Reserve), as a source of propagules to surrounding Marine Protected Areas and fishing sites. We used a particle-tracking scheme based on the outputs of a three-dimensional numerical hydrodynamic model to assess the spatial domain to which the island exports larvae as well as larvae retention. We modeled the release of passive particles from locations around the island during the four release dates (May 15 and 31, and June 14 and 30), matching the lunar phases and the peak of the reproductive season for several commercial invertebrates and fish, at the time when currents in the Gulf typically reverse. For each simulation we analyzed the data at 15, 20 and 30 days after the release to represent different planktonic propagule durations. Particle dispersion was highly dynamic and spread over ~ 600 km along the coast over the study period. Overall, we observed potential ecological connectivity with a few key distant fishing sites that changed trough time, and potential genetic connectivity towards many near and distant sites, including all neighboring Marine Protected Areas, although not simultaneously. The percentages of particles remaining within the boundaries of the island tended to decline from May to June, and decreased with delayed planktonic propagule duration. The design of effective Marine Protected Areas should acknowledge the dynamic nature of connectivity patterns, for instance, by establishing adaptive network reserves to respond to changing ocean features that match reproductive patterns of target species and fisheries behavior.Fil: Soria, Rodrigo Gaspar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; ArgentinaFil: Soria, Rodrigo Gaspar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; ArgentinaFil: Torre Cosio, Jorge. Comunidad y Biodiversidad A. C.; MéxicoFil: Torre Cosio, Jorge. Comunidad y Biodiversidad A. C.; MéxicoFil: Munguia Vega, Adrián. Comunidad y Biodiversidad A. C.; México. University of Arizona; Estados UnidosFil: Munguia Vega, Adrián. Comunidad y Biodiversidad A. C.; México. University of Arizona; Estados UnidosFil: Marinone, Silvio Guido. Centro de Investigación Científica y de Educación Superior de Ensenada; MéxicoFil: Marinone, Silvio Guido. Centro de Investigación Científica y de Educación Superior de Ensenada; MéxicoFil: Lavín, Miguel F.. Centro de Investigación Científica y de Educación Superior de Ensenada; MéxicoFil: Lavín, Miguel F.. Centro de Investigación Científica y de Educación Superior de Ensenada; MéxicoFil: Cinti, Ana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; ArgentinaFil: Cinti, Ana. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico; ArgentinaFil: Moreno Báez, Marcia. University of California at San Diego; Estados UnidosFil: Moreno Báez, Marcia. University of California at San Diego; Estados Unido