Artisanal Shrimp Fishing in the Biosphere Reserve of the Upper Gulf of California

Las prácticas humanas irracionales sobre el medio ambiente hacen indispensable implementar medidas de protección, como la Reserva de la Biosfera del Alto Golfo de California y Delta del Río Colorado, para preservar el entorno natural y los hábitats, y así favorecer la diversidad biológica. En este trabajo se buscó determinar el soporte económico local, a través de la valoración de la vaquita marina, especie endémica en peligro de extinción que habita en la reserva, y también divulgar el proceso analítico en red, una metodología de valoración poco utilizada en el tema ambiental, que incorpora apropiadamente las interrelaciones en un esquema sistémico. El resultado arrojó que para proteger a la especie se requieren recursos adicionales a los poco más de dos millones setecientos cincuenta mil dólares estadounidenses al año, que es el valor de la vaquita. Para realizar el estudio no se contó con datos más amplios respecto a las actividades productivas en la zona, las implicaciones socioeconómicas de pesca y su impacto en la diversidad biológica. La originalidad y el valor de este trabajo radican en la metodología empleada y la interrelación que provee para el análisis. Economic valuation for the socio-environmental protection of the vaquita porpoise, an endemic speciesThe impact of irrational human practices on the environment makes it indispensable to implement measures, such as the Upper Gulf of California and Colorado River Delta Biosphere Reserve, in order to preserve the natural environment and habitats, and thus to promote biological diversity. The aim of this paper was to determine the local economic support through valuation of the vaquita porpoise, an endangered endemic species that lives in the reserve, as well as to disseminate the analytic network process, a valuation methodology little used in the environmental issue and which appropriately integrates interrelations into a systemic scheme. The result showed that for the purpose of giving protection to the species, resources additional to the little more than two million seven hundred and fifty thousand American dollars a year, which is the vaquita porpoise’s value, are needed. In carrying out this study, more comprehensive data concerning productive activities in the area, socio-economic implications of fishing and its impact on biological diversity were not available. This paper’s originality and value lie in the methodology used and the interrelation it offers for analysis.

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Analysis of the corvina gulf fishery as a function of management actions in the Upper Gulf of California, Mexico

Latin American Journal of Aquatic Research ◽

10.3856/vol41-issue3-fulltext-13 ◽

2017 ◽

Vol 41 (3) ◽

pp. 498-505

Author(s):

Joaquín Humberto Ruelas-Peña ◽

Carmen Valdez-Muñoz ◽

Eugenio Alberto Aragón-Noriega

Keyword(s):

Gulf Of California ◽

Stock Assessment ◽

Biosphere Reserve ◽

Information Criterion ◽

Fishing Effort ◽

Maximum Sustainable Yield ◽

Optimum Level ◽

Fishing Mortality ◽

Commercial Catch ◽

Management Actions

The gulf corvina (Cynoscion othonopterus), is an endemic species of the Gulf of California, and its fishery is one of the most important in the Upper Gulf of California. Two dynamic biomass models (Schaefer & Pella-Tomlinson), were used to assess the state of the stock due to the lack of enough age data for a reliable full age-structured stock assessment. The models required an historical annual time-series of the abundance index (from 1993 to 2010), derived from the commercial catch and effort data. The Akaike information criterion indicates that the best model was the Schaefer model. The maximum sustainable yield (MSY), estimated with the Schaefer model was 3.100 ton, with a maximum surplus biomass (BMSY) that will allow the capture of 8.200 ton, and a fishing effort (fMSY) of 457 boats. The fishing mortality (F = 0.43) was 26% higher than the fishing mortality at the biological reference point (F0.1 = 0.34). The average biomass from 2006 to 2010 was 52% of the optimum level of the fishery (Est2006-2010 < 1). In 1999 an increase of the fishing effort accelerated the decrease of the biomass. These results indicate that the stock has not been healthy, in spite of the Biosphere Reserve decree, because the core zone has not been respected as a prohibited zone for fishing, and because of the increased fishing effort.

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Marine diversity in the biosphere reserve of the most oceanic island in the Gulf of California: San Pedro Mártir

ZooKeys ◽

10.3897/zookeys.1062.67964 ◽

2021 ◽

Vol 1062 ◽

pp. 177-201

Author(s):

Imelda G. Amador-Castro ◽

Francisco J. Fernández-Rivera Melo ◽

Jorge Torre

Keyword(s):

Fish Species ◽

Gulf Of California ◽

Conservation Status ◽

Good Condition ◽

Biosphere Reserve ◽

Ecological Indicators ◽

Rocky Reefs ◽

San Pedro ◽

Marine Diversity ◽

Commercially Important

San Pedro Mártir island is of high biological, ecological, and fishery importance and was declared a biosphere reserve in 2002. This island is the most oceanic in the Gulf of California, and information on its rocky reefs is scarce. The present study aimed to generate the first list of conspicuous invertebrate and fish species based on in situ observations and to examine the community structure of the shallow rocky reefs of the reserve. In addition, we estimated the ecological indicators of richness, abundance, Shannon diversity, and Pielou evenness to evaluate the conservation status of the biosphere reserve. Data were collected annually from 2007 to 2017 through 2,192 underwater SCUBA transects. A total of 35 species of invertebrates and 73 species of fish were recorded. Most of the species are widely distributed along the eastern Pacific. Overall, 64% of the species found in this study are commercially important, and 11 species have been listed as protected. The abundance of commercially important invertebrate species (i.e., the sea cucumber Isostichopus fuscus and the spiny oyster Spondylus limbatus) is decreasing, while commercially important fish species have maintained their abundance with periods of increase. The ecological indicators and the abundance and size of the commercial species indicate that the reserve is in good condition while meeting its conservation objectives.

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Application of the algorithm of the deductive method of syntaxonomic classification on an example of trampled communities in the Biosphere Reserve Křivoklátsko (Central Bohemia)

Feddes Repertorium ◽

10.1002/fedr.4921070114 ◽

1996 ◽

Vol 107 (1-2) ◽

pp. 103-133

Author(s):

J. Dostálek

Keyword(s):

Biosphere Reserve ◽

Deductive Method

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Review for "Geochemistry of sands from the Huatabampo and Altata beaches, Gulf of California, Mexico"

10.1002/gj.3864/v2/review1 ◽

2020 ◽

Author(s):

Inocente Espinoza

Keyword(s):

Gulf Of California

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Review for "Geochemistry of sands from the Huatabampo and Altata beaches, Gulf of California, Mexico"

10.1002/gj.3864/v1/review1 ◽

2020 ◽

Author(s):

B. Singh

Keyword(s):

Gulf Of California

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Thysanoptera diversity associated with Mexican lemon (Citrus aurantifolia Christm.)

RECUBRIMIENTO COMESTIBLE CON BASE DE PIÑON MEXICANO (Jatropha curcas) SOBRE LA CALIDAD DE CHAYOTE MINIMAMENTE PROCESADO ◽

10.32854/agrop.vi.1761 ◽

2020 ◽

Vol 13 (9) ◽

Author(s):

Francisco Javier Avendaño-Gutiérrez ◽

Salvador Aguirre Paleo ◽

Alejandro Morales Hernández ◽

Venecia Quesadas-Béjar

Keyword(s):

Biosphere Reserve ◽

Simple Random Sampling ◽

Diversity Indices ◽

Diaphorina Citri ◽

Program Calculation ◽

Homogeneous Relation ◽

Candidatus Liberibacter ◽

Scirtothrips Citri ◽

Species Richness And Abundance ◽

First Time

Objective: To calculate the monthly relative abundance of Thysanoptera species, according to the Margalef, Simpson and Shannon-Wiener diversity indices. Design / Methodology / Approach: The work was carried out in three geographic units with conventional management, during January-December, 2019 in the Reserva de la Biosfera Zicuirán-Infiernillo (Biosphere Reserve), Michoacán, Mexico. In each unit, 10 trees were selected through simple random sampling. Thrips counts were performed on ten shoots per tree every 15 d, for a total of 7200 shoots in the three geographic units. Thysanoptera individuals were placed in entomological jars. The variables were: number of thrips collected per shoot in sampled tree and geographic unit (orchard). To estimate the specific richness and structure of species, the program "calculation of diversity indices DIVERS" was used. Results: In the three geographical units studied, the recorded presence of Thysanoptera accounted for 12 to 17 species. For Nueva Italia 12 recorded species, two were permanent (16.66%), five abundant (41.66%), one scarce (8.3%) and four rare (33.33%). In Zicuirán, three species were permanent (17.64%), six abundant (35.29%), two scarce (11.76%) and six rare (35.29%). In Los Hoyos, four species were permanent (26.66%), four abundant (26.66%) and seven rare (46.66%). The abundance of species was represented by the genus Frankliniella and the species Scolothrips sexmaculatus and Scirtothrips citri. The highest species richness and abundance was found from January to May. In October and November, the value of the calculated indices was zero, which shows less richness and abundance of individuals. The best species uniformity was recorded during January and December, which meant a more stable and homogeneous relation. Study limitations/Implications. Pest resurgence, presence of Candidatus Liberibacter spp. and its vector Diaphorina citri. Findings / Conclusions: in Nueva Italia, 12 species were taxonomically determined; in Los Hoyos 15, and in Zicuirán 17 species, which are reported for the first time in the state of Michoacán, Mexico. At the geographic unit "Los Hoyos" diversity was higher, uniform and stable.

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Dissolved oxygen and temperature best predict deep-sea fish community structure in the Gulf of California with climate change implications

Marine Ecology Progress Series ◽

10.3354/meps13240 ◽

2020 ◽

Vol 637 ◽

pp. 159-180

Author(s):

ND Gallo ◽

M Beckwith ◽

CL Wei ◽

LA Levin ◽

L Kuhnz ◽

...

Keyword(s):

Climate Change ◽

Community Structure ◽

Community Composition ◽

Environmental Conditions ◽

Deep Sea ◽

Gulf Of California ◽

Fish Community ◽

Demersal Fish ◽

Fish Community Structure ◽

Explained Variance

Natural gradient systems can be used to examine the vulnerability of deep-sea communities to climate change. The Gulf of California presents an ideal system for examining relationships between faunal patterns and environmental conditions of deep-sea communities because deep-sea conditions change from warm and oxygen-rich in the north to cold and severely hypoxic in the south. The Monterey Bay Aquarium Research Institute (MBARI) remotely operated vehicle (ROV) ‘Doc Ricketts’ was used to conduct seafloor video transects at depths of ~200-1400 m in the northern, central, and southern Gulf. The community composition, density, and diversity of demersal fish assemblages were compared to environmental conditions. We tested the hypothesis that climate-relevant variables (temperature, oxygen, and primary production) have more explanatory power than static variables (latitude, depth, and benthic substrate) in explaining variation in fish community structure. Temperature best explained variance in density, while oxygen best explained variance in diversity and community composition. Both density and diversity declined with decreasing oxygen, but diversity declined at a higher oxygen threshold (~7 µmol kg-1). Remarkably, high-density fish communities were observed living under suboxic conditions (<5 µmol kg-1). Using an Earth systems global climate model forced under an RCP8.5 scenario, we found that by 2081-2100, the entire Gulf of California seafloor is expected to experience a mean temperature increase of 1.08 ± 1.07°C and modest deoxygenation. The projected changes in temperature and oxygen are expected to be accompanied by reduced diversity and related changes in deep-sea demersal fish communities.

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