Red de reservas marinas para la Región de las Grandes Islas, Golfo de California: protocolo del proyecto de planeación y reporte de los talleres del equipo de planeación [Marine reserves network for the Midriff Islands Region, Gulf of California, Mexico: planning protocol and progress report to the WWF Mexico & Carlos Slim Foundation Alliance]

La Región de las Grandes Islas (RGI), localizada en el acuario del mundo, el Golfo de California, es reconocida a nivel mundial por su espectacular belleza, diversidad y productividad; en ocasiones se le ha denominada como "las Galápagos del Hemisferio Norte" (Figura 1). En sus 45 islas, incluyendo las dos más grandes de México, Tiburón e Isla Ángel de la Guarda, se han registrado más de 400 especies de plantas, anfibios, reptiles y mamíferos terrestres, algunas de ellas endémicas a una o varias de las islas. En algunas de estas islas, como Rasa y San Pedro Mártir, llegan a anidar cientos de miles de aves marinas. Alrededor de este gran archipiélago, se pueden observar hasta 23 especies de mamíferos marinos, incluyendo la súper agregación de cachalotes en la cuenca San Pedro Mártir. Así como también es un sitio usado por cinco especies de tortugas marinas para hibernar y alimentarse. [English] In collaboration with researchers, agencies and NGOs, we aim to guide the design and implementation of a network of marine reserves for Midriff Islands, Gulf of California, a marine conservation hotspot. The area is one of the most important fishing regions in Mexico and livelihoods of coastal communities are threatened by depletion of fish stocks and climate change. The project aims to develop a practical approach to design networks of marine reserves that consider ecological connectivity and the effects of climate change. The project is an example of interdisciplinary and collaborative applied research, including over 25 researchers and managers from NGOs (COBI, Pronatura), universities (James Cook University, The University of Queensland, Arizona State University, SCRIPPS, The University of Arizona), and national (Mexico’s Commissions for Protected Areas and Biodiversity) and international agencies (NOAA)

Zonas susceptibles de invasión por parte del pez león en el Pacífico mexicano

Lionfish Pterois volitans/miles has invaded the western Atlantic, but is absent in the eastern tropical Pacific, even though the oceanographic conditions seem to be adequate for its establishment. This paper proposes probable Pterois spp invasion areas on the western coast of Mexico, based on ecological niche and potential distribution models, as well as species occurrence data (1985-2018) and environmental layers (2002-2017). For the environmental database, rasters of temperature, salinity, chlorophyll a and velocity of sea currents were used at average, maximum, and minimum values at the surface level, as well as average temperature and salinity at the seabed level and the type of predominant coast. Results indicated that bottom salinity, type of coast, and average surface temperature contributed 65% to the distribution model. To learn the impact of the possible invasion of Pterois spp. on local biodiversity, a spatial intersection was made between the predicted area with potential for invasion with the geographic distribution of coastal fish and the fishing areas. According to the spatial analysis, the arrival of Pterois spp. could affect almost 200 species, several of which are endemic and of commercial importance. The impact could be even greater, considering that the species is a predator of invertebrates such as crayfish and shrimp, which are important fisheries in the region.Os peixes-leões, Pterois volitans/miles, invadiram o Atlântico Ocidental, mas estão ausentes do Pacífico Oriental apesar de as condições oceanográficas parecerem adequadas para seu estabelecimento. Este trabalho propõe áreas prováveis de invasão de Pterois spp. na costa oeste do México, a partir de modelos de nicho ecológico e de distribuição potencial, baseados em dados de ocorrência da espécie (1985-2018) e capas ambientais (2002-2017). Para a base de dados ambientais, foram utilizados os matriciais de temperatura, salinidade, clorofila a e velocidade de correntes marítimas em cálculos da média, máximos e mínimos a nível da superfície, também, a média da temperatura e salinidade a nível do fundo marítimo e o tipo de costa predominante. Os resultados mostraram que a salinidade do fundo, o tipo de costa e a temperatura média na superfície forneceram 65% da contribuição no modelo de distribuição. Para saber o impacto sobre a diversidade da possível chegada de Pterois spp., foi realizada uma intersecção espacial entre a área prevista com potencial para a invasão com a distribuição geográfica de peixes costeiros e as zonas de pesca. De acordo com a análise espacial, a chegada de Pterois spp. poderia afetar quase 200 espécies de peixes das quais várias são endêmicas, incluindo algumas de importância comercial. O impacto poderia ser maior, caso seja considerado o fato de o peixe-leão ser um predador de invertebrados como o siri-azul e o camarão, considerados importantes para a pesca na região.El pez león Pterois volitans/miles, ha invadido el Atlántico occidental, pero está ausente del Pacífico oriental a pesar de que las condiciones oceanográficas parecen ser adecuadas para su establecimiento. Este trabajo propone áreas probables de invasión de Pterois spp. en la costa oeste de México, a partir de modelos de nicho ecológico y de distribución potencial, basados en datos de ocurrencia de la especie (1985-2018) y capas ambientales (2002-2017). Para la base de datos ambiental, se utilizaron rasters de temperatura, salinidad, clorofila a y velocidad de corrientes marinas en valores promedio, máximos y mínimos en el nivel superficial, además, el promedio de la temperatura y salinidad en el nivel de fondo marino y el tipo de costa predominante. Los resultados indicaron que la salinidad del fondo, el tipo de costa y la temperatura promedio en superficie aportaron 65 % de la contribución en el modelo de distribución. Para conocer el impacto de la posible llegada de Pterois spp. sobre la biodiversidad, se realizó una intersección espacial entre el área pronosticada con potencial para la invasión con la distribución geográfica de peces costeros y las zonas de pesca. De acuerdo con el análisis espacial, la llegada de Pterois spp. podría afectar a casi 200 especies de peces de las cuales, varias son endémicas e incluyen algunas de importancia comercial. El impacto podría ser mayor, si se considera que el pez león es depredador de invertebrados como jaibas y camarones, las cuales son pesquerías importantes en la región

Potential Impacts of Climate Change on Shrimps Distribution of Commercial Importance in the Gulf of California

The Gulf of California is the most productive fishing region in Mexico; its ecosystems contain a vast diversity of species with exploitation potential, some of them potentially vulnerable to climate change. This research was conducted to analyze, through habitat suitability models, the possible alterations in the distribution of the three shrimp species of the most importance for commercial fishing in the region: Litopenaeus stylirostris, Litopenaeus vannamei, and Farfantepenaeus californiensis. Habitat suitability models were built using the MaxEnt software, primary productivity data, temperature, salinity, bathymetry, substratum, coastal type, and geo-referenced occurrence records of the three species. Of the data, 70% was used on training, while the remaining 30% was used for validation. To make estimates of climate change impact on this fishery, projections on distribution of the three species from environmental forecasts generated by the intergovernmental panel on climate change until 2100 were made. The used model, that is in full development and expansion, could be considered as an applicable tool to other problems and showed efficiency rates above 90%. The species will maintain most of their historical distribution, but L. stylirostris and L. vannamei will have a new distribution area within the zones of the Magdalena-Almejas Bay and the Gulf of Ulloa, with an increase of 80% and 148% respectively; all species will have loss areas in the proportion of 16%, 2%, and 11%, respectively, along the southern Gulf of California

Designing connected marine reserves in the face of global warming

Marine reserves are widely used to protect species important for conservation and fisheries and to help maintain ecological processes that sustain their populations, including recruitment and dispersal. Achieving these goals requires well-connected networks of marine reserves that maximize larval connectivity, thus allowing exchanges between populations and recolonization after local disturbances. However, global warming can disrupt connectivity by shortening potential dispersal pathways through changes in larval physiology. These changes can compromise the performance of marine reserve networks, thus requiring adjusting their design to account for ocean warming. To date, empirical approaches to marine prioritization have not considered larval connectivity as affected by global warming. Here, we develop a framework for designing marine reserve networks that integrates graph theory and changes in larval connectivity due to potential reductions in planktonic larval duration (PLD) associated with ocean warming, given current socioeconomic constraints. Using the Gulf of California as case study, we assess the benefits and costs of adjusting networks to account for connectivity, with and without ocean warming. We compare reserve networks designed to achieve representation of species and ecosystems with networks designed to also maximize connectivity under current and future ocean-warming scenarios. Our results indicate that current larval connectivity could be reduced significantly under ocean warming because of shortened PLDs. Given the potential changes in connectivity, we show that our graph-theoretical approach based on centrality (eigenvector and distance-weighted fragmentation) of habitat patches can help design better-connected marine reserve networks for the future with equivalent costs. We found that maintaining dispersal connectivity incidentally through representation-only reserve design is unlikely, particularly in regions with strong asymmetric patterns of dispersal connectivity. Our results support previous studies suggesting that, given potential reductions in PLD due to ocean warming, future marine reserve networks would require more and/or larger reserves in closer proximity to maintain larval connectivity