Population trends of seabirds in Mexican Islands at the California Current System.

The Baja California Pacific Islands (BCPI) is a seabird hotspot in the southern California Current System supporting 129 seabird breeding populations of 23 species and over one million birds annually. These islands had a history of environmental degradation because of invasive alien species, human disturbance, and contaminants that caused the extirpation of 27 seabird populations. Most of the invasive mammals have been eradicated and colonies have been restored with social attraction techniques. We have recorded the number of breeding pairs annually for most of the colonies since 2008. To assess population trends, we analyzed these data and show results for 19 seabird species on ten island groups. The maximum number of breeding pairs for each nesting season was used to estimate the population growth rate (λ) for each species at every island colony. We performed a moving block bootstrap analysis to assess whether seabird breeding populations are increasing or decreasing. San Benito, Natividad, and San Jerónimo are the top three islands in terms of abundance of breeding pairs. The most widespread species is Cassin's Auklet (Ptychoramphus aleuticus) with 14 colonies. Thirty-one populations of 14 species are significantly increasing while eleven populations of seven species are decreasing. We did not find statistical significance for 19 populations, however, 15 have λ>1 which suggest they are growing. Twelve of the 18 species for which we estimated a regional population trend are significantly increasing, including seven surface-nesting species: Brandt's Cormorant (Phalacrocorax penicillatus), Brown Pelican (Pelecanus occidentalis), Caspian Tern (Hydroprogne caspia), Double-crested Cormorant (P. auritus), Elegant Tern (Thalasseus elegans), Laysan Albatross (Phoebastria immutabilis) and Western Gull (Larus occidentalis), and five burrow-nesting species: Ainley's (Hydrobates cheimomnestes), Ashy (H. homochroa) and Townsend's (H. socorroensis) Storm-Petrels, and Craveri's (Synthliboramphus craveri) and Guadalupe (S. hypoleucus) Murrelets. The BCPI support between 400,000 and 1.4 million breeding individuals annually. Our results suggest that these islands support healthy and growing populations of seabirds that have shown to be resilient to extreme environmental conditions such as the "Blob", and that such resilience has been strengthen from conservation and restoration actions such as the eradication of invasive mammals, social attraction techniques and island biosecurity.

Sexual Dimorphism and Foraging Trips of the Laysan Albatross (Phoebastria immutabilis) on Guadalupe Island.

Sexual dimorphism in the Laysan albatross (Phoebastria immutabilis) on Guadalupe Island was evaluated during the breeding seasons of 2015-2018 by measuring and comparing 10 morphological attributes: cranial length, bill length, nostril length, cranial width, bill height, bill width, tarsus length, closed wing length, opened wing length, and wingspan length in reproductive adults (n = 135). Males were larger than females across all traits (Student's t-test, p < 0.05, p < 0.05). We created a logistic model using stepwise regression to predict sex based on morphological variables. This model indicated four significant morphological predictor variables (z < 0.05) and was able to successfully predict the sex of P. immutabilis individuals in more than 90% of the cases. Based on these predictor variables, a web app was developed to determine the sex of the Laysan albatross in the field, providing a non-invasive method for rapid data collection that reduces costs and handling times while improving conservation efforts. We tracked Laysan albatross (n = 36) during breeding seasons and found no significant differences between females and males for either trip length (GLMM, F = 0.017, DF = 1, 1, p = 0.917 > 0.05) or maximum trip distance (GLMM, F = 0.374, DF = 1, 1, p = 0.651 > 0.05). Our results suggest that both sexes show a strong preference to travel to highly productive coastal waters northeast of the breeding colony that are influenced by the California Current. The present research will serve to establish a baseline to protect this species on Guadalupe Island and highlights the importance of understanding sexual dimorphism in at-risk seabird species.

Plantas silvestres consumidas como tés recreativos por grupos de rancheros en Baja California Sur, México / Wild plants consumed as recreational teas by groups of ranchers in Baja California Sur, Mexico

Antecedentes y Objetivos: Los tés recreativos son bebidas preparadas, por infusión/ebullición, de diferentes partes de plantas que se consumen en un entorno social/alimenticio. Se consideran generalmente saludables y con usos medicinales, aunque ese no es su único propósito de consumo. En México, los tés recreativos prácticamente no se mencionan en los estudios etnobotánicos. Este estudio describe la etnobotánica, contenido de fenólicos y actividad antioxidante de plantas silvestres empleadas como tés recreativos en dos rancherías de las zonas montañosas de la región de Los Cabos, Baja California Sur, México: Reserva de la Biosfera Sierra La Laguna y comunidad San Blas-Cacachilas. Métodos: La información etnobotánica se obtuvo mediante encuestas semi-estructuradas y estancias con los rancheros de ambas comunidades. Se calculó el porcentaje de citas, preferencia y valor cultural de cada especie registrada, además de describir sus usos medicinales adicionales. El contenido de fenólicos y actividad antioxidante se determinó por métodos colorimétricos y fueron correlacionados con parámetros etnobotánicos. Resultados clave: Se registraron 12 taxa de plantas silvestres para elaborar tés recreativos, 11 en Sierra La Laguna y seis en San Blas-Las Cacachilas. La damiana (Turnera diffusa) obtuvo el mayor valor cultural (71.2%), seguido de margarita (Aloysia barbata) (41.1%) y anís silvestre (Tagetes filifolia/T. micrantha) (21.5%). Los tés recreativos tuvieron sus principales usos medicinales como antigripales/antitusivos y relajantes generales. El contenido de antioxidantes presentó correlación negativa con el porcentaje de citas y la preferencia. Los usos etnofarmacológicos de A. barbata y el helecho peyote (Pellaea ternifolia) son descritos por primera vez, y se documentaron nuevos usos para la damiana y el cerezo (Prunus serotina). Conclusiones: Los rancheros de Baja California Sur tienen gran afinidad por el consumo de tés recreativos de plantas silvestres, y aquellos usados para tratar padecimientos comunes como gripe/tos o estrés son los preferidos. El presente es el primer estudio etnobotánico específico para tés recreativos en México.

Molecular genetic analysis of two native desert palm genera, Washingtonia and Brahea, from the Baja California Peninsula and Guadalupe Island.

The complex geological and ecological processes that have generated high levels of biodiversity and endemism in the Baja California Peninsula have been the subject of intensive study. However, relatively little is known about phylogeography of the iconic endemic palm species of this region. We therefore analyzed a total of 2,294 bp of chloroplast and 738 bp of nuclear sequence data in 169 samples of five native palm species from Baja California, Sonora and Guadalupe Island. We found that Washingtonia and Brahea palms had low levels of genetic diversity and were highly structured, with the majority of species and major geographic regions being characterized by distinct haplotypes. We also found strong support for currently recognized species in Washingtonia, but our results were less clear cut for Brahea due to haplotype sharing. Furthermore, patterns of population structure were broadly consistent with historical vicariant events such as the inundation of the Isthmus of La Paz, the formation of the Sea of Cortez, and the more recent colonization and isolation of Guadalupe Island's palms. Our findings contribute toward a growing appreciation of the complexity of plant responses to past geological changes and also provide valuable baseline genetic data on relict American palm species.

Environmental traditional knowledge in a natural protected area as the basis for management and conservation policies.

Ethnobotany is an adequate tool to identify the most import wild edible plants used by local people and to develop strategies for its sustainable use and policy making. This research records the wild edible plants used by the inhabitants of the Sierra la Laguna Biosphere Reserve, in Mexico, and identified priority species for sustainable development. The employed quantitative approach included the application of a food-oriented index named Food Significance Index (FSI), which integrated cultural, agricultural and food parameters; moreover, it used multivariate analysis to identify priority edible species for use and/or conservation. Fifty taxa were identified as the most important wild edible plants in the reserve, integrated into five priority groups. Foods in priority group 1 had the highest culinary diversity by grouping three fruits (Ficus petiolaris, Stenocereus thurberi, and Cyrtocarpa edulis), one almond-like seed (Cnidoscolus maculatus), one vegetable (Matelea cordifolia), and one condiment (Capsicum annuum). Priority groups 2-5 were selective for one or two types of food, such as fruits, teas, or seeds. Since group 1 was the most diverse, the FSI and the employed strategy permitted to identify the priority wild edible plant species with the highest potential for food security. The selected six species should be included in the future management program of the reserve as the priority wild edible plants to develop strategies for conservation, sustainable use, and improvement of the local population income. General policies to manage the selected six species are outlined.

The human footprint in Mexico: physical geography and historical legacies.

Using publicly available data on land use and transportation corridors we calculated the human footprint index for the whole of Mexico to identify large-scale spatial patterns in the anthropogenic transformation of the land surface. We developed a map of the human footprint for the whole country and identified the ecological regions that have most transformed by human action. Additionally, we analyzed the extent to which (a) physical geography, expressed spatially in the form of biomes and ecoregions, compared to (b) historical geography, expressed as the spatial distribution of past human settlements, have driven the patterns of human modification of the land. Overall Mexico still has 56% of its land surface with low impact from human activities, but these areas are not evenly distributed. The lowest values are on the arid north and northwest, and the tropical southeast, while the highest values run along the coast of the Gulf of Mexico and from there inland along an east-to-west corridor that follows the Mexican transversal volcanic ranges and the associated upland plateau. The distribution of low- and high footprint areas within ecoregions forms a complex mosaic: the generally well-conserved Mexican deserts have some highly transformed agro-industrial areas, while many well-conserved, low footprint areas still persist in the highly-transformed ecoregions of central Mexico. We conclude that the spatial spread of the human footprint in Mexico is both the result of the limitations imposed by physical geography to human development at the biome level, and, within different biomes, of a complex history of past civilizations and technologies, including the 20th Century demographic explosion but also the spatial pattern of ancient settlements that were occupied by the Spanish Colony.

Decades of Experience in the Diagnosis of Dengue Fever in the Northwest of Mexico.

BACKGROUND: The State of Baja California Sur is in an arid region of Mexico, the southern half of the Baja California Peninsula. Given its aridity and physical isolation from mainland Mexico, there were no records of dengue fever in the state before 1985. Until now, no data on dengue incidence had been published. OBJECTIVE: To study some epidemiological features of dengue fever in Baja California Sur, Mexico in the last 30 years. METHODS: Total number of cases, general population, sex, age groups, serotypes, mortality, and incidence data were analyzed. RESULTS: There was a 652% increase in reported cases from 2012 through 2014. Age groups mostly affected were adults aged 15-24 and 45-64 years old. CONCLUSIONS: This study makes a thorough analysis of the incidence of dengue and makes recommendations to face the epidemiological challenge.

[Megapitaria squalida (Bivalvia: Veneridae) fishery landings and temperature relationship in Bahía de la Paz, México]. / Relación entre las capturas de Megapitaria squalida (Bivalvia: Veneridae) y la temperatura superficial del mar en la Bahía de la Paz, Baja California Sur, México.

The clam Megapitaria squalida is a fishing resource with increasing importance in Northwestern Mexico. Nevertheless, this fishery has shown important variations that could be related to environmental factors. To assess this, monthly landings of M. squalida were analyzed during 2002-2005 for Bahía de La Paz, B.C.S., and were related with monthly time series of sea surface temperature, derived from MODIS-Aqua Sensor. The results showed a positive and significant relationship between sea surface temperature and clam landings. The likely impact of anomalous conditions of sea temperature on this resource is discussed.

Relación entre las capturas de Megapitaria squalida (Bivalvia: Veneridae) y la temperatura superficial del mar en la Bahía de la Paz, Baja California Sur, México

Megapitaria squalida (Bivalvia: Veneridae) fishery landings and temperature relationship in Bahía de la Paz, México. The clam Megapitaria squalida is a fishing resource with increasing importance in Northwestern Mexico. Nevertheless, this fishery has shown important variations that could be related to environmental factors. To assess this, monthly landings of M. squalida were analyzed during 2002-2005 for Bahía de La Paz, B.C.S., and were related with monthly time series of sea surface temperature, derived from MODIS-Aqua Sensor. The results showed a positive and significant relationship between sea surface temperature and clam landings. The likely impact of anomalous conditions of sea temperature on this resource is discussed. Rev. Biol. Trop. 59 (1): 151-157. Epub 2011 March 01.

La almeja chocolate Megapitaria squalida es un recurso pesquero con creciente importancia en el noroeste de México al registrarse un incremento en los volúmenes de captura. Sin embargo, esta pesquería ha observado variaciones importantes en las capturas que podrían estar relacionadas con factores ambientales. Se obtuvieron datos mensuales de producción de M. squalida durante 2002- 2005 y se estimaron series de tiempo de temperatura superficial del mar en la Bahía de La Paz B.C.S. a partir de imágenes mensuales derivadas del sensor MODIS-Aqua. Los resultados indican una relación positiva significativa entre la temperatura superficial del mar y los volúmenes de captura, razón por la cual nuestro trabajo tiene como objetivo estudiar las relaciones entre capturas de Megapitaria squalida (Bivalvia: Veneridae) y la temperatura superficial del mar en La Bahía de la Paz, Baja California Sur, México.

Perceptions of a fishing community about benefits, environmental impacts and use of resources of isla cerralvo, a protected island in the Gulf of California, Mexico / Percepciones de una comunidad pesquera acerca de beneficios, impactos ambientales y uso de recursos en Isla Cerralvo, área protegida del Golfo de California, México / Percepções de uma comunidade pesqueira sobre beneficios, impactos ambientais e uso de recursos na ilha cerralvo, área protegida do Golfo de California, México

Perceptions about protected areas by local communities have a direct effect on their attitudes and can influence collective strategies of resource use. This study examines the knowledge of La Ventana fishing community about the protection status, perceived benefits and environmental impacts of Isla Cerralvo, a protected island in the Gulf of California, Mexico. It focuses on the reasons for hunting feral goats and reactions toward the hunting management policy, and evaluates the relationship between these concerns and the community’s demographic and socio-economic variables. Data were collected through a questionnaire survey. The findings indicate that a substantial number of inhabitants do not know that the island had a protected status; therefore, reinforcement of environmental education programs is needed and alternatives are proposed. Perceived economic and non-economic benefits for the island were influenced by gender, and they can be used to encourage the local fishing community to support conservation. The main perceived environmental impact on Isla Cerralvo was the presence of garbage, and this was influenced by gender, age, and education level. A new management scheme about feral goat hunting is needed since the main use of goat meat was family consumption; inhabitants with low income actively hunted goats more frequently than those with higher incomes, reflecting a subsistence economy; and most inhabitants believe that goat hunting should be allowed.

La percepción hacia las áreas protegidas de las comunidades locales afecta directamente sus actitudes y puede influenciar las estrategias colectivas del uso de los recursos. Este estudio evalúa el conocimiento de la comunidad pesquera local de La Ventana respecto al estatus de protección, beneficios e impactos ambientales percibidos de la Isla Cerralvo, área protegida del Golfo de California, México; las razones para cazar cabras ferales; y la opinión respecto a las políticas de manejo de esta práctica. La relación entre dichas percepciones y algunas variables demográficas y socio-económicas de la comunidad fue evaluada. Los datos fueron obtenidos a través de entrevistas aplicadas a los residentes de la comunidad. Los resultados indican que gran número de habitantes desconocen el estatus de protección de la isla, evidenciando la necesidad de reforzar los programas de educación ambiental, por lo que se proponen alternativas. Los beneficios económicos y no económicos percibidos variaron según el género y pueden ser usados para motivar a la comunidad a apoyar la conservación de la isla. El principal impacto ambiental percibido en la isla fue la presencia de basura, siendo esta percepción influida por género, edad y nivel educativo. Un nuevo esquema de manejo de cacería de cabras es necesario, considerando que el principal uso de la carne de cabra fue el consumo familiar; los habitantes con bajos ingresos activamente cazan cabras más frecuentemente que aquellos con un mayor ingreso, lo cual refleja una necesidad económica; y la mayoría opina que la cacería de cabras debería ser permitida.

A percepção para as áreas protegidas das comunidades locais afeta diretamente suas atitudes e pode influenciar as estratégias coletivas do uso dos recursos. Este estudo avalia o conhecimento da comunidade pesqueira local de "La Ventana" em relação ao status de proteção, benefícios e impactos ambientais percebidos da Ilha Cerralvo, área protegida do Golfo de Califórnia, México; as razões para caçar cabras (Capra hircus); e a opinião em relação às políticas de manipulação desta prática. A relação entre ditas percepções e algumas variáveis demográficas e socioeconômicas da comunidade foi avaliada. Os dados foram obtidos a través de entrevistas aplicadas aos residentes da comunidade. Os resultados indicam que grande número de habitantes desconhece o status de proteção da ilha, evidenciando a necessidade de reforçar os programas de educação ambiental, pelo que se propõem alternativas. Os benefícios econômicos e não econômicos percebidos variaram segundo o gênero e podem ser usados para motivar a comunidade a apoiar a conservação da ilha. O principal impacto ambiental percebido na ilha foi a presença de lixo, sendo esta percepção influída por gênero, idade e nível educativo. Um novo esquema de manejo de caçaria de cabras é necessário, considerando que o principal uso da carne de cabra foi o consumo familiar; os habitantes com baixos ingressos ativamente caçam cabras mais frequentemente que aqueles com um maior ingresso, o qual reflete uma necessidade econômica; e a maioria opina que a caçaria de cabras deveria ser permitida.

Four seasons abundance changes of Zalophus californianus californianus ( Lesson 1828 ), Allen, 1880, in the Gulf of California, Mexico

O leão marinho da Califórnia (Zalophus californianus californianus) é a única espécie de Otariidae (PINNIPEDIA) que vive em permanência no Golfo da Califórnia, México. Vive em grupos, principalmente em rochas, ilhas ou porções de praias de algumas ilhas. Este artigo descreve pela primeira vez as variações da abundância e estrutura populacional dos leões marinhos desta região, nas quatro estações do ano. Realizamos seis censos, entre Outubro de 1989 e Janeiro de 1992 (3 censos correspondendo ao outono e um a cada uma das outras estações. Os censos foram feitos de barco, em terra ou combinados, com contagem direta e separando os indivíduos em 5 classes de idade e sexo. As estimativas de abundância variaram de 17,162 indivíduos, em Julho de 1990 (na Primavera), ao mínimo de 7,470, no Inverno de 1992, o que representa uma redução de 10,000 leões marinhos. A hipótese da migração de parte da população para o Oceano Pacífico é discutida e comparada com a de residência da população, bem como a nossa proposta de uma dispersão dos indivíduos pelo Golfo do Califórnia.

Environmental impact assessment for alternative-energy power plants in México.

Ten Environmental Impact Assessment Reports (EIAR) were reviewed for projects involving alternative power plants in Mexico developed during the last twelve years. Our analysis focused on the methods used to assess the impacts produced by hydroelectric and geothermal power projects. These methods used to assess impacts in EIARs ranged from the most simple, descriptive criteria, to quantitative models. These methods are not concordant with the level of the EIAR required by the environmental authority or even, with the kind of project developed. It is concluded that there is no correlation between the tools used to assess impacts and the assigned type of the EIAR. Because the methods to assess impacts produced by these power projects have not changed during 2000 years, we propose a quantitative method, based on ecological criteria and tools, to assess the impacts produced by hydroelectric and geothermal plants, according to the specific characteristics of the project. The proposed method is supported by environmental norms, and can assist environmental authorities in assigning the correct level and tools to be applied to hydroelectric and geothermal projects. The proposed method can be adapted to other production activities in Mexico and to other countries.

First approach of a method to assess water quality for arid climate bay in the Gulf of California.

This work proposes a water quality model based on the pooled effects of nitrate, nitrite, ammonium, and orthophosphate concentration as the main causatives of environmental water quality changes. One of the main characteristics of the model is assigning an environmental weight for each variable (zeta(i)) according to threshold concentrations of nutrients capable of inducing water changes condition. The model validation demonstrated adequate sensitivity to different data arrangements; as observed in an arid climate bay, showing annual stratification resulting in a variable content in nitrogen-forms and phosphorous. The model can be continuously calibrated over time by adding more N and P data to specific nutrient functions, and tested on sites with high NO(3), NO(2) or NH(4) concentrations.

Identifying rainfall effects in an arid Gulf of California coastal lagoon.

At Ensenada de La Paz, a coastal lagoon on the western side of the Gulf of California, nutrient and salinity data before and after rain events were evaluated using a mass balance model to estimate the exchange of conservative and non-conservative variables with the adjacent sea. Surface salinity, nitrogen (N-NO3, N-NO2), and phosphorus (PO4) were used in the model to obtain the hydraulic balance, water residence time, and nitrogen and phosphorus fluxes. Results showed that residual volume was mainly influenced by evaporation. Rainfall and runoff increased the mixed volume and reduced water residence time. Pre-rainfall hydraulic balance conditions were reestablished about 10 days after a rain storm. Rainwater inputs also modified the quality of the coastal lagoon: the pre-rainfall scenario showed that more nitrogen is consumed than produced, and there is a phosphorus sufficiency. A rain disturbance induces a nitrogen and phosphorus increase. Eleven days after a rain storm, nitrogen and phosphorus levels did not return to the pre-rainfall scenario. Rain disturbances in arid zone coastal lagoons modify their water quality and exchange with the adjacent ocean; some management strategies are suggested.

Diseño, construcción y aplicabilidad del índice de evaluación ambiental de ecosistemas acuáticos (IEAEA) / Desing, development and applicability of the aquatic ecosystems environmental evaluation index (EEAEI)

Se diseño, construyó y comprobó la aplicabilidad de un Indice de Evaluación Ambiental de Ecosistemas Acuáticos (IEAEA) basado en calidad físico-química, contenido de contaminantes en agua y sedimentos. Los criterios de calidad se fundamentan en investigaciones recientes y límites permisibles, y se establece cuáles contaminantes representan problemas potenciales en salud pública o ecosistemas acuáticos. La validación incluyó análisis de Componentes Principales y Análisis de Sensibilidad. El IEAEA fue aplicado a resultados de 28 campañas de Tehuantepec, Oaxaca, México. Los análisis de sensibilidad se desarrollaron con los subíndices extremos y con la serie completa. La mayoría de los indicadores presentaron alta significación estadística. El modelo es robusto y los valores fluctúan cerca de la mediana. Se demostró que muestra sensibilidad a variaciones climáticas, número de variables y volúmen de datos, por lo que se comprobó su aplicabilidad

Environmental impacts of two kind of ponds for shrimp production at Northwest Mexico.

Aquaculture offers a major opportunity for the economic development of Baja California Sur (BCS), Mexico. The severely limited freshwater supply and the geographic isolation of the state place limits on other productive activities. Despite the aridity, the natural vegetation of BCS is diverse and structurally complex with a high percentage (20%) of endemic species. In this work we compare the environmental impacts produced by two kinds of aquaculture systems: coastal ponds vs. inland ponds. Construction and operation of coastal ponds does not require destruction of the natural vegetation and, as is true for inland ponds. Coastal ponds are also compatible with conservation of mangroves, sea grasses and sensitive habitats for fish and mollusks. To reduce the negative impacts of aquaculture and to protect the vegetation of Baja California Sur, we recommend the use of coastal ponds for shrimp production.

Apertura comercial y medio ambiente / Trade globalization and environment

Si bien hasta ahora el sistema de comercio se ha desarrollodo en forma independiente del sistema de protección ambiental, se están produciendo importantes esfuerzos para compatibilizar los objetivos de ambos. Estan comprometidas en esta tarea organizaciones internacionales globales, como la Organización Mundial del Comercio (OMC), instrumentos como el Tratado de Libre Comercio de América del Norte (TLCAN) y las convenciones internacionales sobre el medio ambiente que se han realizado en los últimos diez años. La relación entre comercio internacional y medio ambiente será uno de los ejes obligados de la política exportadora para los países latinoamericanos durante la presente década. En estos países se ha ido consolidando un modelo de desarrollo basado en el crecimiento de las exportaciones, por lo que sus economías se verán enfrentadas al desafío de cumplir con los estándares ambientales, por lo general más estrictos en los países compradores. En el contexto de la inserción de los países de América Latina en los mercados internacionales, el tema ambiental no ha sido, hasta ahora, tratado con la profundidad que se requiere. Esto se traduce en la escasez de estudios sobre las relaciones entre inserción global y medio ambiente, en una actitud pasiva a las exigencias externas y en la ausencia de un perfil ambiental congruente con el sistema natural, económico y social. El desarrollo de este último es indispensable para poder continuar con el proceso de inserción global, lo que implica reconocer tanto las realidades institucionales y legales del país, como el manejo y potencialidades de sus recursos naturales. Todo indica que la búsqueda de los consensos entre comercio y medio ambiente es la tendencia que predominará en la proxima década