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1.
Mar Pollut Bull ; 195: 115547, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37717495

ABSTRACT

Sea turtles can bioaccumulate high concentrations of potentially toxic contaminants. To better understand trace element effects on sea turtles' health, we established reference intervals for hematological and plasma biochemical analytes in 40 in-water, foraging immature and adult Eastern Pacific green turtles (Chelonia mydas) from two coastal lagoons in Baja California Sur, quantified whole blood concentrations of eight trace elements, and assessed their correlations. Rank-order trace element concentrations in both immature and adult turtles was zinc > selenium > nickel > arsenic > copper > cadmium > lead > manganese. Immature turtles had significantly higher copper and lower nickel and zinc concentrations. Additionally, a number of relationships between trace elements and blood analytes were identified. These data provide baseline information useful for future investigations into this population, or in other geographic regions and various life-stage classes.


Subject(s)
Trace Elements , Turtles , Water Pollutants, Chemical , Animals , Trace Elements/analysis , Mexico , Copper , Nickel , Zinc , Water Pollutants, Chemical/analysis
2.
Rev. biol. trop ; Rev. biol. trop;69(4)dic. 2021.
Article in English | LILACS, SaludCR | ID: biblio-1387693

ABSTRACT

Abstract Introduction: Estimates of contemporary connectivity of the broadcast spawning coral Pocillopora verrucosa between multi-use marine protected areas (MUMPAs) are required to assess MUMPA effectiveness and their ability to enhance resilience against disturbances. Objective: To determine the genetic structure and connectivity patterns between P. verrucosa demes inside the Gulf of California and evaluate the role and effectiveness of established MUMPAS in their protection and resilience. Methods: We assessed P. verrucosa connectivity along its peninsular range (∼350 km), including five locations and three MUMPAs in the Gulf of California using six microsatellite genetic markers. Results: Population structure was significant (F ST = 0.108***) when demes included clonal replicates; however, when these clones were removed from the analysis, the sexual individuals comprised a metapopulation panmixia (F ST = 0.0007 NS). To further understand connectivity patterns, an assignment test was carried out which identified ten recent between-deme migrants with a mean dispersal distance of 116.6 km (± 80.5 SE). No long-distance dispersal was detected. These results highlight the ecological importance of the Bahía de La Paz region, including Archipiélago de Espíritu Santo MUMPA. This region, located at the center of the species peninsular range, exports larva to downstream sink demes such as the Loreto (northwardly) and Cabo Pulmo (southwardly) MUMPAs. Of importance, inter-MUMPA spacing was larger than the mean larval dispersal by ~56 km, suggesting thar the designation of intermediate 'no-take' zones would enhance short-distance connectivity. Conclusion: This study contributes as a baseline for policymakers and authorities to provide robust strategies for coral ecosystem protection and suggest that protection efforts must be increased towards peninsular intermediate reefs to promote metapopulation resilience from natural and anthropogenic factors.


Resumen Introducción: La estimación de la conectividad en corales escleractinios, como P. verrucosa, dentro de una red de áreas marinas protegidas (MPA) preestablecidas es fundamental para garantizar la efectividad en su conservación e incrementar su resiliencia. Objetivo: Determinar la estructura genética y la conectividad entre los demes de P. verrucosa dentro del Golfo de California, y evaluar el papel y efectividad de la red preestablecida de áreas marinas protegidas. Métodos: Se evaluó la conectividad de P. verrucosa en cinco locaciones a lo largo del golfo incluyendo tres MPA usando seis marcadores microsatélites. Resultados: Se demostró que existe estructura poblacional adjudicada a la presencia local y heterogénea de individuos clones (F ST = 0.108***); pero al removerlos del análisis, los individuos de origen sexual conformaron una metapoblación en panmixia (F ST = 0.0007 NS). Así mismo, se identificaron 10 potenciales migrantes en la región con una dispersión promedio de 116.57 km (± 80.47 SE) y sin conexión entre localidades extremas. De relevancia, se identificó la importancia ecológica del área central o Bahía de La Paz y MPA Archipiélago Espíritu Santo, como fuente larvaria de corales a toda la región. Además, se determinó que el espacio inter-MPA fue mayor que la distancia de dispersión promedio larvaria mencionada, por lo que sería de importancia ecológica el establecimiento de MPAs intermedias que favorezcan la conectividad a distancias cortas. Conclusiones: Los resultados encontrados en el estudio son pertinentes y contribuyen como línea base para los tomadores de decisiones y autoridades, proporcionando la conectividad de la región para establecer las estrategias de protección apropiadas, sugiriendo aumentar la conservación de las subpoblaciones centrales, la cuales promueven la resiliencia metapoblacional de P. verrucosa ante factores ambientales y/o antropogénicos.


Subject(s)
Anthozoa/genetics , Marine Conservation Area
3.
Zootaxa ; 4816(2): zootaxa.4816.2.9, 2020 Jul 16.
Article in English | MEDLINE | ID: mdl-33055709

ABSTRACT

Morphological analysis and microscopic observations of the Porites baueri holotype and specimens of other Porites species from different sites of the Mexican Pacific, allowed confirmation that Porites baueri is subjective synonym of Porites lobata. The holotype of Porites baueri was collected in the Marías Islands in 1957, and described as a new species by Squires in 1959. Since then, this species was considered as endemic, which is due to the lack of other specimens or a review of the taxonomic characters until now. The Mexican Pacific marine fauna loses a valid reef coral species, currently at 34, but gains in taxonomic clarity by ending almost 60 years of controversy.


Subject(s)
Anthozoa , Animals , Mexico
4.
Rev. biol. trop ; Rev. biol. trop;68(1)mar. 2020.
Article in English | LILACS-Express | LILACS | ID: biblio-1507657

ABSTRACT

Introduction: Invasive species are considered the second cause of extinction of native species after habitat loss. The impacts of invasive species have serious economic implications since the presence of this type of species can result in a decrease in ecosystem services granted to humans. In marine systems, some human activities such as maritime transport and aquaculture have favored the dispersion of invasive species, especially those with commercial importance. This paper describes the potential distribution of the tiger shrimp, Penaeus monodon, an invasive species along the American Atlantic coast. Objective: To describe a potential distribution model of Penaeus monodon in the American Atlantic region and compare the environmental characteristics of this region with those of the Indo-Pacific original niche conditions. Methods: Using geographic and environmental data, we constructed and tested three models to determine the efficiency of MaxEnt v. 3.3 software in predicting new areas for the distribution of this invasive shrimp species. Geographic data were downloaded from such web sites as the Global Biodiversity Information Facility, the Ocean Biogeographic Information System, and the United States Geological Survey, as well from literature. Environmental data were downloaded from Bio-Oracle v2.0 data base. The three tested models were: 1) the first was created using only recordings of Penaeus monodon from the Indo-Pacific (its origin zone) and then projected to the Atlantic (native model); 2) the second was built using only recordings from the invaded area; the training and projection area of this model was the Atlantic (invasive model); 3) the third included recordings from both the Indo-Pacific and Atlantic regions, and the model was trained and projected jointly in both areas (complete model). We extracted the values of the three models for each tiger shrimp sightings in the invaded area; sightings with values ³ 0.5 were considered as valid prediction of occurrence of the species. Results: We found that the following variables explained 80 % of species distribution: phosphates from the ocean surface, coastal type, chlorophyll a, and maximum bottom temperature. In terms of the models' ability to predict the occurrences reported in the Atlantic, results were as follows: Native model had a prediction index of 40 %; Invasive model was able to predict 81 % of recordings; and complete model predicted 92 % of total occurrences reported in the invaded area. Conclusions: Our findings suggest that based on the complete model, the countries where the tiger shrimp could establish itself are Mexico and Cuba. Continuous monitoring and conservation actions are relevant in the countries where this species is currently established, as well of those countries with potential for invasions.


Introducción: Las especies invasoras son consideradas como la segunda causa de extinción de especies nativas después de la pérdida del hábitat. Los impactos de las especies invasivas tienen serias implicaciones económicas, ya que su presencia puede resultar en un decremento de los servicios ecosistémicos que benefician al hombre. En los sistemas marinos, algunas actividades humanas como el transporte marítimo y la acuicultura han favorecido la dispersión de especies invasivas, especialmente aquellas con importancia comercial. Este artículo describe la distribución potencial del camarón tigre, Penaeus monodon, una especie invasora a lo largo de la costa Atlántica Occidental. Objetivo: Describir un modelo de distribución potencial de Penaeus monodon en la región del Atlántico americano y comparar las características ambientales de esta región con las condiciones del nicho original del Indo-Pacífico. Metodología: Usando datos geográficos y ambientales, se generaron tres modelos para determinar la eficiencia del software MaxEnt v.3.3 en la predicción de nuevas áreas para la distribución de esta especie invasora. Los datos geográficos se descargaron de sitios web como el Fondo para la Información sobre la Biodiversidad Mundial, el Sistema de Información Biogeográfica del Océano y el Servicio Geológico de los Estados Unidos de América, así como de la literatura. Los datos ambientales fueron descargados de Bio-Oracle v2.0. Los tres modelos probados fueron: 1) registros de P. monodon de la región del Indo-Pacífico (zona de origen) y su proyección al Océano Atlántico (modelo nativo); 2) registros del área invadida, al utilizar el Océano Atlántico como área de entrenamiento y proyección del modelo (modelo invasivo); y 3) registros de las áreas Indo-Pacífico y Atlántico para capacitar y proyectar el modelo conjuntamente en ambas áreas (modelo completo). Extrajimos los valores de los tres modelos para cada avistamiento de camarones tigre en el área invadida; los avistamientos con valores ³ 0.5 fueron considerados como predicciones válidas de presencia de la especie. Resultados: Los resultados mostraron que las siguientes variables explicaron el 80 % de la distribución de la especie: fosfatos del fondo marino, tipo de costa, clorofila a y temperatura máxima del fondo. En términos de las capacidades de los modelos para predecir las presencias reportadas en el Atlántico, los resultados fueron los siguientes: modelo nativo, tuvo un índice de predicción del 40 %; modelo invasivo fue capaz de predecir el 81 % de los registros; y modelo completo predijo el 92 % de las ocurrencias totales reportadas en el área de invasión. Conclusiones: Se encontró que, con base en el modelo conjunto, los países donde el camarón tigre se podría establecer son México y Cuba. Esto sugiere que el monitoreo continuo y las acciones de conservación son relevantes en los países donde esta especie está actualmente establecida, así como en aquellos países con el potencial de ser invadidos.

5.
PLoS One ; 14(6): e0216723, 2019.
Article in English | MEDLINE | ID: mdl-31188836

ABSTRACT

Climate change, mismanaged resource extraction, and pollution are reshaping global marine ecosystems with direct consequences on human societies. Sustainable ocean development requires knowledge and data across disciplines, scales and knowledge types. Although several disciplines are generating large amounts of data on marine socio-ecological systems, such information is often underutilized due to fragmentation across institutions or stakeholders, limited standardization across scale, time or disciplines, and the fact that information is often not searchable within existing databases. Compiling metadata, the information which describes existing sets of data, is an effective tool that can address these challenges, particularly when metadata corresponding to multiple datasets can be combined to integrate, organize and classify multidisciplinary data. Here, using Mexico as a case study, we describe the compilation and analysis of a metadatabase of ocean knowledge that aims to improve access to information, facilitate multidisciplinary data sharing and integration, and foster collaboration among stakeholders. We also evaluate the knowledge trends and gaps for informing ocean management. Analysis of the metadatabase highlights that past and current research in Mexico focuses strongly on ecology and fisheries, with biological data more consistent over time and space compared to data on human dimensions. Regional imbalances in available information were also evident, with most available information corresponding to the Gulf of California, Campeche Bank and Caribbean and less available for the central and south Pacific and the western Gulf of Mexico. Despite existing knowledge gaps in Mexico and elsewhere, we argue that systematic efforts such as this can often reveal an abundance of information for decision-makers to develop policies that meet key commitments on ocean sustainability. Surmounting current cross-scale social and ecological challenges for sustainability requires transdisciplinary approaches. Metadatabases are critical tools to make efficient use of existing data, highlight and address strengths and deficiencies, and develop scenarios to inform policies for managing complex marine social-ecological systems.


Subject(s)
Aquatic Organisms , Conservation of Natural Resources/methods , Metadata , Climate Change , Ecosystem , Humans , Knowledge , Mexico , Oceans and Seas
6.
PeerJ ; 6: e4295, 2018.
Article in English | MEDLINE | ID: mdl-29472993

ABSTRACT

The fishery for octopus in Northwest Mexico has increased to over 2,000 tons annually, but to date the specific composition of the catch has been ignored. With at least three main species targeted by artisanal fisheries in the region with distinct life histories, the lack of basic biological information about the distribution, metapopulation size and structure of each species could impede effective fisheries management to avoid overexploitation. We tested if different life histories of three species of octopus could help predict observed patterns of genetic diversity, population dynamics, structure and connectivity and how this information could be relevant to the sustainable management of the fishery. We sequenced two mitochondrial genes and genotyped seven nuclear microsatellite loci to identify the distribution of each species in 20 locations from the Gulf of California and the west coast of the Baja California peninsula. We tested five hypotheses derived from population genetic theory based on differences in the fecundity and dispersal potential for each species. We discovered that Octopus bimaculoides with low fecundity and direct development (without a planktonic phase) had lower average effective population size and genetic diversity, but higher levels of kinship, population structure, and richness of private alleles, than the other two species. These features indicated limited dispersal and high local recruitment. In contrast, O. bimaculatus and O. hubbsorum with higher fecundity and planktonic phase as paralarvae had higher effective population size and genetic diversity, and overall lower kinship and population structure than O. bimaculoides. These observations supported higher levels of gene flow over a larger geographical scale. O. bimaculatus with the longest planktonic paralarval duration and therefore larger dispersal potential had differences in the calculated parameters possibly associated with increased connectivity. We propose O. bimaculoides is more susceptible to over exploitation of small, isolated populations and could have longer recovery times than the other two species. This species may benefit from distinct fishery management within each local population. O. bimaculatus and O. hubbsorum may benefit from fishery management that takes into account metapopulation structure over larger geographic scales and the directionality and magnitude of larval dispersal driven by ocean currents and population connectivity among individuals of each locality. The distribution of each species and variations in their reproductive phenology is also important to consider when establishing marine reserves or seasonal fishing closures.

7.
Rev. biol. trop ; Rev. biol. trop;65(1): 195-210, Jan.-Mar. 2017. tab, ilus
Article in Spanish | LILACS | ID: biblio-897535

ABSTRACT

ResumenLa pesca de ornamento es una actividad económicamente viable en países en desarrollo debido a que el acuarismo se ha convertido en un pasatiempo mundial. En México la pesca se ha dado desde los 80´s, especialmente en la Península de Baja California, pero no se tiene registro adecuado de la producción comercial, ni de la ganancia económica que se obtiene de la explotación del recurso. El objetivo de este estudio fue calcular el nivel máximo de captura permisible de las cinco especies de peces de ornato incluidas en la NOM-059-SEMARNAT 2010 (protegidas por mandato federal), y la ganancia neta que el recurso podría generar. Se realizaron censos (N= 1 610) en 21 localidades arrecifales del Pacifico mexicano y el Golfo de California, para estimar las densidades poblacionales de cada taxón; también se calculó su tasa de mortalidad natural (M) a partir de la talla máxima (L∞), constante de crecimiento (k) y la temperatura (C), y la captura máxima permisible a partir de M. Finalmente, con los precios que se pagan en playa a los pescadores se hizo una estimación del valor económico que posee cada localidad en una temporada de pesca dada, y dentro de una superficie de 220 hectáreas (representativa del tamaño promedio de la zona de captura asignada a una cooperativa en México). Los resultados indicaron que las localidades en las que la pesca de ornato tiene un mejor potencial económico son las Islas Encantadas, Bahía de los Ángeles y el Archipiélago San Lorenzo (todas en el estado de Baja California). Fuera del golfo (donde no hay pesca legal de ornato actualmente), la mayor rentabilidad potencial la presentan Islas Marietas (Jalisco), y las Islas Revillagigedo. La pesca de ornato puede ser una actividad viable en varias de las zonas analizadas del país, sin embargo, los montos potenciales que la captura representa no son suficientes como para sostener un grupo organizado que la practique; por ello, la pesca de ornato debe verse como una actividad comercial alternativa. Finalmente, para que ésta sea una pesquería rentable y sostenible, se recomienda hacer uso de regulaciones federales ya en existentes, que ayuden a controlar cuotas de captura.


Abstract:Ornamental fisheries are economically viable activities in developing countries due to the fact that aquaria have become a worldwide hobby. In Mexico, the fishery has been conducted since the 1980s, especially in the Baja California Peninsula, but nevertheless, there are no adequate records of commercial production, or about the economic gain due to the exploitation of the resource. The objective of this paper was to calculate the maximum allowable catch for the five ornamental fishes included in the NOM-059-SEMARNAT (protected by federal mandate), and the net monetary gain that the resource might generate. Censuses (N=1 610) were conducted in 21 reef sites of the Mexican Pacific and Gulf of California in order to estimate population density of each taxon; also, natural mortality rate (M) was calculated from maximum size (L∞), individual growth rate (k) and temperature (C), and the total allowable catch was estimated on the basis of M. Finally, considering the prices of the species paid to fishermen at the beach, an estimation of the economic value of a single fishing season for an area of 220 hectares (representative of the catch area assigned in average to a cooperative in Mexico) was produced. The results indicated that the areas with the best economic potential were Encantadas Islands, Los Angeles Bay, and San Lorenzo Archipelago (all in the state of Baja California). Outside of the gulf (where no legal ornamental fisheries exist) the potentially more rentable locations were Marietas Islands (Jalisco), and the Revillagigedo Islands. Aquarium fisheries may be a viable activity in several of the analyzed areas of the country, however, the potential gain that harvest represents is not enough to fully sustain an organized group that would perform it; for that reason the ornamental fishery should be seen as an alternative commercial activity. Finally, to guarantee this activity to be a rentable and sustainable fishery, we recommended that, the existing rules defined by the Mexican federal government should be applied to control the catch quotas. Rev. Biol. Trop. 65 (1): 195-210. Epub 2017 March 01.


Subject(s)
Animals , Conservation of Natural Resources/economics , Fisheries/economics , Fishes/physiology , Seasons , Species Specificity , Pacific Ocean , Population Density , Statistics, Nonparametric , Animal Distribution , Mexico
8.
Rev Biol Trop ; 65(1): 195-210, 2017 Mar.
Article in Spanish | MEDLINE | ID: mdl-29466638

ABSTRACT

Ornamental fisheries are economically viable activities in developing countries due to the fact that aquaria have become a worldwide hobby. In Mexico, the fishery has been conducted since the 1980s, especially in the Baja California Peninsula, but nevertheless, there are no adequate records of commercial production, or about the economic gain due to the exploitation of the resource. The objective of this paper was to calculate the maximum allowable catch for the five ornamental fishes included in the NOM-059-SEMARNAT (protected by federal mandate), and the net monetary gain that the resource might generate. Censuses (N=1 610) were conducted in 21 reef sites of the Mexican Pacific and Gulf of California in order to estimate population density of each taxon; also, natural mortality rate (M) was calculated from maximum size (L∞), individual growth rate (k) and temperature (C), and the total allowable catch was estimated on the basis of M. Finally, considering the prices of the species paid to fishermen at the beach, an estimation of the economic value of a single fishing season for an area of 220 hectares (representative of the catch area assigned in average to a cooperative in Mexico) was produced. The results indicated that the areas with the best economic potential were Encantadas Islands, Los Angeles Bay, and San Lorenzo Archipelago (all in the state of Baja California). Outside of the gulf (where no legal ornamental fisheries exist) the potentially more rentable locations were Marietas Islands (Jalisco), and the Revillagigedo Islands. Aquarium fisheries may be a viable activity in several of the analyzed areas of the country, however, the potential gain that harvest represents is not enough to fully sustain an organized group that would perform it; for that reason the ornamental fishery should be seen as an alternative commercial activity. Finally, to guarantee this activity to be a rentable and sustainable fishery, we recommended that, the existing rules defined by the Mexican federal government should be applied to control the catch quotas.


Subject(s)
Conservation of Natural Resources/economics , Fisheries/economics , Fishes/physiology , Animal Distribution , Animals , Mexico , Pacific Ocean , Population Density , Seasons , Species Specificity , Statistics, Nonparametric
10.
Zootaxa ; 4150(4): 436-66, 2016 Aug 15.
Article in English | MEDLINE | ID: mdl-27615683

ABSTRACT

This paper presents an updated checklist of cartilaginous and bony fishes from the Revillagigedo Archipelago reefs and nearby areas (Tropical Eastern Pacific). To compile this list, we gathered data from field surveys between 1994 and 2015, from an exhaustive literature review, and by consulting museum collections and databases. With these records we estimated the completeness of the local fish inventory using four non-parametric rarefaction methods. We report a total of 389 species in 102 families; 235 of these are reef fish that occur in the Eastern but also in the Central Pacific, and 13 species were identified as endemic to the archipelago. A non-parametric statistical model predicts that the expected number of reef fish present at Revillagigedo should be 244.3 ± 3.2 species, which is 9 species more than the observed richness, and this difference was statistically significant (p = 0.02). That predictive model estimates that about 96% of the total richness of reef fish from the archipelago is known. Comparisons of the completeness of the inventory at Revillagigedo to that reported for the fish fauna of the Eastern Pacific and worldwide, showed that the quality of the sampling effort is remarkably high, in spite of the geographic isolation of the archipelago.


Subject(s)
Aquatic Organisms/classification , Biodiversity , Coral Reefs , Fishes/classification , Animal Distribution , Animals , Mexico , Pacific Ocean
11.
Dis Aquat Organ ; 116(2): 121-31, 2015 Oct 16.
Article in English | MEDLINE | ID: mdl-26480915

ABSTRACT

Coral reefs rival rainforest in biodiversity, but are declining in part because of disease. Tissue loss lesions, a manifestation of disease, are present in dominant Pocillopora along the Pacific coast of Mexico. We characterized tissue loss in 7 species of Pocillopora from 9 locations (44 sites) spanning southern to northern Mexico. Corals were identified to species, and tissue loss lesions were photographed and classified as those explainable by predation and those that were unexplained. A focal predation study was done concurrently at 3 locations to confirm origin of explained lesions. Of 1054 cases of tissue loss in 7 species of corals, 84% were associated with predation (fish, snails, or seastar) and the remainder were unexplained. Types of tissue loss were not related to coral density; however there was significant geographic heterogeneity in type of lesion; one site in particular (Cabo Pulmo) had the highest prevalence of predator-induced tissue loss (mainly pufferfish predation). Crown-of-thorns starfish, pufferfish, and snails were the most common predators and preferred P. verrucosa, P. meandrina, and P. capitata, respectively. Of the 9 locations, 4 had unexplained tissue loss with prevalence ranging from 1 to 3% with no species predilection. Unexplained tissue loss was similar to white syndrome (WS) in morphology, indicating additional study is necessary to clarify the cause(s) of the lesions and the potential impacts to dominant corals along the Pacific coast of Mexico.


Subject(s)
Anthozoa/physiology , Fishes/physiology , Predatory Behavior , Snails/physiology , Starfish/physiology , Animals , Coral Reefs , Mexico , Pacific Ocean
12.
Rev. biol. trop ; Rev. biol. trop;63(supl.2): 221-232, Apr.-Jun. 2015. tab, graf
Article in Spanish | LILACS, SaludCR | ID: biblio-958170

ABSTRACT

Resumen Los estudios sobre los equinodermos de la costa del Pacifico de México se han enfocado en la taxonomía y biogeografía y hay escasos datos sobre ecología comunitaria o poblacional del grupo. En el presente trabajo analizamos los cambios estacionales de la densidad poblacional y la distribución espacial de cuatro especies de erizos regulares (Diadema mexicanum, Echinometra mathaei oblonga. Eucidaris thouarsii y Tripneustes depressus) en tres bahías de la Isla Socorro, Archipiélago de Revillagigedo, México. Las especie más abundante en la isla fue E. mathaei oblonga (3.96 + 0.83 ind m-2; promedio y error típico), seguida de D. mexicanum (2.13 + 0.59 ind m-2), T. depressus y E. thouarsii (entre 0.50 y 0.11 ind m-2, respectivamente). La Bahía Binners tuvo la mayor densidad con 15.98 + 0.43 ind m-2, en gran medida debido a la alta incidencia de E. mathaei oblonga en el sitio. Estacionalmente, T. depressus y E. thouarsii no variaron significativamente su abundancia durante el año, pero D. mexicanum fue más abundante en invierno-primavera, y E. mathaei oblonga en el otoño. En relación al patrón de distribución espacial, dos de las especies (D. mexicanum y E. mathaei oblonga) presentaron una distribución agregada a lo largo del año y en las tres localidades de estudio, pero los otros dos equinoideos se dispusieron de forma azarosa. Hay varias razones para explicar el comportamiento de agregación en erizos de mar, pero para el caso de Isla Socorro aquí se argumenta a favor de que es un modo de defensa contra los abundantes peces depredadores que habitan los arrecifes. En contraste, las especies que no muestran agrupaciones residen en refugios durante el día (E. thouarsii) o bien su morfología y tamaño dificultan su captura por los peces (T. depressus).


Abstract The studies on echinoderms of the Mexican Pacific have focused on taxonomy and biogeography, and there are limited data on their ecology. We used transect to study Diadema mexicanum, Echinometra mathaei oblonga, Eucidaris thouarsii and Tripneustes depressus at three bays in Socorro Island, Revillagigedo Archipelago, Mexico (1989 and 1990). The most abundant species in the island was E. mathaei oblonga (3.96 + 0.83 ind m-2; average and standard error), followed by D. mexicanum (2.13 + 0.59 ind m-2), T. depressus and E. thouarsii (between 0.50 and 0.11 ind m-2, respectively). Binners Bay had the highest density with 15.98 + 0.43 ind m-2, mostly due to the high incidence of E. mathaei oblonga at the site. Seasonally, T. depressus and E. thouarsii did not significantly varied its abundance during the year, while D. mexicanum was more abundant in winter-spring, and E. mathaei oblonga in the fall. Two species (D. mexicanum and E. mathaei oblonga) had an aggregated distribution along the year and in the three study locations, but the other two echinoids followed a random distribution. This may be a defense against the abundant predatory fishes. In contrast, the species that do not aggregate inhabit in refuges during the day (E. thouarsii), or their shape and size makes them difficult to capture by fishes (T. depressus). Rev. Biol. Trop. 63 (Suppl. 2): 221-232. Epub 2015 June 01.


Subject(s)
Animals , Sea Urchins/growth & development , Population Density , Mexico
13.
Rev. biol. trop ; Rev. biol. trop;63(supl.2): 135-157, Apr.-Jun. 2015. tab, graf
Article in Spanish | LILACS, SaludCR | ID: biblio-958164

ABSTRACT

Resumen En esta revisión se presenta el estado de conocimiento de Diadema mexicanum en el Pacífico Tropical Oriental con base en estudios realizados principalmente en Panamá, Costa Rica y México. La densidad de D. mexicanum es baja, con valores entre 0.008 y 9.5 ind m-2, sin embargo, bajo condiciones particulares como la presencia de El Niño, las densidades pueden alcanzar hasta 150 ind m-2, por otra parte se ha reportado solo un evento de mortandad masiva a nivel local de esta especie en México. La bioerosión de D. mexicanum es más marcada en arrecifes más sureños, mientras que en localidades de México existen valores más bajos. De acuerdo con los estudios realizados en Panamá y México se ha determinado que D. mexicanum se reproduce entre abril y noviembre y su reproducción está influenciada por la dinámica oceánica de vientos y corrientes. Hace falta ampliar las áreas de estudio para determinar si las poblaciones de D. mexicanum siguen el mismo comportamiento reproductivo en toda su distribución geográfica. Finalmente, hace falta cuantificar el grado en que esta especie es afectada por extracción con distintos fines, e identificar c las medidas que se deben tomar para proteger a sus poblaciones.


Abstract Diadematids are among the most ecologically important sea urchin families. This review presents the state of knowledge of an important member of that family, Diadema mexicanum, in the Tropical Eastern Pacific based on studies carried out mainly in Panama, Costa Rica and Mexico. Density of D. mexicanum is low, fluctuating between 0.008 and 9.5 ind m-2, however under particular conditions such as El Niño, densities reach up to 150 ind m-2. On the other hand, just one event of mass mortality at a local level has been reported for this species in Mexico. Bioerosion caused by D. mexicanum is more intense in southern reefs, whereas in localities from Mexico values are lower. According to studies carried out in Panama and Mexico it has been determined that D. mexicanum reproduces between April and November and its reproduction is influenced by ocean dynamics of winds and currents. It is necessary to extend the study areas in order to determine if populations of D. mexicanum have a similar behavior along its entire geographical distribution. Finally, it is necessary to assess the effect of extraction for different purposes on this species and identify the actions that should be taken in order to protect its populations. Rev. Biol. Trop. 63 (Suppl. 2): 135-157. Epub 2015 June 01.


Subject(s)
Animals , Reproduction , Sea Urchins/classification , Echinodermata/anatomy & histology , Diet, Food, and Nutrition , Mexico
14.
Ecol Evol ; 3(12): 4070-91, 2013 Oct.
Article in English | MEDLINE | ID: mdl-24324860

ABSTRACT

The coral fauna of the Eastern Tropical Pacific (ETP) is depauperate and peripheral; hence, it has drawn attention to the factors allowing its survival. Here, we use a genetic seascape approach and ecological niche modeling to unravel the environmental factors correlating with the genetic variation of Porites panamensis, a hermatypic coral endemic to the ETP. Specifically, we test if levels of diversity and connectivity are higher among abundant than among depauperate populations, as expected by a geographically relaxed version of the Abundant Center Hypothesis (rel-ACH). Unlike the original ACH, referring to a geographical center of distribution of maximal abundance, the rel-ACH refers only to a center of maximum abundance, irrespective of its geographic position. The patterns of relative abundance of P. panamensis in the Mexican Pacific revealed that northern populations from Baja California represent its center of abundance; and southern depauperate populations along the continental margin are peripheral relative to it. Genetic patterns of diversity and structure of nuclear DNA sequences (ribosomal DNA and a single copy open reading frame) and five alloenzymatic loci partially agreed with rel-ACH predictions. We found higher diversity levels in peninsular populations and significant differentiation between peninsular and continental colonies. In addition, continental populations showed higher levels of differentiation and lower connectivity than peninsular populations in the absence of isolation by distance in each region. Some discrepancies with model expectations may relate to the influence of significant habitat discontinuities in the face of limited dispersal potential. Environmental data analyses and niche modeling allowed us to identify temperature, water clarity, and substrate availability as the main factors correlating with patterns of abundance, genetic diversity, and structure, which may hold the key to the survival of P. panamensis in the face of widespread environmental degradation.

15.
Rev Biol Trop ; 61(2): 583-94, 2013 Jun.
Article in Spanish | MEDLINE | ID: mdl-23885577

ABSTRACT

Coral reefs in the Mexican Pacific and notably those of the continental coastline of Colima state are still poorly studied. Fortunately, recent efforts have been carried out by researchers from different Mexican institutions to fill up these information gaps. The aim of this study was to determine the ecological structure of the rich and undisturbed coral building communities of Carrizales by using the point transect interception method (25m-long). For this, three survey expeditions were conducted between June and October 2005 and September 2006; and for comparison purposes, the reef was subdivided according to its position in the bay, and depth (0 to 5 m, and 6 to 10 m). Thirteen coral species were observed in the area, with Pocillopora verrucosa as the most abundant, contributing up to 32.8% of total cover, followed by Porites panamensis and Pocillopora capitata with 11% and 7%, respectively. Other species, Pocillopora damicornis, Pavona gigantea, Pocillopora eydouxi and Pocillopora inflata accounted for 1.5% to 2% of coral cover whereas the remaining five species had cover of less than 1%. Seven of the observed species represented new records for Colima state coastline: Pocillopora eydouxi, P inflata, P meandrina, Pavona duerdeni, P varians, Psammocora stellata and P contigua. This last species is a relevant record, because it has never been observed before in the Eastern Pacific. Although there was no significant difference (ANOVA, p = 0.478) neither in the abundance between the sides of the bay, nor between the depths considered, and the shallow zone observed the higher coral cover. Live coral cover was up to 61%, one of the highest ever reported for the Mexican Pacific, including the Gulf of California. The observed values of diversity (H' = 0.44 +/- 0.02), uniformity (J' = 0.76 +/- 0.02), and taxonomic distinctness index (delta* = 45.87 +/- 3.16), showed that currently this is the most important coral reef of Colima coastline. Currently, this region does not show any disturbance effects, but the increasing economic development of Manzanillo, as one of the main commercial ports of Mexico, its proximity to the reef, and the burgeoning number of tourists, may have some ecosystem impacts, for which management and conservation plans for Colima coastline are highly recommended.


Subject(s)
Anthozoa/classification , Biodiversity , Coral Reefs , Animals , Environmental Monitoring/methods , Mexico , Population Density , Population Dynamics
16.
Rev. biol. trop ; Rev. biol. trop;61(2): 583-594, Jun. 2013. ilus, graf, tab
Article in Spanish | LILACS | ID: lil-675454

ABSTRACT

Coral reefs in the Mexican Pacific and notably those of the continental coastline of Colima state are still poorly studied. Fortunately, recent efforts have been carried out by researchers from different Mexican institutions to fill up these information gaps. The aim of this study was to determine the ecological structure of the rich and undisturbed coral building communities of Carrizales by using the point transect interception method (25m-long). For this, three survey expeditions were conducted between June and October 2005 and September 2006; and for comparison purposes, the reef was subdivided according to its position in the bay, and depth (0 to 5m, and 6 to 10m). Thirteen coral species were observed in the area, with Pocillopora verrucosa as the most abundant, contributing up to 32.8% of total cover, followed by Porites panamensis and Pocillopora capitata with 11% and 7%, respectively. Other species, Pocillopora damicornis, Pavona gigantea, Pocillopora eydouxi and Pocillopora inflata accounted for 1.5% to 2% of coral cover whereas the remaining five species had cover of less than 1%. Seven of the observed species represented new records for Colima state coast- line: Pocillopora eydouxi, P. inflata, P. meandrina, Pavona duerdeni, P. varians, Psammocora stellata and P. contigua. This last species is a relevant record, because it has never been observed before in the Eastern Pacific. Although there was no significant difference (ANOVA, p=0.478) neither in the abundance between the sides of the bay, nor between the depths considered, and the shallow zone observed the higher coral cover. Live coral cover was up to 61%, one of the highest ever reported for the Mexican Pacific, including the Gulf of California. The observed values of diversity (H´=0.44±0.02), uniformity (J´=0.76±0.02), and taxonomic distinctness index (Δ*=45.87±3.16), showed that currently this is the most important coral reef of Colima coastline. Currently, this region does not show any disturbance effects, but the increasing economic development of Manzanillo, as one of the main commercial ports of Mexico, its proximity to the reef, and the burgeoning number of tourists, may have some ecosystem impacts, for which management and conservation plans for Colima coastline are highly recommended.


El conocimiento ecológico de corales arrecifales en el Pacífico mexicano es escaso, por lo que el objetivo de este trabajo fue determinar la estructura de la comunidad de corales hermatípicos en el arrecife de Carrizales, Colima, mediante el uso de transectos y buceo autónomo (junio y octubre 2005, septiembre 2006). De las 13 especies de corales encontradas, Pocillopora verrucosa fue la más abundante y siete representan nuevos registros, sobresaliendo Psammocora contigua, primer registro para el Pacífico Oriental. No hubo diferencias significativas de abundancia entre profundidades, pero la zona somera presenta una mayor cobertura. Este sitio presenta una de las riquezas y cobertura de coral más alta (61%) en el Pacífico Mexicano y valores de diversidad (H´=0.44±0.02), uniformidad (J´=0.76±0.02), y de diferenciación taxonómica (Δ*=45.87±3.16) relativamente altos. Actualmente la región no presenta grandes perturbaciones pero el creciente desarrollo económico de Manzanillo, uno de los principales puertos comerciales del país, además del creciente número de turistas, podrían afectar al arrecife, por lo que se sugiere implementar medidas de protección con el fin de mantener al arrecife más importante del litoral de Colima.


Subject(s)
Animals , Anthozoa/classification , Biodiversity , Coral Reefs , Environmental Monitoring/methods , Mexico , Population Density , Population Dynamics
17.
Zootaxa ; 3609: 451-64, 2013 Feb 01.
Article in English | MEDLINE | ID: mdl-24699609

ABSTRACT

Our study provides a checklist of 36 crustacean decapods from the Mexican tropical Pacific coastline. Most of the species were previously recorded from coral communities in the Gulf of California. Data were obtained by visual censuses of coral communities and some specimens were collected by extractions of coral branches (approximately eight liters of coral volume). We found new geographic records for three species from the Eastern Pacific and seven species that have extended ranges into Mexican waters. Only one species is documented with a northerly range from Central America to Mexican waters.


Subject(s)
Decapoda/classification , Decapoda/physiology , Animals , Anthozoa , Ecosystem , Female , Male , Mexico , Pacific Ocean , Symbiosis
18.
Rev. biol. trop ; Rev. biol. trop;60(supl.2): 121-132, abr. 2012. ilus, graf, mapas, tab
Article in English | LILACS, SaludCR | ID: lil-657839

ABSTRACT

The 1982-83 El Niño event produced a high coral mortality (50-90%) in several localities in the Eastern Tropical Pacific, which resulted in an outbreak of the sea urchin populations of Diadema mexicanum A. Agassiz, 1863 in some reefs, leading to an increase in coral framework bioerosion. In Costa Rica, El Niño impact varied among three of the most important coral reefs localities, being higher in Cocos Island, moderate in Caño Island, and lower in Culebra Bay; D. mexicanum densities followed the same pattern. To understand the historic role of this sea urchin on the balance between bioerosion and bioacretion, we made a reconstruction of bioerosion impact based on current patterns of carbonate ingestion by the sea urchins, growth rates and skeletal density of the main coral builders, and historical information of sea urchin population density and coral cover. The reconstruction model varied depending on locality. At Cocos Island, the effect on the reef carbonate budget ranged from negative to positive, improving coral recruitment and the recovery of the reef. At Caño Island, there was no apparent effect. In Culebra Bay, the effects ranged from a positive-neutral effect to a negative one, the latter possibly associated with an increase of eutrophic conditions that facilitated bioerosion of the coral framework. The importance of this sea urchin in reef dynamics varies with amount of reef protection, overfishing, and coastal management, and it has a large influence on the carbonate balances of the Pacific Costa Rican coral reefs.


El fenómeno de El Niño de 1982-83 produjo una alta mortalidad coralina (50-90%) en varias localidades del Pacífico Tropical Oriental, lo que en algunos arrecifes trajo como consecuencia una explosión en la poblaciones de erizos de mar, Diadema mexicanum, y por consiguiente un aumento en la bioerosión del basamento coralino. En Costa Rica, el impacto fue diferencial en tres localidades arrecifales, siendo mayor en la Isla del Coco, intermedio en la Isla del Caño, y menor en Bahía Culebra, con similares patrones en la presencia del erizo D. mexicanum. Con el fin de poder entender el papel histórico que desempeña este erizo de mar en el balance entre bioerosión y bioacreción, se reconstruyó el impacto bioerosivo basándose en patrones actuales de ingestión de carbonatos por parte del erizo, tasas de crecimiento y densidad del esqueleto coralino, y datos históricos de densidad poblacional del erizo y cobertura coralina. Los resultados de las reconstrucciones variaron dependiendo de la localidad. En la Isla del Coco, el efecto de los erizos de mar varío de un efecto negativo sobre el balance arrecifal de carbonatos a un efecto positivo, favoreciendo el reclutamiento coralino y la recuperación del arrecife. En la Isla del Caño, Diadema presentó un efecto neutro, al no tener una participación preponderante en el balance de carbonatos de esta isla. Mientras, que en Bahía Culebra, los efectos de los erizos de mar pasaron de tener un efecto positivo-neutro, a uno negativo, posiblemente asociado a un incremento en condiciones eutróficas de la bahía que están favoreciendo un incremento en la bioerosión del basamento coralino. El valor de este erizo en la dinámica arrecifal y su relación con la protección, sobrepesca, y manejo costero, posee una gran influencia en el balance de carbonatos en los arrecifes coralinos del Pacífico de Costa Rica.


Subject(s)
Sea Urchins/classification , Climate Change/classification , Coral Reefs , Costa Rica
19.
Rev Biol Trop ; 59(2): 871-85, 2011 Jun.
Article in Spanish | MEDLINE | ID: mdl-21721244

ABSTRACT

The uses of biological indicators allow to save time, resources and staff efforts when monitoring programs are conducted. The reef fishes are among the species with biggest potential as indicators since they are conspicuous, easy to identify in the field and have ecological and economical importance. The objective of this study was to evaluate the usefulness of higher taxa to predict fish ecological indices in Cabo Pulmo reef. We generated multiple stepwise regression equations with species abundance data grouped at genera and family levels as factors, and using ecological indices (H', J', delta*) as dependent variables. To test the efficiency of the models, the expected indexes were compared with those observed in the field during independent test surveys. Results showed that all models were highly significant, and the best fit occurred at genus level to H', while those used for delta*, based on family data level, were less precise. The proportion of variables required to apply prediction models of any ecological index never exceeded 41% of the total taxa (genera or families). In conclusion, the use of regression methods to determine higher taxa indicators is adequate and represents a good potential to be used in monitoring programs. In addition, the use of genera and families as indicators provide logistic benefits as training for monitors is less intense and expensive. Finally, the use of expected-observed comparisons to measure the quality of the evaluations can be useful for managers in order to interpret and communicate results of the scientific endeavors to the society, so they in turn can participate and help to improve and facilitate long-term monitoring at Cabo Pulmo National Park.


Subject(s)
Biodiversity , Environmental Monitoring/methods , Fishes/classification , Animals , Mexico , Multivariate Analysis
20.
Rev. biol. trop ; Rev. biol. trop;59(2): 871-885, jun. 2011. graf, tab
Article in Spanish | LILACS | ID: lil-638126

ABSTRACT

Ichthyofauna monitoring using higher taxa in Cabo Pulmo National Park, México. The uses of biological indicators allow to save time, resources and staff efforts when monitoring programs are conducted. The reef fishes are among the species with biggest potential as indicators since they are conspicuous, easy to identify in the field and have ecological and economical importance. The objective of this study was to evaluate the usefulness of higher taxa to predict fish ecological indices in Cabo Pulmo reef. We generated multiple stepwise regression equations with species abundance data grouped at genera and family levels as factors, and using ecological indices (H´, J´, Δ*) as dependent variables. To test the efficiency of the models, the expected indexes were compared with those observed in the field during independent test surveys. Results showed that all models were highly significant, and the best fit occurred at genus level to H´, while those used for Δ*, based on family data level, were less precise. The proportion of variables required to apply prediction models of any ecological index never exceeded 41% of the total taxa (genera or families). In conclusion, the use of regression methods to determine higher taxa indicators is adequate and represents a good potential to be used in monitoring programs. In addition, the use of genera and families as indicators provide logistic benefits as training for monitors is less intense and expensive. Finally, the use of expected-observed comparisons to measure the quality of the evaluations can be useful for managers in order to interpret and communicate results of the scientific endeavors to the society, so they in turn can participate and help to improve and facilitate long-term monitoring at Cabo Pulmo National Park. Rev. Biol. Trop. 59 (2): 871-885. Epub 2011 June 01.


El uso de indicadores biológicos es una herramienta útil para la descripción de las comunidades y permite ahorrar recursos en programas de monitoreo. Con el fin de evaluar el potencial bioindicador de grupos taxonómicos superiores en el Parque Nacional Cabo Pulmo, México, se construyeron modelos de regresión múltiple por pasos con valores de abundancia agrupados a nivel género y familia como predictores, mediante el uso de variables dependientes, los índices ecológicos de diversidad (H’), equidad (J’) y distintividad taxonómica (Δ*). Posteriormente se compararon los resultados de los modelos contra los valores de los índices ecológicos observados en un muestreo independiente. Los resultados mostraron que todos los modelos fueron altamente significativos; los valores más altos del coeficiente de determinación se obtuvieron en las regresiones aplicadas a H’, mientras que las usadas por Δ* fueron las menos precisas. Los resultados sugieren que los modelos predictivos aquí generados son susceptibles de ser aplicados en un programa de monitoreo. Este estudio sugiere la implementación de un programa de monitoreo a largo plazo basado en bioindicadores de la estructura comunitaria de peces en el Parque Nacional Cabo Pulmo, el cual combine la precisión con la facilidad de obtención de datos.


Subject(s)
Animals , Biodiversity , Environmental Monitoring/methods , Fishes/classification , Mexico , Multivariate Analysis
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