Mexico is home to a large number of reptile species and has one of the greatest diversities of ve... more Mexico is home to a large number of reptile species and has one of the greatest diversities of venomous snakes, among which the rattlesnakes pertaining to the Crotalus genus stand out. Out of more than 40 species in the country, nine are found in Zacatecas: C. aquilus, C. atrox, C. basiliscus, C. lepidus, C. molossus, C. polystictus, C. pricei, C. scutulatus and C. willardi. Although these reptiles are important, due to their relevance in terms of ecology, cultural use and public health, their conservation is impacted by multiple factors, such as habitat fragmentation and indiscriminate killing. Thus, most species within this genus are found in some type of risk category at both the national and international level. The purpose of this study was to determine the potential distribution and diversity of rattlesnakes at the municipal level in the understudied state of Zacatecas. To do this, we analyzed and described the global distribution of nine rattlesnake species by building specie...
Invasive alien species are one of most severe threats to biodiversity and natural resources. Thes... more Invasive alien species are one of most severe threats to biodiversity and natural resources. These biological invasions have been studied from the niche conservatism and niche shifts perspective. Niche differentiation may result from changes in fundamental niche or realized niche or both; in biological invasions, niche differences between native and non-native ranges can appear through niche expansion, niche unfilling and niche stability. The American bullfrog Lithobates catesbeianus is an invasive species that can have negative impacts on native amphibian populations. This research examines the climate niche shifts of this frog, its potential range of expansion in Mexico and the risk of invasion by bullfrog in the habitats of 82 frog species endemic to Mexico, that based on their climatic niche similarity were divided in four ecological groups. The results indicate that species in two ecological groups were the most vulnerable to invasion by bullfrog. However, the climate niche shi...
Las cactáceas en México son un grupo representativo de las zonas áridas que actualmente presenta ... more Las cactáceas en México son un grupo representativo de las zonas áridas que actualmente presenta problemas de conservación debido a la sobreexplotación y el saqueo de los que han sido objeto en todo el país. En este trabajo se reporta la distribución actual de tres especies de cactáceas en el estado de Aguascalientes actualmente sujetas a protección especial según la legislación ambiental federal mexicana (Ferocactus histrix, Mammillaria bombycina y M. perezdelarosae). Se estimó su distribución potencial mediante la técnica de modelado de nicho ecológico. La mayoría de las poblaciones de F. histrix se encontraron en la mitad oeste del estado de Aguascalientes, entre 1750 y 2473 m s.n.m., en cañadas de difícil acceso o en laderas con poca inclinación. Las de M. bombycina fueron encontradas en la parte suroeste del de la entidad, entre 1847 y 2417 m de altitud, en colonias en paredes de cañadas o a ras del suelo cerca de las cañadas. Por último, las de M. perezdelarosae se ubicaron en...
Se presentan medidas preventivas contra la mordedura de estos serpientess, cuestiones básicas de ... more Se presentan medidas preventivas contra la mordedura de estos serpientess, cuestiones básicas de primeros auxilios, y elementos de características en los diversos tipos de especies en el estado de Aguascalientes.
The Baja California Peninsula has over 250 islands and islets with many endemic species. Among th... more The Baja California Peninsula has over 250 islands and islets with many endemic species. Among them, rattlesnakes are the most numerous but also one of the least studied groups. The study of island rattlesnake venom could guide us to a better understanding of evolutionary processes and the description of novel toxins. Crotalus helleri caliginis venom samples were analyzed to determine possible ontogenetic variation with SDS-PAGE in one and two dimensions and with RP-HPLC. Western Blot, ELISA, and amino-terminal sequencing were used to determine the main components of the venom. The biological and biochemical activities demonstrate the similarity of C. helleri caliginis venom to the continental species C. helleri helleri, with both having low proteolytic and phospholipase A2 (PLA2) activity but differing due to the absence of neurotoxin (crotoxin-like) in the insular species. The main components of the snake venom were metalloproteases, serine proteases, and crotamine, which was the most abundant toxin group (30–35% of full venom). The crotamine was isolated using size-exclusion chromatography where its functional effects were tested on mouse phrenic nerve–hemidiaphragm preparations in which a significant reduction in muscle twitch contractions were observed. The two Mexican antivenoms could neutralize the lethality of C. helleri caliginis venom but not the crotamine effects.
Revisión del conflicto entre los humanos y las serpientes en México: origen, mitigación y perspectivas, 2021
Review of the human-snake conflict in Mexico: origin, mitigation and perspectives. The conflict b... more Review of the human-snake conflict in Mexico: origin, mitigation and perspectives. The conflict between humans and snakes has existed since unmemorable times. Fear of and aversion towards these animals may have an evolutionary explanation and may be justified because venomous and deadly snakes cause thousands of deaths around the world each year. Furthermore, social perception, the media, myths, and even religion, increase and feed this fear, resulting in the intentional slaughter of snakes being a common practice in many places. As Mexico is a mega-diverse country with more species of snakes than any other country, it faces a particularly difficult situation with regard to snake bites. Here we revise this human-snake conflict from different perspectives in order to better understand it, to propose possible solutions to reduce it, and to contribute towards snake conservation.
ZooKeys: A peer-reviewed open-access journal, 2020
Mexico is home to a large number of reptile species and has one of the greatest diversities of ve... more Mexico is home to a large number of reptile species and has one of the greatest diversities of venomous snakes, among which the rattlesnakes pertaining to the Crotalus genus stand out. Out of more than 40 species in the country, nine are found in Zacatecas: C. aquilus, C. atrox, C. basiliscus, C. lepidus, C. mo-lossus, C. polystictus, C. pricei, C. scutulatus and C. willardi. Although these reptiles are important, due to their relevance in terms of ecology, cultural use and public health, their conservation is impacted by multiple factors, such as habitat fragmentation and indiscriminate killing. Thus, most species within this genus are found in some type of risk category at both the national and international level. The purpose of this study was to determine the potential distribution and diversity of rattlesnakes at the municipal level in the understudied state of Zacatecas. To do this, we analyzed and described the global distribution of nine rattlesnake species by building species distribution models, which determined their potential distri
Resumen la familia Asteraceae es el grupo con más especies de angiospermas a nivel mundial (entre... more Resumen la familia Asteraceae es el grupo con más especies de angiospermas a nivel mundial (entre 24,000-33,000). A pesar de su diversidad, no se cuenta con suficiente información sobre la riqueza y distribución del grupo para su conservación en el centro de México. el uso de métodos no paramétricos para medir la diversidad de Asteraceae permitirá obtener información para promover su conservación en algunas áreas del centro de México. especies de la familia Asteraceae localizadas en el centro de México. cuatro áreas prioritarias para la conservación sobre todo del estado de Aguascalientes: Sierra Fría, Sierra del Laurel, Tepezalá-Asientos y Juan El Grande (2016-2019). se utilizaron los métodos no paramétricos ICE y Chao2 para estimar la riqueza; se obtuvo una curva de acumulación de especies. Asimismo, se elaboró un mapa de riqueza de especies en una cuadrícula de 5 × 5 km para identificar cuadrantes con riqueza alta. Se calculó la β-diversidad para medir diferencias en composición, anidamiento y recambio de especies entre áreas. los estimadores ICE y Chao2 indican una sobreestimación de la riqueza observada. El grado de completitud del inventario florístico de la familia en las áreas es de 62 % para ICE y de 64 % para Chao2. La β-diversidad indica alto recambio y pérdida de especies entre áreas. la riqueza y β-diversidad obtenidas son resultado del patrón espacial agrupado de las especies, presencia de especies exclusivas por área y preferencias y propiedades ecológicas específicas del grupo. Aguascalientes, β-diversidad, Chao2, Curva de acumulación de especies, Estimador de cobertura basado en incidencia. Abstract The Asteraceae is the family with the highest number of angiosperm species (24,000-33,000). Despite this diversity, information on richness and distribution of the group for conservation purposes in central Mexico is scarce. The use of non-parametric methods to measure Asteraceae species diversity will allow to obtain information to promote the conservation of some areas in central Mexico. Species of the Asteraceae in four priority conservation areas in central Mexico. Four priority conservation areas mainly located in the state of Aguascalientes: Sierra Fría, Sierra del Laurel, Tepezalá-Asientos, and Juan El Grande (2016 to 2019). Non-parametric methods ICE and Chao2 to estimate species richness were employed and a species accumulation curve was obtained. A species richness map was made in a 5 × 5 km grid to identify quadrants with high species richness. β-diversity was calculated to measure differences in composition, nesting, and species turnover among areas. ICE and Chao2 estimators indicate an overestimation of the observed species richness. The degree of completeness of the floristic inventory for Asteraceae in the study areas is 62 % for ICE and 64 % for Chao2. β-diversity indicates high turnover and species lost among areas. Richness and β-diversity obtained are the result of the species grouping spatial pattern, presence of exclusive species by area, and the ecological properties and preferences of the group. Aguascalientes, β-diversity, Chao2, Incidence-based coverage estimator, Species accumulation curve. Antecedentes: Hipótesis: Especies de estudio: Sitio y años de estudio: Métodos: Resultados: Conclusiones: Palabras clave: Background:
Invasive alien species are one of most severe threats to biodiversity and natural resources. Thes... more Invasive alien species are one of most severe threats to biodiversity and natural resources. These biological invasions have been studied from the niche conservatism and niche shifts perspective. Niche differentiation may result from changes in fundamental niche or realized niche or both; in biological invasions, niche differences between native and non-native ranges can appear through niche expansion, niche unfilling and niche stability. The Ameri-can bullfrog Lithobates catesbeianus is an invasive species that can have negative impacts on native amphibian populations. This research examines the climate niche shifts of this frog, its potential range of expansion in Mexico and the risk of invasion by bullfrog in the habitats of 82 frog species endemic to Mexico, that based on their climatic niche similarity were divided in four ecological groups. The results indicate that species in two ecological groups were the most vulnerable to invasion by bullfrog. However, the climate niche shifts of L. catesbeianus may allow it to adapt to new environmental conditions, so species from the two remaining groups cannot be dismissed as not vulnerable. This information is valuable for decision making in prioritizing areas for conservation of Mexican endemic frogs.
Invasive alien species are one of most severe threats to biodiversity and natural resources. Thes... more Invasive alien species are one of most severe threats to biodiversity and natural resources. These biological invasions have been studied from the niche conservatism and niche shifts perspective. Niche differentiation may result from changes in fundamental niche or realized niche or both; in biological invasions, niche differences between native and non-native ranges can appear through niche expansion, niche unfilling and niche stability. The Ameri-can bullfrog Lithobates catesbeianus is an invasive species that can have negative impacts on native amphibian populations. This research examines the climate niche shifts of this frog, its potential range of expansion in Mexico and the risk of invasion by bullfrog in the habitats of 82 frog species endemic to Mexico, that based on their climatic niche similarity were divided in four ecological groups. The results indicate that species in two ecological groups were the most vulnerable to invasion by bullfrog. However, the climate niche shifts of L. catesbeianus may allow it to adapt to new environmental conditions, so species from the two remaining groups cannot be dismissed as not vulnerable. This information is valuable for decision making in prioritizing areas for conservation of Mexican endemic frogs.
Invasive alien species are one of most severe threats to biodiversity and natural resources. Thes... more Invasive alien species are one of most severe threats to biodiversity and natural resources. These biological invasions have been studied from the niche conservatism and niche shifts perspective. Niche differentiation may result from changes in fundamental niche or realized niche or both; in biological invasions, niche differences between native and non-native ranges can appear through niche expansion, niche unfilling and niche stability. The Ameri-can bullfrog Lithobates catesbeianus is an invasive species that can have negative impacts on native amphibian populations. This research examines the climate niche shifts of this frog, its potential range of expansion in Mexico and the risk of invasion by bullfrog in the habitats of 82 frog species endemic to Mexico, that based on their climatic niche similarity were divided in four ecological groups. The results indicate that species in two ecological groups were the most vulnerable to invasion by bullfrog. However, the climate niche shifts of L. catesbeianus may allow it to adapt to new environmental conditions, so species from the two remaining groups cannot be dismissed as not vulnerable. This information is valuable for decision making in prioritizing areas for conservation of Mexican endemic frogs.
Vipers are among the most misunderstood and persecuted animals. They occupy most terrestrial ecos... more Vipers are among the most misunderstood and persecuted animals. They occupy most terrestrial ecosystems around the world, often at high population densities. However, certain aspects of their biology (e.g., low fecundity and slow growth) have resulted in vipers being disproportionately threatened by extinction. Despite increased extinction risk, relatively little is known about viper biology, severely limiting the development and implementation of conservation initiatives. Here, we review the conservation status of vipers globally, map species richness, and develop three indices (one reactive; one proactive; one combined index emphasising irreplaceable species facing severe threats) to identify species for which conservation action should be prioritised. Moreover, we map species richness weighted by each index to identify regions for conservation prioritisation. We ranked prioritisation scores for all species for which data were available. In doing so we identify species for which valuable data are missing and that should be prioritised for research. We additionally show that 17 species, currently listed as Not Assessed or Data Deficient by the IUCN, score sufficiently high on our Threat Index to be considered as Threatened in the future. We identify multiple regions for which viper conservation action should be prioritised. These areas broadly correlate with species richness patterns, suggesting that species richness may be an effective proxy for conservation planning. Finally, we discuss the major gaps in knowledge, as well as the major threats facing vipers.
Vipers are among the most misunderstood and persecuted animals. They occupy most terrestrial ecos... more Vipers are among the most misunderstood and persecuted animals. They occupy most terrestrial ecosystems around the world, often at high population densities. However, certain aspects of their biology (e.g., low fecundity and slow growth) have resulted in vipers being disproportionately threatened by extinction. Despite increased extinction risk, relatively little is known about viper biology, severely limiting the development and implementation of conservation initiatives. Here, we review the conservation status of vipers globally, map species richness, and develop three indices (one reactive; one proactive; one combined index emphasising irreplaceable species facing severe threats) to identify species for which conservation action should be prioritised. Moreover, we map species richness weighted by each index to identify regions for conservation prioritisation. We ranked prioritisation scores for all species for which data were available. In doing so we identify species for which valuable data are missing and that should be prioritised for research. We additionally show that 17 species, currently listed as Not Assessed or Data Deficient by the IUCN, score sufficiently high on our Threat Index to be considered as Threatened in the future. We identify multiple regions for which viper conservation action should be prioritised. These areas broadly correlate with species richness patterns, suggesting that species richness may be an effective proxy for conservation planning. Finally, we discuss the major gaps in knowledge, as well as the major threats facing vipers.
Mexico is home to a large number of reptile species and has one of the greatest diversities of ve... more Mexico is home to a large number of reptile species and has one of the greatest diversities of venomous snakes, among which the rattlesnakes pertaining to the Crotalus genus stand out. Out of more than 40 species in the country, nine are found in Zacatecas: C. aquilus, C. atrox, C. basiliscus, C. lepidus, C. molossus, C. polystictus, C. pricei, C. scutulatus and C. willardi. Although these reptiles are important, due to their relevance in terms of ecology, cultural use and public health, their conservation is impacted by multiple factors, such as habitat fragmentation and indiscriminate killing. Thus, most species within this genus are found in some type of risk category at both the national and international level. The purpose of this study was to determine the potential distribution and diversity of rattlesnakes at the municipal level in the understudied state of Zacatecas. To do this, we analyzed and described the global distribution of nine rattlesnake species by building specie...
Invasive alien species are one of most severe threats to biodiversity and natural resources. Thes... more Invasive alien species are one of most severe threats to biodiversity and natural resources. These biological invasions have been studied from the niche conservatism and niche shifts perspective. Niche differentiation may result from changes in fundamental niche or realized niche or both; in biological invasions, niche differences between native and non-native ranges can appear through niche expansion, niche unfilling and niche stability. The American bullfrog Lithobates catesbeianus is an invasive species that can have negative impacts on native amphibian populations. This research examines the climate niche shifts of this frog, its potential range of expansion in Mexico and the risk of invasion by bullfrog in the habitats of 82 frog species endemic to Mexico, that based on their climatic niche similarity were divided in four ecological groups. The results indicate that species in two ecological groups were the most vulnerable to invasion by bullfrog. However, the climate niche shi...
Las cactáceas en México son un grupo representativo de las zonas áridas que actualmente presenta ... more Las cactáceas en México son un grupo representativo de las zonas áridas que actualmente presenta problemas de conservación debido a la sobreexplotación y el saqueo de los que han sido objeto en todo el país. En este trabajo se reporta la distribución actual de tres especies de cactáceas en el estado de Aguascalientes actualmente sujetas a protección especial según la legislación ambiental federal mexicana (Ferocactus histrix, Mammillaria bombycina y M. perezdelarosae). Se estimó su distribución potencial mediante la técnica de modelado de nicho ecológico. La mayoría de las poblaciones de F. histrix se encontraron en la mitad oeste del estado de Aguascalientes, entre 1750 y 2473 m s.n.m., en cañadas de difícil acceso o en laderas con poca inclinación. Las de M. bombycina fueron encontradas en la parte suroeste del de la entidad, entre 1847 y 2417 m de altitud, en colonias en paredes de cañadas o a ras del suelo cerca de las cañadas. Por último, las de M. perezdelarosae se ubicaron en...
Se presentan medidas preventivas contra la mordedura de estos serpientess, cuestiones básicas de ... more Se presentan medidas preventivas contra la mordedura de estos serpientess, cuestiones básicas de primeros auxilios, y elementos de características en los diversos tipos de especies en el estado de Aguascalientes.
The Baja California Peninsula has over 250 islands and islets with many endemic species. Among th... more The Baja California Peninsula has over 250 islands and islets with many endemic species. Among them, rattlesnakes are the most numerous but also one of the least studied groups. The study of island rattlesnake venom could guide us to a better understanding of evolutionary processes and the description of novel toxins. Crotalus helleri caliginis venom samples were analyzed to determine possible ontogenetic variation with SDS-PAGE in one and two dimensions and with RP-HPLC. Western Blot, ELISA, and amino-terminal sequencing were used to determine the main components of the venom. The biological and biochemical activities demonstrate the similarity of C. helleri caliginis venom to the continental species C. helleri helleri, with both having low proteolytic and phospholipase A2 (PLA2) activity but differing due to the absence of neurotoxin (crotoxin-like) in the insular species. The main components of the snake venom were metalloproteases, serine proteases, and crotamine, which was the most abundant toxin group (30–35% of full venom). The crotamine was isolated using size-exclusion chromatography where its functional effects were tested on mouse phrenic nerve–hemidiaphragm preparations in which a significant reduction in muscle twitch contractions were observed. The two Mexican antivenoms could neutralize the lethality of C. helleri caliginis venom but not the crotamine effects.
Revisión del conflicto entre los humanos y las serpientes en México: origen, mitigación y perspectivas, 2021
Review of the human-snake conflict in Mexico: origin, mitigation and perspectives. The conflict b... more Review of the human-snake conflict in Mexico: origin, mitigation and perspectives. The conflict between humans and snakes has existed since unmemorable times. Fear of and aversion towards these animals may have an evolutionary explanation and may be justified because venomous and deadly snakes cause thousands of deaths around the world each year. Furthermore, social perception, the media, myths, and even religion, increase and feed this fear, resulting in the intentional slaughter of snakes being a common practice in many places. As Mexico is a mega-diverse country with more species of snakes than any other country, it faces a particularly difficult situation with regard to snake bites. Here we revise this human-snake conflict from different perspectives in order to better understand it, to propose possible solutions to reduce it, and to contribute towards snake conservation.
ZooKeys: A peer-reviewed open-access journal, 2020
Mexico is home to a large number of reptile species and has one of the greatest diversities of ve... more Mexico is home to a large number of reptile species and has one of the greatest diversities of venomous snakes, among which the rattlesnakes pertaining to the Crotalus genus stand out. Out of more than 40 species in the country, nine are found in Zacatecas: C. aquilus, C. atrox, C. basiliscus, C. lepidus, C. mo-lossus, C. polystictus, C. pricei, C. scutulatus and C. willardi. Although these reptiles are important, due to their relevance in terms of ecology, cultural use and public health, their conservation is impacted by multiple factors, such as habitat fragmentation and indiscriminate killing. Thus, most species within this genus are found in some type of risk category at both the national and international level. The purpose of this study was to determine the potential distribution and diversity of rattlesnakes at the municipal level in the understudied state of Zacatecas. To do this, we analyzed and described the global distribution of nine rattlesnake species by building species distribution models, which determined their potential distri
Resumen la familia Asteraceae es el grupo con más especies de angiospermas a nivel mundial (entre... more Resumen la familia Asteraceae es el grupo con más especies de angiospermas a nivel mundial (entre 24,000-33,000). A pesar de su diversidad, no se cuenta con suficiente información sobre la riqueza y distribución del grupo para su conservación en el centro de México. el uso de métodos no paramétricos para medir la diversidad de Asteraceae permitirá obtener información para promover su conservación en algunas áreas del centro de México. especies de la familia Asteraceae localizadas en el centro de México. cuatro áreas prioritarias para la conservación sobre todo del estado de Aguascalientes: Sierra Fría, Sierra del Laurel, Tepezalá-Asientos y Juan El Grande (2016-2019). se utilizaron los métodos no paramétricos ICE y Chao2 para estimar la riqueza; se obtuvo una curva de acumulación de especies. Asimismo, se elaboró un mapa de riqueza de especies en una cuadrícula de 5 × 5 km para identificar cuadrantes con riqueza alta. Se calculó la β-diversidad para medir diferencias en composición, anidamiento y recambio de especies entre áreas. los estimadores ICE y Chao2 indican una sobreestimación de la riqueza observada. El grado de completitud del inventario florístico de la familia en las áreas es de 62 % para ICE y de 64 % para Chao2. La β-diversidad indica alto recambio y pérdida de especies entre áreas. la riqueza y β-diversidad obtenidas son resultado del patrón espacial agrupado de las especies, presencia de especies exclusivas por área y preferencias y propiedades ecológicas específicas del grupo. Aguascalientes, β-diversidad, Chao2, Curva de acumulación de especies, Estimador de cobertura basado en incidencia. Abstract The Asteraceae is the family with the highest number of angiosperm species (24,000-33,000). Despite this diversity, information on richness and distribution of the group for conservation purposes in central Mexico is scarce. The use of non-parametric methods to measure Asteraceae species diversity will allow to obtain information to promote the conservation of some areas in central Mexico. Species of the Asteraceae in four priority conservation areas in central Mexico. Four priority conservation areas mainly located in the state of Aguascalientes: Sierra Fría, Sierra del Laurel, Tepezalá-Asientos, and Juan El Grande (2016 to 2019). Non-parametric methods ICE and Chao2 to estimate species richness were employed and a species accumulation curve was obtained. A species richness map was made in a 5 × 5 km grid to identify quadrants with high species richness. β-diversity was calculated to measure differences in composition, nesting, and species turnover among areas. ICE and Chao2 estimators indicate an overestimation of the observed species richness. The degree of completeness of the floristic inventory for Asteraceae in the study areas is 62 % for ICE and 64 % for Chao2. β-diversity indicates high turnover and species lost among areas. Richness and β-diversity obtained are the result of the species grouping spatial pattern, presence of exclusive species by area, and the ecological properties and preferences of the group. Aguascalientes, β-diversity, Chao2, Incidence-based coverage estimator, Species accumulation curve. Antecedentes: Hipótesis: Especies de estudio: Sitio y años de estudio: Métodos: Resultados: Conclusiones: Palabras clave: Background:
Invasive alien species are one of most severe threats to biodiversity and natural resources. Thes... more Invasive alien species are one of most severe threats to biodiversity and natural resources. These biological invasions have been studied from the niche conservatism and niche shifts perspective. Niche differentiation may result from changes in fundamental niche or realized niche or both; in biological invasions, niche differences between native and non-native ranges can appear through niche expansion, niche unfilling and niche stability. The Ameri-can bullfrog Lithobates catesbeianus is an invasive species that can have negative impacts on native amphibian populations. This research examines the climate niche shifts of this frog, its potential range of expansion in Mexico and the risk of invasion by bullfrog in the habitats of 82 frog species endemic to Mexico, that based on their climatic niche similarity were divided in four ecological groups. The results indicate that species in two ecological groups were the most vulnerable to invasion by bullfrog. However, the climate niche shifts of L. catesbeianus may allow it to adapt to new environmental conditions, so species from the two remaining groups cannot be dismissed as not vulnerable. This information is valuable for decision making in prioritizing areas for conservation of Mexican endemic frogs.
Invasive alien species are one of most severe threats to biodiversity and natural resources. Thes... more Invasive alien species are one of most severe threats to biodiversity and natural resources. These biological invasions have been studied from the niche conservatism and niche shifts perspective. Niche differentiation may result from changes in fundamental niche or realized niche or both; in biological invasions, niche differences between native and non-native ranges can appear through niche expansion, niche unfilling and niche stability. The Ameri-can bullfrog Lithobates catesbeianus is an invasive species that can have negative impacts on native amphibian populations. This research examines the climate niche shifts of this frog, its potential range of expansion in Mexico and the risk of invasion by bullfrog in the habitats of 82 frog species endemic to Mexico, that based on their climatic niche similarity were divided in four ecological groups. The results indicate that species in two ecological groups were the most vulnerable to invasion by bullfrog. However, the climate niche shifts of L. catesbeianus may allow it to adapt to new environmental conditions, so species from the two remaining groups cannot be dismissed as not vulnerable. This information is valuable for decision making in prioritizing areas for conservation of Mexican endemic frogs.
Invasive alien species are one of most severe threats to biodiversity and natural resources. Thes... more Invasive alien species are one of most severe threats to biodiversity and natural resources. These biological invasions have been studied from the niche conservatism and niche shifts perspective. Niche differentiation may result from changes in fundamental niche or realized niche or both; in biological invasions, niche differences between native and non-native ranges can appear through niche expansion, niche unfilling and niche stability. The Ameri-can bullfrog Lithobates catesbeianus is an invasive species that can have negative impacts on native amphibian populations. This research examines the climate niche shifts of this frog, its potential range of expansion in Mexico and the risk of invasion by bullfrog in the habitats of 82 frog species endemic to Mexico, that based on their climatic niche similarity were divided in four ecological groups. The results indicate that species in two ecological groups were the most vulnerable to invasion by bullfrog. However, the climate niche shifts of L. catesbeianus may allow it to adapt to new environmental conditions, so species from the two remaining groups cannot be dismissed as not vulnerable. This information is valuable for decision making in prioritizing areas for conservation of Mexican endemic frogs.
Vipers are among the most misunderstood and persecuted animals. They occupy most terrestrial ecos... more Vipers are among the most misunderstood and persecuted animals. They occupy most terrestrial ecosystems around the world, often at high population densities. However, certain aspects of their biology (e.g., low fecundity and slow growth) have resulted in vipers being disproportionately threatened by extinction. Despite increased extinction risk, relatively little is known about viper biology, severely limiting the development and implementation of conservation initiatives. Here, we review the conservation status of vipers globally, map species richness, and develop three indices (one reactive; one proactive; one combined index emphasising irreplaceable species facing severe threats) to identify species for which conservation action should be prioritised. Moreover, we map species richness weighted by each index to identify regions for conservation prioritisation. We ranked prioritisation scores for all species for which data were available. In doing so we identify species for which valuable data are missing and that should be prioritised for research. We additionally show that 17 species, currently listed as Not Assessed or Data Deficient by the IUCN, score sufficiently high on our Threat Index to be considered as Threatened in the future. We identify multiple regions for which viper conservation action should be prioritised. These areas broadly correlate with species richness patterns, suggesting that species richness may be an effective proxy for conservation planning. Finally, we discuss the major gaps in knowledge, as well as the major threats facing vipers.
Vipers are among the most misunderstood and persecuted animals. They occupy most terrestrial ecos... more Vipers are among the most misunderstood and persecuted animals. They occupy most terrestrial ecosystems around the world, often at high population densities. However, certain aspects of their biology (e.g., low fecundity and slow growth) have resulted in vipers being disproportionately threatened by extinction. Despite increased extinction risk, relatively little is known about viper biology, severely limiting the development and implementation of conservation initiatives. Here, we review the conservation status of vipers globally, map species richness, and develop three indices (one reactive; one proactive; one combined index emphasising irreplaceable species facing severe threats) to identify species for which conservation action should be prioritised. Moreover, we map species richness weighted by each index to identify regions for conservation prioritisation. We ranked prioritisation scores for all species for which data were available. In doing so we identify species for which valuable data are missing and that should be prioritised for research. We additionally show that 17 species, currently listed as Not Assessed or Data Deficient by the IUCN, score sufficiently high on our Threat Index to be considered as Threatened in the future. We identify multiple regions for which viper conservation action should be prioritised. These areas broadly correlate with species richness patterns, suggesting that species richness may be an effective proxy for conservation planning. Finally, we discuss the major gaps in knowledge, as well as the major threats facing vipers.
Sigala Rodríguez, J. J., A. Encarnación Luévano, E. Meza Rangel, M. Harfush Meléndez y E. Sigala ... more Sigala Rodríguez, J. J., A. Encarnación Luévano, E. Meza Rangel, M. Harfush Meléndez y E. Sigala Meza (Eds). 2016.Avances en el estudio, manejo y conservación de la diversidad zoológica de México: El XXII Congreso Nacional del Zoología en Mazunte, Oaxaca. Sociedad Mexicana de Zoología y Universidad Autónoma de Aguascalientes
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