Bird conservation and biodiversity research in Mexico: status and priorities

This is the peer reviewed version of the following article: Peterson, A. T. and Navarro-Sigüenza, A. G. (2016), Bird conservation and biodiversity research in Mexico: status and priorities. J. Field Ornithol.. doi:10.1111/jofo.12146, which has been published in final form at doi:10.1111/jofo.12146. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.Mexico holds a megadiverse avifauna that includes many endemic elements, as well as rich sets of species from both farther north and farther south in the Americas. This avifauna, nonetheless, has suffered considerable losses as a consequence of long-term, intensive human activity across the landscape. We review what is known about the Mexican avifauna, specifically its diversity and endemism, and how that knowledge has and has not turned into effective conservation measures to assure the long-term integrity of the avifauna

Assumption- versus data-based approaches to summarizing species’ ranges

This is the peer reviewed version of the following article: Assumption- versus data-based approaches to summarizing species’ ranges, which will be published in final form in Conservation Biology at http://dx.doi.org/10.1111/cobi.12801. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving: http://olabout.wiley.com/WileyCDA/Section/id-828039.html#termsSpecies’ geographic distributions are mapped using various approaches for use in conservation decision-making. Some such mapping efforts have relied on modifications of coarse-resolution extent-of-occurrence maps to downscale them to fine resolutions for conservation planning. This contribution examines (1) the quality of the extent-of-occurrence maps as range summaries, and (2) the utility of refining those maps into fine-resolution distributional hypotheses. In both cases, we found significant problems: the extent-of-occurrence maps are overly simple, omit many known and well-documented populations, and likely frequently include many areas not holding populations. Refinement steps involve typological assumptions about habitat preferences and elevational ranges of species, which can introduce significant error in anticipating species’ true distributional areas; however, as no model evaluation steps are taken to assess predictive ability of models, “bad” models are not noticed. Whereas range summaries derived by these methods may be useful in coarse-grained, global-extent studies, their continued use in on-the-ground conservation challenges at fine resolutions is not advisable. On the other hand, data-driven techniques that integrate primary biodiversity occurrence data with remotely sensed data summarizing environmental dimensions, termed ecological niche modeling or species distribution modeling, with rigorous and quantitative testing of model predictions prior to any use. These data-driven approaches constitute a well-founded, widely accepted alternative with a minimum of assumptions

A Mexican case study on a centralised database from world natural history museums

The present contribution is a case study of the possibilities of using data from world scientific collections to understand the distribution and conservation of Mexican birds. Information was gathered on specimens from Mexico housed in 40 scientific collections in Mexico, the United States, Canada, and Europe. This information was compiled in a centralized database and various analyses were developed to address historical patterns of ornithological investigations in Mexico: current and potential distribution areas of the species; patterns of species richness, endemism and seasonality; and conservation applications

Genetic Variation and Differentiation in Mexican Populations of Common Bush-Tanagers and Chestnut-Capped Brush-Finches

Genetic differentiation among four Mexican populations each of Common Bush-tanagers (Chlorospingus ophthalmicus) and Chestnut-capped Brush-finches (Atlapetes brunneinucha) was evaluated using allozyme electrophoresis. In both species, although levels of within-population variation are moderate, among-population variation is extreme, including fixed differences among populations. Genetic variation is significantly reduced in some populations on the smallest habitat islands. Differentiation is apparently unrelated to geographic distance among populations, and effects of habitat island size and isolation on genetic differentiation are not clear. Populations of the Sierra de los Tuxtlas in Veracruz, however, are strongly differentiated in both species

Constructing check-lists and avifauna-wide reviews: Mexican bird taxonomy revisited

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Molecular systematics and evolution of the Cyanocorax jays

Phylogenetic relationships were studied in the genus Cyanocorax (Aves: Corvidae) and related genera, Psilorhinus and Calocitta, a diverse group of New World jays distributed from the southern United States south to Argentina. Although the ecology and behavior of some species in the group have been studied extensively, lack of a molecular phylogeny has precluded rigorous interpretations in an evolutionary framework. Given the diverse combinations of plumage coloration, size, and morphology, the taxonomy of the group has been inconsistent and understanding of biogeographic patterns problematic. Moreover, plumage similarity between two geographically disjuct species, the Tufted Jay (Cyanocorax dickeyi) from western Mexico and the White-tailed Jay (C. mystacalis) from western Ecuador and Peru, has puzzled ornithologists for decades. Here, a phylogeny of all species in the three genera is presented, based on study of two mitochondrial and three nuclear genes. Phylogenetic trees revealed the non-monophyly of Cyanocorax, and the division of the whole assemblage in two groups: “Clade A” containing Psilorhinus morio, both species in Calocitta, Cyanocorax violaceus, C. caeruleus, C. cristatellus, and C. cyanomelas, and “Clade B” consisting of the remaining species in Cyanocorax. Relationships among species in Clade A were ambiguous and, in general, not well resolved. Within Clade B, analyses revealed the monophyly of the “Cissilopha” jays and showed no evidence for a sister relationship between C. mystacalis and C. dickeyi. The phylogenetic complexity of lineages in the group suggests several complications for the understanding biogeographic patterns, as well as for proposing a taxonomy that is consistent with morphological variation. Although multiple taxonomic arrangements are possible, recommendations are for recognizing only one genus, Cyanocorax, with Psilorhinus and Calocitta as synonyms. Se estudiaron las relaciones filogenéticas en los géneros Cyanocorax, Psilorhinus y Calocitta (Aves: Corvidae), un grupo diverso de urracas del Nuevo Mundo cuyas especies se distribuyen desde el sur de los Estados Unidos hasta Argentina. Aunque la ecología y el comportamiento de algunas especies en el grupo han sido estudiadas extensamente, la falta de una filogenia molecular ha impedido la interpretación rigurosa de estos estudios en un marco evolutivo. Dadas las diversas combinaciones de coloración de plumaje, tamaño y morfología presentes en las especies del grupo, su taxonomía ha sido inconsistente y la interpretación de sus patrones biogeográficos ha sido problemática. Mas aún, la similitud de plumaje en especies que están geográficamente distantes, como Cyanocorax dickeyi del oeste de Mexico y C. mystacalis del oeste de Ecuador y Perú, ha sido difícil de interpretar. Se presenta una filogenia para todas las especies en los tres géneros, basada en el estudio de dos genes nucleares y dos genes mitocondriales. Los árboles filogenéticos mostraron la parafilia de Cyanocorax y la división de todas las especies en dos grupos: “Clado A” en el cual se encuentran Psilorhinus morio, ambas especies Calocitta, Cyanocorax violaceus, C. caeruleus, C. cristatellus, y C. cyanomelas, y “Clado B” en el cual se encuentran el resto de las especies de Cyanocorax. Las relaciones entre especies del Clado A fueron ambiguas y, en general, poco resueltas. En el Clado B, los análisis mostraron la monofilia de las especies en “Cissilopha”, pero no indicaron la monofilia de C. mystacalis + C. dickeyi. La complejidad filogenética de los linajes en el grupo sugiere varias complicaciones en el entendimiento de su biogeografía y taxonomía. Con base en los resultados filogenéticos se reconoce un solo género, Cyanocorax, con Psilorhinus y Calocitta como sinónimos

Hidden endemism, deep polyphyly, and repeated dispersal across the Isthmus of Tehuantepec: Diversification of the White-collared Seedeater complex (Thraupidae: Sporophila torqueola)

© 2018 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd. Phenotypic and genetic variation are present in all species, but lineages differ in how variation is partitioned among populations. Examining phenotypic clustering and genetic structure within a phylogeographic framework can clarify which biological processes have contributed to extant biodiversity in a given lineage. Here, we investigate genetic and phenotypic variation among populations and subspecies within a Neotropical songbird complex, the White-collared Seedeater (Sporophila torqueola) of Central America and Mexico. We combine measurements of morphology and plumage patterning with thousands of nuclear loci derived from ultraconserved elements (UCEs) and mitochondrial DNA to evaluate population differentiation. We find deep levels of molecular divergence between two S. torqueola lineages that are phenotypically diagnosable: One corresponds to S. t. torqueola along the Pacific coast of Mexico, and the other includes S. t. morelleti and S. t. sharpei from the Gulf Coast of Mexico and Central America. Surprisingly, these two lineages are strongly differentiated in both nuclear and mitochondrial markers, and each is more closely related to other Sporophila species than to one another. We infer low levels of gene flow between these two groups based on demographic models, suggesting multiple independent evolutionary lineages within S. torqueola have been obscured by coarse-scale similarity in plumage patterning. These findings improve our understanding of the biogeographic history of this lineage, which includes multiple dispersal events out of South America and across the Isthmus of Tehuantepec into Mesoamerica. Finally, the phenotypic and genetic distinctiveness of the range-restricted S. t. torqueola highlights the Pacific Coast of Mexico as an important region of endemism and conservation priority

Bird faunas of the humid montane forests of Mesoamerica: biogeographic patterns and priorities for conservation

The distribution of 335 species of birds in 33 islands of humid montane forest in Mesoamerica is summarized, and patterns of distribution, diversity and endemism are analysed. The montane forests of Costa Rica and western Panama far exceed other habitat islands considered for species-richness, richness of species endemic to Mesoamerica, and richness of species ecologically restricted to humid montane forests. Other regions, such as the Sierra Madre del Sur of Guerrero and Oaxaca, the Los Tuxtlas region of southern Veracruz and the mountains of Chiapas and Guatemala, also hold rich and endemic avifaunas. Based on patterns of similarity of avifaunas, the region can be divided into seven regions holding distinctive avifaunas (Costa Rica and western Panama; northern Central America and northern Chiapas; southern Chiapas; eastern Mexico north of the Isthmus of Tehuantepec; Sierra Madre del Sur; interior Oaxaca; and Transvolcanic Belt and Sierra Madre Occidental), which serve as useful guides for the setting of priorities for conservation action. Se resumen las distribuciones de 335 especies de aves en 33 islas de bosque humedo de montana en Mesoamerica, y se analizan patrones de distribution, diversidad y endemismo. Los bosques montanos de Costa Rica y del oeste de Panama tienen la mas alta riqueza de especies, riqueza de especies endemicas a Mesoamerica, y riqueza de especies ecologicamente restringidas a bosque humedo de montana. Otras regiones, tales como la Sierra Madre del Sur de Guerrero y Oaxaca, la region de Los Tuxtlas y las montanas de Chiapas y Guatemala, tambien tienen avifaunas ricas en especies y en endemicas. Basado en patrones de similitud de avifaunas, se puede dividir Mesoamerica en siete regiones que tienen avifaunas distintas (Costa Rica y el oeste de Panama; el norte de Centroamerica y el norte de Chiapas; el sur de Chiapas; el este de Mexico; la Sierra Madre del Sur; el interior de Oaxaca; y el Eje Neovolcanico y la Sierra Madre Occidental), las cuales pueden servir como guias en el establecimiento de prioridades para la conservation

West Nile virus in the New World: potential impacts on bird species

The past five years have seen the arrival and extremely rapid expansion of West Nile virus (WNV) in the Western Hemisphere. The rapid sweep across North America has permitted little time for developing knowledge of the virus’s potential impacts on wildlife in the New World. Given this information gap, we here summarize for the ornithological community what is known or can be anticipated for WNV’s effect on bird communities in coming years. Our particular focus is on impacts of WNV on the conservation status of birds, the principal vertebrate reservoir for the virus