GABB : A global dataset of alpine breeding birds and their ecological traits

Alpine ecosystems represent varied climates and vegetation structures globally, with the potential to support rich and functionally diverse avian communities. High mountain habitats and species are under significant threat from climate change and other anthropogenic factors. Yet, no global database of alpine birds exists, with most mountain systems lacking basic information on species breeding in alpine habitats, their status and trends, or potential cryptic diversity (i.e., sub-species distributions). To address these critical knowledge gaps, we combined published literature, regional monitoring schemes, and expert knowledge from often inaccessible, data-deficient mountain ranges to develop a global list of alpine breeding bird species with their associated distributions and select ecological traits. This dataset compiles alpine breeding records for 1,310 birds, representing 12.0% of extant species and covering all major mountain regions across each continent, excluding Antarctica. The Global Alpine Breeding Bird dataset (GABB) is an essential resource for research on the ecological and evolutionary factors shaping alpine communities, as well as documenting the value of these high elevation, climate-sensitive habitats for conserving biodiversity.Peer reviewe

Multinational evaluation of genetic diversity indicators for the Kunming‐Montreal Global Biodiversity Framework

Under the recently adopted Kunming‐Montreal Global Biodiversity Framework, 196 Parties committed to reporting the status of genetic diversity for all species. To facilitate reporting, three genetic diversity indicators were developed, two of which focus on processes contributing to genetic diversity conservation: maintaining genetically distinct populations and ensuring populations are large enough to maintain genetic diversity. The major advantage of these indicators is that they can be estimated with or without DNA‐based data. However, demonstrating their feasibility requires addressing the methodological challenges of using data gathered from diverse sources, across diverse taxonomic groups, and for countries of varying socio‐economic status and biodiversity levels. Here, we assess the genetic indicators for 919 taxa, representing 5271 populations across nine countries, including megadiverse countries and developing economies. Eighty‐three percent of the taxa assessed had data available to calculate at least one indicator. Our results show that although the majority of species maintain most populations, 58% of species have populations too small to maintain genetic diversity. Moreover, genetic indicator values suggest that IUCN Red List status and other initiatives fail to assess genetic status, highlighting the critical importance of genetic indicators

Riqueza y diversidad de especies leñosas del bosque tropical caducifolio El Tarimo, Cuenca del Balsas, Guerrero.

Se describe la composición florística, la riqueza y la diversidad de especies de un bosque tropical caducifolio en la provincia florística Cuenca del Balsas, México. Se seleccionaron 4 sitios de 1000 m2 cada uno, censándose los árboles, arbustos y lianas con d.a.p. = 1 cm. En total se registraron 1456 individuos, pertenecientes a 82 especies, 56 géneros y 24 familias. Independientemente del sitio y de la forma de crecimiento, Leguminosae fue la familia con mayor número de especies y de individuos. Los géneros más diversos fueron Bursera (Burseraceae) y Cordia (Boraginaceae) con 9 y 4 especies, respectivamente. La riqueza entre los sitios varió de 43 a 55 especies y su similitud fue más alta en el nivel de familia que en el de especie. Los árboles fueron la forma de crecimiento con mayor riqueza de especies. Respecto a otros bosques tropicales caducifolios de México y del mundo, los sitios que se estudiaron en este bosque ocupan una posición baja en cuanto a sus valores de riqueza y estructura

Hummingbirds in high alpine habitats of the tropical Mexican mountains: new elevational records and ecological considerations

Most hummingbird species are distributed in tropical lowlands and mountains with few species reaching the alpine environments of high mountain peaks. Field surveys were conducted in nine alpine sites across four of the highest volcanoes in central Mexico for three years to document hummingbird occurrence, habitat use, and some aspects of behavior. We also searched through historical museum collections and online databases to document early records of hummingbirds in Mexican alpine habitats. In addition, we conducted a search through historical herbarium collections of ornithophilous plant species in alpine habitats, and a literature search on glacier retreats in Mexico to establish past and present elevational limits of alpine vegetation. We recorded the presence of four hummingbird species using floral resources across the nine study sites: Cynanthus latirostris (Broad-billed Hummingbird), Hylocharis leucotis (White-eared Hummingbird), Lampornis clemenciae (Blue-throated Hummingbird), and Selasphorus platycercus (Broad-tailed Hummingbird). The latter two species were recorded frequently throughout the growing season (May-October), whereas C. latirostris was observed on one day in July, and H. leucotis on two days in April and May. Three of the four species were observed foraging from Castilleja tolucensis, an alpine Mexican endemic herb, at 4428 m above sea level, and all four species foraged from Penstemon gentianoides at the lower alpine sites 3900-4100. At the highest elevations, we observed hummingbirds hovering and perching on rocks while feeding from flowers at ground level. Both male and female of L. clemenciae and S. platycercus were present at patches of P. gentianoides; however, with S. platycercus, males accounted for more than 80% of the individuals observed and more than 95% of individuals observed at the highest elevations. Additionally, a survey of historical records from museum collections and bird sightings from e-databases revealed only three early records of hummingbirds in alpine sites, with only one observed earlier than 1987. This suggests that hummingbirds were not recorded earlier in alpine habitats because of a lack of sampling. Nevertheless, evidence from glacial retreats and plant distributions along an elevational gradient also indicate that hummingbirds have expanded their elevational range as new habitats have opened up for colonization associated with global climate change. The results reported here are the first records of the four hummingbird species in the Mexican alpine grassland and one of the highest altitudinal records for hummingbirds in North America. We discuss the importance and conservation implications of alpine ecosystems in Mexico as habitats for hummingbirds