Climate change is expected to cause shifts in species distributions worldwide, threatening their viability due to range reductions and altering their representation in protected areas. Biodiversity ...hotspots might be particularly vulnerable to climate change because they hold large numbers of species with small ranges which could contract even further as species track their optimal habitat. In this study, we assessed the extent to which climate change could cause distribution shifts in threatened and range-restricted birds in Colombia, a megadiverse region that includes the Tropical Andes and Tumbes-Choco-Magdalena hotspots. To evaluate how climate change might influence species in this region, we developed species distribution models using MAXENT. Species are projected to lose on average between 33 and 43 % of their total range under future climate, and up to 18 species may lose their climatically suitable range completely. Species whose suitable climate is projected to disappear occur in mountainous regions, particularly isolated ranges such as the Sierra Nevada de Santa Marta. Depending on the representation target considered, between 46 and 96 % of the species evaluated may be adequately represented in protected areas. In the future, the fraction of species potentially adequately represented is projected to decline to 30–95 %. Additional protected areas may help to retain representativeness of protected areas, but monitoring of species projected to have the largest potential declines in range size will be necessary to assess the need of implementing active management strategies to counteract the effects of climate change.
Aichi Target 12 of the Convention on Biological Diversity (CBD) contains the aim to ‘prevent extinctions of known threatened species’. To measure the degree to which this was achieved, we used expert ...elicitation to estimate the number of bird and mammal species whose extinctions were prevented by conservation action in 1993–2020 (the lifetime of the CBD) and 2010–2020 (the timing of Aichi Target 12). We found that conservation action prevented 21–32 bird and 7–16 mammal extinctions since 1993, and 9–18 bird and two to seven mammal extinctions since 2010. Many remain highly threatened and may still become extinct. Considering that 10 bird and five mammal species did go extinct (or are strongly suspected to) since 1993, extinction rates would have been 2.9–4.2 times greater without conservation action. While policy commitments have fostered significant conservation achievements, future biodiversity action needs to be scaled up to avert additional extinctions.
Urbanization is a persistent and widespread driver of global environmental change, potentially shaping evolutionary processes due to genetic drift and reduced gene flow in cities induced by habitat ...fragmentation and small population sizes. We tested this prediction for the eastern grey squirrel (Sciurus carolinensis), a common and conspicuous forest‐dwelling rodent, by obtaining 44K SNPs using reduced representation sequencing (ddRAD) for 403 individuals sampled across the species' native range in eastern North America. We observed moderate levels of genetic diversity, low levels of inbreeding, and only a modest signal of isolation‐by‐distance. Clustering and migration analyses show that estimated levels of migration and genetic connectivity were higher than expected across cities and forested areas, specifically within the eastern portion of the species' range dominated by urbanization, and genetic connectivity was less than expected within the western range where the landscape is fragmented by agriculture. Landscape genetic methods revealed greater gene flow among individual squirrels in forested regions, which likely provide abundant food and shelter for squirrels. Although gene flow appears to be higher in areas with more tree cover, only slight discontinuities in gene flow suggest eastern grey squirrels have maintained connected populations across urban areas in all but the most heavily fragmented agricultural landscapes. Our results suggest urbanization shapes biological evolution in wildlife species depending strongly on the composition and habitability of the landscape matrix surrounding urban areas.
Site conservation is among the most effective means to reduce global biodiversity loss. Therefore, it is critical to identify those sites where unique biodiversity must be conserved immediately. To ...this end, the concept of key biodiversity areas (KBAs) has been developed, seeking to identify and, ultimately, ensure that networks of globally important sites are safeguarded. This methodology builds up from the identification of species conservation targets (through the IUCN Red List) and nests within larger-scale conservation approaches. Sites are selected using standardized, globally applicable, threshold-based criteria, driven by the distribution and population of species that require site-level conservation. The criteria address the two key issues for setting site conservation priorities: vulnerability and irreplaceability. We also propose quantitative thresholds for the identification of KBAs meeting each criterion, based on a review of existing approaches and ecological theory to date. However, these thresholds require extensive testing, especially in aquatic systems.
The Chestnut‐capped Piha Lipaugus weberi sp. nov., is described from sub‐Andean forest on the northern slope of the Central Cordillera of the Colombia Andes. The new species appears most closely ...related to Lipaugus fuscocinereus of the Northern Andes including the Central Cordillera, but is much smaller, with a distinctive chestnut‐brown crown, yellow orbital ring, two modified primaries in the male, an overall darker grey coloration and unique vocalizations. It appears to be restricted to a narrow belt of premontane very humid forests (1500–1820 m asl) where it is fairly common. The restricted range and specific ecological requirements of Lipaugus weberi make the species of great conservation concern as the Central Cordillera has been severely deforested and remaining forests are highly fragmented. We present notes on the behaviour, ecology and conservation of this new species.
Se describe Lipaugus weberi sp. nov, de bosque subandino de la vertiente norte de la Cordillera Central de los Andes de Colombia. La nueva especie parece estar bastante relacionada con Lipaugus fuscocinereus de los Andes septentrionales incluyendo la Cordillera Central, pero es mucho más pequeña, presenta una distintiva gorra castaño opaco, anillo ocular amarillo, dos remeras primarias modificadas, la coloración gris más oscura y vocalizaciones ünicas. Esta especie se restringe a una franja angosta de bosque muy hümedo premontano (1500–1820 msnm), donde es relativamente comün. El rango restringido y los requerimientos ecológicos especificos de Lipaugus weberi hacen que esta especie sea de gran relevancia para la conservación, más aün debido al estado de deforestación severa de la Cordillera Central, en la cual los bosques remanentes son muy fragmentados. Presentamos anotaciones sobre la ecologia, el comportamiento y la conservación de esta nueva especie.
On the basis of field observations and two specimens from two localities in the Chocó biogeographic region of western Colombia, we here describe Vireo masteri, sp. nov. This species appears to be ...most closely related to Vireo carmioli of Costa Rica and west Panama but is much smaller and has a distinctive long superciliary stripe, a feature otherwise unknown in the subgenus Vireo, of which it is the southernmost known taxon. Vireo masteri appears to be restricted to a narrow belt of premontane pluvial forests from 1200 to 1600 m on the Pacific slope of the Western Andes. We present notes on the behaviour, ecology and conservation of this new species.
Con base en observaciones en el campo y dos especímenes de dos localidades en la región biogeográfica del Chocó colombiano, describimos una nueva y distintiva especie de vireo o chiví, Vireo masteri, sp. nov. Esta especie parece mas afin a Vireo carmiloi de Costa Rica y Panamá que a cualquier otra especie, pero es de menor tamaño y tiene una lista superciliar larga y llamativa, caracteristica única en la subgénero Vireo, del cual es la forma más sureña. Vireo masteri aparentemente se restringe a una faja altitudinal angosta (1200–1600 msnm) de bosque pluvial premontano en la vertiente del Pacífico de la Cordillera Occental de los Andes colombianos. Presentamos anotaciones sobre la ecología, el comportamiento, y la conservación de esta neueva especie.
Paucity of Hematozoa in Colombian Birds Valkiūnas, Gediminas; Salaman, Paul; Iezhova, Tatjana A.
Journal of wildlife diseases,
04/2003, Letnik:
39, Številka:
2
Journal Article
Recenzirano
Odprti dostop
Sixty-four birds of 43 species were caught at six localities in Colombia during the dry season in March 1998 and investigated for hematozoa by microscopic examination of stained blood films. ...Haemoproteus coatneyi, Plasmodium vaughani, Leucocytozoon sp., and microfilariae were identified. The overall prevalence of infection was 8%. Prevalences of infection for Haemoproteus spp., Plasmodium spp., Leucocytozoon spp., and microfilariae were 3%, 2%, 2%, and 3%, respectively. All hemosporidian infections encountered were of low intensity (<1% of infected erythrocytes). The low prevalences and intensities of hemosporidian parasites in this study are in accord with other records from the Neotropics.
Based on analyses of variation in plumage, morphometrics, vocalizations, and mitochondrial and nuclear DNA sequences, we document the occurrence of interspecific hybridization between a ...Chestnut-naped Antpitta Grallaria nuchalis and a Chestnut-crowned Antpitta G. ruficapilla in a high-elevation forest fragment in the Cordillera Central of the Andes of Colombia. One hybrid individual was collected and at least two were recorded singing. The hybrid specimen exhibits a combination of phenotypic traits that exclude other species of antpittas as potential parents, and its vocalizations combine elements of songs of both of its parental species. Genetic analyses demonstrate that the hybrid has G. nuchalis mitochondrial DNA and mixed nuclear DNA with copies corresponding to G. nuchalis and G. ruficapilla alleles, demonstrating that the female parent was G. nuchalis. Hybridization is considered extremely rare in most groups of suboscine passerines, but it may be facilitated when populations are decimated as a consequence of deforestation and habitat fragmentation.
Based on analyses of variation in plumage, morphometrics, vocalizations, and mitochondrial and nuclear DNA sequences, we document the occurrence of interspecific hybridization between a ...Chestnut‐naped Antpitta Grallaria nuchalis and a Chestnut‐crowned Antpitta G. ruficapilla in a high‐elevation forest fragment in the Cordillera Central of the Andes of Colombia. One hybrid individual was collected and at least two were recorded singing. The hybrid specimen exhibits a combination of phenotypic traits that exclude other species of antpittas as potential parents, and its vocalizations combine elements of songs of both of its parental species. Genetic analyses demonstrate that the hybrid has G. nuchalis mitochondrial DNA and mixed nuclear DNA with copies corresponding to G. nuchalis and G. ruficapilla alleles, demonstrating that the female parent was G. nuchalis. Hybridization is considered extremely rare in most groups of suboscine passerines, but it may be facilitated when populations are decimated as a consequence of deforestation and habitat fragmentation.
We present significant new information on the distribution and status of 138 speciesof birds from the Andean East Slope of Colombia, based upon fieldwork between1990 and 2000 at 28 sites from central ...Dpto. Boyacá south to the Ecuador border.The first Colombian specimens of two species (Campylopterus villaviscensio, NapoSabrewing; Myrmotherula spodionota, Foothill Antwren) are reported. Three othertaxa (Ocreatus underwoodii addae, Piculus leucolaemus leucolaemus andMyiophobus p. phoenicomitra), the first two sometimes considered species distinctfrom known Colombian forms, represent first reports from Colombia based uponsightings or photographs; we add several more sightings of two species (Pipreolachlorolepidota, Iridisornis analis) previously known from single sight records. Inall, we report 35 species from the Andean East Slope of Colombia for the first time,southward range extensions on this slope for 47 species, northward extensions for21, upward or downward altitudinal extensions for 19, filling in of major discontinuitiesin distribution for 22; for ten of the latter, known from very few reports, new informationindicates a continuous distribution and far greater abundance than previouslysupposed. Range extensions and previously undiscovered populations of severalrestricted-range, Vulnerable, Near-threatened and Threatened species help toemphasize the importance of implementing conservation measures in the face of the increasing colonization pressures and insecurity. Based on our observations, wepresent several recommendations for setting conservation priorities in this rich butstill relatively poorly known region.