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A New Species of Pygmy-Owl (Strigidae: Glaucidium) from the Pacific Slope of the Northern Andes
Abstract
We describe a new species of pygmy-owl that is restricted to very wet cloud forest at 1,400 to 2,000 m in elevation along the Pacific slope of the western Andes of Colombia and Ecuador. This taxon had been long overlooked as a result of its morphological similarity and geographic proximity to the Andean Pygmy-Owl (Glaucidium jardinii), but it is vocally very distinct and exhibits subtle but consistent morphological differences as well. Vocally, the new species is most similar to the Costa Rican-Panamanian form G. costaricanum and to the nominate subspecies of Northern Pygmy-Owl (G. gnoma), but again, consistent differences exist in vocalizations and morphology. Glaucidium costaricanum has long been considered a subspecies of G. jardinii, but at least one recent author treated it as a subspecies of G. gnoma. Genetic, vocal, ecological, and morphological data indicate that G. costaricanum should be elevated to species level, and it along with the new species are considered allospecies within the Northern Pygmy-Owl superspecies complex.
... Historically, this species was overlooked due to its parapatric distribution and similar appearance with the Andean Pygmy-Owl (G. jardinii) until Robbins and Stiles (1999) distinguished the 2 as separate species based on differences in morphology and vocalizations. Justification for speciation was further corroborated through molecular analysis of the mitochondrial cytochrome-b gene of certain pygmy-owl taxa (Heidrich et al. 1995). ...
... Despite exhibiting both diurnal and crepuscular activity, and vocalizing on moonlit nights, they are difficult to detect (Freile and Restall 2018). Observations over the last 2 decades suggest Cloud-forest Pygmy-Owls are a regional endemic (Enríquez 2017) occupying wet cloud forests along the western Andes of Ecuador and Colombia at elevations of 1,400-2,000 m, but as high as 2,247 m (Robbins and Stiles 1999, Fierro-Calderón and Montealegre 2010, Freile and Restall 2018. ...
... In Ecuador, Cloud-forest Pygmy-Owls have been reported in areas of the western Pichincha province, including Tandayapa, Mindo, and Guajalito, and the western Charchi province in Chical (Robbins andStiles 1999, Freile et al. 2003). Additional reports have come from the northern Imbabura, central Cotopaxi, and southern El Oro province (Freile et al. 2003, Freile andCastro 2013). ...
This study reports on findings about the natural history of the Cloud-forest Pygmy-Owl (Glaucidium nubicola). Recently described as a species, the general ecology of the Cloud-forest Pygmy-Owl remains poorly documented. Three banded individuals at a private reserve in the province of Pichincha, Ecuador, are used to describe its habitat use, diet items, and individual longevity. Our observations suggest this local population prefers wet primary cloud forest and appears to have a generalist diet. Multiple recaptures of a banded individual indicate a longevity record of 5 years. Additionally, ectoparasites were found on 2 out of 3 captured individuals.
... For these reasons the Colombian Chocó remains one of the biologically least-known regions in the Neotropics (Salaman and Stiles 1996). Increasing attention in the past decade has culminated in the description of three new bird species from the wettest subtropical forests of the Chocó EBA: Chocó Vireo Vireo masteri (Salaman & Stiles 1996), Chocó Tapaculo Scytalopus chocoensis (Krabbe & Schulenberg 1997), and Cloud-forest Pygmy-Owl Glaucidium nubicola (Robbins & Stiles 1999). These discoveries highlight the potential for new discoveries. ...
A new species of Henicorhina wood-wren (Aves, Troglodytidae) is described from the Munchique massif of the Western Andes of Colombia. The Munchique Wood-Wren Henicorhina negreti is closely related to and probably derived from the Gray-breasted Wood-Wren Henicorhina leucophrys of Central and South America. Henicorhina negreti appears restricted to a narrow band of extremely wet, stunted cloud forest on the upper Pacific slope, characterized by nearly continuous fog, high epiphyte loads and frequent landslides; it is abruptly replaced in taller forest at lower elevations on this slope by H. l. brunneiceps, and on the drier east slope by H.l. leucophrys. The new species differs from adjacent forms of H. leucophrys in its distinctly barred abdomen, dark juvenal plumage, relatively short tail and longer tarsi. Its song is also very distinct, and the adjacent forms of H. leucophrys do not respond to it while they do to each others (despite the fact that the new species occurs between them). Conversely, the new species does not respond to songs of H. l. leucophrys or H. l. brunneiceps, strongly suggesting that it is reproductively isolated from them and has distinct habitat requirements. Similarities between the ecology of H. negreti and that of H. leucoptera, another restricted-range endemic sympatric but not syntopic with H. leucophrys, are discussed. Possible threats to H. negreti due to forest clearance and global climate change are discussed, and we suggest that the species be accorded Critically Endangered status.
... Andean Pygmy-Owl (Glaucidium jardinii): One was mistnetted at Camp 1 (see photo in Flórez et al. 2004). In the Western Andes it had only been collected above Cali in Valle, whereas a sight record from southern Chocó (Hilty & Brown 1986) probably represents the recently described (Robbins & Stiles 1999) Cloud Forest Pygmy-owl (Glaucidium nubicola). ...
Realizamos una exploración ornitológica en el Páramo de Frontino, el páramo más grande de los Andes Occidentales de Colombia y rara vez visitado por los ornitólogos. Presentamos aquí los primeros registros para la cordillera de Geranoaetus melanoleucus, Hapalopsittaca amazonina, Lurocalis rufiventris, Grallaria alleni, Myornis senilis, Notiochelidon flavipes, así como de Uropsalis segmentata, Acestrura mulsanti y Leptopogon rufipectus. Las últimas tres especies habían sido registradas antes en el sur de Antioquia, pero no habían sido publicadas. Obtuvimos ampliaciones significativas de distribución latitudinal para 23 especies y ampliaciones superiores a los 300 m de la distribución altitudinal para 26 especies. Se discuten aspectos biogeográficos de la cordillera, y se incluye un inventario de las especies registradas en la exploración.
... Stomach contents of one museum specimen had insect remains and one lizard (ANSP 181044 [holotype]) and another specimen had insects (ANSP 180178) [36]. ...
Ecuador territory barely surpasses 28 million hectares, but it is home to 29 owl species, which represent 62% of all owl species in South America. Knowledge of the trophic ecology of owls is fundamental for understanding how they correlate with their environment, which organisms they prey upon, and to which extent they are beneficial for humans' health. Although publications in this field have grown in Ecuador in recent years, background information is still deficient. At present, the diet of a handful of species has been studied in this Andean country, and for a few other species, there is only anecdotal information, such as stomach contents of specimens, held in scientific collections. In this chapter, we review knowledge about the diet of owl species occurring in Ecuador and provide guidelines for the study of pellets with the aim of motivating more research in this field.
We present extensions of geographical or altitudinal distributions for 25 species of birds from 11 localities in the Western Andes of Colombia, obtained between 2003 and 2012. We found several endemic species with restricted distributions, closely associated with topographic formations such as the Pinche, Munchique, Farallones de Cali, Tatamá and Frontino massifs. We describe potential threats to the avifauna, mainly caused by human activities producing transformation of land and forest cover due to the proliferation of illicit crops and illegal mining; the presence of illegal armed groups delays the continuation of research and access to unexplored areas of this region.
Here I present a new locality (Santa María, Boyacá) in the Andean-Orinoco Llanos foothills for the Band-bellied Owl (Pulsatrix melanota). These new records represent a northward extension of ca. 500 km of this nocturnal raptor, which was previously known from the Amazonian foothills in southern Colombia.
Describimos al tororoi de Urrao (Grallariidae: Grallaria urraoensis), una nueva especie de passeriforme suboscino endémica de los bosques altoandinos del Páramo de Frontino, sector norte de la Cordillera Occidental de los Andes de Colombia. La nueva especie es similar al Tororoi de Miller (Grallaria milleri) de la Cordillera Central, pero difiere de esta especie en sus vocalizaciones y por ser ligeramente más grande, sin banda pectoral, con coloración café-oliva más opaca por encima, gris claro uniforme en las partes inferiores y bridas blanquecinas. La nueva especie se encuentra en el sotobosque de bosques nublados primarios y secundarios dominado por bambúes del género Chusquea entre elevaciones de 2500 a 3200 m en la localidad tipo. Presentamos anotaciones sobre la ecología, distribución, comportamiento, reproducción, vocalizaciones y conservación de esta nueva especie. Los bosques de montaña del norte de la Cordillera Occidental donde se encuentra el tororoi de Urrao están amenazados debido a deforestación, fragmentación y exploración minera. Estos factores, junto con la distribución geográfica y ecológica restringida de la nueva especie, hacen altamente prioritarios esfuerzos para su conservación.
Los bosques montanos de los Andes colombianos han sido severamente transformados por las actividades agropecuarias, y por eso la gran mayoría de los bosques andinos se encuentran actualmente aislados. En la cordillera Occidental esto ha ocasionado descensos en las poblaciones de aves y ha provocado extinciones locales de especies vulnerables. El objetivo de este estudio fue determinar la importancia relativa que poseen dos localidades de esta cordillera, San Antonio y Chicoral, para la conservación de las aves, entre ellas algunas especies endémicas y amenazadas. Para esto, caractericé atributos de diversidad para las comunidades de aves en ambos sitios, como son riqueza, composición y abundancia. Teniendo un total de 50 puntos de conteo en cada localidad, ubicados en transectos de 1.5 km de longitud y separados entre sí mínimo 150 m, realicé conteos visuales y auditivos. Los muestreos fueron realizados entre junio y noviembre de 2008, visitando cada punto una vez al mes. En total registré 147 especies, 126 en San Antonio y 112 en Chicoral. El Índice de Jaccard (Ij = 0.74) y el análisis de ordenación indicaron que ambas localidades son muy similares en la composición y abundancia de su avifauna. Los resultados de este estudio resaltan la importancia de estos bosques en el contexto regional, ya que albergan poblaciones de aves características de los Andes colombianos, incluyendo especies de importancia particular para la conservación. Aunque actualmente en ambas zonas hay asentamientos humanos, estos fragmentos de bosque son áreas de reserva importantes dentro de un paisaje en el que es cada vez más difícil crear reservas en lugares completamente prístinos. Finalmente, teniendo en cuenta que ambas localidades fueron establecidas como AICAs, los resultados de este estudio están apoyando esta decisión.
A Permo-Triassic reconstruction of western Pangea (North America, South
America, Africa) is proposed that is characterized by (1) definition of
the North Atlantic fit by matching of marginal offsets (fracture zones)
along the opposing margins, (2) a South Atlantic fit that is tighter
than the BuIlard fit and that is achieved by treating Africa as two
plates astride the Benue Trough and related structures during the
Cretaceous, (3) complete closure of the Proto-Atlantic Ocean between
North and South America, accomplished by placing the Yucatan block
between the Ouachita Mountains and Venezuela, (4) a proposed Hercynian
suture zone that separates zones of foreland thrusting from zones of
arc-related magmatic activity; to the northwest of this suture lie the
Chortis block and Mexico and most of North America, and to the southeast
lie South America, the Yucatan Block, Florida and Africa, and (5)
satisfaction of paleomagmatic data from North America, South America,
and Africa. Beginning with the proposed reconstruction, the relative
motion history of South America with respect of North America is defined
by using the finite difference method. Within the framework provided by
the proposed relative motion history, an evolutionary model for the
development of the Gulf of Mexico and Caribbean region is outlined in a
series of 13 plate boundary reconstructions at time intervals from the
Jurassic to the present. The model includes (1) formation of the Gulf of
Mexico by 140 Ma, (2) Pacific provenance of the Caribbean plate through
the North America-South America gap during Cretaceous time, (3)
Paleocene-Early Eocene back arc spreading origin for the Yucatan Basin,
whereby Cuba is the frontal arc and the Nicaragua Rise-Jamaica-Southern
Hispaniola is the remnant arc, and (4) 1200 km of post-Eocene cumulative
offset along both the Northern and Southern Caribbean Plate Boundary
Zones, allowing large-scale eastward migration of the Caribbean plate
with respect to the North and South American Plates.
A new species of Pygmy-Owl, genus Glaucidium, is described from the Amazonian forest. It is separated from G. minutissimum, now restricted to South-eastern Brazil and Central America, by its voice and shorter tail. The type-locality is from Rondônia, but the species seems widespread, with geographical races awaiting description from northern Pará, Northeastern Brazil, and possibly Central America. A detailed survey of this overlooked canopy-living Pygmy-Owl is under way.
We used starch-gel electrophoresis to assess variability at 41 genetic loci in 208 individuals from 11 breeding populations of the Western Flycatcher (Empidonax difficilis) complex. Genic variability was substantial in most populations and equivalent to levels found in other avian taxa. A sample of E. d. insulicola from Santa Catalina Island, however, showed reduced heterozygosity and an unusually low percentage of polymorphic loci. We attribute this to a bottleneck at the time of the original colonization. Nei's genetic distances among populations of one taxon ranged from D̄ = 0.0003 (in E. d. difficilis) to D̄ = 0.0033 (in E. d. hellmayri). Intertaxon Nei's D̄ ranged from 0.009 (E. d. insulicola vs. E. d. difficilis) and 0.0149 (E. d. difficilis vs. E. d. hellmayri) to 0.0228 (E. d. insulicola vs. E. d. hellmayri). to 0.0228 (E. d. insulicola vs. E. d. hellmayri). F statistics revealed significant population subdivision within the complex. With Slatkin's rare-allele method we estimated the gene-flow parameter, Nm. Mainland populations experience moderately high gene flow (9.62 immigrants/generation). In contrast, Santa Catalina Island receives an estimated 0.093 immigrants/generation, pointing to very low gene flow and essential genetic isolation.
Genetic distances yielded phenograms and distance Wagner trees that provide hypotheses for the relationships and phylogenesis of populations in western North America. The lineage leading to modern E. d. difficilis split from that leading to E. flavescens in the mid-Pleistocene at 866,800 yr BP; the ancestors of modern E. d. difficilis diverged from those of present-day E. d. hellmayri at 248,700 yr BP; and the stock leading to modern E. d. insulicola budded from the lineage that became E. d. difficilis in the late Pleistocene, approximately 187,000 yr BP.
Empidonax d. difficilis and E. d. hellmayri nest sympatrically and mate assortatively in the Siskiyou region of northern California. Interbreeding has not been demonstrated conclusively, and we regard these taxa as biologic species. In the absence of a test of sympatry, the well-differentiated form E. d. insulicola of the California Channel Islands cannot be proved to be a biologic species. It is clearly a phylogenetic species, however, in the sense of Cracraft.
This paper documents the extent of deforestation in western Ecuador and what is known about its effect on biodiversity. Maps are provided comparing the extent of relatively undisturbed forested areas in aboriginal times, 1958, and 1988. Patterns of floristic diversity and endemism are discussed in light of the massive deforestation, and evidence of extinction of plant species from four florula sites is provided. The naturally fragmented nature of much of the western Ecuadorian forest is discussed, both in terms of evolutionary effects and implications for long-term conservation.
Convergence of the North and South American blocks and northeastward movement of the East Pacific-Caribbean plate during the Late Cretaceous and early Tertiary led to the Laramide tectonic and igneous activity that has been recorded in the geology of the circum-Caribbean region. Volcanism in Central America and the initiation of major transcurrent faulting along northern South America during the late Eocene suggest that the Caribbean decoupled from the East Pacific plate near the end of the Laramide Orogeny. Lack of post-Eocene structural activity in the Greater Antilles is consistent with the initiation of eastward movement of the Caribbean plate during the Eocene. The evolution of the Cayman Trough and the history of orogenic activity in Cuba can be explained by assuming that Caribbean lithosphere was transferred to the Americas plate as the trough developed from west to east. As each new section was added to the eastward-growing trough, a new transform fault formed in the Caribbean lithosphere to connect the eastern end of the trough with the Cuban Trench. This west to east stepping of the plate boundary transferred "Caribbean" lithosphere to the Americas plate and allowed underthrusting and related tectonic activity to continue longer in eastern than in western Cuba. The presence of intermediate depth earthquakes and high seismicity along the Puerto Rico Trench suggest that the Atlantic lithosphere which underthrust Puerto Rico prior to the Oligocene is beginning to break away from the Americas plate. Fault displacements inferred along the Caribbean-Americas boundary in the Greater Antilles are equivalent to a constant post-Eocene eastward movement of 0.5 cm/yr for the Caribbean plate.
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Systematic biologists have directed much attention to species concepts because they realize that the origin of taxonomic diversity is the fundamental problem of evolutionary biology. Questions such as, What are the units of evolution? and, How do these units originate? thus continually capture the attention of many. It is probably no exaggeration to say that most believe the “systematic” aspects of the problem have been solved to a greater or lesser extent, whereas the task before us now is to understand the “genetic” and “ecologic” components of differentiation, i. e., those aspects often perceived to constitute the “real mechanisms” of speciation: A study of speciation is, to a considerable extent, a study of the genetics and evolution of reproductive isolating mechanisms (Bush, 1975, p. 339). ... a new mechanistic taxonomy of speciation is needed before population genetics, which deals with evolutionary mechanisms, can be properly integrated with speciation theory; that is, the various modes of speciation should be characterized according to the various forces and genetic mechanisms that underly [sic] the evolution of isolating barriers (Templeton 1980, p. 720).