A New Species of Pygmy-Owl (Strigidae: Glaucidium) from the Pacific Slope of the Northern Andes

This is the published version. Copyright Central Ornithology Publication OfficeWe 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. Received 20 July 1998, accepted 2 December 1998

The Status and Distribution of Birds in Missouri

The Status and Distribution of Birds in Missouri by Mark B. Robbins is a comprehensive, up-to-date compilation of the 435 species of birds that have been documented in Missouri. Primarily as a result of climate change, many species’ status and distribution have changed in the past twenty-five years. Those changes are highlighted in this treatise. The dramatic change in avian nomenclature and taxonomy will be apparent when comparing this work with past publications and field guides. There are four maps and 24 photographs of unusual birds recorded in the state, all in color. This is the first edition; the second edition is located at https://hdl.handle.net/1808/30959

Social Organization of the Band-Tailed Manakin (Pipra fasciicauda)

This is the published version. Copyright Central Ornithology Publication OfficeI studied the social organization of the Band-tailed Manakin (Pipru fasciicaudu) for 6.5 months in 1980 in undisturbed, lowland rain forest of southeastern Peru. Dominant males maintained closely-packed territories at localized sites in seasonally flooded forest. Within each territory, an alpha male, usually a beta male, and occasionally one or more non-territorial adult males performed complex, coordinated displays for attracting and exciting females. Alpha males were extremely sedentary, spending almost the entire day on territory. Beta males were less sedentary and visited with other alpha males at the lek. Alpha males encouraged all visiting conspecifics, except contiguous territorial owners, to join them in display. Territorial males showed no interspecific territoriality, except toward other lekking piprids. Once a female was attracted to a territory, only the alpha male actively courted her, while the subordinate male(s) observed from the adjacent vegetation. All disruptions of an alpha male courting a female were by subordinates associated with the territory. Beta males occupied the dominant position in both instances where there was a change in territorial ownership. Two types of acquisition of the alpha position were involved: (1) an alpha male was displaced by the beta male; and, (2) a beta male inherited ownership when the alpha male disappeared

Origins of Late-Breeding Nomadic Sedge Wrens in North America: Limitations and Potential of Hydrogen-Isotope Analyses of Soft Tissue

This is the published version. Copyright Central Ornithology Publication OfficeThe nomadic Sedge Wren (Cistothorus platensis) breeds primarily in mesic grasslands in north-central North America. Following breeding in these regions from late May to early July, however, the species then “appears” en masse in the tallgrass prairie region farther south (e.g., Missouri and Kansas) and to the east to breed again from mid-July to early August (Herkert et al. 2001). The provenance of birds appearing in late summer to breed in these areas remains unknown because of problems inherent in mark—recapture surveys. Recent studies have shown how endogenous markers may be used to infer origins of individual birds. We analyzed levels of the stable hydrogen isotope 2H (δD) from liver, muscle, and claws of Sedge Wrens from known northern breeding locations first to establish the relationships between δD in the wrens' tissue and mean δD in precipitation during the growing season (δDp ). From these relationships we derived expected values (mean and 95% CI) for three sites in Kansas and Missouri where late breeders colonized. The observed values of δD in these late breeders were primarily within the range expected for those locations, but more individuals than expected had δD values higher than expected. In addition, in birds apparently originating from north or south of Kansas and Missouri, the values of δD in claws were positively correlated with those in other tissues, in contrast to those with the “local” signal. This supports the idea that the isotopic outliers at these sites were more recent arrivals. For small-bodied birds like the Sedge Wren, however, the isotopic approach based on soft tissues is limited to a very narrow temporal window of inference because of rapid elemental turnover. This greatly restricts the use of this technique in inferring origins of small nomadic species

Taxonomy and Natural History of Nyctiphrynus rosenbergi (Caprimulgidae)

This is the published version. Copyright Central Ornithology Publication Offic

First Description of the Nest and Eggs of the Moss-Backed Tanager (Buthraupis [Bangsia] Edwardsi)

This is the published version. Copyright Central Ornithology Publication Offic

Extensive Protein Similarity of the Hybridizing Chickadees Parus atricapillus and P. carolinensis

This is the published version. Copyright Central Ornithology Publication OfficeStarch gel electrophoresis of proteins was used to assess genetic differentiation and introgression across a contact zone between Parus atricapillus and P. carolinensis. Little or no differentiation was found at 35 presumed genetic loci, even between distantly allopatric population samples. Nei's (1978) genetic distance (D) was <O.001 for all comparisons. In contrast, Parus gambeli, another chickadee known to hybridize with atricapillus, was well differentiated at 3 loci (D - 0.065). While the data suggest that atricapillus and carolinensis are closely related, they do not allow conclusions on the extent of introgression across the contact zone. The implications of these data are discussed in the light of the emerging pattern of isozyme variation in birds. Received 26 August 1985, accepted 28 March 1986

Strain Hardening in Polymer Glasses: Limitations of Network Models

Simulations are used to examine the microscopic origins of strain hardening in polymer glasses. While traditional entropic network models can be fit to the total stress, their underlying assumptions are inconsistent with simulation results. There is a substantial energetic contribution to the stress that rises rapidly as segments between entanglements are pulled taut. The thermal component of stress is less sensitive to entanglements, mostly irreversible, and directly related to the rate of local plastic arrangements. Entangled and unentangled chains show the same strain hardening when plotted against the microscopic chain orientation rather than the macroscopic strain.Comment: 4 pages, 3 figure

Morphological and Vocal Variation across a Contact Zone between the Chickadees Parus atricapillus and P. carolinensis

This is the published version. Copyright Central Ornithology Publication OfficeA contact zone between Black-capped and Carolina chickadees (Parus atricapillus and P. carolinensis) exists in southwestern Missouri. It was less than 15 km wide and paralleled the interface between the relatively treeless Great Plains and the forested Ozark Plateau. Many birds in this zone were intermediate in morphology or vocalizations or both. Moreover, both morphological and vocal discriminant analysis scores of contact zone birds were unimodally distributed and there was no correlation between morphological discriminant scores of mated males and females in the contact zone, indicating little or no assortative mating. Playback experiments demonstrated that birds to the north or south of the contact zone responded aggressively only to their own song type, while contact zone birds responded to either song type. We believe that southwestern Missouri contact zone populations are derived from extensive hybridization between atricapillus and carolinensis. Received 26 August 1985, accepted 28 March 1986