Rupelramphastoides knopfi, a new genus and species of the Pici (barbets, woodpeckers, and allies), is described from Frauenweiler, a Lower Oligocene (30–34 mya) fossil site in Germany. The disarticulated skeleton of the new species constitutes the first associated remains of a fossil member of the Pici and is the smallest known species and earliest substantial fossil record of this taxon. Despite an overall resemblance to modern Ramphastidae, R. knopfi appears to be distinguished from crown group Pici by several plesiomorphic characteristics. It is classified “family incertae sedis,” pending discovery of additional, better-preserved specimens. The fossil record and geographic occurrence of the basal lineages within the crown group are in concordance with an Old World origin of the Pici. The reasons that led to extinction of tiny Pici in Europe remain uncertain, but food competition with passeriform birds during periods of limited food availability may have played a major role.

Ein winziger bartvogelähnlicher Vogel aus dem Unter-Oligozän Deutschlands: die kleinste Art und der älteste substantielle Fossilnachweis der Pici (Spechte und Verwandte)

An expedition of representatives from the Myanmar Nature and Wildlife Conservation Division and the Smithsonian National Zoological Park's Conservation and Research Center visited the town of Naung Mung on the Nam Tisang River in the extreme northern portion of Kachin State, Myanmar, during February 2004. The town is located in the sub-Himalayan region of the country at 27°29′N, 97°48′E, elevation 540 m, 118 km south of the Tibetan border and 53 km west of the border with Yunnan Province, China. The purpose of the trip was to inventory the poorly known avifauna of the premontane temperate rainforest habitat at that site. On 6 February 2004, we captured two scimitar-babblers that appeared to be representatives of the genus Jabouilleia. An additional individual of the taxon was captured in the same vicinity on 8 February 2004. These were the first records for Jabouilleia from Myanmar, and subsequent investigation showed that these specimens were members of a previously undescribed species, which we designate Jabouilleia naungmungensis, the Naung Mung Scimitar-Babbler.

Une Nouvelle Espèce de Jabouilleia (Timaliidae) dans la Région sub-Himalayenne de la Birmanie

Intraspecific patterns of autumn migration timing are not well known, particularly in the western United States. Here, we (1) describe autumn migration timing and age ratios of landbird migrants in southwestern Idaho, (2) examine differences in timing among age and sex classes, and (3) demonstrate how prebasic molt strategies affect migration timing differences between age classes. As a group, Neotropical migrants were most common from late July through early September, whereas temperate migrants were most common from mid-September into early October. Proportion of hatch-year birds was 74.5% for all migrants combined and ranged from 33.3% to 100% for individual species. Timing differences between sex classes were detected in only a few species and no general patterns emerged. In 22 of 31 Neotropical and temperate migrants examined, there were significant differences in timing between adults and hatch-year birds. In species in which adults begin fall migration before replacing flight feathers, adults migrated earlier than hatch-year birds. Conversely, in species in which adults molt flight feathers on or near the breeding grounds before departing on fall migration, hatch-year birds migrated earlier than adults in all but one case. Therefore, it appears that molt strategy is a powerful determinant of intraspecific migration timing differences and, to our knowledge, this is the first study to document this pattern among migrant passerines of North America.

Estrategias de Muda y Diferencias en el Momento de Migración Otoñal en Migrantes Terrestres en el Suroeste de Idaho

We studied the relationship between the occurrence of extrapair fertilizations (EPFs) and mating status and nesting cycle of mates, respectively, in a population of Black-browed Reed Warblers (Acrocephalus bistrigiceps). Overall, 6.4% (9 of 140) of the chicks were sired by extrapair males, and 13.5% (5 of 37) of the broods contained at least one extrapair chick. Socially polygynous males were cuckolded more frequently than socially monogamous males (40.0% and 3.7%, respectively). In three of four cases where cuckolded males were polygynous, the fertile periods of their mates overlapped. Except for two floating males that obtained EPFs, five out of seven cuckolder males were paired. Males succeeded in EPFs when the fertile period of the extrapair females largely overlapped the incubation period of their own mates. These findings are consistent with the hypothesis that there are trade-offs between extrapair copulation activity and both mate guarding and rearing of nestlings.

Fertilisation Extraconjugale chez Acrocephalus bistrigiceps: Effets des Mâles Infidèles et Cocus sur le Statut de Couple et le Cycle de Nidification

High-value resources are often defended aggressively by consumers, which can alter assemblage structure and dynamics. Here, we describe a system of nectarivorous bird assemblages exploiting pockets of eucalypt woodlands that differ dramatically in flowering and provision of nectar. The behavioral dominant, the Red Wattlebird (Anthochaera curunculata), aggressively reduces the occurrence and activities of other honeyeaters of the genera Lichenostomus and Melithreptus on sites of intense flowering. The latter genera predominate in moderately flowering areas, but few honeyeaters occupy poorly flowering sites. To understand such systems, in which temporal variation in habitat quality can be great, one needs to consider not only the disparity in habitat quality among locations but also the spatial extent of habitats of different quality. Isoleg analysis is a theoretical tool developed to understand how dominant and subordinate species partition habitats as a function of their respective densities. Our results suggest that isoleg analysis needs to be developed with spatial explicitness to capture variation in extent of habitats of different qualities and consequent effects on the usefulness of aggression for domination of resources.

La Disponibilidad de Recursos Controla la Composición de los Ensambles de Aves a través de las Agresiones Interespecíficas

Food allocation among nestlings has a strong influence on parental fitness. Maximizing fledging success in a favorable environment requires food distribution based on offspring need signals. However, food limitation, differences among individual nestlings in their quality, or variation in the costs of rearing different young may result in preferential allocation of food by parents. If signals of nestling quality or need change in meaning with age, parents are expected to adjust their feeding rules to those changes. We examined food allocation in broods of Collared Flycatchers (Ficedula albicollis), a sexually size-monomorphic passerine. In a multivariate analysis, we investigated the role of sex, size, condition, position, and begging intensity in two nestling ages. Size, condition, and sex of nestlings did not affect parental decisions. Begging intensity and nestling position, however, had a role in food allocation in both age categories. Both parents preferred the more intensely begging nestlings. Males did not show clear position preference in the “young” age category, but had preferred positions with older nestlings. Female position preference was observed in both age categories. Preferred positions of male and female parents differed; still, we observed overall position preference.

Asignación de Alimentos en Nidadas de Ficedula albicollis: ¿Cambian las Reglas con la Edad de los Pichones?

Unusual among birds, the bill tips in crossbills (Loxia spp.) overlap in the vertical plane, with the tip of the lower mandible to either the left or right of the tip of the upper mandible when viewed from above. Patterns observed in wild populations and experimental foraging data suggest that a 1:1 ratio of left- to right-crossing individuals is maintained by frequency-dependent natural selection in some populations, and that genetic drift causes deviation from a 1:1 ratio in other populations. Both processes require a genetic basis for this remarkable polymorphism, yet few data are available that address whether, and how, mandible crossing direction is heritable. To test for a genetic basis of this trait (single or quantitative, autosomal or sex-linked), we analyzed resemblance in mandible crossing direction between related captive-bred individuals of several crossbill taxa with standard statistical techniques as well as modern animal model methodology. Surprisingly, we did not find statistically significant support for a genetic basis of mandible crossing direction. Comparisons of the ratio of left- to right-crossing males and females in wild populations also did not support a sex-linked quantitative genetic basis. We conclude that mandible crossing direction may have uncharacteristically low heritability, but we cannot rule out that it is nongenetically determined.

La Dirección de Cruzamiento de la Mandíbula en las Especies de Loxia no Presenta Base Genética

We examined a 63-year data set of dates of first spring sightings for 96 species of migrant birds at Delta Marsh, Manitoba, and considered the influence of local climate change on those arrival dates. Mean monthly spring temperatures increased (0.6–3.8°C) for all four months considered; however, trends for February and March were stronger than those for April and May. Over the 63-year period, 27 species significantly altered their arrival dates. Most of those species arrived significantly earlier; whereas only two species, Greater Yellowlegs (Tringa melanoleuca) and Lesser Yellowlegs (T. flavipes), arrived significantly later over time. About half of the migrants showed significant relationships between arrival dates and mean temperature for their month of arrival. Fifteen species showed significantly earlier arrivals over time and a significant relationship between arrival date and temperature. We also characterized migrants by taxon, breeding status, and wintering location to determine whether there were any trends for altered arrivals within certain groups. Waterfowl, species that breed at Delta Marsh, and short-distance migrants showed slightly higher incidences of advancing arrival dates compared with other groups. Our results provide evidence that climate warming has influenced spring migration arrival dates of several species in Manitoba.

Tendances à Long-terme des Dates d'Arrivée Printanières des Oiseaux Migrateurs dans le Delta Marsh, Manitoba, en Relation avec les Changements Climatiques

Information on population connectivity throughout the annual cycle has become more crucial, because populations of many migratory birds are in decline. One such species is the American Woodcock (Scolopax minor), which inhabits early-successional forests in eastern North America. Although band recoveries have proved useful for dividing populations of this game bird species into an Eastern Region and Central Region for management purposes, these data do not provide enough detail to determine the breeding population of origin of birds recovered on stopover and wintering areas. To obtain more fine-scale data, we undertook a phylogeographic study of American Woodcock populations throughout their primary breeding range in the eastern United States and Canada using mitochondrial DNA (mtDNA) sequences from the hypervariable control region I (CRI) and ND6 gene. Despite high haplotype diversity, nucleotide diversity was low and there was no phylogeographic structure among American Woodcock populations across the species range, with birds from many states and provinces in both management regions sharing identical haplotypes. Results suggest recent or ongoing gene flow among populations, with asymmetric movement of birds between migration flyways. As has been demonstrated for several other avian species in North America, American Woodcock appear to have undergone a rapid population expansion following the late Pleistocene glacial retreat. Thus, a combination of historical demographic factors and recent or ongoing gene flow mask any population structure based on mtDNA that might accrue from philopatry to breeding areas observed in studies of marked birds.

Phylogéographie de Scolopax minor: Est-ce que les Unités de Gestion Basées sur les Données de Retour de Bagues Reflètent les Unités de Gestion Basées sur la Génétique?

In many situations, selection should favor females that bias the sex ratio of their offspring. Two commonly examined factors potentially influencing off- spring sex ratio are paternal ornamentation and maternal condition. Male junglefowl with larger combs are attractive to females. I housed female Red Junglefowl (Gallus gallus) with sterile male consorts and artificially inseminated them with sperm from other males that the females never saw. I found no relationship between either the comb size of the consort or the comb size of the sperm donor and the sex ratio of the offspring. I previously reported a significant sex ratio bias related to maternal mass in Red Junglefowl. However, that analysis was based on sex ratio data not weighted for brood size and assuming a normal distribution. Here, I show that this effect disappears when I conduct a more appropriate analysis weighting sex ratio according to brood size and accounting for the binomial error distribution. I also failed to find evidence that male chicks hatch from larger eggs than female chicks. These results suggest that Red Junglefowl females may not bias the sex ratio of their brood in response to either their own condition or the attractiveness of the males with whom they copulate. Furthermore, these results demonstrate the importance of choosing the correct methods of sex ratio analysis.

Falta de Evidencia de Asignación Adaptativa Diferencial entre Sexos en Gallus gallus

In species with long-term partnerships, optimal mate preferences may differ from actual mate choice, and pair displays that advertise individual quality may be expected. We examined the relationship between nest-building and nestling-provisioning effort in Neotropical Buff-breasted Wrens (Thryothorus leucotis) to determine whether male or female expenditure during nest construction was used as an indicator of subsequent parental ability. Buff-breasted Wrens build two nest types: breeding nests used for raising offspring, and “dormitory“ nests built year-round and used by pairs for roosting overnight. The building effort of males was greater than that of their mates for dormitory nests, whereas male and female effort were similar during breeding-nest construction and nestling provisioning. Despite large within-sex variation in building and provisioning efforts, male and female effort within pairs were significantly positively correlated for construction of both nest types and for nestling feeding. Effort expended by males during dormitory-nest construction was positively correlated with nestling-provisioning effort, whereas female building effort was not. No relationship existed between effort in breeding-nest construction and nestling provisioning in either sex. These results suggest that effort in dormitory-nest construction was an indicator of male Buff- breasted Wren parental ability. Females that survived to the year following observation built dormitory nests at a lower rate than those that disappeared, which suggests that nest building may be costly and that by building more than females, males may increase the survival prospects of their partners. Dormitory-nest building by males may play dual roles throughout the year, indicating parental ability and investment in the partnership.

La Construcción de Nidos es un Indicador de la Calidad de los Padres en la Especie Neotropical Monógama Thryothorus leucotis

The method of collecting and analyzing boluses to characterize the cephalopod diet of albatrosses has been used in many diet studies. However, no study has validated this method. We compared boluses and stomach samples from Gray-headed Albatrosses (Thalassarche chrysostoma) and Black-browed Albatrosses (T. melanophris) to (1) study the consumption and diversity of cephalopods in these species, (2) investigate biases associated with each sampling method, and (3) estimate the number of samples needed to characterize these albatross’s cephalopod diet. We found that collection and analysis of boluses is a simple, efficient, and noninvasive method for assessing the cephalopod diet of these albatross species, but it is inadequate for characterizing the more easily digestible dietary components, such as fish and crustaceans. Both boluses and stomach samples showed that the two albatross species fed on cephalopods of similar sizes and from the same families (Ommastrephidae, Onychoteuthidae, and Cranchiidae). Furthermore, the main prey species (Martialia hyadesi, Kondakovia longimana, and Galiteuthis glacialis) and the total number of cephalopod species consumed (18–24 species) were the same for both albatrosses. To include all cephalopod species, using a sample-randomization technique, a minimum of 61 and 43 boluses were needed for Gray-headed and Black- browed albatrosses, respectively; but to adequately describe the diversity and size frequency of the main prey species, 82 and 371 boluses would be needed.

Les Pelotes de Réjection: Une Méthode Efficace pour Évaluer la Proportion de Céphalopodes dans le Régime Alimentaire chez les Albatros

I reconstructed the phylogeny of 12 Ramphastos toucan taxa using mitochondrial DNA (mtDNA) sequences. This analysis identified two major groups, including a monophyletic smooth-billed yelping clade and a clade including most, but not all, the channel-keel-billed croakers. Within the R. tucanus and R. vitellinus groups, uncorrected mtDNA divergences are relatively low and mtDNA sequences from several subspecies are paraphyletic. One exception to low divergences within the R. vitellinus group is R. v. ariel from southeastern Brazil, which on average differs from all other R. vitellinus sampled by 2.9%. Character reconstructions on the phylogeny indicate that the ancestral Ramphastos was most likely a large-bodied channel- keel-billed croaker. Furthermore, an assessment of the patterns of bill shape, voice, and both plumage and bare-part coloration characters suggests that bill shape and voice have significant phylogenetic signal but that color characters do not. Sympatric Ramphastos taxa are not closely related in the phylogeny; therefore, character reconstructions indicate that the extreme similarity in coloration patterns between many sympatric Ramphastos pairs is most likely attributable to a combination of convergence or parallelism (homoplasy) and shared ancestral character states (symplesiomorphy).

Filogenética Molecular de los Tucanes del Género Ramphastos: Implicaciones para la Evolución de la Morfología, las Vocalizaciones y la Coloración

Because of their smaller size and isolation, island populations tend to be more divergent and less genetically variable than mainland populations. We collected DNA samples from nine Galápagos Hawk (Buteo galapagoensis) island populations, covering the species’ entire range. Neutral minisatellite DNA markers were used to calculate within-island genetic diversity and between-island genetic differentiation (F_ST). Typically, these markers mutate too quickly to be informative in such studies. However, in very small, isolated populations, concerns about high mutational rate are obviated by the relative force of genetic drift. Individuals within islands had the highest levels of reported genetic uniformity of any natural bird population, with mean within-population band-sharing similarity values ranging from 0.693 to 0.956, increasing with decreasing island size. Galápagos Hawks exhibit cooperative polyandry to varying degrees across islands; however, we did not find an association between degree of polyandry and genetic variability. Between-island F_ST values ranged from 0.017 to 0.896, with an overall archipelago value of 0.538; thus, most populations were genetically distinct. Also, we documented higher levels of genetic similarity between nearby populations. Our results indicated negligible gene flow among most Galápagos Hawk populations, and genetic drift has played a strong role in determining structure at these minisatellite loci.

Genética de Poblaciones de Buteo galapagoensis: Monomorfismo Genético dentro de Poblaciones Aisladas

Food abundance, weather, and female body condition are believed to influence the timing of breeding and reproductive performance of birds. We simultaneously studied the effects of weather and food abundance on reproduction in Tree Swallows (Tachycineta bicolor) while experimentally reducing female condition and foraging efficiency by clipping some flight feathers prior to egg laying. Control females laid larger clutches earlier in the season, had longer incubation periods, and raised heavier nestlings than experimental females. Fledging success did not differ after controlling for laying date and brood size. Greater insect abundance was associated with laying earlier in the season, heavier eggs, and shorter incubation periods. Most likely, feather-clipping affected clutch size through reduced foraging efficiency, which delayed the date of laying, rather than through loss of body condition. This outcome is consistent with the idea that Tree Swallows are “income” breeders that base their timing of reproduction on short-term rates of food intake near the time of breeding. Contrary to studies of other species, Tree Swallows do not appear to time their laying so that hatching will coincide with seasonal peaks in food supply. Rather, they appear to breed when temperature and food abundance are sufficient to allow females of a given body condition to initiate egg laying.

Efectos de la Abundancia de Alimento, del Clima y de la Condición de las Hembras sobre la Reproducción en Tachycineta bicolor

Suboptimal conditions during embryonic development can affect offspring fitness. Both egg quality and incubation behavior can affect hatching success, hatching mass, and subsequent offspring performance. These effects may differ between male and female offspring. We manipulated the prebreeding body condition of Zebra Finches (Taeniopygia guttata), using diets of different protein content. To separate possible effects on egg quality of parental body condition and incubation conditions, we did a cross-fostering experiment. We analyzed embryo survival and hatching mass with respect to body condition of the egg-laying parent, body condition of the incubating foster parent, and offspring sex. Embryos were not affected by the condition of the egg-laying parent. Eggs incubated by parents in better condition suffered less embryo mortality than those incubated by parents in poorer condition, but only when overall embryo mortality was low. Hatching mass was also affected by the incubating foster parent’s body condition. And hatchlings incubated by parents in good condition were heavier than those incubated by parents in poor condition. Female hatchlings from late-laid eggs were heavier, in comparison with the size of the egg from which they hatched, than female hatchlings from earlier-laid eggs. No such effect was found for males. Therefore, male and female embryos may differ in their sensitivity to suboptimal conditions during embryonic development. These results suggest that parental body condition during incubation can affect offspring fitness.

Efectos de las Condiciones de Incubación y el Sexo de las Crías sobre el Desarrollo Embrional y la Supervivencia en Taeniopygia guttata

Many species, including shorebirds, feed during both day and night, yet little is known about how this affects behavior and habitat preferences. European Golden-Plovers (Pluvialis apricaria) and Northern Lapwings (Vanellus vanellus) feeding on arable farmland were more widely dispersed at night: nocturnal flocks were smaller, typically monospecific, and occurred in many more fields than diurnal mixed-species flocks. Diurnal numbers of European Golden-Plovers could not be used to predict nocturnal numbers; this indicates that ranging behavior differed between day and night. For both species, nocturnal feeding was recorded on almost all nights, irrespective of moon phase. Northern Lapwing nocturnal feeding activity decreased with increasing cloud cover and decreasing ground temperature, but no clear relationships were detected between European Golden-Plovers’ nocturnal feeding activity and environmental variables. Habitat selection differed between day and night, and between species at night. Diurnal studies of habitat choice and site selection may misrepresent the full requirements of such species.

Los Estudios Diurnos no Predicen la Preferencia Nocturna de Hábitat ni la Selección Nocturna de Sitio en Pluvialis apricaria y Vanellus vanellus

The Southwestern Willow Flycatcher (Empidonax traillii extimus; here- after “flycatcher”) is a federally listed endangered species that breeds in densely vegetated riparian habitats dominated by native and exotic plants, including introduced monotypic saltcedar (Tamarix ramosissima). Some workers have theorized that saltcedar is unsuitable habitat for the flycatcher, primarily because it generally supports a smaller and less diverse invertebrate community (the flycatcher's food base) than native habitats (e.g. Salix spp.). However, differences in insect communities between native and saltcedar habitats are not proof that saltcedar habitats are inferior. The only way to evaluate whether the habitats differ in dietary or energetic quality is to document actual food limitation or its manifestations. Measurements of an individual's body condition and metabolic state can serve as indicators of environmental stressors, such as food limitation and environmental extremes. We captured 130 flycatchers breeding in native and saltcedar habitats in Arizona and New Mexico and measured 12 variables of physiological condition. These variables included body mass, fat level, body condition index, hematocrit, plasma triglycerides, plasma free fatty acids and glycerol, plasma glucose and beta-hydroxybutyrate, plasma uric acid, total leukocyte count, and heterophil-to-lymphocyte ratio. We found substantial sex-based differences in the condition of male and female flycatchers. Ten of the 12 measures of physiological condition differed significantly between the sexes. In all cases where male and female condition differed (except mass), the differences suggest that males were in poorer condition than females. We found few habitat-based differences in flycatcher condition. Only 3 of the 12 physiological condition indices differed significantly between habitats. Our data show that, at least in some parts of the flycatcher's range, there is no evidence that flycatchers breeding in saltcedar habitats exhibit poorer nutritional condition or are suffering negative physiological affects.

Diferencias entre Hábitats y Sexos en la Condición Fisiológica de Individuos Reproductivos en Empidonax traillii extimus

The avifauna of Madagascar presents a complicated taxonomic and biogeographic problem. Although Madagascar was once connected to Africa, the birds of the island are not all of African origin. The Madagascar Pygmy Kingfisher (Ispidina madagascariensis) is sometimes placed in the African genus Ispidina and sometimes in the Southeast Asian genus Ceyx. We sequenced 755 base pairs of mitochondrial DNA from a fragment of the NADH dehydrogenase subunit II (ND2) and from the complete NADH dehydrogenase subunit III (ND3). We used these data to construct phylogenetic hypotheses for the Alcedinidae. Using these phylogenies, we evaluate previous hypotheses of relationships of I. madagascariensis. Although we cannot reject the hypothesis that I. madagascariensis is indeed a member of Ispidina, tree-building analyses support a relationship not with Ispidina or Ceyx, but instead with members of the African genus Corythornis. These data suggest that certain behaviors and plumage types have evolved several times in the Alcedinidae.

Relations Phylogénétiques de Ispidina madagascariensis

The following critiques express the opinions of the individual evaluators regarding the strengths, weaknesses, and value of the books they review. As such, the appraisals are subjective assessments and do not necessarily reflect the opinions of the editors or any official policy of the American Ornithologists’ Union.

The following critiques express the opinions of the individual evaluators regarding the strengths, weaknesses, and value of the books they review. As such, the appraisals are subjective assessments and do not necessarily reflect the opinions of the editors or any official policy of the American Ornithologists’ Union.

The following critiques express the opinions of the individual evaluators regarding the strengths, weaknesses, and value of the books they review. As such, the appraisals are subjective assessments and do not necessarily reflect the opinions of the editors or any official policy of the American Ornithologists’ Union.

The following critiques express the opinions of the individual evaluators regarding the strengths, weaknesses, and value of the books they review. As such, the appraisals are subjective assessments and do not necessarily reflect the opinions of the editors or any official policy of the American Ornithologists’ Union.