The Shining Sunbeam (Aglaeactis cupripennis) is a widespread and relatively common high-elevation hummingbird in the tropical Andes. Despite this, there is no comprehensive record of its natural ...history. In this study we present our findings on the diet and territorial behavior of Shining Sunbeam at sites in Peru and Ecuador. Using radio telemetry to track and observe individuals, we examined territory size and vegetation characteristics, activity budgets, diet composition, and territorial aggression. We found that average territory size was 0.13 ha (SD 0.05) with 100% minimum convex polygon estimation and 0.19 ha (SD 0.06) with 95% kernel density estimation. We found high variation in territory sizes, which was not explained by locality, year of data collection, or flower density. The diet of the Shining Sunbeam within our study sites was composed primarily of nectar from flowers of the tree Oreocallis grandiflora (Proteaceae), which comprised 93% (SD 9) of all nectar feeding events in Peru and 99% (SD 1) in Ecuador. Other flowering plant resources included Brachyotum, Centropogon, Fuchsia, Gaultheria, and Macleania. Insects made up 7% (SD 4) and 3% (SD 1) of observed foraging events of A. cupripennis in Ecuador and Peru, respectively. Mean activity budgets across individual birds were 68% (SD 16) perching, 28% (SD 15) foraging, 3% (SD 3) in aggressive behavior, and 2% (SD 1) in nonaggressive flight. Of the observed aggressive interactions, the majority were directed toward other hummingbirds (77% in Ecuador and 84% in Peru). When only considering interactions with hummingbirds, most aggression was intraspecific in Ecuador (71%) but interspecific in Peru (95%). We observed aggressive behavior directed toward other common, non-hummingbird nectarivores, such as Diglossa flowerpiercers, while aggression directed toward non-nectarivores was rare. Our results highlight the need for comparative studies to better understand hummingbird foraging and territorial behavior in the Andes, and the utility of radio telemetry for studying larger hummingbird species like the Shining Sunbeam.
The diversity of permanent ectoparasites is likely underestimated due to the difficulty of collecting samples. Lice (Insecta: Phthiraptera) are permanent ectoparasites of birds and mammals; there are ...approximately 5,000 species described and many more undescribed, particularly in the Neotropics. We document the louse genera collected from birds sampled in Peru (2006-2007) and Colombia (2009-2016), from 22 localities across a variety of ecosystems, ranging from lowland tropical forest and Llanos to high elevation cloud forest. We identified 35 louse genera from a total of 210 bird species belonging to 37 avian families and 13 orders. These genera belong to two suborders and three families of lice: Amblycera, families Menoponidae (present on 131 bird species) and Ricinidae (39 bird species); and Ischnocera, family Philopteridae (119 bird species). We compared our bird-louse associations with data in Price et al. (2003) and recently published Neotropical studies. The majority of bird-louse associations (51.9%) were new, with most of these coming from Passeriformes, the most diverse avian order, with the most poorly known louse fauna. Finally, we found geographical variation in louse infestation and prevalence rates. With this study, we report the first comprehensive documentation of bird-louse associations for Colombia and substantially increase the known associations documented for Peru.
Significant changes in the climates of Central America are expected over the next century. Lowland rainforests harbor high alpha diversity on local scales (<1
km
2), yet montane landscapes often ...support higher beta diversity on 10-100
km
2 scales. Climate change will likely disrupt the altitudinal zonation of montane communities that produces such landscape diversity. Projections of biotic response to climate change have often used broad-scale modelling of geographical ranges, but understanding likely impacts on population viability is also necessary for anticipating local and global extinctions. We model species’ abundances and estimate range shifts for birds in the Tilarán Mountains of Costa Rica, asking whether projected changes in temperature and rainfall could be sufficient to imperil high-elevation endemics and whether these variables will likely impact communities similarly. We find that nearly half of 77 forest bird species can be expected to decline in the next century. Almost half of species projected to decline are endemic to Central America, and seven of eight species projected to become locally extinct are endemic to the highlands of Costa Rica and Panamá. Logistic-regression modelling of distributions and similarity in projections produced by temperature and rainfall models suggest that changes in both variables will be important. Although these projections are probably conservative because they do not explicitly incorporate biological or climate variable interactions, they provide a starting point for incorporating more realistic biological complexity into community-change models. Prudent conservation planning for tropical mountains should focus on regions with room for altitudinal reorganization of communities comprised of ecological specialists.
Species’ rarity is expressed and measured at a variety of spatial scales, and rarity at different scales could be correlated. Considerable empirical evidence has supported a positive correlation ...between spatial distribution and local numerical abundance of species, which could create a syndrome of rarity for species limited in geographic distribution and occurring at low densities even in their primary habitats. We used auditory-count data and range information for birds in the Tilarán mountains of Costa Rica to examine the abundance–distribution relationship in cloud forest species and to determine if endemic species (limited to Costa Rican–Panamanian highlands or Central America) are locally rare or restricted in ecological distribution. We found a positive correlation between abundance and distribution at the smallest spatial scale: species occupying few sites in the study area had low abundances where they occur. At larger scales, geographical distribution measured categorically was correlated with local ecological amplitude (zones occupied). Local abundance, however, was not correlated across all species with estimates of range size (km
2), although most endemics exhibited below-median abundance. Within families with endemics and cosmopolitan species, 72% of narrow endemics were among the rarest species. For most narrow endemics, we rejected the possibility that they are sufficiently specialized within their habitats to reach relatively high densities. A conclusive test of the abundance–distribution relationship at large spatial scales and evaluation of global population size for endemics will require a comprehensive analysis using abundance data from throughout species’ ranges. Such analyses for tropical species will be a long time coming, but it is meanwhile prudent to recognize that many endemics are threatened at several spatial scales, including the risks of small local populations.
This study establishes an altiudinal gradient, spanning from the highland Andes (2400 m) to lowland Amazon, as a productive region for the study of bird pollination in Southeastern Peru. The 'Manú ...Gradient' has a rich history of ornithological research, the published data and resources from which lay the groundwork for analyses of plant-bird interactions. In this preliminary expedition we documented 44 plants exhibting aspects of the bird pollination syndrome, and made field observations of hummingbird visits at three sites spanning the Manú Gradient: 2800 m (Wayqecha), 1400 m (San Pedro), and 400 m (Pantiacolla). Some of the documented plant taxa are underrepresented in the bird pollination literature and could be promising avenues for future analyses of their pollination biology. The Manú Gradient is currently the focus of a concerted, international effort to describe and study the birds in the region; we propose that this region of Southeastern Peru is a productive and perhaps underestimated system to gain insight into the ecology and evolution of bird pollination.
Observations were made on 11, 19, and 14 putatively bird pollinated plant species found at the high-, mid- and low-elevation sites along the gradient, respectively. Hummingbirds visited 18 of these plant species, with some plant species being visited by multiple hummingbird species or the same hummingbird species on differing occasions. Morphometric data is presented for putatively bird-pollinated plants, along with bill measurements from hummingbirds captured at each of three sites. Voucher specimens from this study are deposited in the herbaria of the Universidad Nacional de Agraria de La Molina (MOL), Peru and the University of British Columbia (UBC), Canada. The specimens collected represent a 'snapshot' of the diversity of bird-pollinated flora as observed over 10 day sampling windows (per site) during the breeding season for hummingbirds of Manú .
We developed aging criteria for 7 species of manakins (Pipridae) from the Mann Biosphere Reserve, Peru, based on patterns of plumage maturation and wing-feather replacement following their ...prefonnative molt, and summarize information on their morphological characteristics. Each species underwent a partial prefonnative molt, which could be identified using the presence of molt limits in the greater coverts. Some male Band-tailed Manakin (Pipra fasciicauda), Round-tailed Manakin (Ceratopipra chloromeros). Cerulean-capped Manakin (Lepidothrix coendeocapilla), and Yungas Manakin (Chiroxiphia boliviana) showed evidence of delayed plumage maturation, allowing for age classification up to the third annual cycle, whereas Blue-crowned Manakin (L. coronata caeieslipileata). Fiery-capped Manakin {Machaeropterus pyrocephalus), and Green Manakin (Cryptopipo holochlora viridor) appeared to attain definitive plumage after their second molt cycle. Morphometries showed strong overlap and were less useful for separation of age and sex classes. Our findings add to the growing list of studies that suggest many tropical passerines can be aged using primarily molt limits. Data on molt and plumage maturation are still needed for the vast majority of tropical birds in order to infonn conservation-based research and studies of avian life history. Received 8 November 2020. Accepted I October 2021.
Incubating birds can incur high energetic costs and, when faced with a trade-off between incubation and foraging, parents may neglect their eggs in favor of their own somatic needs. Extended ...incubation recesses are an example of neglect, but they are often treated as outliers and largely overlooked in studies of incubation behavior. We studied incubation rhythms of Horned Larks (Eremophila alpestris) on Hudson Bay Mountain, British Columbia, Canada, during four breeding seasons. Incubation recesses averaged 10.92 ± 0.38 min (N = 4076 2-h periods), but we observed 70 extended recesses, ranging from 59 to 387 min in duration, at 35 nests. Although rare (<1% of all daytime recesses), extended recesses occurred in all 4 yr, were longer and more frequent in colder years (60% occurred in the two coldest years), and often occurred during inclement weather (39% occurred during three storm events). Extended recesses did not appear to compensate for long attendance periods because extended recess duration was not correlated with the duration of previous on-bouts (P = 0.10, N = 70) or the mean on-bout duration of the previous 2-h period (P = 0.36, N = 70). Rather, extended recesses seemed to reflect a shift in parental investment away from their eggs and toward self-maintenance when faced with energetically stressful conditions. Extended recesses may have reduced embryo viability; egg-hatching rates were 91 ± 2.4% for nests where females did not take extended recesses and 81 ± 4.2% for nests where females did take extended recesses (P = 0.02, N = 56 nests). Extended recesses during incubation are rare events, but they may represent an important mechanism that allows birds to breed successfully in energetically challenging conditions. Durante la incubación las aves pueden incurrir en altos costos energéticos, enfrentándose a una solución costobeneficio entre incubación y búsqueda de alimento, en donde los padres podrían descuidar sus huevos para favorecer sus propios requerimientos corporales. Largas ausencias durante la incubación son un ejemplo de abandono, pero usualmente son tratadas como excepciones y pasadas por alto en estudios de comportamiento de incubación. Estudiamos los ritmos de incubación de Eremophila alpestris en la montaña Hudson Bay, British Columbia, Canadá, durante cuatro temporadas reproductivas. Las ausencias durante la incubación promediaron 10.92 ± 0.38 min (N = 4076 2-h periodos), pero observamos 70 ausencias prolongadas, que van desde 59 hasta 387 min en duración, en 35 nidos. Aunque raras (<1% ausencias durante todos los días), las ausencias prolongadas ocurrieron durante los cuatro años, pero fueron mas prolongadas y mas frecuentes en años mas fríos (60% ocurrieron en los dos años mas fríos), y usualmente ocurrieron durante eventos inclementes del climas (39% ocurrieron durante tres tormentas). Las ausencias prolongadas parecen no ser compensadas por largos periodos de incubación, debido a que estas ausencias no estuvieron correlacionada con la duración del evento anterior durante incubación (P = 0.10, N = 70) o la duración promedio del evento de incubación del periodo durante las dos horas previas (P = 0.36, N = 70). Mas bien, las ausencias prolongadas parecen reflejar un cambio en la inversión parental lejos de sus huevos y enfocada hacia su propio sustento cuando encuentran condiciones energéticamente estresantes. Las ausencias prolongadas pueden haber reducido la viabilidad del embrión; la tasas de eclosión fue de 91 ± 2.4% en nidos en donde las hembras no realizaron ausencias prolongadas y 81 ± 4.2% para nidos en donde las hembras realizaron ausencias prolongadas (P = 0.02, N = 56 nidos). Las ausencias prolongadas durante la incubación son eventos raros, pero pueden representar un mecanismos importante que permite a las aves reproducirse exitosamente en condiciones energéticamente desafiantes.
Relatively little is known about the longevity of free-living landbirds, especially in the tropics. We used mark-recapture data for birds originally banded in 2005 and 2006, and later recaptured ...between 2011 and 2016, to estimate minimum longevity for 20 species from southeastern Peru. The oldest recorded longevity was 10 years, 6 months for a Black-billed Treehunter (Thripadectes melanorhynchus). Another notable record was for a Russet-crowned Warbler (Myiothlypis coronata; 9 years, 2 months). Our estimated minimum longevity records generally reflect the findings of other researchers, indicating that tropical birds are often markedly site faithful and long-lived. Received 7 July 2017. Accepted 10 April 2018. Key words: bird banding, life history, lifespan, Manu National Park, mark-recapture, tropical birds. Se conoce relativamente poco sobre la longevidad de las aves terrestres silvestres, especialmente en los tropicos. Utilizamos datos de marca y recaptura para aves anilladas originalmente en 2005 y 2006, y luego recapturadas entre 2011 y 2016 para estimar la longevidad minima en 20 especies del sureste Peruano. La mayor longevidad registrada fue de 10 anos y 6 meses para Thripadectes melanorhynchus. Otro registro notable fuera 9 anos y 2 meses para Myiothlypis coronata. Nuestros registros de longevidad minimos estimados concuerdan con los hallazgos de otros investigadores, indicando que las aves tropicales permanecen frecuentemente en la misma localidad y son de vida larga. Palabras clave: anularmente de aves, aves tropicales, esperanza de vida, historia de vida, marca y recaptura, Parque Nacional de Manu.
ABSTRACT Incubating birds can incur high energetic costs and, when faced with a trade-off between incubation and foraging, parents may neglect their eggs in favor of their own somatic needs. Extended ...incubation recesses are an example of neglect, but they are often treated as outliers and largely overlooked in studies of incubation behavior. We studied incubation rhythms of Horned Larks (Eremophila alpestris) on Hudson Bay Mountain, British Columbia, Canada, during four breeding seasons. Incubation recesses averaged 10.92 ± 0.38 min (N= 4076 2-h periods), but we observed 70 extended recesses, ranging from 59 to 387 min in duration, at 35 nests. Although rare (<1% of all daytime recesses), extended recesses occurred in all 4 yr, were longer and more frequent in colder years (60% occurred in the two coldest years), and often occurred during inclement weather (39% occurred during three storm events). Extended recesses did not appear to compensate for long attendance periods because extended recess duration was not correlated with the duration of previous on-bouts (P= 0.10, N= 70) or the mean on-bout duration of the previous 2-h period (P= 0.36, N= 70). Rather, extended recesses seemed to reflect a shift in parental investment away from their eggs and toward self-maintenance when faced with energetically stressful conditions. Extended recesses may have reduced embryo viability; egg-hatching rates were 91 ± 2.4% for nests where females did not take extended recesses and 81 ± 4.2% for nests where females did take extended recesses (P= 0.02, N= 56 nests). Extended recesses during incubation are rare events, but they may represent an important mechanism that allows birds to breed successfully in energetically challenging conditions. RESUMEN Durante la incubación las aves pueden incurrir en altos costos energéticos, enfrentándose a una solución costo-beneficio entre incubación y búsqueda de alimento, en donde los padres podrían descuidar sus huevos para favorecer sus propios requerimientos corporales. Largas ausencias durante la incubación son un ejemplo de abandono, pero usualmente son tratadas como excepciones y pasadas por alto en estudios de comportamiento de incubación. Estudiamos los ritmos de incubación de Eremophila alpestris en la montaña Hudson Bay, British Columbia, Canadá, durante cuatro temporadas reproductivas. Las ausencias durante la incubación promediaron 10.92 ± 0.38 min (N= 4076 2-h periodos), pero observamos 70 ausencias prolongadas, que van desde 59 hasta 387 min en duración, en 35 nidos. Aunque raras (<1% ausencias durante todos los días), las ausencias prolongadas ocurrieron durante los cuatro años, pero fueron mas prolongadas y mas frecuentes en años mas fríos (60% ocurrieron en los dos años mas fríos), y usualmente ocurrieron durante eventos inclementes del climas (39% ocurrieron durante tres tormentas). Las ausencias prolongadas parecen no ser compensadas por largos periodos de incubación, debido a que estas ausencias no estuvieron correlacionada con la duración del evento anterior durante incubación (P= 0.10, N= 70) o la duración promedio del evento de incubación del periodo durante las dos horas previas (P= 0.36, N= 70). Mas bien, las ausencias prolongadas parecen reflejar un cambio en la inversión parental lejos de sus huevos y enfocada hacia su propio sustento cuando encuentran condiciones energéticamente estresantes. Las ausencias prolongadas pueden haber reducido la viabilidad del embrión; la tasas de eclosión fue de 91 ± 2.4% en nidos en donde las hembras no realizaron ausencias prolongadas y 81 ± 4.2% para nidos en donde las hembras realizaron ausencias prolongadas (P= 0.02, N= 56 nidos). Las ausencias prolongadas durante la incubación son eventos raros, pero pueden representar un mecanismos importante que permite a las aves reproducirse exitosamente en condiciones energéticamente desafiantes. PUBLICATION ABSTRACT
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