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Ítem First nesting account and breeding biology of "gould's Inca" (Coeligena torquata omissa) in Manu National Park, Peru(Wilson Ornithological Society, 2016-09-03) Londoño, Gustavo AdolfoWe present the first detailed nesting biology information for the highland Andean hummingbird Gould's Inca (Coeligena torquata omissa) at 2,200-3,000 m in Manu National Park, SE Peru. We found nine mossy cup-shaped nests lined with red fern scales containing nestlings or 1-2 synchronously hatching eggs. We obtained 17 days of internal nest temperatures from one nest, which exhibited wide circadian variation (range = 14.9-36.2 °C). We show that C. t. omissa meets the challenges of life and incubation at high altitudes by undertaking numerous (20.3 ± 0.4 trips/morning, range = 14-27) and short morning off-bouts (5.2 ± 0.2 min, range = 1-24 min). In the morning, the focal bird warmed the nest 1.7 times faster than in the afternoon where incubation bouts are long (17.8 ± 0.6 min, range = 4-56) and less frequent (10.2 ± 0.3 trips/afternoon). Incubation off-bout frequency and durations were not influenced by external temperature, suggesting strong nest insulation. On-bout durations increased with external temperature most strongly in the cold mornings. Short off-bouts and long on-bouts yielded high attentiveness (70.2%). One nestling fledged after 23 days. The eggs measured 15.2 ± 0.4 mm by 9.3 ± 0.3 mm and weighed 0.75 ± 0.03 g (n = 12). The small mossy cup nest was 81.9 ± 5.9 mm by 75.8 ± 4.4 mm wide and 73.1 ± 6.7 mm high. The inner cup was 45.7 ± 3.0 mm long by 45.6 ± 4.1 mm wide and 30.9 ± 2.5 mm deep (n = 8). Compared to C. t. torquata, we found a smaller egg width, higher nest placement and different nest substrate, but confirmed similarities in many aspects of nesting strategies.Ítem Basal metabolism in tropical birds: latitude, altitude, and the ‘pace of life’(Wiley, 2015-03-01) Londoño, Gustavo AdolfoLife history varies across latitudes, with the ‘pace of life’ being ‘slower’ in tropical regions. Because life history is coupled to energy metabolism via allocation tradeoffs and links between performance capacity and energy use, low metabolic intensity is expected in tropical animals. Low metabolism has been reported for lowland tropical birds, but it is unclear if this is due to ‘slow’ life history or to a warm, stable environment. We measured basal metabolic rates (BMR) of 253 bird species across a 2·6 km altitude gradient in Peru. We predicted higher BMR at high altitude due to lower temperatures leading to elevated thermoregulatory costs. We also tested for BMR differences between widely separated tropical regions (Peru and Panama), and between tropical- and temperate-breeding birds.Ítem Description of the nest, eggs, and nestling of Rufous-bellied Bush-Tyrants ( Myiotheretes fuscorufus )(The Wilson Ornithological Society, 2015-01-01) Londoño, Gustavo AdolfoThe Myiotheretes bush-tyrants are a small clade of Neotropical flycatchers (family: Tyrannidae) localized to narrow elevational strips in the Andes Mountains. Here, we describe the first reported nest of Rufous-bellied Bush-Tyrants (Myiotheretes fuscorufus). It was a large cup nest lined with Usnea lichen and elevated on a sheltered rock ledge behind a flowering Puya bromeliad at 2,985 m asl in the buffer zone of Manu National Park, Peru. We provide a near-complete history of the nest from eggs through fledging, and compare data with previous nesting reports for other Myiotheretes species.Ítem Morphological and behavioral evidence of Batesian mimicry in nestlings of a lowland Amazonian bird.(University of Chicago Press, 2015-06-01) Londoño, Gustavo AdolfoBecause predation is the main cause of avian nest failure, selection should favor strategies that reduce the probability of nest predation. We describe apparent Batesian mimicry in the morphology and behavior of a Laniocera hypopyrra nestling. On hatching, the nestling had a distinctive bright orange color and modified feathers all over its body, and 6 days after hatching, it started to move its head very slowly from side to side (in a "caterpillar" movement) when disturbed. These traits gave it a resemblance to a hairy, aposematic caterpillar. This species has a long nestling period for its size (20 days), perhaps due to slow provisioning rates (about one feeding per hour). We argue that the slow growth rate, combined with high nest predation, favors the evolution of antipredation mechanisms such as the unique morphological and behavioral characteristics of L. hypopyrra nestlings.