Rosana Aramburú

Reproductive parameters in the critically endangered Blue-throated Macaw: limits to the recovery of a parrot under intensive management.

Rediscovered in the wild twenty years ago, the breeding biology of wild Blue-throated Macaws remains largely unexplored, yet is essential to its effective conservation and recovery. Here, we analyse reproductive parameters in an intensively managed wild population of Blue-throated Macaws, providing the first data on the breeding biology of this critically endangered species. During the six-year study period, 2007–2012, the number of active breeding pairs either remained constant or decreased, depending on the site, and no new breeding pairs were discovered despite extensive searching. We documented nesting attempts in natural cavities in dead palms or live hardwoods, and artificial nest boxes. Egg-laying was concentrated during the end of dry season and the beginning of the wet season, August through December. Hatching failure was the greatest cause of egg losses. Half of the breeding attempts of Blue-throated Macaws produced at least one fledging, on average two, after a 85 days nestling period. An average of 4.3 nestlings per year fledged from all known wild nests combined. Each pair lost roughly 65% of its initial reproductive investment at each nesting attempt. In most successful nesting attempts of individualized pairs, a new nesting attempt was not detected the following year. All monitored breeding pairs showed high nest site fidelity, reusing hardwood-tree cavities and nest boxes. Our findings will aid conservation efforts by refining current actions and prompting new approaches towards the conservation and recovery of the Blue-throated Macaw.

Occupancy and abundance of large macaws in the Beni savannahs, Bolivia

Monitoring of wild populations is central to species conservation and can pose a number of challenges. To identify trends in populations of parrots, monitoring programmes that explicitly take detectability into account are needed. We assessed an occupancy model that explicitly accounted for detectability as a tool for monitoring the large macaws of Bolivias Beni savannahs: the blue-throated Ara glaucogularis , blue-and-yellow Ara ararauna and red-and-green macaws Ara chloropterus . We also evaluated the joint presence of the three macaw species and estimated their abundance in occupied areas. We modelled occupancy and detection for the three macaw species by combining several site and visit covariates and we described their conditional occupancy. Macaws occupied two thirds of the surveyed area and at least two species occurred together in one third of this area. Probability of detection was 0.48–0.86. For each macaw species, occupancy was affected by the abundance of the other two species, the richness of cavity-nesting species, and the distance to the nearest village. We identified key priority areas for the conservation of these macaws. The flexibility of occupancy methods provides an efficient tool for monitoring macaw occupancy at the landscape level, facilitating prediction of the range of macaw species at a large number of sites, with relatively little effort. This technique could be used in other regions in which the monitoring of threatened parrot populations requires innovative approaches.

Nest Survival and Predation in Blue-Fronted Parrots Amazona aestiva: Effects of Nesting Behaviour and Cavity Characteristics

In this study we analyse factors affecting nest survival in Blue-fronted Parrots Amazona aestiva breeding in the Chaco region of northern Argentina. We combined temporal and environmental variables in order to determine which best explain variation in overall nest survival and in predation dependent nest survival. We predicted that high and deep cavities, that are inaccessible to snakes and other predators, would have high daily survival rates. We compared the relative effects on nest survival of time of the breeding season, stage of the nesting cycle, and characteristics of the nest cavity. We modelled daily survival rate (DSR) for all observed nests, and daily survival rate for nests that had been predated (daily survival rate in relation to predation exclusively, DSRp). Nest predation accounted for 50% of nest failures. DSR was on average 0.989, translating into an apparent hatching success of 0.39. DSR decreased with time of breeding and increased with nest age. DSRp decreased with time of breeding and inclination of the nest cavity entrance hole and increased with height from the ground of the entrance hole. There was a quadratic effect of nest age on DSRp, such that daily survival was highest during incubation, lowest at hatching and the early nestling stage, but increasing throughout the remainder of the nestling stage. This effect became more pronounced as the breeding season advanced. Year and observer effects did not affect the probability of survival. Temporal patterns and characteristics of the nest cavity explained most of the variation in nest survival in Blue-fronted Parrots, which highlights the relevance of including these covariates in future studies of nest survival in parrots, and has important management and conservation implications.

Primer registro del Calancate Común Aratinga a. acuticaudata (Aves: Psittacidae) como huésped nativo primario de Ornithocoris toledoi Pinto (Hemiptera: Heteroptera: Cimicidae)

First record of Blue-Crowned Parrot Aratinga a. acuticaudata (Aves: Psittacidae) as primary native host of Ornithocoris toledoi Pinto (Cimicidae: Hemiptera: Heteroptera). The primary natural host of cimicid bug Ornithocoris toledoi Pinto (Hemiptera: Heteroptera: Cimicidae) is presented as Blue- Crowned Parrot Aratinga a. acuticaudata (Aves: Psittacidae). Its presence in the Chaco province is also a new distributional record of this bug in Argentina. A brief discussion about the taxonomy is also given and some population parameters are compared with those of other bug species. Finally, we discuss possible infestation ways in the current state of knowledge, including other birds (Furnariidae) and bats (Chiroptera).

Artrópodos presentes en nidos de cotorra Myiopsitta monachus monachus (Aves: Psittacidae)

Arthropods in Monk Parakeet nests (Aves: Psittacidae). The objective of this work is to communicate a list of artropodofauna which is in Monk Parakeet (Myiopsitta monachus monachus) nests at several localities in Buenos Aires province. One nest and 43 beds of fresh green material that the Monk Parakeets deposited in the breeding chamber were collected. Arthropods were extracted, identified under binocular microscope, and characterized by their diets. Species were found whitin class Arachnida (Acarina, Pseudoescorpionida and Araneae), mainly predators and hematophagous. Within class Insecta, were found blood-sucking species, predators, detritivores, phytophagous, nectarivorous, and xilophagous, among others. The orders most represented were Diptera (8 families) and Coleoptera (12 families). The rest of the species belonged to the orders Collembola, Psocoptera, Hymenoptera, Phthiraptera, Hemiptera and Lepidoptera.