Genetic evidence of extra-pair paternity and intraspecific brood parasitism in the monk parakeet

Introduction: The monk parakeet (Myiopsitta monachus) is a widespread invasive species native to southern South America that has become established in many regions of the world. Monk parakeets breed in a large, fully enclosed structure built from twigs, which consist of one to many individual brooding chambers. The species has been considered to be socially and genetically monogamous. However, genetic relatedness of adults to juveniles in the native area was found to be lower than expected for monogamy. To assess the significance of this discrepancy, we examined individual and population genetic patterns of microsatellite loci at two sites in Córdoba province, Argentina. Results: We sampled 154 nestlings and 42 adults in Córdoba, Argentina. Mean value of pairwise relatedness of nestlings within chambers was about 0.40. Contrarily, relatedness of nestlings between chambers was close to zero. We found a considerable degree of variation in nestling pairwise relatedness and parentage within chambers, including chambers with combinations of unrelated, half-sib, and full-sib nestlings. The proportion of sibling relatedness indicated monogamy in 47% and extra pair-paternity in 40% of the chambers. We also found intra-brood parasitism in 3% of the chambers. Conclusions: Our results indicate that the monk parakeet is sexually polygamous in its native range in Argentina, which is consistent with the observed mean value of relatedness of adults to juveniles of about 0.4. We also confirm the existence of intra-brood parasitism. High density of monk parakeets may favor occurrence of extra-pair paternity and intra-brood parasitism in the native sites.Fil: Martinez, Juan Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales; Argentina;Fil: de Aranzamendi, Maria Carla. Consejo Nacional de Invest.cientif.y Tecnicas. Centro Cientifico Tecnol.conicet - Cordoba. Instituto de Diversidad y Ecologia Animal; Argentina;Fil: Masello, Juan Francisco. Max Planck Institute for Ornithology; Alemania; Consejo Nacional de Invest.cientif.y Tecnicas. Centro Cientifico Tecnol.conicet - Cordoba. Instituto de Diversidad y Ecologia Animal; Argentina;Fil: Bucher, Enrique Hugo. Consejo Nacional de Invest.cientif.y Tecnicas. Centro Cientifico Tecnol.conicet - Cordoba. Instituto de Diversidad y Ecologia Animal; Argentina

Are haematological parameters related to body condition, ornamentation and breeding success in wild burrowing parrots Cyanoliseus patagonus

Haematology and plasma biochemistry values are useful tools for ecological research. They have been used to investigate the physiological state and the adaptation of individuals to their habitat, changes in nutritional state of birds, body condition, the level of parasite infestation, male quality, the physical condition of nestlings, etc. In the present study we tested the role of haematological and plasma biochemistry values in burrowing parrots Cyanoliseus patagonus (Aves, Psittaciformes) for determining individual quality and condition. We measured triglyceride levels, plasma protein levels, plasma hue and erythrocyte sedimentation rate of nestlings and breeding adults in a colony in the north of Patagonia, Argentina. We found that plasma triglyceride levels strongly relate to changes in individual condition. Plasma levels of triglycerides were found to be strongly related to mass change, hatching order and brood size in nestlings. Levels of triglycerides were found to reflect reproductive effort in adults: males fledging larger broods had decreased levels of triglycerides. Adults with lower body condition had increased erythrocyte sedimentation rates. Plasma hue showed a strong relationship with an ornamental trait, the red abdominal patch of male adults, and with parameters of structural body size. Thus, we have shown that haematological and plasma biochemistry values, especially plasma levels of triglycerides, are good indicators of individual quality and condition in nestlings and breeding birds

Prevalence of blood parasites in seabirds - a review

<p>Abstract</p> <p>Introduction</p> <p>While blood parasites are common in many birds in the wild, some groups seem to be much less affected. Seabirds, in particular, have often been reported free from blood parasites, even in the presence of potential vectors.</p> <p>Results</p> <p>From a literature review of hemosporidian prevalence in seabirds, we collated a dataset of 60 species, in which at least 15 individuals had been examined. These data were included in phylogenetically controlled statistical analyses of hemosporidian prevalence in relation to ecological and life-history parameters. <it>Haemoproteus </it>parasites were common in frigatebirds and gulls, while <it>Hepatozoon </it>occurred in albatrosses and storm petrels, and <it>Plasmodium </it>mainly in penguins. The prevalence of <it>Haemoproteus </it>showed a geographical signal, being lower in species with distribution towards polar environments. Interspecific differences in <it>Plasmodium </it>prevalence were explained by variables that relate to the exposure to parasites, suggesting that prevalence is higher in burrow nesters with long fledgling periods. Measures of <it>Plasmodium</it>, but not <it>Haemoproteus </it>prevalences were influenced by the method, with PCR-based data resulting in higher prevalence estimates.</p> <p>Conclusions</p> <p>Our analyses suggest that, as in other avian taxa, phylogenetic, ecological and life-history parameters determine the prevalence of hemosporidian parasites in seabirds. We discuss how these relationships should be further explored in future studies.</p

Half a world apart? overlap in nonbreeding distributions of Atlantic and Indian ocean thin-billed prions

Distant populations of animals may share their non-breeding grounds or migrate to distinct areas, and this may have important consequences for population differentiation and dynamics. Small burrow-nesting seabirds provide a suitable case study, as they are often restricted to safe breeding sites on islands, resulting in a patchy breeding distribution. For example, Thin-billed prions Pachyptila belcheri have two major breeding colonies more than 8,000 km apart, on the Falkland Islands in the south-western Atlantic and in the Kerguelen Archipelago in the Indian Ocean. We used geolocators and stable isotopes to compare at-sea movements and trophic levels of these two populations during their non-breeding season, and applied ecological niche models to compare environmental conditions in the habitat. Over three winters, birds breeding in the Atlantic showed a high consistency in their migration routes. Most individuals migrated more than 3000 km eastwards, while very few remained over the Patagonian Shelf. In contrast, all Indian Ocean birds migrated westwards, resulting in an overlapping nonbreeding area in the eastern Atlantic sector of the Southern Ocean. Geolocators and isotopic signature of feathers indicated that prions from the Falklands moulted at slightly higher latitudes than those from Kerguelen Islands. All birds fed on low trophic level prey, most probably crustaceans. The phenology differed notably between the two populations. Falkland birds returned to the Patagonian Shelf after 2-3 months, while Kerguelen birds remained in the nonbreeding area for seven months, before returning to nesting grounds highly synchronously and at high speed. Habitat models identified sea surface temperature and chlorophyll a concentration as important environmental parameters. In summary, we show that even though the two very distant populations migrate to roughly the same area to moult, they have distinct wintering strategies: They had significantly different realized niches and timing which may contribute to spatial niche partitioning

Alerta: loros en peligro

Las poblaciones de casi todas las especies de loros del mundo están disminuyendo. Las principales amenazas: el comercio de mascotas y el avance de la agricultura. Un nuevo informe realizado por especialistas en aves llama la atención sobre la necesidad urgente de realizar acciones de conservación.Facultad de Ciencias Naturales y Muse

Moving polewards in winter: a recent change in the migratory strategy of a pelagic seabird?

Background: During the non-breeding period, many birds migrate to milder areas, found closer to the equator than their breeding sites. Opposite movements are very rare. In the Southern Ocean, the abundance of C-13 declines markedly with more southern latitude, providing a characteristic C-13 isoscape. This can be used as a tracer for the movement of seabirds between breeding and inter-breeding areas, by comparing stable isotope ratios of feathers grown at different times of the year. Results: We studied seasonal movements of Thin-billed prions (Aves, Procellariiformes), breeding at the Subantarctic Falkland/Malvinas Islands, compared with those of Wilson's storm-petrels breeding in the Antarctic South Shetland Islands. The two species showed opposite migratory movements. While Wilson's storm-petrels moved to warmer waters north of the Drake Passage in winter, Thin-billed prions showed a reversed movement towards more polar waters. Carbon stable isotope ratios in recent and historical feathers indicated that poleward winter movements of Thin-billed prions were less common historically (45% in 1913-1915), and have only recently become dominant (92% in 2003-2005), apparently in response to warming sea temperatures. Conclusions: This study shows that pelagic seabirds can rapidly change migration strategies within populations, including migration towards more poleward waters in winte

Population size, provisioning frequency, flock size and foraging range at the largest known colony of Psittaciformes: the Burrowing Parrots of the north-eastern Patagonian coastal cliffs

We here describe the largest colony of Burrowing Parrots (Cyanoliseus patagonus), located in Patagonia, Argentina. Counts during the 2001–02 breeding season showed that the colony extended along 9 km of a sandstone cliff facing the Altantic Ocean, in the province of Río Negro, Patagonia, Argentina, and contained 51412 burrows, an estimated 37527 of which were active. To our knowledge, this is largest known colony of Psittaciformes. Additionally, 6500 Parrots not attending nestlings were found to be associated with the colony during the 2003–04 breeding season. We monitored activities at nests and movements between nesting and feeding areas. Nestlings were fed 3–6 times daily. Adults travelled in flocks of up to 263 Parrots to the feeding grounds in early mornings; later in the day, they flew in smaller flocks, making 1–4 trips to the feeding grounds. Overall, the most frequent flock size was two, indicating that the pair is the basic social unit during the breeding season. The average flight-speed was 36.9 km h–1. Terrestrial and aerial surveys during the 2003–04 and 2004–05 breeding seasons suggest that Burrowing Parrots performed long daily movements in order to feed in the remaining patches of natural vegetation, travelling 58 and 66 km over the two main routes to the feeding areas. The colony is seriously threatened by human activity, and surrounding habitat is being rapidly transformed to agricultural land. Based on the data presented, we recommend monitoring the colony using detailed counts of numbers of nests, the documentation of the extent of the entire colony, together with data on breeding success, nestling growth and feeding rates. The number of non-breeders associated with the colony should be monitored, and as an additional index of abundance, counts from stationary locations should be continued.Facultad de Ciencias Naturales y Muse

Behavioural plasticity in the early breeding season of pelagic seabirds - a case study of thin-billed prions from two oceans.

Background:In long-lived seabirds that migrate large distances independently of each other, the early part of the breeding season is crucially important for a successful reproductive attempt. During this phase, pair bonds are re-established and partners coordinate their breeding duties. We studied the early breeding season in Thin-billed prions Pachyptila belcheri breeding in the Atlantic Ocean (Falkland/Malvinas Islands) and Indian Ocean (Kerguelen). Despite overlap in the wintering areas, these two populations exhibit differences in their timing and direction of migration. We hypothesised that these differences would influence behaviour during the early breeding season. Results:In line with our hypothesis, we found very strong differences in colony attendance patterns. Thin-billed prions of the Falkland population spent the late winter period over shelf waters close to the colony, first arrived back at the colony in September, and attended the nests interruptedly for one month, before departing on a pre-laying exodus. In contrast, Kerguelen birds remained in the non-breeding areas until mid-October and spent much less time attending the burrow before their pre-laying exodus. Despite this asynchronous arrival to the two colonies, the subsequent patterns resulted in remarkably synchronous incubation in both populations, with males taking on the first long incubation shift in late November, whereas females returned to sea soon after egg laying. During the pre-laying exodus and incubation, Thin-billed prions from the Falklands spread north over the Patagonian Shelf, while prions from Kerguelen travelled much further, reaching southern oceanic waters and moved at faster speeds (&gt; 400 km per day). Although prions from Kerguelen moved much further, their isotopic niches were considerably narrower, suggesting a stronger dependence on Antarctic waters. Conclusions:The study thus suggests that Thin-billed prions show a high intraspecific plasticity in their use of either neritic or oceanic waters during the early breeding season. Breeding birds from the Falkland Islands can exploit an extensive shelf area, while Kerguelen birds have adapted to the need to forage in distant southern open waters. This difference in foraging ecology may thus have shaped the phenology of the early breeding phase

Ornamental non-carotenoid red feathers of wild burrowing parrots

Bird plumage colors have the potential to indicate individual quality, condition, health, immunocompetence, or the extend of parental care. Color intensity of feathers has been found to correlate with parameters of individual quality, condition, parental care and breeding success. Psittaciformes are well known for their colorful plumage but the significance of parrot coloration is still poorly understood. Red colors are very common in many parrot species. They are produced by at least four non-carotenoid-based pigments (linear polyenal structure). In the present study, we investigated a collection of red abdominal feathers of a marked population of wild Burrowing Parrots Cyanoliseus patagonus in Patagonia, Argentina. The aims of this study were to investigate the ecological significance of the recently described non-carotenoid-based red pigments of Psittaciformes, and the relationships between objectively assessed plumage color and body size, body condition, breeding success and nestling growth in wild Psittaciformes. We found that sexes differed in plumage coloration (sexual dichromatism), that plumage color was a good predictor of female body condition and male size, and we identified the red coloration of the abdominal patch as a signal of individual quality and parental investment.Facultad de Ciencias Naturales y Muse

The high Andes, gene flow and a stable hybrid zone shape the genetic structure of a wide-ranging South American parrot

<p>Abstract</p> <p>Background</p> <p>While the gene flow in some organisms is strongly affected by physical barriers and geographical distance, other highly mobile species are able to overcome such constraints. In southern South America, the Andes (here up to 6,900 m) may constitute a formidable barrier to dispersal. In addition, this region was affected by cycles of intercalating arid/moist periods during the Upper/Late Pleistocene and Holocene. These factors may have been crucial in driving the phylogeographic structure of the vertebrate fauna of the region. Here we test these hypotheses in the burrowing parrot <it>Cyanoliseus patagonus </it>(Aves, Psittaciformes) across its wide distributional range in Chile and Argentina.</p> <p>Results</p> <p>Our data show a Chilean origin for this species, with a single migration event across the Andes during the Upper/Late Pleistocene, which gave rise to all extant Argentinean mitochondrial lineages. Analyses suggest a complex population structure for burrowing parrots in Argentina, which includes a hybrid zone that has remained stable for several thousand years. Within this zone, introgression by expanding haplotypes has resulted in the evolution of an intermediate phenotype. Multivariate regressions show that present day climatic variables have a strong influence on the distribution of genetic heterogeneity, accounting for almost half of the variation in the data.</p> <p>Conclusions</p> <p>Here we show how huge barriers like the Andes and the regional environmental conditions imposed constraints on the ability of a parrot species to colonise new habitats, affecting the way in which populations diverged and thus, genetic structure. When contact between divergent populations was re-established, a stable hybrid zone was formed, functioning as a channel for genetic exchange between populations.</p