AUTHOR BLOG: How the ‘Mitey’ Have Fallen: Impacts of Burrowing Skin Mites on Reproduction of an Urban Raptor

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Black Sparrowhawks displaying symptoms of mite infection.

Julia L. van Velden

Linked paper: Negative effect of mite (Knemidokoptes) infection on reproductive output in an African raptor by J.L. van Velden, A. Koeslag, O. Curtis, T. Gous, and A. Amar, The Auk: Ornithological Advances 134:3, July 2017.

Parasites were once considered to be one of the less important factors that limit or regulate animal populations, with the impacts of predators and resource limitation previously receiving far more attention. This lack of attention probably stemmed from the mistaken belief that most parasites have evolved not to harm their hosts too much, because if their host dies, they lose the resource they depend on. We now know, however, that parasites can often strongly affect both a host’s reproduction and survival rates. Our new study published in The Auk: Ornithological Advances adds to this knowledge for a relatively understudied parasite in a wild raptor population.

Knemidokoptes mites are a genus of microscopic skin mites which burrow into the skin of birds and cause the “scaly leg” and “scaly face” conditions that are frequently seen in caged and domestic birds. They also occur in some wild species, particularly passerines. However, these parasites have rarely been recorded on raptors, except on captive birds. Additionally, almost no research has been carried out to investigate the impacts of these parasites on species’ fitness. Our study explored the symptoms of infection and the impact these mites have on the breeding performance of a wild population of Black Sparrowhawks in Cape Town, at the southernmost tip of South Africa.

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Knemidokoptes skin mites.

Black Sparrowhawks are a recent colonist to this mostly urban area, and urban living may come with associated changes in exposure to parasites and pathogens. Our study population has been closely monitored since 2001 and has grown steadily over the years, with the population now containing around 50 breeding pairs each year. In 2007, we started to notice birds in the population with strange symptoms, namely balding heads and scaly lesions on their legs. These birds appeared to be agitated and in poor condition. Post-mortem investigations revealed that, in all cases, birds with these symptoms were infected with the burrowing skin mite (Knemidokoptes spp.). We found that in some years, up to 5% of the Cape Peninsula population was infected, which represents a highly novel finding for a wild population of raptors.

Comparing between the sexes, we also found that mite infection was more frequent for males than females. Higher parasitic infection of males has been found for several other studies in different parasites and may be the result of fundamental biological and behavioural differences. In our population, we suspect that Black Sparrowhawks may become infected by these mites from their prey, possibly domestic chickens, which are known to frequently be infected by Knemidokoptes mites. Like most Accipiters, Black Sparrowhawks pluck their prey before consumption, which may mean they have greater exposure to this parasite than other raptor species, and the fact that males are responsible for hunting throughout the breeding season may explain the male bias in infection.

Most importantly, we found that Black Sparrowhawks that were infected with these mites had considerably reduced breeding success. We compared breeding performance between infected and non-infected birds and also between birds pre- and post-infection. These analyses showed that infection reduced breeding performance by over 50%. This could be because adults become too agitated to incubate or hunt effectively following infection.

We also investigated if this infection was present anywhere else in South Africa and found four hotspots of infection. Three of the infection sites were cities, and thus infection by this mite may be associated with urbanization levels and the additional stresses this may incur. Other research has, however, not yet detected any negative effect of urbanisation on this species’ health.

Our study, the first on Knemidokoptes mites within a wild population of raptors, therefore suggests that this parasite could play a role in limiting the breeding performance of infected populations. Although Black Sparrowhawks are not a species of conservation concern, this study provides important information on the negative role such parasites can play in their host’s reproductive success, which will be important if this infection is found to occur in an endangered raptor species.

AUTHOR BLOG: Tracking Semipalmated Sandpiper Migration

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Photo credit: B. Winn

Stephen Brown

Linked paper: Migratory connectivity of Semipalmated Sandpipers and implications for conservation by S. Brown, C. Gratto-Trevor, R. Porter, E.L. Weiser, D. Mizrahi, R. Bentzen, M. Boldenow, R. Clay, S. Freeman, M.-A. Giroux, E. Kwon, D.B. Lank, N. Lecomte, J. Liebezeit, V. Loverti, J. Rausch, B.K. Sandercock, S. Schulte, P. Smith, A. Taylor, B. Winn, S. Yezerinac, and R.B. Lanctot, The Condor: Ornithological Applications 119:2, May 2017.

The Semipalmated Sandpiper (Calidris pusilla) is a small shorebird, most commonly seen on migration along the coastlines of the eastern United States. It is historically one of the most widespread and numerous shorebird species in the Western Hemisphere, breeding across the North American Arctic tundra, but major population declines have been documented in the core of the nonbreeding range in northern South America. Breeding populations have also declined in the eastern North American Arctic, but appear to be stable or increasing in the central and western Arctic. To help understand what is causing the declines and work toward conservation of this species, we set out to track migration routes and stopover sites using light-level geolocators, a relatively new technology which determines the bird’s position on earth by measuring the length and timing of daylight throughout the year. The major challenge to using these tags is that you have to catch the bird once to put on the geolocator and then again the next year to retrieve it, which requires finding the same bird again in the vast arctic tundra. Luckily, they tend to return to the same breeding areas the next year.

Our large group of 18 partner organizations worked collaboratively to carry out the study across the entire North American Arctic from Nome, Alaska, to Hudson Bay, and we attached 250 geolocators to birds by mounting expeditions to 8 different field sites. Our field crews faced challenging conditions, working in the Arctic where the weather is always unpredictable and where both grizzly bears and polar bears regularly visit field sites. We repeated expeditions the next year to each site, and recovered 59 of the units by recapturing birds. The treasure trove of data showed migration routes and stopover sites from the entire year in the life of each bird, and showed that birds breeding in the eastern Arctic wintered in northeastern South America. Birds from eastern Alaska and far western Canada wintered from Venezuela to French Guiana. Central Alaskan breeders wintered across a very wide range from Ecuador to French Guiana. Birds that bred in western Alaska wintered mainly on the west coasts of Central America and northwestern South America, outside the nonbreeding region in which population declines have been observed.

Our results confirm that Semipalmated Sandpipers that breed in the eastern Arctic and use the Atlantic Flyway also use the areas in South America where population declines have been detected, suggesting that declines may be concentrated in populations along the Atlantic Flyway and in the eastern Arctic. However, because some birds from sites as far west as Barrow, Alaska, also used the areas in northeastern South America where declines have occurred, further work is needed to localize the geographic areas used by declining populations, and therefore the potential causes for the declines. We identified several new stopover and wintering areas, where implementing conservation actions to preserve the habitats used by Semipalmated Sandpipers could contribute to protecting the species. We measured a larger impact of geolocators on return rates than has been observed for larger shorebirds, indicating that caution should be used when working with small shorebirds, and that potential new information gains from additional geolocator studies should be weighed against expected impacts on individual survival. Our data also provided new insights about how long birds stay at migration stopover sites, which will be useful to studies that measure and monitor the total size of populations using these sites. Understanding the connections between breeding, migration, and wintering areas for these populations of a widespread yet declining shorebird can help future studies identify the causes of declines and ensure the effectiveness of targeted conservation efforts.

AUTHOR BLOG: A New Look at Altitudinal Migration

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Alice Boyle

Linked paper: Altitudinal bird migration in North America by W.A. Boyle, The Auk: Ornithological Advances 134:2, April 2017.

I became a birder in my early 20s when I moved to Costa Rica to play in the Orquesta Sinfónica Nacional. I didn’t know many people at first, and my Spanish was, shall we say, a work in progress. When I left Canada, I was given a pair of binoculars and the (then) newly published “A Guide to the Birds of Costa Rica” by Stiles and Skutch. Armed with these tools, I would get on a bus headed in a different direction every time I had a day off from my music job. At first I managed to identify only a few of the dozens of species that would pass in riotous mixed flocks. Pretty soon I realized that I had to focus on looking and taking notes, only later to pore over the book to figure out what I had seen. While those evening book sessions were occasionally frustrating (“Dang… I should have checked if that flycatcher had one or TWO wing bars!”), I also enjoyed reading the eloquent descriptions of bird behavior and soon found myself engrossed in tropical natural history. One of the things that puzzled me from the start were descriptions of the seasonal migrations of birds within that tiny, lovely, benign country. I grew up in a place where bird migration seemed not only logical, but frankly the ONLY sensible thing to do in winter. But why would some birds move up and down mountains each year in a place where the weather is always warm and food hangs from the trees wherever you go?

This question ultimately became the topic of my PhD many years later, and I did get some satisfying answers (full details here). But one unsatisfactory aspect of my chosen topic was that few other researchers were asking similar questions in other parts of the world. What common themes from my tropical work might hold true for other regions? What about North American birds? How common are these altitudinal migrations in our mountains? What else is known about them? Finally, in this article, I have attempted to summarize that knowledge. It turns out that we have LOTS of birds in North America that make similar types of movements. In fact, roughly the same proportion of the North American avifauna migrate up and down mountains as does the Costa Rican avifauna—20% to 30% depending on how you count it. With the exception of the Himalayas, reports from other avifaunas seem consistent with this figure. The higher latitude of North America makes things interesting, creating varied combinations of seasonal movements along both elevational and latitudinal gradients, and several of the North American species make movements that stretch our tidy migration terminology in complex ways. There is a reason I had trouble as a grad student finding this literature, however. Much of the information, now summarized in the Birds of North America life history series, was originally reported in bird atlases, Masters theses, or dated natural history accounts. Furthermore, despite early naturalists’ interest in the topic, few authors have cared to document patterns or tried to understand causes of these movements in recent years.

Why might this be so? Part of the reason might have to do with geography; there are more ornithologists in the flatter and more populated eastern portion of the continent compared to the topographically complex west, and this fact may have steered our collective research interest in some way. Part might have to do with the perception that these are not “real” migrations. Certainly the short distances many altitudinal migrants traverse are not the jaw-dropping feats of athleticism displayed by Red Knots, Arctic Terns, or Blackpoll Warblers. But I argue that they are real in many important respects: they involve seasonal return movements between breeding and non-breeding areas on predictable schedules. The fact that such movements are often partial (not all birds migrate), facultative (not genetically hard-wired), and short-distance actually makes them more attractive subjects for many types of migration research. We have far better chances of determining what ecological conditions tip the cost-benefit balance toward migrating in species that have built-in control groups in the form of resident individuals. Furthermore, the more “messy” movements are undeniably a part of the rich diversity of strategies that animals use to cope with a constantly shifting environment. If we are to protect our avifauna for future generations, understanding these movements will be as important as understanding the marathon flights of the migration poster children. Perhaps this review will inspire a blossoming of interest in the birds who make mountains their home.

Find out more:
www.aliceboyle.net
On Twitter: @birdfiddler
Learn about what we do in the Boyle Lab by following our YouTube channel and Flickr stream

AUTHOR BLOG: Bringing Mitochondria into Species Concepts

Geoffrey Hill

Linked paper: The mitonuclear compatibility species concept by G.E. Hill, The Auk: Ornithological Advances 134:2, April 2017.

A couple of years ago I was at the Bentsen State Park hawk watch tower with a dozen other birders when the topic of species boundaries came up. No one knew me or that I was a professional ornithologist—I was deep undercover as a mediocre birder—so I just listened to the conversation. Someone suggested that the “experts” changed species boundaries periodically so that new field guides would have to be printed and bought. The not-so-subtle suggestion was that the checklist committee was in the pockets of powerful publishers. Then it was suggested that researcher elites manipulated the system to get government money. Everyone quickly reached consensus that both of these views were correct. From that conversation, it would seem that scientists have not been very effective at conveying to the public the rationale for changes to the checklist. But maybe a skeptical public is not surprising given that some professional ornithologists are also not enamored with how species boundaries of birds are demarcated. This uncertainty regarding what is or is not a species could simply reflect the reality that at the tips of the branches of the tree of life, species boundaries are nebulous. But I don’t think that is correct. I agree with Ernst Mayr’s conclusions that species are real and fundamental biological entities. I’m convinced that the problem with the current approach to assessing species boundaries lies in a poor understanding of the process of speciation leading to an incomplete and confused species concept.

I lived the first fifty years of my life without offering any opinion about the process of speciation or species boundaries, and I had no plans to ever wade into the morass. It was therefore quite unexpected when I fell head first into the deep end of the speciation controversy by proposing a new definition for how to define an avian species, published as an opinion piece in The Auk. This new speciation concept arose not from phylogeographic studies—the genesis of all previous species concepts—but from the study of mating patterns in relation to colorful feathers (see Hill and Johnson 2012). Sexual selection and speciation have always been closely associated topics in evolutionary biology, but what I realized about five years ago is that both of these fundamental evolutionary processes emerge as a necessary outcome of the critical need for coadaptation between mitochondrial and nuclear genes and that mitonuclear coadaptation is the foundation of any comprehensive species concept. Before I explain what I mean by “mitonuclear coadaptation,” however, I need explain current dogma for recognizing species.

Whether it is explicitly stated or not, decisions regarding species boundaries are based on a species concept, and the Biological Species Concept currently being followed by the American Ornithological Society checklist committee was proposed by Ernst Mayr about 75 years ago, long before the age of modern genomics. As a matter of fact, the current species concept was written before biologists even knew that mitochondria have DNA that is inherited independently from the nuclear DNA.

It turns out the knowing about mitochondrial DNA is very important because mitochondrial DNA codes for components of the electron transport system, which is the biochemical machine that generates most of the energy for birds, mammals, and other complex life. But mitochondria only carry a few genes—not nearly enough to code for the entire electron-transport system—so much of the system is encoded by nuclear DNA, with the products moving over to the mitochondria to co-function with the products of mitochondrial genes. Having two distinct genomes coding for components that have to work together in a fully coordinated manner means that these genomes have to be coadapted; put another way, the genes in the mitochondria and nucleus have to coevolve so that their products are matched in physical shape and complementary of function. When populations become isolated, their mitochondrial and nuclear genes can coevolve to be different than the coevolved mitochondrial and nuclear genes of any other population such that they cannot be mixed without incompatibilities and fitness loss. What I propose in my opinion paper is that it is uniquely coadapted sets of mitochondrial and nuclear genes that define a species and that make hybrid offspring resulting from pairings between species less viable, thereby maintaining species boundaries.

Currently, it is not possible to assess the mitonuclear compatibility of any two populations of birds, although by simple extrapolation of advancing technology we will soon have such capability. What we currently have is information on the mitochondrial genotype of many species of birds, including many populations that are potentially distinct species. I propose that uniquely co-adapted mitonuclear genotypes necessarily involve unique mitochondrial genotypes. Thus, mitochondrial genotype becomes an excellent and available proxy for species boundaries.

Many biologists already look to mitochondrial genotypes when assessing species status.  My theory simply provides stronger justification for placing more emphasis on mitochondrial genotypes and less emphasis on nuclear genotypes. Indeed, advocates of DNA barcoding assert that most species can be unambiguously diagnosed by mitochondrial gene sequence, and my theory potentially explains why.

As with any new idea, this hypothesis for the process of speciation and nature of species boundaries must be tested. Whether the mitochondrial compatibility species concept proves to be accurate or an overstatement, ornithology will benefit by considering mitonuclear interactions when they ponder species boundaries.

AUTHOR BLOG: How Will an Arctic-Breeding Songbird Respond to Taller Shrubs and Warmer Temperatures?

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A female Smith’s Longspur solicits a mate. Photo credit: J. Hughey

Heather McFarland

Linked paper: Nest-site selection and nest success of an Arctic-breeding passerine, Smith’s Longspurs, in a changing climate by H.R. McFarland, S. Kendall, and A.N. Powell, The Condor: Ornithological Applications 119:1, February 2017.

How will songbirds that nest in tundra respond as the Arctic transforms into a warmer and shrubbier environment? This is the question that drove us to study a small songbird known as the Smith’s Longspur. Endemic to North America, this songbird breeds in only a few remote mountain valleys in Canada and Alaska, making it particularly susceptible to changes at northern latitudes. Smith’s Longspur’s are also unique in that they are polygynandrous. This is a rare mating strategy where both sexes are polygamous, and birds of either sex may mate with up to three individuals each breeding season. Rather than a single male and female establishing a territory, Smith’s Longspurs usually form larger groups called neighborhoods which contain many inter-mated individuals. Since this mating strategy is poorly understood and so different from other tundra nesting songbirds, it is difficult to predict how breeding Smith’s Longspurs may respond to climate change. Therefore, prior to further change, baseline information about breeding requirements is needed.

To fill this void, we monitored more than 250 Smith’s Longspur nests between 2007 and 2013 in the Brooks Range of Alaska. All of the nests were found in open tundra areas, and females never placed their nests in tall vegetation. Aside from a lack of tall shrubs, no specific habitat features that we measured influenced where females placed their nests. This finding is contrary to patterns commonly observed in monogamous ground-nesting birds where females tend to nest near a specific habitat feature. We believe that Smith’s Longspurs may deviate from this pattern because of their unique breeding strategy. Females may benefit more by nesting near other females where the chance of “hooking up” with additional males is greater. If this is the case, nest site selection may occur at a larger neighborhood scale. Considering these findings, we are concerned that future shrub growth in the Arctic could limit the amount of open tundra areas available for breeding neighborhoods of Smith’s Longspurs.

Although there may be fewer available nest sites in the future, warmer temperatures could benefit breeding Smith’s Longspurs. In this study, nests survived best when there were more warm days during the nesting period. Cold temperatures appeared to have no impact on nest success, possibly because females were able to delay nesting until weather conditions were favorable. During these years, females usually began nesting within a few days of one another, compared to years with good conditions early in the season when egg laying was spread out over several weeks. Considering that Smith’s Longspurs breed in the Arctic, it is not surprising that they have adapted strategies to withstand harsh conditions. Because of this adaptive ability, as well as the predicted increase in temperature throughout the Arctic, we believe that breeding Smith’s Longspurs could become more productive in the future. Even so, the combined outcome of reduced suitable habitat but potentially higher breeding productivity is still unknown. Continued monitoring of Smith’s Longspurs is needed as northern regions continue to change.

AUTHOR BLOG: Population-Specific Migration Patterns of Golden-Winged Warblers

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Gunnar Kramer

Linked paper: Nonbreeding isolation and population-specific migration patterns among three populations of Golden-winged Warblers by G.B. Kramer, H.M. Streby, Sean M. Peterson, J.A. Lehman, D.A. Buehler, P.B. Wood, D.J. McNeil, J.L. Larkin, and D.E. Andersen, The Condor: Ornithological Applications 119:1, February 2017.

Our study in The Condor: Ornithological Applications follows decades of research on the population dynamics of a declining songbird species, the Golden-winged Warbler.

Golden-winged Warblers have long been the focus of research and conservation interest due in part to sensationalized range-wide declines on the order of -2.5% per year; however, the true nature of these declines is more nuanced and complicated. When geographic populations are considered, Golden-winged Warblers demonstrate two very different stories. On one hand, the Appalachian population, breeding from Ontario through North Carolina and Georgia, experienced severe declines (up to -7% per year) over the past 50 years resulting in local extirpations and noticeable declines in the abundance and distributions of Golden-winged Warblers in the region. On the other hand, the western Great Lakes population, breeding largely in Minnesota, is home to ~50% of the global breeding population of Golden-winged Warblers and is maintaining historic population levels or possibly increasing over the past 50 years. When combined, these two very different stories blend into a general picture of overall population decline, spawning intensive efforts to identify breeding-grounds factors that might explain this decline, such as the loss of nesting habitat, poor nesting success, and competition with other closely related species (i.e., Blue-winged Warblers). Despite all the extensive research, no single breeding-grounds factor or combination of factors provides a parsimonious and consistent explanation for the differential population trends that exist in this species.

This is where our research comes in. Compared to the amount of research carried out in breeding populations of Golden-winged Warblers, relatively little has been done to link breeding populations to nonbreeding sites and identify migration routes in geographically isolated populations of Golden-winged Warblers. We developed a study to attach the smallest geolocators available (at the time in 2013 this was just under 0.50 g) to 9-10 g Golden-winged Warblers at multiple sites throughout their breeding distribution where they were experiencing variable population trends. Our main goal was simply to find out where these different populations went after they left the breeding grounds in North America and determine if the populations overlapped or occurred together in Central and South America during the nonbreeding period. If the declining Appalachian populations spent the winter in a region that was isolated from the stable western Great Lakes population, it is logical that the breeding-grounds population trends we observe might be caused at least in part by nonbreeding factors.

After all the hard work of redesigning the marking methods, getting the geolocators deployed, stressing over whether it would work, and then retrieving the geolocators, it was exciting to analyze the data and see entire year-long tracks of individual Golden-winged Warblers and to think about the distances these birds traveled and the places they spent their time when away from our study sites. We found that Golden-winged Warblers from Appalachian breeding populations spent the nonbreeding period in South America, mostly in a relatively small region on the border of Columbia and Venezuela. In contrast, Golden-winged Warblers from the western Great Lakes breeding population occurred throughout northern Central America in countries like Honduras, Nicaragua, Guatemala, Belize, and Mexico.

In the end, this geolocator study demonstrates a clear difference in nonbreeding locations and migration strategies among these different populations of Golden-winged Warblers. These differences are urgently meaningful from a conservation and management standpoint as they highlight a potential cause for regional differences in population trends observed across the breeding distribution. If nonbreeding factors are limiting Golden-winged Warbler population growth in the Appalachians, perhaps the most important implication of our work is to provide information that might help conservationists revise and refocus current strategies to better and target declining populations that spend the nonbreeding period in northern Colombia and Venezuela.

Read more at henrystreby.com.

AUTHOR BLOG: Cavity Nest Niche of the Endangered Vinaceous-Breasted Parrot: Sharing a Limited Resource Among Birds, Bees, and Opossums

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Photo credit: M. Lammertink

Eugenia Bianca Bonaparte and Kristina L. Cockle

Linked paper: Nest niche overlap among the endangered Vinaceous-breasted Parrot (Amazona vinacea) and sympatric cavity-using birds, mammals, and social insects in the subtropical Atlantic Forest, Argentina by E.B. Bonaparte and K.L. Cockle, The Condor: Ornithological Applications 119:1, February 2017.

Have you ever seen two animals fighting over a tree hole? Around the world, more than a thousand species of birds use tree holes or cavities for nesting, and they have to somehow share this critical resource with other birds, mammals, social insects, lizards and snakes. If two or more species of animals need cavities with similar characteristics, in the same place and at the same time of year, they overlap in nest niche. Nest niche overlap can lead to fierce competition for nest sites, lowering reproductive output and preventing the recovery of threatened species.

We got interested in how birds share the cavity resource because of our long-term work to conserve Vinaceous-breasted Parrots (Amazona vinacea), endangered cavity-nesters found only in the subtropical Atlantic Forest of South America. About 90% of the Atlantic Forest has already been converted to farmland, and nearly all the rest has been selectively logged, resulting in an extreme scarcity of nesting cavities. Vinaceous-breasted Parrots have declined throughout their range over the last century. In Argentina, where they were reported by early naturalists to “darken the sky” in “flocks of thousands,” less than 300 remain today. And this remnant population must share a dwindling supply of tree cavities with more than 70 other cavity-nesting species.

Our initial field work suggested that Vinaceous-breasted Parrots have low reproductive output. We wondered whether they might compete for nest sites with other species of birds, mammals, and social insects. On the other hand, theory and data from temperate forests suggested that cavity-nesting species reduce competition by partitioning the nest niche. For example, one species might use cavities high in the tree canopy, while another species uses cavities close to the ground. We reasoned that if such niche partitioning occurred in the Atlantic forest, we could identify specific cavity characteristics that we could then target for conservation of Vinaceous-breasted Parrots.

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Photo credit: M. Lammertink

To find out the extent of nest niche overlap among Vinaceous-breasted Parrots and co-occuring cavity-nesters, we studied timing of breeding, characteristics of cavities, trees, and habitat, and interspecific reuse of the same individual cavities, by large (> 140 g) birds and mammals (parrots, owls, toucans, forest-falcons and opossums) and social insects (bees and wasps). Every spring for 10 years, we shadowed adult birds, snooped on their eggs with our tiny pole-mounted spy cameras, and tested the limits of our tree-climbing equipment to access cavities up to 24 m high in the Atlantic Forest canopy.

Contrasting with reports from temperate forests, our data showed very little evidence of nest niche partitioning among cavity-nesters in a diverse subtropical community. Except for White-eyed Parakeets (Psittacara leucophthalmus), which nested later in the season, all bird species nested at the same time of year. Furthermore, and unfortunately for conservation efforts, no combination of cavity, tree and habitat characteristics was used exclusively by Vinaceous-breasted Parrots. Indeed, our models were unable to distinguish among the cavities used by the various species, and 8 of the 10 species reused each other’s cavities. The high level of overlap in nest niche, combined with previous evidence that cavities can limit bird density in our study area, support the idea that competition among species could play an important role in structuring the community of cavity nesters in the Atlantic Forest. Such competition could potentially inhibit the recovery of threatened species like Vinaceous-breasted Parrot.

What can be done for Vinaceous-breasted Parrots? Although we had little success classifying cavities by species, some characteristics of cavities, trees and habitat were selected more by Vinaceous-breasted Parrots than by other taxa, and we recommend targeting conservation efforts toward cavities and trees with these characteristics: >10 m high, entrance diameter 7–40 cm, tree diameter (DBH)>55 cm. Additionally, we found 62% of Vinaceous-breasted Parrot nests on farms (vs.≤50% for any other taxon), which highlights the importance of working with local farmers to conserve cavities in human-altered habitats as well as protected areas. As a start, through Proyecto Selva de Pino Paraná we organize outreach activities in schools and on farms, an annual parrot census, and a small scale reforestation program, all of which involve local farmers in the conservation of Vinaceous-breasted Parrots and their nest trees. We’re now busy interviewing farmers to study how they manage remnant native trees and what they think about cavity-nesting birds on their land. Stay tuned for the results!