How do birds evolve over generations? How do different bird populations diverge into new species? Ornithologists have been asking these questions since the days of Darwin, but rapid advances in genetic sequencing techniques in the last few years have brought answers more in reach than ever. A Review forthcoming in The Auk: Ornithological Advances describes some of the newest and most exciting developments in the field of “high-throughput sequencing,” a collection of techniques for studying broad regions of a genome rather than individual genes.

High-throughput sequencing has been dropping in cost and complexity; once only available to large research consortiums, these methods are now feasible for smaller labs that were previously limited to working with individual genes or with mitochondrial DNA. “It’s like going from seeing with a few light sensitive cells that can only detect the difference between night and day to a fully formed eye that can see all of the stars in the night sky,” says David Toews of the Cornell Lab of Ornithology, the lead author of the Review.

Because high-throughput sequencing data looks at many genes instead of just a few, it makes it easier to identify very subtle genetic differences between populations, such as the genetics underlying small differences in plumage patterns between different subspecies of Wilson’s Warbler. It can also provide a fresh look at the genetic changes that occur in “hybrid zones,” where the ranges of closely related species overlap and members of the species breed freely with each other, such as where Black-capped and Carolina Chickadees meet in Pennsylvania. The process of one species splitting into two, such as what may be happening with the coastal and inland subspecies of Swainson’s Thrush, is another intriguing area for study.

“Right now, genetic technology is advancing so fast that it is mind-boggling to keep up with the latest techniques, the questions that are becoming available to ask, and the answers that the data gives us,” says Jack Dumbacher of the California Academy of Sciences, an expert in bird molecular ecology who was not involved with the paper. “This is not only a review of what we are learning, but how we are learning it and what we need to be thinking about next. The paper should be a great source for students trying to figure out how to get into this complex field of modern ornithological genetics.”

“I think as the methods mature, so will the field—we are really in an exploratory stage with this data. I think once the questions and theory become more refined, we will be able to be more hypothesis-driven in the study of avian genomics,” adds Toews. “In the end, however, this is just a tool. I think the tool is a powerful one, but it is really in the application to interesting biological questions that the biggest advances will come.”

Genomic approaches to understanding population divergence and speciation in birds is available at http://www.aoucospubs.org/doi/full/10.1642/AUK-15-51.1. Contact: David Toews, toews@cornell.edu.

About the journal: The Auk: Ornithological Advances is a peer-reviewed, international journal of ornithology that began in 1884 as the official publication of the American Ornithologists’ Union. In 2009, The Auk was honored as one of the 100 most influential journals of biology and medicine over the past 100 years.

Birds stopping for a break during their grueling migratory flights face a difficult tradeoff: They need to fuel up with food as efficiently as possible, but they need to avoid predators while they do it. To learn more about how they make these choices about food availability and predator risk, Jennifer McCabe and Brian Olsen of the University of Maine’s Climate Change Institute spent two years capturing birds during fall migration along the coast of Maine. Their results, published in The Auk: Ornithological Advances, show that overall birds prefer to stop in habitat with plenty of dense vegetation in which they can hide from predators such as hawks. However, the longer the migration a bird is facing, the more likely it is to take risks in order to fill up with high-energy fruit.

The six sites they monitored in 2011 and 2012 on Maine’s coastal headlands and islands fell into two categories. At some, there was no conflict between food availability and shelter from predators—birds could get both at the same time. However, at others, birds could only access the best food resources by venturing out into the open. Over the course of their two-year study, McCabe and Olsen captured almost 10,000 birds belonging to 28 species, and they found that bird abundance was higher overall in sites that didn’t force a tradeoff. The authors speculate that migrants quickly assess a site’s safety and productivity, and if a tradeoff is required, they soon move on.

While previous studies had looked at how individual species responded to these competing pressures, McCabe and Olsen’s study is unique in that it encompassed all the fruit-eating migratory birds in the area. “The neatest aspect of the study was that we used the entire migratory community to look at tradeoffs between foraging and predator avoidance similarly to behavioral research on single species, and we found similar results at the community scale as single species studies did,” says McCabe.

Habitat patches that maximize both food availability and vegetation to hide in are not the same as the mature, intact forests many songbirds prefer to breed in. Instead, they tend to be in places such as brushy forest edges, and the authors recommend that if wildlife managers want to support birds during migration as well as the breeding season, this sort of habitat cannot be overlooked, even if it appears less than pristine.

“Hawks, primarily falcons, are found in large numbers on Maine’s coastal islands during fall migration, keying in on the songbirds on migration stopover in the region. McCabe and Olsen’s manuscript does a brilliant job of assessing the balance between risking predation and fueling the energy demands for migration at six bird-banding stations along the Maine coast,” according to Glen Mittelhauser of the Maine Natural History Museum. “Overall, a well-done study that has advanced our knowledge of migration tradeoffs between food and safety and got us thinking about the importance of food resources and microhabitat on these coastal islands.”

Tradeoffs between predation risk and fruit resources shape habitat use of landbirds during autumn migration is available at http://www.aoucospubs.org/doi/full/10.1642/AUK-14-213.1. Contact: Jennifer McCabe, jennifer.mccabe@maine.edu.

About the journal: The Auk: Ornithological Advances is a peer-reviewed, international journal of ornithology that began in 1884 as the official publication of the American Ornithologists’ Union. In 2009, The Auk was honored as one of the 100 most influential journals of biology and medicine over the past 100 years.

Common Loons (Gavia immer) nest on lakes across Canada and the northern U.S., but every winter they disperse, many to the open ocean where they’re difficult to track. It’s been well established that many loons return to the same nesting sites every spring, but new research in The Condor: Ornithological Applications shows for the first time that they are similarly faithful to their wintering sites. Over the course of nearly 15 years, James Paruk of the Biodiversity Research Institute and his colleagues used a combination of methods to investigate winter site fidelity at four locations across North America and found that birds had an 85% chance of returning to a site in subsequent years. Because loons’ coastal wintering habitats can be severely impacted by oil spills and other human activities, this information has important implications for wildlife managers.

Common Loons have an enormous winter range, including nearly all of North America’s coastlines as well as some large freshwater reservoirs. Paruk and his colleagues collected data at four sites spread across the continent, three on the coasts of Maine, Louisiana, and California and one at an inland reservoir in Washington. In Louisiana, California, and Washington they captured loons and gave them leg bands in unique color patterns so they could recognize individuals and determine which ones came back, while in Maine they outfitted loons with satellite transmitters. Both methods showed the same result: the birds had a high probability of returning to the same wintering sites year after year.

The researchers speculate that loons benefit from the local knowledge they gain from returning to the same area again and again; they can learn the best spots to find food and hide from predators, which can be especially important for loons in winter. Adult loons go through a molt in winter that leaves them temporarily unable to fly, making it especially important to select a good site to spend the winter.

“Our finding was one of the last key unknowns about Common Loon natural history, and it was good to get some solid data on this topic,” says Paruk. Collecting that data, however, was something of an adventure. “While catching loons in 2014, I was at the bow, and the captain called to me to pick up a buoy-type bottle bobbing in the ocean. As we approached, I leaned over the bow and picked it up, and just beneath, and scaring the daylights out of me, was a four-foot sand shark! It just missed me, and made me feel quite out of my element.”

A number of marine oil spills have impacted Common Loon wintering habitat in recent decades, and the more loons return to the same contaminated areas, the more their breeding success and ability to survive could be affected by chronic exposure. For conservationists, this new piece of information about the life history of loons could be an important key for keeping populations healthy, so that these iconic birds can continue to knit together forest lakes and far-flung coasts for a long time to come.

Winter Site Fidelity and Winter Movements in Common Loons (Gavia immer) Across North America is available at http://www.aoucospubs.org/doi/full/10.1650/CONDOR-15-6.1. Contact: James Paruk, jim.paruk@briloon.org.

About the journal: The Condor: Ornithological Applications is a peer-reviewed, international journal of ornithology. It began in 1899 as the journal of the Cooper Ornithological Club, a group of ornithologists in California that became the Cooper Ornithological Society.

Birds of a feather may flock together, but that doesn’t mean they share a genetic background. Though birds were first classified into groups primarily based on appearance, research forthcoming in The Auk: Ornithological Advances by Brett Benz of the American Museum of Natural History, Mark Robbins of the University of Kansas Biodiversity Institute, and Kevin Zimmer of the Los Angeles County Museum of Natural History demonstrates that this method isn’t necessarily accurate: in a group of very similar-looking South American woodpecker species, genetic analysis has now shown one to be only a distant cousin of the others, in an intriguing case of visual mimicry. By copying the appearance of larger, socially dominant woodpecker species, it reduces the aggression and competitive interference that it receives from them and has more access to food resources as a result.

The most familiar type of mimicry typically involves warning or “aposematic” coloration, in which a harmless species apes the color patterns of a dangerous or unappealing one to avoid predators; a famous instance is the Viceroy butterfly, which shares the striking colors of the more noxious Monarch. By contrast, the Helmeted Woodpecker (Dryocopus galeatus) represents an example of a different and less well understood form of mimicry, known as interspecific social dominance mimicry or ISDM.

The shy and little-known species shares the red crest, black back, and barred underside of two larger woodpeckers, Dryocopus lineatus and Campephilus robustus, all of which occupy the same habitat and share similar food preferences. The Helmeted Woodpecker’s similarity in appearance makes the larger, more dominant woodpecker species less likely to attack it, due to the costs of aggression between members of the same species. Though they had been previously classified in Dryocopus due to the remarkable similarities in their appearance, genetic analysis by Benz and his colleagues suggests that the Helmeted Woodpecker is actually not closely related to other Dryocopus woodpeckers at all and belongs in a different genus, Celeus. An independent group of researchers using the same data recently reported similar results in a paper published in the Journal of Ornithology.

“Co-author Mark Robbins and I had just finished a phylogenetic study examining species limits and vocalizations in Celeus woodpeckers when Mark, who was attending a meeting in Brazil, had the opportunity to observe a Helmeted Woodpecker at Intervales State Park,” according to Benz. “Upon hearing the bird vocalize, Mark was stunned that its call sounded nothing like Neotropical Dryocopus, and immediately knew we needed to examine its taxonomic status in the context of our recent Celeus study given that the Helmeted Woodpecker calls were most similar to several other Celeus species. Upon returning from Brazil, Mark consulted with co-author Kevin Zimmer, who had independently arrived at the same conclusions about the Helmeted Woodpecker belonging with Celeus, based on his behavioral observations spanning 20 years of fieldwork in Brazil.” As Benz puts it, “The Helmeted Woodpecker is basically a typical Celeus in Dryocopus clothing.”

“After several decades working on the discovery of the avian Tree of Life, it is still amazing what we are discovering! Reconstructing the phylogeny of these woodpeckers has corrected a century-old classification mistake, but more interestingly, it has revealed an unexpected new example of avian mimicry,” adds Richard Prum of Yale University, one of the originators of the ISDM hypothesis. “It has only recently been appreciated that small species may benefit from deceptively mimicking larger species to protect themselves from aggressive attack. This is similar to how a 12-year-old kid walking home from school will look and act tough to try to prevent himself from being harassed by older, bigger kids.”

Relatively little is known about the ecology and natural history of the Helmeted Woodpecker, which is found in Brazil, Paraguay, and Argentina, but it has experienced dramatic population declines and vanished from much of its former range due to deforestation. Hopefully, this new discovery about its evolutionary relationships and visual deception may increase interest in the species, as it provides an opportunity for scientists to further test predictions associated with ISDM. Ultimately, bringing the Helmeted Woodpecker’s sneaky strategy into the light may be what saves it from oblivion.

Phylogenetic relationships of the Helmeted Woodpecker (Dryocopus galeatus): A case of interspecific mimicry? will be published on September 30, 2015, and will be available at http://www.aoucospubs.org/toc/tauk/132/4; a pre-print version is available at http://dx.doi.org/10.1101/023663. Contact: Brett Benz, bbenz@amnh.org.

About the journal: The Auk: Ornithological Advances is a peer-reviewed, international journal of ornithology that began in 1884 as the official publication of the American Ornithologists’ Union. In 2009, The Auk was honored as one of the 100 most influential journals of biology and medicine over the past 100 years.

(July 22, 2015, The Auk: Ornithological Advances)—Animal populations on islands tend to develop weird traits over time, becoming big (like Galapagos tortoises) or small (like extinct dwarf elephants) or losing the ability to fly (like the flightless parrots of New Zealand). One less-studied pattern of evolution on islands is the tendency for animal populations to develop “melanism”—that is, dark or black coloration. J. Albert Uy and Luis Vargas-Castro of the University of Miami found an ideal species to study this phenomenon in the Chestnut-bellied Monarch (Monarcha castaneiventris), a bird found in the Solomon Islands. Most have the chestnut belly suggested by their name, but in the subspecies found in the Russell Islands, a few all-black birds coexist with the chestnut-bellied majority. After visiting 13 islands of varying sizes to survey their Chestnut-bellied Monarch populations, Uy and Vargas-Castro confirm in a new paper published this week in The Auk: Ornithological Advances that island size predicts the frequency of melanic birds, with populations on smaller islands including more dark individuals.

Because the pattern is repeated on island after island, it is very unlikely to have developed through random chance; instead, dark coloration must provide some sort of benefit to birds on small islands. Studies in mammals and fish have found a genetic link between melanism and aggressive behavior, and Uy and Vargas-Castro speculate that the limited space available on smaller islands makes competition for breeding territories more intense, giving an advantage to the most aggressive individuals. Previous experiments with other Monarcha castaneiventris subspecies using taxidermied birds and recorded songs have shown that melanic birds react more aggressively than their chestnut-bellied counterparts when they perceive a threat to their territory.

Uy had been fascinated by Chestnut-bellied Monarchs ever since reading a description of their plumage variations in Ernst Mayr’s seminal book on speciation, Systematics and the Origin of Species from a Viewpoint of a Zoologist, when he was a graduate student. “I was hooked and longed to work on the group,” he says. “I thought this would be the perfect species to explore these questions about the ecology of plumage diversification and the origin of species, as the variable populations of the chestnut-bellied flycatcher may be at different stages of the speciation process. It took me over a decade to finally manage to get to the Solomons, and I’ve been working on these flycatchers now for nearly 10 years.”

“Patterns of biodiversity on islands have always been important for understanding fundamental principals in ecology and evolution. Using the same archipelago that enchanted Ernst Mayr decades ago, Uy and Vargas-Castro reveal fascinating patterns of melanism and island size,” adds Rebecca Safran of the University of Colorado, an expert on divergence between bird populations who was not involved in the study. “These patterns add to the fundamental importance of islands as natural experiments for studies in biodiversity.”

Island size predicts the frequency of melanic birds in the color-polymorphic flycatcher Monarcha castaneiventris of the Solomon Islands is available at http://www.aoucospubs.org/doi/full/10.1642/AUK-14-284.1. Contact: J. Albert Uy, uy@bio.miami.edu.

About the journal: The Auk: Ornithological Advances is a peer-reviewed, international journal of ornithology that began in 1884 as the official publication of the American Ornithologists’ Union. In 2009, The Auk was honored as one of the 100 most influential journals of biology and medicine over the past 100 years.

(July 22, 2015, The Condor: Ornithological Applications)—Reintroducing a species into an area where it has vanished can be a great tool for conservation, but for reintroduction to be successful it’s crucial to understand how the habitat has changed in the interim and whether the reintroduced species will be able to thrive in its former home. Extirpated in the 1960s as a result of human activity, Bald Eagles (Haleiaeetus leucocephalus) have been reintroduced to California’s Channel Islands over the last 35 years. A study published this week in The Condor: Ornithological Applications examined the diets of these reestablished eagles in 2010 and 2011 to see how they compared to the diets of historical population. Like historical eagle populations, the reintroduced eagles in the Northern Channel Islands rely heavily on seabirds, according to authors Seth Newsome of the University of New Mexico, Paul Collins of the Santa Barbara Museum of Natural History, and Peter Sharpe of the Institute for Wildlife Studies. They also found that eagles on nearby Santa Catalina Island eat mostly fish, likely due to differences in human activity and a lack of seabird colonies on the island.

Newsome and his colleagues used two independent approaches to see what the eagles were eating—they collected the remains of prey from eagle nests, and they analyzed carbon and nitrogen isotopes in the eagles’ feathers. The isotope findings were then compared to those from potential prey to determine what animals the eagles were eating. Both methods found the same results. “Generally speaking, the northern islands are much more pristine, and a larger fraction of their coastlines includes areas where fishing is strongly regulated or banned. Santa Catalina, on the other hand, has a larger human footprint, especially in the form of recreational fishing,” explains Newsome. “We believe that the differences in diversity of fish consumed by eagles in these two areas is actually a product of recreational fishing, and that eagles on Santa Catalina have learned to follow recreational fishing boats and scavenge discards thrown overboard.”

The Northern Channel Islands eagles’ reliance on seabirds shows that successful seabird conservation efforts in the region have had benefits across the ecosystem. “As a community ecologist, I feel that the re-establishment of species at all trophic levels, including top predators like Bald Eagles, is the ultimate goal for animal conservation,” says Newsome. “Preserving diversity is wonderful, but you need to preserve diversity at all levels in the food chain. At present, such intact fully-functioning food webs are relatively rare in the United States, but to see that happen in a place like the Channel Islands that is adjacent to an area with one of the highest human population densities in the U.S. (southern California) is exciting.”

The number of eagles currently nesting on the islands is still below historic levels, so this fledgling population likely has room to expand. Exploiting both historical food sources and new ones made available by human activity, Channel Islands eagles are a success story for ecosystem recovery.

Foraging ecology of a reintroduced population of breeding Bald Eagles on the Channel Islands, California, USA, inferred from prey remains and stable isotope analysis is available at http://www.aoucospubs.org/doi/full/10.1650/CONDOR-14-213.1. Contact: Seth Newsome, newsome@unm.edu.

About the journal: The Condor: Ornithological Applications is a peer-reviewed, international journal of ornithology. It began in 1899 as the journal of the Cooper Ornithological Club, a group of ornithologists in California that became the Cooper Ornithological Society.

(June 17, 2015, The Auk: Ornithological Advances)—Among birds, the line between species is often blurry. Some closely related species interbreed where their ranges overlap, producing hybrid offspring that can even backcross with either parent species, until a whole population of mixed-species birds forms in the area and creates what’s known as a “hybrid zone.” In the coastal marshes of New England, this has been happening between two sparrows—Saltmarsh Sparrow and Nelson’s Sparrow. A new study published this week in The Auk: Ornithological Advances shows that appearance alone is not enough to identify these hybrid zone birds: there is no single, intermediate “phenotype” or physical appearance common to all of the first-generation hybrids found, and birds from further backcrossed generations were often indistinguishable from the parent species. Fifty percent of birds identified as “pure” Nelson’s or Saltmarsh Sparrows in the field turned out be the descendants of hybrids when their DNA was analyzed.

Jennifer Walsh and Adrienne Kovach of the University of New Hampshire, along with Gregory Shriver of the University of Delaware, Brian Olsen of the University of Maine, and Kathleen O’Brien of the U.S. Fish and Wildlife Service, collaborated on this project to capture and examine the birds in the hybrid zone on the coast of Maine, New Hampshire, and Massachusetts. Each bird was classified based on its appearance as a Saltmarsh Sparrow, Nelson’s Sparrow, or a hybrid, and then a blood sample was taken so that the accuracy of this identification could be double-checked with DNA.

“Hybridization between species is quite common in birds and we often assume that the hybrids are going to be obvious intermediates between parental species. By combining detailed data on each bird’s appearance with genetic data that clearly identifies hybrids, Walsh and her colleagues have nicely demonstrated that the world is much more complex and that, in the case of these sparrows, the number of hybrids is much higher than we previously knew. This result is particularly relevant given the threats that saltmarsh nesting birds currently face,” says Chris Elphick of the University of Connecticut, an expert on tidal marsh birds who was not involved with the study.

Walsh and her colleagues recommend that future studies of hybrid zone birds need to include DNA sampling to confirm field identifications. Both species are considered high priorities for conservation in the region, and the Saltmarsh Sparrow in particular is considered globally vulnerable to extinction. In order to ensure that both species have a secure future, the first step is making sure we know for certain which is which.

“Sampling for this study was a big undertaking,” says Walsh, who carried out the study as part of her Ph.D. work. “We sampled 34 sites, spanning about 750 km. Traveling to and accessing all the sites was logistically challenging and we had a lot of support from USFWS and other conservation partners. Every marsh is hugely different in terms of bird density and accessibility. You never really know what to expect until you get there—some days we would trap 10 birds in 2 hours, some days we would trap 2 birds in 12 hours! In general, salt marshes are challenging too—there are a lot of holes and mud and ditches, and you are always working around the tides. It is amazing how quickly the marsh changes—very accessible at low tide, but at high tide you can find yourself swimming back.”

Saltmarsh Sparrows (shown) produce hard-to-identify hybrids with Nelson’s Sparrows. Image credit: K. Papanastassiou

Relationship of phenotypic variation and genetic admixture in the Saltmarsh–Nelson’s sparrow hybrid zone is available at http://www.aoucospubs.org/doi/full/10.1642/AUK-14-299.1. Contact: Adrienne I. Kovach, adrienne.kovach@unh.edu.

About the journal: The Auk: Ornithological Advances is a peer-reviewed, international journal of ornithology that began in 1884 as the official publication of the American Ornithologists’ Union. In 2009, The Auk was honored as one of the 100 most influential journals of biology and medicine over the past 100 years, and it currently holds the top impact factor among ornithological journals.

(June 10, 2015, The Condor: Ornithological Applications)—We all like things that are bad for us sometimes, and birds are no different. When a bird or other animal makes choices that are actually harmful for it, by reducing their lifespan, reproductive success, or something else, this is known as an “evolutionary trap.” If birds prefer to build their nests in non-native plant species but these nests are less successful, they’ve fallen into such a trap. A group of researchers recently set out to determine whether this is the case for Veeries (Catharus fuscescens) nesting in invasive shrubs in the forests of New York.

Lydia Meyer and Bruce Robertson of Bard College, along with Kenneth Schmidt of Texas Tech University, monitored 84 Veery nests during the spring 2013 breeding season in a forest where invasive shrubs such as Japanese honeysuckle, barberry, and multiflora rose are abundant. They recorded a variety of characteristics related to nests’ location, including nest height and visibility, the type of plant a nest was placed in, and the type of vegetation within a 5-meter radius around the nest. Their results, published this week in The Condor: Ornithological Applications, show that while these Veeries did prefer to locate their nests in non-native plants, this choice didn’t hurt their nesting success at all.

“While it is disappointing that exotic understory plants are displacing their native counterparts in forests throughout the Northeastern U.S., it is encouraging to see that at least one native bird is able to find that these exotic replacements also make safe locations to place a nest,” says study author Bruce Robertson. The Veeries’ choice to nest in non-native shrubs wasn’t bad for them after all—instead, they were just taking advantage of a new suitable habitat.

“Meyer et al. provide a critical test of whether non-native plant species can act as ecological traps for nesting birds. Nest site preferences in birds evolve over time based upon nest survival rates in different habitats, and may be confounded by the novel cues introduced by non-native plants,” adds Anna Chalfoun of the University of Wyoming, an expert on wildlife–habitat relationships. “Interestingly, in the example of the Veery, Meyer et al. conclude that parents were able to exploit the novel nesting sites provided by non-native plants, with no apparent effects on the probability of nest survival.”

About the journal: The Condor: Ornithological Applications is a peer-reviewed, international journal of ornithology. The journal began in 1899 as the journal of the Cooper Ornithological Club, a group of ornithologists in California that became the Cooper Ornithological Society.

(The Condor: Ornithological Applications, May 6, 2015)—Shifting to renewable energy sources has been widely touted as one of the best ways to fight climate change, but even renewable energy can have a downside, as in the case of wind turbines’ effects on bird populations. In a new paper in The Condor: Ornithological Applications, a group of researchers demonstrate the impact that one wind energy development in Kansas has had on Greater Prairie-Chickens (Tympanuchus cupido) breeding in the area. Virginia Winder of Benedictine College, Andrew Gregory of Bowling Green State University, Lance McNew of Montana State University, and Brett Sandercock of Kansas State University monitored prairie-chicken leks, or mating sites, before and after turbine construction and found that leks within eight kilometers of turbines were more likely to be abandoned.

Leks are sites at which male prairie-chickens gather each spring to perform mating displays and attract females. The researchers visited 23 leks during the five-year study to observe how many male birds were present and to record the body mass of trapped males. After wind turbine construction, they found an increased rate of lek abandonment at sites within eight kilometers of the turbines as well as a slight decrease in male body mass. Lek abandonment was also more likely at sites where there were seven or fewer males and at sites located in agricultural fields instead of natural grasslands.

This paper is the latest in a series of studies on the effects of wind energy development on prairie-chickens. “To me, what is most interesting about our results is that we are now able to start putting different pieces of our larger project together to better understand the response of Greater Prairie-Chickens to wind energy development at our field site,” says study co-author Virginia Winder. “We have found that both male and female prairie-chickens have negative behavioral responses to wind energy development. The data we collected to monitor this response have also allowed us new insights into the ecology of this species. For example, lek persistence at our study site depended not only on distance to turbine, but also male numbers and habitat.”

The findings of this study reinforce the U.S. Fish and Wildlife Service recommendation that no new wind energy development should be done within an eight-kilometer buffer around active lek sites. “It is critical to have rigorous evaluations of direct and indirect effects of wind energy facilities on species such as prairie-chickens,” according to grassland wildlife management expert Larkin Powell, who was not involved with the research. “The potential for trade-offs between renewable energy and wildlife populations on the landscape is one of the key questions of our day.”

Responses of male Greater Prairie-Chickens to wind energy development is available at http://www.aoucospubs.org/doi/full/10.1650/CONDOR-14-98.1. Contact: Brett Sandercock, bsanderc@ksu.edu.

About the journal: The Condor: Ornithological Applications is a peer-reviewed, international journal of ornithology. The journal began in 1899 as the journal of the Cooper Ornithological Club, a group of ornithologists in California that became the Cooper Ornithological Society.

(May 6, 2015, The Auk: Ornithological Advances)—How to protect your chicks from predators? Build a dome over them! There is tremendous diversity among the nests of birds, in nest location, structure, materials, and more, but we know very little about the forces that shaped the evolution of this incredible variety. In a new paper published this week in The Auk: Ornithological Advances, Zachary Hall, Sally Street, Sam Auty, and Susan Healy of the University of St. Andrews in Scotland test the hypothesis that domed-shaped nests arose as a result of some species transitioning to nesting on the ground, where the risk from predators is greater.

Hall was completing his Ph.D. work on the neurobiology of nest-building behavior when he noticed that very little work had been done on trying to understand why different bird species build such drastically different nest structures. “I thought this was strange,” he explains, “because the shape of a nest seems to be the most striking and diverse feature across bird species.” The hypothesis that dome-shaped nests resulted from the increased predation risk when competition for nest sites led some birds to begin nesting on the ground was first proposed almost twenty years ago, but techniques at the time did not provide a way to test it. Applying statistical techniques he had previously used in his neurobiology study, Hall and his colleagues collected previously published descriptions of the nests of 155 species of babbler and mapped nest height and structure to the birds’ family tree.

Their analysis confirmed that babblers’ ancestors likely built above-ground, cup-shaped nests, and that the addition of a dome to cover the nest corresponded with switching to nesting at ground level. “This new study by Hall, Street, Auty, and Healy looks at the evolution of two key aspects of animals as architects: how they shape their homes and where they put them. It shows very nicely how we can take advantage of recent progress in avian phylogenetics to test ideas about the evolutionary history behind the modern-day co-occurrence of particular pairs of traits,” according to Don Dearborn, an expert in the evolution of reproductive strategies in birds. “I am very happy how well nest structure integrated into our analyses, but this study is only the tip of the iceberg, and we hope future work can use a similar approach to identify other factors that may have influenced the evolution of nest structure,” adds Hall.

The coevolution of building nests on the ground and domed nests in Timaliidae is available at http://www.aoucospubs.org/doi/full/10.1642/AUK-15-23.1. Contact: Zachary J. Hall, zach.hall@utoronto.ca.

About the journal: The Auk: Ornithological Advances is a peer-reviewed, international journal of ornithology. The journal has been the official publication of the American Ornithologists’ Union since 1884. In 2009, The Auk was honored as one of the 100 most influential journals of biology and medicine over the past 100 years, and currently holds the top impact factor among ornithological journals.