Abstract View

Zootaxa 3694 (2): 131–142 (2 Aug. 2013)
Rediscovery and re-description of Ischnocnema nigriventris (Lutz, 1925) (Anura: Terrarana: Brachycephalidae)

Besides its brief original description in 1925 and information provided by one specimen collected in the 1980s, nothing else is known for Ischnocnema nigriventris (Lutz, 1925). Also, the poor preservation of the type series has hindered the association of this name with any known population of Ischnocnema. Fieldwork in Bertioga municipality, state of São Paulo, Brazil, revealed a population of Ischnocnema to which we were able to apply the name Ischnocnema nigriventris. We report this rediscovery, re-describe the species on the basis of the newly found specimens, and describe its mating call. Ischnocnema nigriventris is allocated to the Ischnocnema lactea species series and we propose a diagnosis based on a
combination of morphological character states. The species is diagnosed by prominent conical tubercles on the upper eyelid, inguinal region and hidden areas of the hind limbs with yellow mottling in males and orange mottling in females, and by its advertisement call composed of two to four non-pulsed notes, the first one differentiated from the others by its lower intensity and different frequency. Ischnocnema nigriventris is only known from Parque das Neblinas (Bertioga municipality), Paranapiacaba (Santo André municipality), and Boracéia (Salesópolis municipality), localities in the state of São Paulo, Brazil.

Zootaxa 3694 (2): 153–160 (2 Aug. 2013)
A new species of Satyrichthys (Teleostei: Peristediidae) from the Maldives Archipelago (Indian Ocean)

A new species of the genus Satyrichthys, Satyrichthys kikingeri sp. nov., is described from the Rasdhoo Atoll, Maldives Archipelago. The new species is placed in a group of Satyrichthys with at least three lip barbels and unequal parietal bones. It differs from its congeners in the combination of the following characters: (1) 3/3 lip and 1/0 chin barbels, (2) 15 fin rays in the second dorsal fin, 13 fin rays in the anal fin, (3) 25 bony plates in the dorsal, 29 in the upper lateral and 20 in the lower lateral rows, (4) 21st to 28th bony plates in the upper lateral row with forward directed spines and (5) parietal bones unequal in size on midline. Satyrichthys kikingeri sp. nov. is the first Satyrichthys species reported from the Republic of the Maldives.

Zootaxa 3694 (2): 161–166 (2 Aug. 2013)
Ompok karunkodu, a new catfish (Teleostei: Siluridae) from southern India

Ompok karunkodu, a new species of silurid catfish is described from the Amaravathi River, a right-hand tributary of the Kaveri [=Cauvery] River in Tamil Nadu, southern India. Ompok karunkodu can be distinguished from all congeners in the Indian subcontinent in having a markedly convex predorsal profile (vs. with a slight or distinct concavity in the supraethmoidal or supraoccipital region), and a unique combination of the following characters: prognathous lower jaw causing anterior profile of head to appear rounded when viewed laterally, maxillary barbel reaching to base of pectoral-fin spine,
eye diameter 13.7% HL, head width 13.0% SL, body depth at anus 14.2% SL, 65 anal-fin rays, caudal peduncle depth 5.0% SL, caudal-fin length 12.6% SL, caudal fin with rounded lobes, 54 vertebrae, and dark midlateral stripe running along sides of body.

Sandeep Sharma, Trishna Dutta, Jesús E. Maldonado, Thomas C. Wood, Hemendra Singh Panwar, John Seidensticker
Forest corridors maintain historical gene flow in a tiger metapopulation in the highlands of central India Proc. R. Soc. B September 22, 2013 280 1767 20131506; doi:10.1098/rspb.2013.1506 1471-2954

Understanding the patterns of gene flow of an endangered species metapopulation occupying a fragmented habitat is crucial for landscape-level conservation planning and devising effective conservation strategies. Tigers (Panthera tigris) are globally endangered and their populations are highly fragmented and exist in a few isolated metapopulations across their range. We used multi-locus genotypic data from 273 individual tigers (Panthera tigris tigris) from four tiger populations of the Satpura–Maikal landscape of central India to determine whether the corridors in this landscape are functional. This 45 000 km2 landscape contains 17% of India’s tiger population and 12% of its tiger habitat. We applied Bayesian and coalescent-based analyses to estimate contemporary and historical gene flow among these populations and to infer their evolutionary history. We found that the tiger metapopulation in central India has high rates of historical and contemporary gene flow. The tests for population history reveal that tigers populated central India about 10 000 years ago. Their population subdivision began about 1000 years ago and accelerated about 200 years ago owing to habitat fragmentation, leading to four spatially separated populations. These four populations have been in migration–drift equilibrium maintained by high gene flow. We found the highest rates of contemporary gene flow in populations that are connected by forest corridors. This information is highly relevant to conservation practitioners and policy makers, because deforestation, road widening and mining are imminent threats to these corridors.

Pietro Volta, Erik Jeppesen, Barbara Leoni, Barbara Campi, Paolo Sala, Letizia Garibaldi, Torben L. Lauridsen, Ian J. Winfield
Recent invasion by a non-native cyprinid (common bream Abramis brama) is followed by major changes in the ecological quality of a shallow lake in southern Europe
Biological Invasions September 2013, Volume 15, Issue 9, pp 2065-2079

We present an example of how an invasion by a non-native cyprinid (common bream, Abramis brama (Pisces: Cyprinidae), hereafter bream) in a natural shallow lake in southern Europe (Lake Montorfano, northern Italy) may have adversely affected the state of the lake’s ecosystem. In less than two decades, bream became the most abundant species and characterized by a stunted population with asymptotic length 33.5 cm, an estimated mean length at first maturity of 19.6 cm, a total mortality rate of 0.64 year−1 and a diet overwhelmingly dominated by microcrustaceans. Following bream establishment, nutrients and phytoplankton biomass rose, the proportion of Cyanobacteria by numbers increased markedly and water transparency decreased. Total zooplankton abundance increased with a marked increase in small cladocerans and copepods, whereas the abundance of large herbivorous cladocerans did not change. The coverage of submerged macrophytes declined, as did the abundance of native pelagic zooplanktivorous fish. The composition of the fish community shifted towards a higher proportion of zoobenthivorous species, such as bream and pumpkinseed (Lepomis gibbosus). Our results indicate that bream affected water quality through bottom-up mechanisms, while top-down effects were comparatively weak. Selective removal of bream and perhaps stocking of native piscivores might improve the ecological status of the lake.

Kirk W. Stodola, Eric T. Linder, Robert J. Cooper
Indirect effects of an invasive exotic species on a long-distance migratory songbird
Biological Invasions September 2013, Volume 15, Issue 9, pp 1947-1959

The loss of foundational tree species to non-native pests can have far reaching consequences for forest composition and function, yet little is known about the impacts on other ecosystem components such as wildlife. We had the opportunity to observe how the loss of eastern hemlock (Tsuga canadensis), due to the invasive hemlock woolly adelgid (Adelges tsugae), influenced the population ecology of the Black-throated Blue Warbler (Setophaga caerulescens) over a 7 year period. We followed the process of adelgid infestation and subsequent hemlock loss, which allowed us to investigate the patterns and mechanisms of population change. We document a precipitous decline in breeding pairs at one site where hemlock was most abundant in the understory, but not at our other two sites. We observed no changes in reproductive output or apparent survival, yet territory size increased dramatically at the most affected site, suggesting that the decline was due to a lack of colonization by new breeders. Our results demonstrate how an invasive insect pest can indirectly influence wildlife species not believed to be vulnerable and in ways not typically investigated.

Scriba MF, Ducrest A-L, Henry I, Vyssotski AL, Rattenborg NC, Roulin A. Linking melanism to brain development: Expression of a melanism-related gene in barn owl feather follicles covaries with sleep ontogeny. Frontiers in Zoology, published online July 26th, 2013
Intra-specific variation in melanocyte pigmentation, common in the animal kingdom, has caught the eye of naturalists and biologists for centuries. In vertebrates, dark, eumelanin pigmentation is often genetically determined and associated with various behavioral and physiological traits, suggesting that the genes involved in melanism have far reaching pleiotropic effects. The mechanisms linking these traits remain poorly understood, and the potential involvement of developmental processes occurring in the brain early in life has not been investigated. We examined the ontogeny of rapid eye movement (REM) sleep, a state involved in brain development, in a wild population of barn owls (Tyto alba) exhibiting inter-individual variation in melanism and covarying traits. In addition to sleep, we measured melanistic feather spots and the expression in the feather follicles of a gene implicated in melanism (PCSK2).
As in mammals, REM sleep declined with age across a period of brain development in owlets. In addition, inter-individual variation in REM sleep around this developmental trajectory was predicted by variation in PCSK2 expression in the feather follicles, with individuals expressing higher levels exhibiting a more precocial pattern characterized by less REM sleep. Finally, PCSK2 expression was positively correlated with feather spotting.
We demonstrate that the pace developmental processes occurring in the brain, as reflected in age-related changes in REM sleep, covary with the peripheral activation of the melanocortin system. Given its role in brain development, variation in nestling REM sleep may lead to variation in adult brain organization, and thereby contribute to the behavioral and physiological differences observed between adults expressing different degrees of melanism.

Richard B. Sherley, Peter J. Barham, Barbara J. Barham, Robert J. M. Crawford, Bruce M. Dyer, T. Mario Leshoro, Azwianewi B. Makhado, Leshia Upfold, Les G. Underhill
Growth and decline of a penguin colony and the influence on nesting density and reproductive success
Population Ecology August 2013

Colonial breeding is characteristic of seabirds but nesting at high density has both advantages and disadvantages and may reduce survival and fecundity. African penguins (Spheniscus demersus) initiated breeding at Robben Island, South Africa in 1983. The breeding population on the island increased in the late 1990s and early 2000s before decreasing rapidly until 2010. Before the number breeding peaked, local nest density in the areas where the colony was initiated plateaued, suggesting that preferred nests sites were mostly occupied, and the area used by breeding birds expanded. However, it did not contract again as the population decreased, so that nesting density varied substantially. Breeding success was related positively to the prey available to the breeding birds and negatively to local nest density, particularly during the chick-rearing period, suggesting a density-dependence operating through social interactions in the colony, possibly exacerbated by poor prey availability when the breeding population was large. Although nest density at Robben Island was not high, nesting burrows, which probably reduce the incidence of aggressive encounters in the colony, are scarce and our results suggest that habitat alteration has modified the strength of density-dependent relationships for African penguins. Gaining a better understanding of how density dependence affects fecundity and population growth rates in colonial breeders is important for informing conservation management of the African penguin and other threatened taxa.

Sandy M. Kawano, William C. Bridges, Heiko L. Schoenfuss, Takashi Maie, Richard W. Blob
Differences in locomotor behavior correspond to different patterns of morphological selection in two species of waterfall-climbing gobiid fishes
Evolutionary Ecology September 2013, Volume 27, Issue 5, pp 949-969

Behavior plays an important role in mediating relationships between morphology and performance in animals and, thus, can influence how selection operates. However, to what extent can the use of specific behaviors be associated with particular types of selection on morphological traits? Laboratory selection analyses on waterfall-climbing gobiid fishes were performed to investigate how behavioral variations in locomotion can affect patterns of linear and nonlinear morphological selection. Species from sister genera (Sicyopterus stimpsoni and Sicydium punctatum) that use different climbing behaviors were exposed to similar artificial waterfalls to simulate a controlled selective regime involving the climbing of a nearly vertical slope against flowing water. Juvenile S. stimpsoni “inch up” waterfalls by alternate attachment of oral and pelvic suckers with little axial or fin movement, leading to straightforward expectations that climbing selection should favor morphologies that improve drag reduction and substrate adhesion. In contrast, juvenile S. punctatum climb using substantial axial and fin movements, complicating expectations for selection patterns and potentially promoting correlational selection. Comparisons of directional, quadratic and correlational selection coefficients for various morphological traits and trait interactions indicated that these species showed different selection patterns that generally fit these predictions. Both directional and correlational selection patterns were different between the species, and on average were stronger in S. punctatum compared to S. stimpsoni. Stronger selection in S. punctatum may be related to its climbing style that requires more integrated movement of the fins and body axis than S. stimpsoni, promoting dynamic interactions among body regions within a complicated hydrodynamic environment.

Ahimsa Campos-Arceiz, Lian Pin Koh, Richard B. Primack, Are conservation biologists working too hard?, Biological Conservation, Volume 166, October 2013, Pages 186-190, ISSN 0006-3207, http://dx.doi.org/10.1016/j.biocon.2013.06.029.
The quintessential scientist is exceedingly hardworking and antisocial, and one who would spend countless evenings and weekends buried under her/his microscopes and manuscripts. In an attempt to bust this popular myth, we analyzed the work habits of conservation biologists using data from Biological Conservation’s online manuscript submission system, which includes more than 10,000 manuscript submissions and almost 15,000 reviews from between 2004 and 2012. We found that 11% of new manuscripts and 12% of manuscript reviews were submitted on weekends. Weekend submission rates increased by 5% and 6% for new manuscripts and reviews respectively per year during the study period. Chinese and Indian biologists worked the most on weekends compared to their colleagues elsewhere, submitting 19% of their manuscripts on Saturdays and Sundays. At the other end of the spectrum, Belgians and Norwegians submitted only 4% of manuscripts on weekends. Czech and Polish biologists were the most assiduous weekend reviewers, submitting 27% and 25% of reviews on weekends, respectively. Irish and Belgian reviewers worked the least on weekends, submitting only 6% of reviews during that time. Sixteen percent of new manuscripts were submitted on weekdays after regular office hours – between 19:00 pm and 07:00 am – with the highest rate of nighttime submissions by Japanese (30%), Mexican (26%) and Brazilian (22%) scientists. Finnish, South African and Swiss researchers, however, submitted only 9%, 10%, and 10% of new manuscripts after regular working hours. In general, our results suggest that conservation biologists work extensively on weekends and at night, that the trend for working on weekends is increasing over time, and that these patterns have strong geographical structure. These habits could have negative impacts on the quality of the work as well as on the life-work balance of conservation scientists. Universities and other scientific organizations should allocate more time during regular work hours for scientists to complete their research duties, including the submission and review of manuscripts.

Michal Ferenc, Ondřej Sedláček, Roman Fuchs
How to improve urban greenspace for woodland birds: site and local-scale determinants of bird species richness
Urban Ecosystems August 2013

Wooded habitats represent hotspots of urban biodiversity, however, urban development imposes pressure on biota in these refuges. Identification of the most influential habitat attributes and the role of local urban characteristics is crucial for proper decisions on management practices supporting biodiversity. We aimed to identify well manageable fine-scale habitat attributes to suggest specific, feasible and affordable management recommendations for green space in cities. We analysed species richness of woodland-associated bird communities and incidence of individual species at 290 sites in a wide variety of green areas scattered across the city of Prague, Czech Republic. Generalized linear mixed models (GLMM) and regression tree analyses were used to identify site-scale (100 m radius sampling sites) and local-scale (200 m and 500 m radius plots) habitat attributes shaping the bird communities at individual sites. Logistic regression was used to assess the responses of individual species to habitat characteristics. Our results imply that at the site scale, management practices should focus on maintenance and promoting species-diverse and older tree stands, with a mixture of coniferous and deciduous trees. Water-bodies and accompanying riparian habitats should be maintained and carefully managed to preserve high-quality remnants of natural vegetation. Presence of a few old trees (about 12 % of tree cover with DBH > 50 cm) or small urban standing water and watercourses enrich the bird community by at least two species. Species richness of woodland avifauna at particular sites is further supported by the total amount of tree cover in the surroundings, including scattered greenery of public spaces and private gardens. We conclude that proper management at site scale has the potential to increase biodiversity of the urban environment.

Zimkus, B. M. & Gvoždík, V. (2013). Sky Islands of the Cameroon Volcanic Line: a diversification hot spot for puddle frogs (Phrynobatrachidae: Phrynobatrachus). —Zoologica Scripta, 00, 000–000.
The continental highlands of the Cameroon Volcanic Line (CVL) represent biological ‘sky islands’ with high levels of species richness and endemism, providing the ideal opportunity to understand how orogenesis and historical climate change influenced species diversity and distribution in these isolated African highlands. Relationships of puddle frogs (Phrynobatrachus) endemic to the CVL are reconstructed to examine the patterns and timing of puddle frog diversification. Historical distributions were reconstructed using both elevation and geography data. Puddle frogs diversified in the CVL via several dispersal and vicariance events, with most of the locally endemic species distributed across the northern part of the montane forest area in the Bamenda-Banso Highlands (Bamboutos Mts., Mt. Lefo, Mt. Mbam, Mt. Oku and medium elevation areas connecting these mountains). Two new species, P. jimzimkusi sp. n. and P. njiomock sp. n., are also described based on molecular analyses and morphological examination. We find that these new species are most closely related to one another and P. steindachneri with the ranges of all three species overlapping at Mt. Oku. Phrynobatrachus jimzimkusi sp. n. is distributed in the southern portion of the continental CVL, P. njiomock sp. n. is endemic to Mt. Oku, and P. steindachneri is present in the northeastern part of the montane forest area. Both new species can be distinguished from all other puddle frogs by a combination of morphological characters, including their large size, ventral coloration and secondary sexual characteristics present in males. These results highlight the Bamenda-Banso Highlands, and specifically emphasize Mt. Oku, as a centre of diversification for puddle frogs, supporting the conservation importance of this region. Our results also provide new insights into the evolutionary processes shaping the CVL ‘sky islands’, demonstrating that lineage diversification in these montane amphibians is significantly older than expected with most species diverging from their closest relative in the Miocene. Whereas climatic changes during the Pliocene and Pleistocene shaped intraspecific diversification, most speciation events were significantly older and cannot be linked to Africa’s aridification in response to Pleistocene climate fluctuations.

Amélie Y. Davis, Nur Malas, Emily S. Minor
Substitutable habitats? The biophysical and anthropogenic drivers of an exotic bird’s distribution
Biological Invasions August 2013

The spread and distribution of exotic species depends on a number of factors, both anthropogenic and biophysical. The importance of each factor may vary geographically, making it difficult to predict where a species will spread. In this paper, we examine the factors that influence the distribution of monk parakeets (Myiopsitta monachus), a parrot native to South America that has become established in the United States. We use monk parakeet observations gathered from citizen-science datasets to inform a series of random forest models that examine the relative importance of biophysical and anthropogenic variables in different regions of the United States. We find that while the distribution of monk parakeets in the southern US is best explained by biophysical variables such as January dew point temperature and forest cover, the distribution of monk parakeets in the northern US appears to be limited to urban environments. Our results suggest that monk parakeets are unlikely to spread outside of urban environments in the northern United States, as they are not adapted to the climatic conditions in that region. We extend the notion of “substitutable habitats,” previously applied to different habitats in the same landscape, to exotic species in novel landscapes (e.g., cities). These novel landscapes provide resources and environmental conditions that, although very different from the species’ native habitat, still enable them to become established. Our results highlight the importance of understanding the regionally-specific factors that allow an exotic species to become established, which is key to predicting their expansion beyond areas of introduction.

Kazuya Nishida, Mitsuru Ohira, Yutaro Senga
Movement and assemblage of fish in an artificial wetland and canal in a paddy fields area, in eastern Japan
Landscape and Ecological Engineering August 2013

This study, carried out in a paddy fields area in eastern Japan, investigated the timing and patterns of fish movement and assemblage in an artificial wetland and canal. The number of Misgurnus anguillicaudatus and Lefua echigonia immigrating and emigrating between the wetland and the canal accounted for 80–90 % of all the sampled fish. M. anguillicaudatus, L. echigonia, Pseudorasbora parva and Rhynchocypris lagowskii were dominant in the wetland. Immigration of mature M. anguillicaudatus and L. echigonia was detected between late winter and spring. The standard length of the two loach species in the wetland was smaller than that in the canal. These results confirm that wetlands play a role in spawning and nursery for the two species of loaches. The standard length of P. parva in the wetland was smaller than in the canal. This suggests that the wetland was a more suitable spawning and nursery area for this fish species than the canal. L. echigonia used the wetland as a spawning and nursery area, but previous studies reported that the loach did not use paddy fields near the wetland. This could be because the paddy fields were irrigated between June and September and this period did not largely overlap with the fish spawning season. Therefore, we conclude that the conservation and restoration of wetlands, where water is present throughout the year, will contribute toward the preservation of the fish population in a paddy fields area.

Gridley, T., Cockcroft, V. G., Hawkins, E. R., Blewitt, M. L., Morisaka, T. and Janik, V. M. (2013), Signature whistles in free-ranging populations of Indo-Pacific bottlenose dolphins, Tursiops aduncus. Marine Mammal Science. doi: 10.1111/mms.12054
Common bottlenose dolphins (Tursiops truncatus) use individually distinctive signature whistles which are highly stereotyped and function as contact calls. Here we investigate whether Indo-Pacific bottlenose dolphins (T. aduncus) use signature whistles. The frequency trace of whistle contours recorded from three genetically distinct free-ranging populations was extracted and sorted into whistle types of similar shape using automated categorization. A signature whistle identification method based on the temporal patterns in signature whistle sequences of T. truncatus was used to identify signature whistle types (SWTs). We then compared the degree of variability in SWTs for several whistle parameters to determine which parameters are likely to encode identity information. Additional recordings from two temporarily isolated T. aduncus made during natural entrapment events in 2008 and 2009 were analyzed for the occurrence of SWTs. All populations were found to produce SWTs; 34 SWTs were identified from recordings of free-ranging T. aduncus and one SWT was prevalent in each recording of the two temporarily isolated individuals. Of the parameters considered, mean frequency and maximum frequency were the least variable and therefore most likely to reflect identity information encoded in frequency modulation patterns. Our results suggest that signature whistles are commonly used by T. aduncus.

Fisher-Reid, M. C., Engstrom, T. N., Kuczynski, C. A., Stephens, P. R. and Wiens, J. J. (2013), Parapatric divergence of sympatric morphs in a salamander: incipient speciation on Long Island?. Molecular Ecology. doi: 10.1111/mec.12412
Speciation is often categorized based on geographic modes (allopatric, parapatric or sympatric). Although it is widely accepted that species can arise in allopatry and then later become sympatrically or parapatrically distributed, patterns in the opposite direction are also theoretically possible (e.g. sympatric lineages or ecotypes becoming parapatric), but such patterns have not been shown at a macrogeographic scale. Here, we analyse genetic, climatic, ecological and morphological data and show that two typically sympatric colour morphs of the salamander Plethodon cinereus (redback and leadback) appear to have become parapatrically distributed on Long Island, New York, with pure-redback populations in the west and pure-leadback populations in the east (and polymorphic populations in between and on the mainland). In addition, the pure-leadback populations in eastern Long Island are genetically, ecologically and morphologically divergent from both mainland and other Long Island populations, suggesting the possibility of incipient speciation. This parapatric separation seems to be related to the different ecological preferences of the two morphs, preferences which are present on the mainland and across Long Island. These results potentially support the idea that spatial segregation of sympatric ecotypes may sometimes play an important part in parapatric speciation.

Vandercone, R., Premachandra, K., Wijethunga, G. P., Dinadh, C., Ranawana, K. and Bahar, S. (2013), Random walk analysis of ranging patterns of sympatric langurs in a complex resource landscape. Am. J. Primatol.. doi: 10.1002/ajp.22183
The identification of random walk models to characterize the movement patterns of social groups of primates, and the behavioral processes that give rise to such movement patterns, remain open questions in movement ecology. Movement patterns characterized by a power-law tail with exponent between 1 and 3 (Lévy flight) occur when animals forage on scarce, randomly distributed resources. For primates and similar foragers with memory processes, movements resembling Lévy flights emerge when feeding trees (targets) are randomly distributed and the trunk size distribution of targets follows a power-law. We tested three competing random walk models to describe movement patterns of two langur species. We found a truncated power law to be the most suitable model. The power-law model was poorly supported by the data and hence we found no support for Lévy-flight-like behavior. Moreover, the spatial distribution of feeding trees and the probability distribution of feeding tree size differed from values suggested to result in Lévy-flight-like patterns. We identify intraspecific territoriality, foraging behavior, and the spatial and size distribution of food patches as plausible mechanisms that may have given rise to the observed movement patterns.

Hagen, C. A., Grisham, B. A., Boal, C. W. and Haukos, D. A. (2013), A meta-analysis of lesser prairie-chicken nesting and brood-rearing habitats: Implications for habitat management. Wildlife Society Bulletin. doi: 10.1002/wsb.313
The distribution and range of lesser prairie-chicken (Tympanuchus pallidicinctus) has been reduced by >90% since European settlement of the Great Plains of North America. Currently, lesser prairie-chickens occupy 3 general vegetation communities: sand sagebrush (Artemisia filifolia), sand shinnery oak (Quercus havardii), and mixed-grass prairies juxtaposed with Conservation Reserve Program grasslands. As a candidate for protection under the Endangered Species Act, there is a need for a synthesis that characterizes habitat structure rangewide. Thus, we conducted a meta-analysis of vegetation characteristics at nest sites and brood habitats to determine whether there was an overall effect (Hedges‘ d) of habitat selection and to estimate average (95% CI) habitat characteristics at use sites. We estimated effect sizes (di) from the difference between use (nests and brood sites) and random sampling sites for each study (n = 14), and derived an overall effect size (d++). There was a general effect for habitat selection as evidenced by low levels of variation in effect sizes across studies and regions. There was a small to medium effect (d++ = 0.20–0.82) of selection for greater vertical structure (visual obstruction) by nesting females in both vegetation communities, and selection against bare ground (d++ = 0.20–0.58). Females with broods exhibited less selectivity for habitat components except for vertical structure. The variation of d++ was greater during nesting than brooding periods, signifying a seasonal shift in habitat use, and perhaps a greater range of tolerance for brood-rearing habitat. The overall estimates of vegetation cover were consistent with those provided in management guidelines for the species

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