02218nas a2200181 4500008004100000022001400041245011600055210006900171260001600240520157000256100001601826700002301842700001701865700002201882700002201904700002101926856008901947 2021 eng d a0004-803800aComparative phylogeographic analysis suggests a shared history among eastern North American boreal forest birds0 aComparative phylogeographic analysis suggests a shared history a cApr-15-20223 a

Phylogeographic structure within high-latitude North American birds is likely shaped by a history of isolation in refugia during Pleistocene glaciations. Previous studies of individual species have come to diverse conclusions regarding the number and location of likely refugia, but no studies have explicitly tested for biogeographic concordance in a comparative phylogeographic framework. Here we use a hierarchical approximate Bayesian computation analysis of mitochondrial DNA sequences from 653 individuals of 6 bird species that are currently co-distributed in the boreal forest of North America to test for biogeographic congruence. We find support for congruent phylogeographic patterns across species, with shallow divergence dating to the Holocene within each species. Combining genetic results with paleodistribution modeling, we propose that these species shared a single Pleistocene refugium south of the ice sheets in eastern North America. Additionally, we assess modern geographic genetic structure within species, focusing on Newfoundland and disjunct high-elevation populations at the southern periphery of ranges. We find evidence for a “periphery effect” in some species with significant genetic structure among peripheral populations and between peripheral and central populations. Our results suggest that reduced gene flow among peripheral populations, rather than discordant biogeographic histories, can explain the small differences in genetic structure and levels of genetic diversity among co-distributed boreal forest birds.

1 aRalston, J.1 aFitzGerald, A., M.1 aBurg, T., M.1 aStarkloff, N., C.1 aWarkentin, I., G.1 aKirchman, J., J. uhttps://academic.oup.com/auk/advance-article/doi/10.1093/ornithology/ukab018/622620902122nas a2200217 4500008004100000245012300041210006900164300001000233490000800243520128000251653002401531653002301555653001701578653002001595653002801615100001601643700002701659700001901686700002101705856017801726 2019 eng d00aObservations of habitat associations in boreal forest birds and the geographic variation in bird community composition0 aObservations of habitat associations in boreal forest birds and  a12-230 v1313 a

Differences in habitat associations or responses to environmental stressors among broadly co-distributed species can result in local variation in community composition. As a result, ongoing environmental change may drive shifts in community composition, especially at range peripheries. In the present study, we describe regional variation in avian community composition at the southern extent of the boreal zone. Boreal bird communities are disproportionally influenced by ongoing climate change and contain several declining species. Here we observe the habitat associations for 13 boreal bird species, and assess the link between species' habitat associations and community composition. We conducted standardized point counts at 20 boreal forest sites in northeastern United States and Canada, and quantified the vegetation structure and composition as well as the climate at each site. We found large variation in the habitat associations among co-distributed boreal birds, both in terms of the specific variables important for each species and in the breadth of habitat types occupied. These findings suggest that species within this community will vary in their responses to environmental change, potentially resulting in changes to the boreal avian community.

10acommunity structure10ahabitat ordination10arange limits10arange periphery10aspruce-fir forest birds1 aRalston, J.1 aFitzGerald, Alyssa, M.1 aScanga, S., E.1 aKirchman, J., J. uhttps://bioone.org/journals/the-wilson-journal-of-ornithology/volume-131/issue-1/18-14/Observations-of-habitat-associations-in-boreal-forest-birds-and-the/10.1676/18-14.full02262nas a2200205 4500008004100000245010800041210006900149300001000218490000800228520164800236653001601884653001801900653001601918653001401934653001201948100001601960700002001976700002101996856003902017 2015 eng d00aA New Wood Warbler Hybrid (Oreothlypis celata x O. ruficapilla) from the Adirondack Mountains, New York0 aNew Wood Warbler Hybrid Oreothlypis celata x O ruficapilla from  a21-280 v1273 a

The incidence rate of hybridization appears to be much higher for parulid warblers compared to other bird taxa. Over 50% of the species in this family have been reported to hybridize. Here, we report genetic and morphometric analysis of a suspected hybrid of a previously unreported species cross in the genus Oreothlypis, captured in a montane spruce-fir forest in the Adirondack Mountains of New York. We compared sequences of the mitochondrial ND2 and the nuclear Z chromosomal aconitase intron 9 to published warbler sequences to determine parentage, and compared plumage and morphology to museum specimens. ND2 sequence closely matched Orange-crowned Warbler (O. celata), while aconitase matched Nashville Warbler (O. ruficapilla). Because our specimen was a male and was homozygous for ruficapilla alleles at the Z chromosome, we determined the hybridization event occurred at least two generations ago. This suggests hybridization between these species produces viable offspring. Plumage of the warbler was nearly indistinguishable from pure Nashville Warbler specimens. A Principle Components Analysis of morphometric data showed the hybrid to be morphologically intermediate between the two parent species. This hybridization event occurred well outside of Orange-crowned Warblers' breeding distribution, a finding consistent with Hubbs' principle which states that hybridization is more likely when conspecifics are rare or unavailable. Our finding demonstrates the importance of specimen collecting and genetic methods in documenting aspects of natural history that may be cryptic or infrequent in nature.

10aAdirondacks10ahybridization10aOreothlypis10aParulidae10awarbler1 aRalston, J.1 aErmacor, D., A.1 aKirchman, J., J. uhttp://dx.doi.org/10.1676/14-052.100712nas a2200193 4500008004100000245016100041210006900202300001200271490000700283653002400290653001900314653002600333653002000359653002200379653003200401100001600433700002100449856004800470 2013 eng d00aPredicted Range Shifts in North American Boreal Forest Birds and the Effect of Climate Change on Genetic Diversity in Blackpoll Warblers (Setophaga striata)0 aPredicted Range Shifts in North American Boreal Forest Birds and a543-5550 v1410aBoreal forest birds10aclimate change10aConservation genetics10aMicrosatellites10aSetophaga striata10aSpecies distribution models1 aRalston, J.1 aKirchman, J., J. uhttp://dx.doi.org/10.1007/s10592-012-0418-y02220nas a2200241 4500008004100000245010800041210006900149300001200218490000800230520144100238653002201679653001801701653002401719653002001743653002201763653002401785653002401809653002201833653003101855100001601886700002101902856005501923 2012 eng d00aContinent-scale Genetic Structure in a Boreal Forest Migrant, the Blackpoll Warbler (Setophaga striata)0 aContinentscale Genetic Structure in a Boreal Forest Migrant the  a467-4780 v1293 a
Abstract We describe the range-wide phylogeography of Blackpoll Warblers (Setophaga striata), a migratory passerine with a broad breeding range in North America's boreal forest that encompasses several possible biogeographic barriers but shows no phenotypic geographic variation. We used mitochondrial control-region sequences from 304 individuals in combination with ecological niche models and coalescent simulations to test alternative historical hypotheses about the number of Pleistocene refugial populations and divergences among modern populations. Population pairwise FST and spatial analyses of molecular variance suggested significant genetic structure among western, eastern, and Newfoundland populations, but no structure among sky-island populations at the southeastern periphery of the breeding range. Inferred gene flow fits a model of isolation-by-distance. Coalescent simulations rejected all multiple-refugia hypotheses in favor of a single refugium. Paleodistribution models and modern migratory pathways suggested that the refugium was located in southeastern North America. In contrast to previous studies that have invoked multiple Pleistocene refugia as the cause of genetic structure in North American bird species, our analyses suggest that geographic structure in Blackpoll Warblers results from isolation-by-distance rather than a history of sundered populations.
10aBlackpoll Warbler10aboreal forest10acoalescent analysis10amigratory birds10amitochondrial DNA10aPleistocene refugia10apopulation genetics10aSetophaga striata10astatistical phylogeography1 aRalston, J.1 aKirchman, J., J. uhttp://www.jstor.org/stable/10.1525/auk.2012.11260