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Ecogeographic rules denote spatial patterns in phenotype and environment that may reflect local adaptation as well as a species' capacity to adapt to change. To identify genes underlying Bergmann's Rule, which posits that spatial correlations of body mass and temperature reflect natural selection and local adaptation in endotherms, we compare 79 genomes from nine song sparrow (Melospiza melodia) subspecies that vary ~300% in body mass (17 − 50 g). Comparing large- and smaller-bodied subspecies revealed 9 candidate genes in three genomic regions associated with body mass. Further comparisons to the five smallest subspecies endemic to California revealed eight SNPs within four of the candidate genes (GARNL3, RALGPS1, ANGPTL2, and COL15A1) associated with body mass and varying as predicted by Bergmann's Rule. Our results support the hypothesis that co-variation in environment, body mass and genotype reflect the influence of natural selection on local adaptation and a capacity for contemporary evolution in this diverse species. Ecogeographic rules link spatial patterns in phenotype and environment, potentially reflecting adaptation. This study identifies nine genes associated with body mass variation in song sparrow populations, supporting Bergmann's Rule and highlighting the role of natural selection in local adaptation. [ABSTRACT FROM AUTHOR]

Anthropogenic noise and its effects on acoustic communication have received considerable attention in recent decades. Yet, the natural acoustic environment's influence on communication and its role in shaping acoustic signals remains unclear. We used large-scale playbacks of ocean surf in coastal areas and whitewater river noise in riparian areas to investigate how natural sounds influences song structure in six songbird species. We recorded individuals defending territories in a variety of acoustic conditions across 19 study sites in California and 18 sites in Idaho. Acoustic characteristics across the sites included naturally quiet 'control' sites, 'positive control' sites that were adjacent to the ocean or a whitewater river and thus were naturally noisy, 'phantom' playback sites that were exposed to continuous broadcast of low-frequency ocean surf or whitewater noise, and 'shifted' playback sites with continuous broadcast of ocean surf or whitewater noise shifted up in frequency. We predicted that spectral and temporal song structure would generally correlate with background sound amplitude and that signal features would differ across site types based on the spectral profile of the acoustic environment. We found that the ways in which song structure varied with background acoustics were quite variable from species to species. For instance, in Idaho both the frequency bandwidth and duration of lazuli bunting (Passerina amoena) and song sparrow (Melospiza melodia) songs decreased with elevated background noise, but these song features were unrelated to background noise in the warbling vireo (Vireo gilvus), which tended to increase both the minimum and maximum frequency of songs with background noise amplitude. In California, the bandwidth of the trill of white-crowned sparrow (Zonotrichia leucophrys) song decreased with background noise amplitude, matching results of previous studies involving both natural and anthropogenic noise. In contrast, wrentit (Chamaea fasciata) song bandwidth was positively related to the amplitude of background noise. Although responses were quite heterogeneous, song features of all six species varied with amplitude and/or frequency of background noise. Collectively, these results provide strong evidence that natural soundscapes have long influenced vocal behavior. More broadly, the evolved behavioral responses to the long-standing challenges presented by natural sources of noise likely explain the many responses observed for species communicating in difficult signal conditions presented by human-made noise. [ABSTRACT FROM AUTHOR]

Disentangling the effects of neutral and adaptive processes in maintaining phenotypic variation across environmental gradients is challenging in natural populations. Song sparrows (Melospiza melodia) on the California Channel Islands occupy a pronounced east‐west climate gradient within a small spatial scale, providing a unique opportunity to examine the interaction of genetic isolation (reduced gene flow) and the environment (selection) in driving variation. We used reduced representation genomic libraries to infer the role of neutral processes (drift and restricted gene flow) and divergent selection in driving variation in thermoregulatory traits with an emphasis on the mechanisms that maintain bill divergence among islands. Analyses of 22,029 neutral SNPs confirm distinct population structure by island with restricted gene flow and relatively large effective population sizes, suggesting bill differences are probably not a product of genetic drift. Instead, we found strong support for local adaptation using 3294 SNPs in differentiation‐based and environmental association analyses coupled with genome‐wide association tests. Specifically, we identified several putatively adaptive and candidate loci in or near genes involved in bill development pathways (e.g., BMP, CaM, Wnt), confirming the highly complex and polygenic architecture underlying bill morphology. Furthermore, we found divergence in genes associated with other thermoregulatory traits (i.e., feather structure, plumage colour, and physiology). Collectively, these results suggest strong divergent selection across an island archipelago results in genomic changes in a suite of traits associated with climate adaptation over small spatial scales. Future research should move beyond studying univariate traits to better understand multidimensional responses to complex environmental conditions. [ABSTRACT FROM AUTHOR]

Water crises and endangered salmon are pressing environmental concerns influencing restoration decisions in the western United States. When instream restoration necessitates initial loss of riparian cover to restore floodplain function, a short-term goal to minimize harm to riparian-associated wildlife is a worthwhile benchmark. From 2012 to 2015, we examined short-term restoration success, as measured by territory characteristics and reproductive success in restored and reference sites, for 3 riparian bird species (Song Sparrow [Melospiza melodia], Yellow-breasted Chat [Icteria virens], and Yellow Warbler [Setophaga petechia]) along a 64 km stretch of the Trinity River, California. Territory size had the highest relative variable importance in sets of candidate models explaining territory density for all 3 species, and was inversely related to territory density for each. The effect of site type (i.e. restored vs. reference) in explaining territory density was least for Song Sparrow, greater for Yellow Warbler (for which density was 1.4 times greater on reference sites), and greatest for Yellow-breasted Chat (which were more than twice as dense on reference sites). While territory density and mean territory size were inversely related, we found no relationship between territory density or site type and mean productivity per nest, and nest success did not differ between restored and reference sites for any species. In combination, these results suggest that restoration has achieved short-term success as measured by reproductive success, but has not yet been fully successful in supporting similar territory densities as reference sites. In order to determine whether long-term restoration goals are fully achieved, future research should continue to measure density of the 3 focal species as vegetation on the replanted floodplains matures. [ABSTRACT FROM AUTHOR]

The issue of band wear and band loss has been a concern of bird banders for many years, but has primarily been a concern to larger, longer lived marine birds. There are few reports of and less concern for band wear in smaller, terrestrial, primarily passerine birds. Forty-four worn bands from ten passerine species, California {formerly Western} Scrub-Jay [Aphelocoma califomica], Bewick's Wren [Thryomanes bewickii], Wrentit [Chamaea fasciata], California Thrasher [Toxostoma redivivum], California Towhee [Melozone ={Pipilo} crissalis], Spotted Towhee [Pipilo maculatus], Fox Sparrow [Passerella iliaca], Song Sparrow [Melospiza meloidia], Gambel's Whitecrowned Sparrow [Zonotrichia leucophrys gambelii], and Purple Finch [Haemorhous purpureus], are reported here, coming from six of the smaller hand sizes (l, IB, I A, ID, 2, and 3). The percent weight loss per year are comparable to larger, marine birds. Although the actual age at which bands would be lost is not available, the age of the band at which the bander felt that the band was worn su fficiently enough to need replacing averaged about three to four years. This was often less than half of the longevity records for most passerines. Thus, we should concern ourselves with life history studies relying on bird banding records. [ABSTRACT FROM AUTHOR]

The spatial genetic structure of populations is strongly influenced by current and historical patterns of gene flow and drift, which in the simplest case, is limited by geographic distance. We examined the microspatial genetic structure within 33 populations of song sparrows ( Melospiza melodia) which included eight subspecies located across coastal areas in southern British Columbia (BC) and California. We also examined the effect of water barriers and local density estimates on genetic structuring. Across both regions, positive genetic structure was detectable at distances of less than 10 km. Genetic divergence was highest in Californian subspecies, perhaps due to reduced gene flow across sub-specific contact zones. In BC, populations distributed across islands displayed greater genetic structuring over similar spatial scales than those across mainland sites, supporting the prediction that water barriers reduce gene flow in this species. Our results confirm both the expectation for fine-scale genetic structure in these generally sedentary subspecies, and the role of landscape features in generating geographic variation in genetic structure. [ABSTRACT FROM AUTHOR]

The article presents a study on the effect of mist netting on Wrentits and Song Sparrows' reproductive performance with the use of a 25-year data set in central California. The study compares nest survival of Song Sparrow which is high while the Wrentit has poor condition, but there was no statistical evidence that mist netting affects the reproductive performance of the species. It then concludes that the use of mist nests in studying avian demographics is safe.

Current geographic variation in bird song dialects may be used to infer historical processes involved in dialect formation. Discrete island populations, separated by water or unsuitable habitat, may be particularly useful as they allow for unequivocal subdivision of populations. Song recordings of nine populations of the white-crowned sparrow were analyzed within the San Francisco Bay area, both on 'true' islands separated by water and in habitat islands along the Bay shore. One or two unique songtypes in each population was found with little variation within songtypes among individuals. There were differences in songtypes concerning variation in syntax, syllable shapes, and spectral and temporal features. While each songtype exhibited unique features, there were often parts of the song that showed high similarity with songtypes of neighboring populations. Successfully dispersing males may learn from multiple tutors and produce songtype hybrids, which could explain the variation in songtypes among populations. Rare acoustic features were found on the 'true' islands, but also an apparent lack of impact by water barriers on the relationship between song similarity and geographic distance. A possible explanation may be that male dispersal, or just spread of song characteristics, is predominantly from island to mainland. Such a unidirectional pattern could result in rare song characteristics on islands, while general acoustic characteristics are still shared with the nearest mainland populations. Variation in similarity-based clustering of songtypes suggested that new songtypes emerge through recombination of components from existing songtypes. [ABSTRACT FROM AUTHOR]

Presents a study that examined the genetic population structure of putative subspecies of song sparrows in the San Francisco Bay region in California through microsatellite loci analysis to assist the development of song sparrow conservation and management strategies. Level of differentiation between populations within subspecies; Genetic structure at the subspecies level; Details of a proposed conservation of a management unit encompassing the range of song sparrows.

The article reports on the 2009 bird banding at the Klamath Bird Observatory (KBO) in the Klamath-Siskiyou Bioregion in California and Oregon. KBO banded a total of 11,018 birds of 101 species with a total of 14,510 net hours. The top ten banded birds include the dark-eyed junco, orange-crowned warbler and song sparrow. In addition to banding, KBO also conducted tissue sampling, nocturnal bioacoustical monitoring and banding-related outreach and education efforts.

Life history trade-offs have been posited to shape wild animals' immune responses against microparasites (e.g., bacteria, viruses). However, coinfection with gut helminths may bias immune phenotypes away from inflammatory responses and could be another mechanism underlying variation in immune responses. We examined how the magnitude of a common and costly response to microparasites, the acute phase response (APR), varied with helminth coinfection at both the individual and the population levels in Song Sparrows ( Melospiza melodia). The APR includes fever and sickness behaviors, like lethargy and anorexia, and provides a whole-organism metric of immune activation. We combined data on fever and lethargy in response to an immune challenge (lipopolysaccharide) with postmortem data assessing helminth burdens and data on malarial parasite infection from blood samples in sparrows from two populations: southern California and western Washington, US. We predicted that birds with higher helminth burdens would express less severe APRs, at both the individual and population levels. Furthermore, we predicted that these reduced immune responses would diminish resistance against malarial parasites and would thus be associated with higher prevalences of such parasites. Previously, Song Sparrows from Washington have been shown to mount less severe APRs than those from California. In our study, Washington birds also exhibited higher helminth burdens and a higher prevalence of one type of avian malarial parasite. Because of low variation in helminth burdens in California (median=0, range=0-3), we tested within-population relationships only in birds from Washington, where the severity of fever and lethargy correlated negatively with helminth burden. These results suggested that helminth coinfection could help mediate immune responsiveness in wild songbirds.