Western Veeries use an eastern shortest-distance pathway: New insights to migration routes and phenology using light-level geolocators

Hobson, Keith A.; Kardynal, Kevin J.

doi:10.1642/auk-14-260.1

Cited by 36 publications

(58 citation statements)

References 50 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For example, Veeries ( Catharus fuscescens ) and Swainson's Thrushes ( Catharus ustulatus ) breeding in the Okanagan Valley of western Canada traverse the Rocky Mountains eastward during fall migration and then cross the Great Plains, Gulf of Mexico or Caribbean Sea (Delmore et al. , Delmore and Irwin , Hobson and Kardynal ). That route joins the presumably ancestral fall movement of eastern populations of Veeries and also more closely tracks a shorter orthodromic (Great Circle) than a loxodromic (rhumb line) route (Hobson and Kardynal ).…”

mentioning

confidence: 99%

The pull of the Central Flyway? Veeries breeding in western Canada migrate using an ancestral eastern route

Kardynal

Hobson

2017

J. Field Ornithol.

Self Cite

View full text Add to dashboard Cite

Understanding non‐breeding season movements and identifying wintering areas of different populations of migratory birds is important for establishing patterns of migratory connectivity over the annual cycle. We analyzed archival solar geolocation (N = 5) and global positioning data (N = 1) to investigate migration routes, stopover sites, and wintering areas of a western‐most breeding population of Veeries (Catharus fuscescens) in the Pemberton Valley, British Columbia, Canada. Geolocation data were analyzed using a Bayesian state‐space model to improve likely position estimates. We compared our results with those from a Veery population located ~250 km east across a mountain chain in the Okanagan Valley, British Columbia, and with an eastern population in Delaware, U.S.A. Migrating Veeries from the Pemberton Valley used an eastern trajectory through the Rocky Mountains to the Great Plains to join a central flyway during fall and spring migration, a route similar to that used by Veeries breeding in the Okanagan Valley. However, wintering destinations of Pemberton Valley birds were more varied, with inter‐individual wintering distances ~1000 km greater than birds from the Okanagan Valley population and ~500 km from the previously known winter range of Veeries. The observed eastern migration path likely follows an ancestral route that evolved following the most recent glacial retreat. Consistent with patterns observed from the Okanagan and Delaware populations, Veeries from the Pemberton Valley undertook an intra‐tropical migration on the wintering grounds, but this winter movement differed from those of previously studied populations. Such winter movements may thus be idiosyncratic or show coarse population associations. Intra‐wintering‐ground movements likely occur either in response to seasonal changes in habitat suitability or as a means of optimizing pre‐migratory fueling prior to long‐distance spring movements to North America.

show abstract

mentioning

confidence: 99%

The pull of the Central Flyway? Veeries breeding in western Canada migrate using an ancestral eastern route

Kardynal

Hobson

2017

J. Field Ornithol.

Self Cite

View full text Add to dashboard Cite

show abstract

“…within year dispersal movements prior to fall migration) and molt occurring elsewhere in the species breeding range (e.g. [59]).…”

Section: Discussionmentioning

confidence: 99%

“…Results from Vander Zanden et al [52] also suggest that the need to use year-specific δ 2 H f isoscapes would depend on the study region because the degree of inter-annual variation in δ 2 H p differs among regions. It is also likely that we are close to identifying the limit of accuracy of this single isotope approach, highlighting the importance of combining multiple markers in multivariate assignment tests [59, 61–63]. …”

Section: Discussionmentioning

confidence: 99%

Within-Site Variation in Feather Stable Hydrogen Isotope (δ2Hf) Values of Boreal Songbirds: Implications for Assignment to Molt Origin

et al. 2016

Self Cite

View full text Add to dashboard Cite

Understanding bird migration and dispersal is important to inform full life-cycle conservation planning. Stable hydrogen isotope ratios from feathers (δ2Hf) can be linked to amount-weighted long-term, growing season precipitation δ2H (δ2Hp) surfaces to create δ2Hf isoscapes for assignment to molt origin. However, transfer functions linking δ2Hp with δ2Hf are influenced by physiological and environmental processes. A better understanding of the causes and consequences of variation in δ2Hf values among individuals and species will improve the predictive ability of geographic assignment tests. We tested for effects of species, land cover, forage substrate, nest substrate, diet composition, body mass, sex, and phylogenetic relatedness on δ2Hf from individuals at least two years old of 21 songbird species captured during the same breeding season at a site in northeastern Alberta, Canada. For four species, we also tested for a year × species interaction effect on δ2Hf. A model including species as single predictor received the most support (AIC weight = 0.74) in explaining variation in δ2Hf. A species-specific variance parameter was part of all best-ranked models, suggesting variation in δ2Hf was not consistent among species. The second best-ranked model included a forage substrate × diet interaction term (AIC weight = 0.16). There was a significant year × species interaction effect on δ2Hf suggesting that interspecific differences in δ2Hf can differ among years. Our results suggest that within- and among-year interspecific variation in δ2Hf is the most important source of variance typically not being explicitly quantified in geographic assignment tests using non-specific transfer functions to convert δ2Hp into δ2Hf. However, this source of variation is consistent with the range of variation from the transfer functions most commonly being propagated in assignment tests of geographic origins for passerines breeding in North America.

show abstract

“…However, inspection of our raw geolocation data indicated that it was likely some of the birds remained close to their nesting sites but were not roosting in the nesting structure prior to migration. Therefore, using the results from the state-space Kalman filter models, large (≥ 150 km) consistent (e.g., south) directional movements away from the breeding grounds for two or more days were used as determinants of departure from the breeding grounds including during the equinox when only longitude could be used [32]. Start and end dates of the wintering period were first estimated using the changeLight function in the R GeoLight package [24] which iteratively searches for breakpoints in the light data to determine potential residency and migration periods.…”

Section: Methodsmentioning

confidence: 99%

A Continent-Wide Migratory Divide in North American Breeding Barn Swallows (Hirundo rustica)

et al. 2015

Self Cite

View full text Add to dashboard Cite

Populations of most North American aerial insectivores have undergone steep population declines over the past 40 years but the relative importance of factors operating on breeding, wintering, or stopover sites remains unknown. We used archival light-level geolocators to track the phenology, movements and winter locations of barn swallows (Hirdundo rustica; n = 27) from populations across North America to determine their migratory connectivity. We identified an east-west continental migratory divide for barn swallows with birds from western regions (Washington State, USA (n = 8) and Saskatchewan, Canada (n = 5)) traveling shorter distances to wintering areas ranging from Oregon to northern Colombia than eastern populations (Ontario (n = 3) and New Brunswick (n = 10), Canada) which wintered in South America south of the Amazon basin. A single swallow from a stable population in Alabama shared a similar migration route to eastern barn swallows but wintered farther north in northeast Brazil indicating a potential leap frog pattern migratory among eastern birds. Six of 9 (67%) birds from the two eastern populations and Alabama underwent a loop migration west of fall migration routes including around the Gulf of Mexico travelling a mean of 2,224 km and 722 km longer on spring migration, respectively. Longer migration distances, including the requirement to cross the Caribbean Sea and Gulf of Mexico and subsequent shorter sedentary wintering periods, may exacerbate declines for populations breeding in northeastern North America.

show abstract

Western Veeries use an eastern shortest-distance pathway: New insights to migration routes and phenology using light-level geolocators

Cited by 36 publications

References 50 publications

The pull of the Central Flyway? Veeries breeding in western Canada migrate using an ancestral eastern route

The pull of the Central Flyway? Veeries breeding in western Canada migrate using an ancestral eastern route

Within-Site Variation in Feather Stable Hydrogen Isotope (δ2Hf) Values of Boreal Songbirds: Implications for Assignment to Molt Origin

A Continent-Wide Migratory Divide in North American Breeding Barn Swallows (Hirundo rustica)

Contact Info

Product

Resources

About