Central‐West Siberian‐breeding Bar‐tailed Godwits (Limosa lapponica) segregate in two morphologically distinct flyway populations

Abstract

Long-distance migratory species often include multiple breeding populations, with distinct migration routes, wintering areas and annual-cycle timing. Detailed knowledge on population structure and migratory connectivity provides the basis for studies on the evolution of migration strategies and for species conservation. Currently, five subspecies of Bar-tailed Godwits Limosa lapponica have been described. However, with two apparently separate breeding and wintering areas, the taxonomic status of the subspecies L. l. taymyrensis remains unclear. Here we compare taymyrensis Bar-tailed Godwits wintering in the Middle East and West Africa, respectively, with respect to migration behaviour, breeding area, morphology and population genetic differentation in mitochondrial DNA. By tracking 52 individuals from wintering and staging areas over multiple years, we show that Bar-tailed Godwits wintering in the Middle East bred on the northern West-Siberian Plain (n = 19), while birds from West Africa bred further east, mostly on the Taimyr Peninsula (n = 12). The two groups differed significantly in body size and shape, and also in the timing of both northward and southward migrations. However, they were not genetically differentiated, indicating that the phenotypic (i.e. geographical, morphological and phenological) differences arose either very recently or without current reproductive isolation. We conclude that the taymyrensis taxon consists of two distinct

Global temperature homogenization can obliterate temporal isolation in migratory animals with potential loss of population structure

“…José A. Alves: Conceptualization; funding acquisition; resources; writing -review and editing. Eldar Rakhimberdiev: Conceptualization; formal analysis; writing -original draft.ACK N O WLE D G E M ENTSThis analytic paper builds on the descriptive work and considerable field efforts by an international team acknowledged inBom et al (2022). We thank all people that helped with catching and tag-ging bar-tailed godwits, in particular Kees Oosterbeek, Job ten Horn, Anne Dekinga, Ana Coelho, and Afonso Rocha.…”

“…They are indistinguishable in neutral genetic markers, but their morphologically distinctiveness suggests that there is little or no gene flow (i.e., exchange of individuals) between populations (Bom et al., 2022). The two subspecies have different wintering areas, in the Middle East and West Africa, respectively, but they have two shared stopover areas, being therefore partially sympatric (Bom et al., 2022). One, the ‘spring overlap area’ is at—and south of—the Yamal Peninsula (Figure 1).…”

“…Homogenization of previously isolated populations could be an important consequence of increasing synchronized environments and hence climate change. difference in timing is probably related to the date of snowmelt in each population breeding area (i.e., later at Taimyr than at Yamal) and is thought to facilitate reproductive isolation (Bom et al, 2022).…”

“…We examine the potential (consequences of) temporal synchronization in the onset of spring in two subspecies of bar‐tailed godwits Limosa lapponica yamalensis and Limosa lapponica taymyrensis (Bom et al., 2022). The two subspecies breed in adjacent tundra regions in Russia, respectively in Yamal ( yamalensis ) in the west and Taimyr further east and north ( taymyrensis ).…”

The need to account for Argos Doppler errors when estimating habitat use from Argos Doppler locations: evidence and solution

“…Despite their low precision, raw Argos locations have long been used as an approximation of true locations [3]. This practice can be acceptable for the analysis of larger scale movements, such as the seasonal movements of migratory animals [8][9][10][11]. However, when the scale of inference starts to fall within the range of the location uncertainty, using raw Argos locations is no longer appropriate.…”