Population structure of Purple Sandpipers (Calidris maritima) as revealed by mitochondrial DNA and microsatellites

Abstract

The Purple Sandpiper (Calidris maritima) is a medium‐sized shorebird that breeds in the Arctic and winters along northern Atlantic coastlines. Migration routes and affiliations between breeding grounds and wintering grounds are incompletely understood. Some populations appear to be declining, and future management policies for this species will benefit from understanding their migration patterns. This study used two mitochondrial DNA markers and 10 microsatellite loci to analyze current population structure and historical demographic trends. Samples were obtained from breeding locations in Nunavut (Canada), Iceland, and Svalbard (Norway) and from wintering locations along the coast of Maine (USA), Nova Scotia, New Brunswick, and Newfoundland (Canada), and Scotland (UK). Mitochondrial haplotypes displayed low genetic diversity, and a shallow phylogeny indicating recent divergence. With the exception of the two Canadian breeding populations from Nunavut, there was significant genetic differentiation among samples from all breeding locations; however, none of the breeding populations was a monophyletic group. We also found differentiation between both Iceland and Svalbard breeding populations and North American wintering populations. This pattern of divergence is consistent with a previously proposed migratory pathway between Canadian breeding locations and wintering grounds in the United Kingdom, but argues against migration between breeding grounds in Iceland and Svalbard and wintering grounds in North America. Breeding birds from Svalbard also showed a genetic signature intermediate between Canadian breeders and Icelandic breeders. Our results extend current knowledge of Purple Sandpiper population genetic structure and present new information regarding migration routes to wintering grounds in North America.

Development of a sensitive and specific qPCR method to detect duck and goose DNA in meat and feathers

“…For feathers, the isolation efficiency depends on the tested fragment, and the isolation efficiency is ten times lower for down than for calamus. These results are in accordance with earlier observations [11]. The slightly decreased purity parameter (< 1.8) for feather samples is indicative of protein contamination, likely associated with keratin, which other authors have reported in feather extracts [12].…”

Pleistocene glacial cycles as drivers of allopatric differentiation in Arctic shorebirds

“…Recent works have focused mainly on the resulting spatial genetic patterns in different northern bird species (e.g. Jones et al., 2005; Leblanc et al., 2017), and a few combined them with geographic predictions (e.g. Ruegg et al., 2006; Wang et al., 2013), yet not providing spatially explicit hypotheses on the specific role of both the glacial and the interglacial periods in their diversification.…”

“…Despite the phenotypic variation documented for many of the species across their ranges (Engelmoer & Roselaar, 1998), most of them display a shallow genetic diversity and low differentiation between lineages or subspecies (e.g. Baker et al., 1994; Leblanc et al., 2017; Rönkä et al., 2012). This pattern has often been attributed to the population bottlenecks and very recent diversification during the Pleistocene glacial cycles (e.g.…”

Diet ofCalidris maritima(Purple Sandpiper) during the Winter in Nova Scotia, Canada

“…We conducted our sampling in a restricted window of opportunity at each location; thus, there may be some bias in our sampling, given that some marine invertebrates (notably mollusks) partition intertidal habitats (e.g., Feare 1966, MacDonald 1969 and are only available for portions of the tidal cycle (which may not match the time when we sampled). Furthermore, we did not assess whether Purple Sandpipers were actively foraging prior to collection; our priority was to obtain birds for a genetic study (Leblanc 2015), so the dietary examination was an opportunistic project added on to the primary research. We collected the birds with a 20-gauge shotgun using steel shot, and froze the carcasses at -20 °C within 12 h. We did not immediately pour ethanol into their digestive systems, so some soft-bodied prey could have been digested during this 12-h period.…”

“…As part of a project to examine aspects of the phylogeography of Purple Sandpipers wintering in coastal Nova Scotia (Leblanc 2015), we were interested in gathering better information on their diet. In particular, we wanted to determine if Purple Sandpipers specialized on any prey item in this region, as suggested by Smith and Bleakney (1969), or whether they typically had a more catholic diet irrespective of study site (as suggested by the studies above).…”