Autumn migration of Jack Snipe Lymnocryptes minimus in southern Sweden: results from ten years of crepuscular ringing

Adam Bergner,Lars Gezelius,Christer Elderud,Kent Person

doi:10.34080/os.v31.22319

Abstract

The autumn migration of Jack Snipe Lymnocryptes minimus was studied using mist-netting at night along a muddy shoreline at Lake Tåkern in southern central Sweden. During ten consecutive autumn seasons ranging from mid-September to mid-November a total of 107 birds were captured, particularly within the first two hours after dusk. The peak of migration occurred in the first ten days of October with the juvenile birds on average passing a few days earlier than the adult birds. We present information on movements and ringing recoveries and review the challenges of ageing the species. We propose that crepuscular mist-netting near wetlands offering important staging grounds may be a suitable method to monitor the migratory movements, and possibly the population dynamics, of this little-studied species.

Highlights

The Jack Snipe Lymnocryptes minimus is a small wader Simmons 1983)
The species is at least 90 %, is believed to breed in Russia, and since scarcely observed in systematic monitoring large parts of the species’ distribution range is con- programs in its main breeding habitats (e.g. Lindström fined to areas lacking permanent human settlements et al 2015)
As the water level in the lake is artificially lowered by 20–25 cm in the autumn, the mudflats that are attractive for foraging waders increase in size

Summary

Introduction

The Jack Snipe Lymnocryptes minimus is a small wader Simmons 1983). The species is generally migratory and breeding in boreal mires and wet tundra from northern exhibits a migratory divide near the 45°E longitude, Fennoscandia northeast to eastern Siberia Its current status and population plumage coloration (Sikora 2005; Figure 1) as well as its reluctance to fly in daylight (Olivier 2007). These circumstances have created major challenges for appropriate methods of capturing birds for ringing (Lepley et al 2005). Jack Snipe in active flight is when the birds move from resting sites to foraging sites during crepuscular flight (Le Bobinnec 1976). Having experienced this phenomenon at Lake Tåkern a few times back in the 1960s and 1970s, we once again set out to try capturing. Of the occurrence and migratory movements of this littlestudied species at a stopover location during autumn migration

Methods

Results

Discussion