Migratory connectivity of American woodcock derived using satellite telemetry

Abstract

American woodcock (Scolopax minor; woodcock) migratory connectivity (i.e., association between breeding and wintering areas) is largely unknown, even though current woodcock management is predicated on such associations. Woodcock are currently managed in the Eastern and Central management regions in the United States with the boundary between management regions analogous to the boundary between the Atlantic and Mississippi flyways, based largely on analysis of band returns from hunters. Factors during migration influence survival and fitness, and existing data derived from banding and very high frequency telemetry provide only coarse‐scale information to assess factors influencing woodcock migratory movement patterns and behavior. To assess whether current management‐region boundaries correspond with woodcock migratory connectivity in the Central Management Region and to describe migration patterns with higher resolution than has been previously possible, we deployed satellite transmitters on 73 woodcock (25 adult and 28 juvenile females, and 8 adult and 12 juvenile males) and recorded 87 autumn or spring migration paths from 2014 to 2016. Marked woodcock used 2 primary migrations routes: a Western Route and a Central Route. The Western Route ran north‐south, connecting the breeding and wintering grounds within the Central Management Region. The hourglass‐shaped Central Route connected an area on the wintering grounds reaching from Texas to Florida, to sites throughout northeastern North America in both the Eastern Management Region and Central Management Region and woodcock following this route migrated through the area between the Appalachian Mountains and the Mississippi Alluvial Valley in western Tennessee during autumn and spring. Two of 17 woodcock captured associated with breeding areas in Michigan, Wisconsin, or Minnesota migrated to wintering sites in the Eastern Management Region and 12 marked woodcock captured on wintering areas in Texas and Louisiana migrated to breeding sites in the Eastern Management Region. Woodcock that used the Western Route exhibited high concentrations of stopovers during spring in the Arkansas Ozark Mountains and northern Missouri, and along the Mississippi River on the border between Wisconsin and Minnesota, and autumn concentrations of stopovers in southwestern Iowa, central Missouri, the Arkansas portion of the Ozark Mountains, and around the junction of Texas, Louisiana, Oklahoma, and Arkansas. Woodcock that used the Central Route exhibited high concentrations of stopovers during spring in northern Mississippi through western Tennessee, western Kentucky, and the Missouri Bootheel, and autumn concentrations of stopovers in northern Illinois, southwestern Ohio, and the portions of Kentucky and Tennessee west of the Appalachian Mountains. We suggest that current management of woodcock based on 2 management regions may not be consistent with the apparent lack of strong migratory connectivity we observed. Our results also suggest where management of migration habitat m...

A comparison of methods for the long-term harness-based attachment of radio-transmitters to juvenile Japanese quail (Coturnix japonica)

“…This suggests that this combination of harness type and material is problematic unless the Elastic cord can be run through a small tube that reduces contact between the material and the skin. While such an approach has been used successfully with American Woodcock [33], this would be problematic with species such as terns that regularly dive, as the tubes would fill with water increasing harness weight and resistance.…”

The American Woodcock Singing Ground Survey largely conforms to the phenology of male woodcock migration

“…Because some woodcock reproduction occurs both north and south of the SGS coverage area, some have questioned whether the current geographic scope of the survey is adequate (Whiting 2010, Sullins et al 2016). Various attempts have been made to assess the survey accuracy considering these and other potential issues (Nelson and Andersen 2013, Tavernia et al 2018, Bergh and Andersen 2019, Moore et al 2019. Satellite tracking provides a new and potentially useful approach, which Moore et al (2019) recently used to show a non-trivial number of woodcock continued migration during the SGS survey period.…”

“…Various attempts have been made to assess the survey accuracy considering these and other potential issues (Nelson and Andersen 2013, Tavernia et al 2018, Bergh and Andersen 2019, Moore et al 2019. Satellite tracking provides a new and potentially useful approach, which Moore et al (2019) recently used to show a non-trivial number of woodcock continued migration during the SGS survey period. Transmitter mass available at the time of study prevented Moore et al (2019) from marking a large sample of male woodcock, which are smaller-bodied than females (McAuley et al 2020).…”

“…Satellite tracking provides a new and potentially useful approach, which Moore et al (2019) recently used to show a non-trivial number of woodcock continued migration during the SGS survey period. Transmitter mass available at the time of study prevented Moore et al (2019) from marking a large sample of male woodcock, which are smaller-bodied than females (McAuley et al 2020). More comprehensive studies based on larger sample sizes of males marked with satellite transmitters are needed (Moore et al 2019).…”

“…Transmitter mass available at the time of study prevented Moore et al (2019) from marking a large sample of male woodcock, which are smaller-bodied than females (McAuley et al 2020). More comprehensive studies based on larger sample sizes of males marked with satellite transmitters are needed (Moore et al 2019).…”