Weather conditions affect spring and autumn migration of Siberian leaf warblers

Abstract

Background: Weather effects on bird migration are well-studied among Passerines moving from Europe to Africa or within the American flyway systems. However, little is known about the weather impact on songbirds migrating along the East Asian flyway. Our study aims to describe the effects of various weather elements on the migration of four species of leaf warblers by using bird ringing data from a stopover site in Far East Russia. Methods:We determined the migration periods for each species and included maximum temperature, precipitation, air pressure, wind speed and wind direction in general linearized mixed models to predict the number of migrating birds. Results:We found strong impacts of weather variables on the number of trapped warblers during spring and autumn migration. Preferred or avoided weather conditions were similar among the studied species. All species seem to migrate preferably during warm, calm days without precipitation. A positive effect of tail winds was only confirmed in autumn, but in spring, most birds were trapped during crosswinds (eastern or western winds). Conclusion:The studied species might exhibit a loop migration, leading to a more longitudinal (from east to west) migration pattern in our study area during spring. Relationships between weather variables and the number of migrating individuals were much stronger during autumn. We argue that birds during spring migration would continue migration under sub-optimal conditions, as a result of strong competition to arrive earliest on their breeding grounds.

Factors controlling the migration phenology of Siberian Phylloscopus species

“…However, in the last two decades the most studied group in Asia were the leaf warblers. We have detailed information on breeding ecology (e.g., Price and Jamdar 1991;Bourski and Forstmeier 2000;Forstmeier et al 2001a;Forstmeier 2002;Forstmeier and Balsby 2002), habitat use, morphology and foraging strategies (Price 1991;Forstmeier et al 2001b;Katti and Price 2003;Batova 2011;Bozó et al 2018a), the sex-specific timing of migration (Bozó and Heim 2016), the effect of weather variables on the migration (Bozó et al 2018b) and the estimated migration distances (Sander et al 2017;Bozó et al 2019) of these species. However, the factors that influence the observed differences in migration phenology have not been studied yet.…”

Seasonal and diurnal increases in energy stores in migratory warblers at an autumn stopover site along the Asian–Australasian flyway

“…Although this is of course a simplification, this approach seems feasible, because songbirds are known to generally time their departure from stopover to coincide with favourable wind conditions (Dierschke and Delingat 2001;Erni et al 2002;) and also adjust their flight altitude to these (Schmaljohann et al 2009;Shamoun-Baranes et al 2017). Most of the studied warbler species were found to migrate mostly with favourable winds at our study site (Bozó et al 2018a). Negative flight range estimates were set to zero.…”

“…Although there are many studies that have investigated the movement ecology of migratory birds along the Asian-Australasian flyway, including storks (Shimazaki et al 2004;Higuchi 2012), raptors (Higuchi 2012), cranes (Higuchi et al 2004), waders (Takekawa et al 2010;Reid et al 2013;Bellio et al 2017), gulls (Guo-Gang et al 2014), and songbirds (Koike et al 2016;Yamaura et al 2017;Heim et al 2018a), the knowledge with respect to how songbirds behave at stopover sites (locations where they rest and fuel between their migratory flight bouts) has increased only slowly along this flyway. Although many field studies have significantly contributed to this research area (e.g., Valchuk et al 2005;Wang et al 2006;Biserov and Medvedeva 2009;Fukai et al 2010;Nam et al 2011;Leliukhina and Valchuk 2012;Yong et al 2015Yong et al , 1998Sander et al 2017;Senda et al 2018;Bozó et al 2018a;Heim et al 2018b), there is still a strong bias in terms of number of studies and therefore general knowledge of songbirds' stopover ecology towards the Nearctic and the Palaearctic-African flyway. Since songbird migrants spend far more time and energy during stopover than during migratory flights (Wikelski et al 2003;Schmaljohann et al 2012), we can learn from stopover ecology studies how songbirds organise their migratory journey in terms of these two currencies, reviewed e.g.…”

The State of Migratory Landbirds in the East Asian Flyway: Distributions, Threats, and Conservation Needs

“…On the other hand, no significant differences between spring and autumn migration speed/duration are evident in non-passerines, e.g., in satellitetracked Oriental honey buzzard Pernis ptilorhynchus (Yamaguchi et al, 2008) and great bustard Otis tarda (Kessler et al, 2013). In addition, specific morphological and behavioral adaptations have been found across various model species in the EAF that improve the efficiency of long migratory flights (Bozó et al, 2018a;Wang et al, 2020).…”