Summary report for surveys of riparian passerine assemblages conducted in Yukon-Charley NP and Gates of the Arctic NP, 2013-2014

Mizel, Jeremy

The Arctic and Central Alaska Networks identified monitoring of landbird assemblages as important to assessing local and broad-scale ecological patterns within network parks (MacCluskie 2005, Lawler et al. 2009). In the Central Alaska Network (CAKN), landbird monitoring has been conducted in Denali National Park since 1992 and, more recently, in Wrangell-St. Elias National Park. In seeking to expand this program to Yukon-Charley Rivers National Preserve (YUCH), CAKN identified monitoring of riparian passerine assemblages along the Yukon River as the focus of this effort and then implemented this work in 2013. Through the influence of fire and hydrologic disturbance regimes, boreal forest floodplains, including those of the Yukon River, are highly dynamic systems (Butler et al. 2007). Aerial insectivorous birds, many of which are disturbance-adapted, are a large component of the passerine community along the Yukon River in YUCH. Monitoring of this passerine community holds particular importance given predominantly negative trend estimates from the Breeding Bird Survey (BBS) among aerial insectivorous passerines (Nebel et al. 2010, Sauer et al. 2012). With the intention of sampling a similar suite of species and integrating landbird monitoring across networks, the Arctic Network (ARCN) conducted a pilot survey of riparian passerine assemblages along the North Fork of the Koyukuk (hereafter, North Fork), Gates of the Arctic National Park (GAAR), in 2014. Objectives for this combined effort included documenting temporal trends in occupancy and abundance of riparian-breeding passerines.