A mist‐net method for capturing harlequin ducks on rivers

Abstract

ABSTRACTMany sea ducks are captured during wing molt at intertidal areas; however, to study the breeding ecology of some species, researchers need to capture them on streams and rivers, which are often flowing with high water. In fast‐flowing and deep water, wading streams during net set‐up and extraction of birds is impossible to complete safely. Between 1995 and 2013, we captured 720 adult and 241 hatch‐year harlequin ducks (Histrionicus histrionicus) on 37 streams in eastern and western North America. We used a mist net extended across the stream with modified riggings that allowed above‐water retrieval of captured birds without technicians entering the stream. This method can be used across deep, fast water that is not wadable; requires equipment that is compact and easily transported; is suitable for remote areas; can be operated by a crew of 4–6 people; and has a low risk of injury to the birds. Care must be taken when using this method to capture large numbers of ducks simultaneously because it becomes difficult to keep the birds above the fast water. This capture method could be used for other ducks, and with different mesh sizes could also be used for other birds, such as American dippers (Cinclus americanus) and spotted sandpipers (Actitis macularius), at these inland locations. The mobility of this capture method means that species and individuals that are not of interest can be avoided by orienting the net to a horizontal position to allow non‐target species to pass by unhindered. © 2015 The Wildlife Society.