Microhabitat nest‐site selection by ducks in the boreal forest

 

The boreal forest is one of the most important breeding areas for ducks in North America, but there is little information about the nest ecology of ducks from this region. New research just published in The Journal of Field Ornithology reveals microhabitat nest-site selection strategies of five species of boreal ducks from two nesting guilds.

Nests were located by field crews that searched on foot around wetland edges through various landcover types in Alberta’s boreal forest. The researchers located 167 nests from 2016 to 2018 and collected microhabitat data at 157 nests of 8 different species, including American Wigeon, Blue-winged Teal, Canvasback, Green-winged Teal, Lesser Scaup, Mallard, Northern Shoveler, and Ring-necked Duck. Nests were monitored and vegetation measurements were conducted at nests and a paired random location following the determination of nest fate.

Overall ducks consistently selected for overhead cover. The research also revealed resource partitioning between guilds and among species through variation in the composition of vegetation groups selected, which likely facilitates regional coexistence. The selection patterns observed were consistent with an optimization strategy used by nesting females that maximizes overhead concealment, while allowing for detection and escape from terrestrial predators.

The researchers specifically investigated patterns of nest-site selection to help understand the choice that ducks were making relative to what is available. This information is not otherwise available in studies of nest survival that compare successful to unsuccessful sites. Understanding patterns of selection provides a foundation to make predictions for future work regarding nest success in the boreal forest.

 

Blue-winged Teal nest on a sphagnum mat among sedges.

Mallard nest in a willow thicket.

 

This research was recently published in the Journal of Field Ornithology:

Dyson, M. E., S. M. Slattery, and B. C. Fedy. 2019. Microhabitat nest‐site selection by ducks in the boreal forest. Journal of Field Ornithology https://doi.org/10.1111/jofo.12314.

 

Guest post by:

Matt Dyson, AWB®, MSc
PhD Candidate
School of Environment, Resources and Sustainability
University of Waterloo
https://uwaterloo.ca/scholar/bfedy
Twitter: @DysonWildlife