Multiscale nest‐site selection of ducks in the western boreal forest of Alberta

Abstract

There is limited data regarding the nesting ecology of boreal ducks and their response to industrial development, despite this region being an important North American breeding area. We investigated how landcover and oil and gas development affect third‐order nest‐site selection of boreal ducks. We located duck nests in Alberta's western boreal forest between 2016 and 2018. We used multiscale analysis to identify how scale affects the selection of a resource using generalized linear mixed‐effects models and determined what scale‐optimized combination of landscape features were most important in describing where ducks nest. We located 136 nests of six species of upland nesting ducks between 2016 and 2018. The magnitude, direction, and best spatial scale varied by resource. For landcover, ducks selected nest‐sites associated with mineral wetlands (300 m) and open water (300 m). Ducks avoided greater densities of seismic lines (300 m) and pipelines (2500 m) but selected nest‐sites associated with borrow pits (300 m) and roads (1000 m). We used our models to predict important duck nesting habitat in the boreal forest, which can support conservation and management decisions. We recommend conservation actions target the conservation of mineral wetlands and associated habitats within this working landscape. Further research is necessary to understand the adaptive consequences of nest‐site selection and how industrial development influences important nest predators.

Multi‐level habitat selection of boreal breeding mallards

“…Marsh was a grouped variable (Table 1), which characterized the transition zone between shrub swamp, graminoid fen, open water areas, and forests (Smith et al 2007). Female mallards selected marsh habitat across scales and these results were consistent with Dyson (2020) who demonstrated boreal ducks selected nest sites with greater marsh cover within 300 m of the nest. This is likely attributed to the foraging, resting, and nesting opportunities that marshes provide for ducks (Pearse et al 2012, Beatty et al 2014 b , Stafford et al 2016).…”

“…Selection for shrub swamps is consistent with the limited available research; however, the avoidance of swamps was surprising given previous research that suggested ducks settling in the eastern boreal forest prefer wetlands with swamp peripheries over shrub swamp peripheries (Lemelin et al 2010). In terms of nest site selection in the region, nesting ducks exhibited a scale‐dependent response and avoided swamps at coarse scales, but selected swamps at fine spatial scales (Dyson et al 2022). We suspect that shrub swamps provided forage opportunities (Straub et al 2012) and dense vegetative cover for concealment from predators.…”

“…Next, we only included locations that fell within the western boreal forest (Prairie Habitat Joint Venture 2014). We then estimated a breeding period cut‐off date (13 September) by determining the latest estimated nest initiation date (15 June) using boreal mallard nesting data from 2016–2018 (Dyson 2020). Our estimated cut‐off was consistent with Raquel et al (2016), who suggested about 95% of prairie nesting mallards have initiated their nest by 17 June.…”

“…Habitat selection occurs annually during the non‐breeding (Bengtsson et al 2014, Beatty et al 2017, Meattey et al 2019, Palumbo et al 2019), and breeding periods (Johnson and Grier 1988, Yerkes 2000, Doherty et al 2015, Singer et al 2020, Kemink et al 2021). The breeding period represents a temporal scale and an important stage in the annual cycle of ducks when habitat structure and composition can influence reproduction and survival of nests, broods, and adults (Simpson et al 2007, Boyer et al 2018, Roy 2018, Skaggs et al 2020, Dyson et al 2022). A majority of breeding habitat selection research for ducks is in prairie (Gloutney and Clark 1997, Murkin et al 1997, Clark and Shutler 1999, Yerkes 2000, Ludlow and Davis 2018) and arctic regions (Robertson 1995, Pratte et al 2016, Gerall 2019, Lamb et al 2020), and focuses on third‐ and fourth‐order selection at specific phases of the breeding period (e.g., nest and brood sites).…”

“…A majority of breeding habitat selection research for ducks is in prairie (Gloutney and Clark 1997, Murkin et al 1997, Clark and Shutler 1999, Yerkes 2000, Ludlow and Davis 2018) and arctic regions (Robertson 1995, Pratte et al 2016, Gerall 2019, Lamb et al 2020), and focuses on third‐ and fourth‐order selection at specific phases of the breeding period (e.g., nest and brood sites). Thus, we have a limited understanding of coarse‐order breeding habitat selection in ducks (Johnson and Grier 1988, Krapu et al 1997), and we have considerably less knowledge regarding breeding habitat selection of boreal ducks (Holopainen et al 2015; Dyson et al 2019, 2022; Singer et al 2020).…”