2020 Woody Draw Songbird Research Report | MPG Ranch

2020 Woody Draw Songbird Research Report

January 29, 2021

This UMBEL report summarizes 2020 field effort and shares long-term songbird breeding trends in restored and untreated woody draws.

2020-12-30_AN-1.jpg

2020 Woody Draw Songbird Research

2020-12-30_AN-2.jpg

In 2020, we delineated 254 breeding territories, located and monitored 172 nests, and recorded 15 nesting attempts using video cameras.

2020-12-30_AN-3.jpg

We focused on five bird species that commonly nest in woody draws in the Bitterroot Valley: dusky flycatcher, gray catbird, lazuli bunting, orange-crowned warbler, and spotted towhee.

2020-12-30_AN-4.jpg

We found 172 nests from five species.

2020-12-30_AN-5.jpg

We visited nests every three to four days to determine the fate of nestlings.

2020-12-30_AN-6.jpg

We placed solar-powered video cameras at 15 nests to record sources of nest failure and identify predators.

2020-12-30_AN-7.jpg

Lower densities and larger territory sizes indicate that, while habitat is improving with restoration, these draws remain lower quality habitat for breeding songbirds.

2020-12-30_AN-8.jpg

Our analyses of annual nest survival reveal far lower nest success than we expected.

2020-12-30_AN-9.jpg

We suspect differences in nest parasitism by brown-headed cowbirds help explain the variation in survival we found among species.

2020-12-30_AN-10.jpg

Depredation was the single largest source of nest failure for spotted towhee and lazuli bunting nests found in 2020.

2020-12-30_AN-11.jpg

This year, we recorded eight predation events by five different predator species at six nests using video cameras.

2020-12-30_AN-12.jpg

We recorded two predation attempts by western racers on lazuli bunting nests.

2020-12-30_AN-13.jpg

Songbird breeding activity is booming in both restored and untreated woody draws on MPG Ranch. We think this widespread upswing is likely due to the cumulative benefits of restoration and land management practices across MPG Ranch, not just in the draws.

2020-12-30_AN-14.jpg

dusky flycatcher breeding territories we mapped in 2020

2020-12-30_AN-15.jpg

gray catbird breeding territories we mapped in 2020

2020-12-30_AN-16.jpg

lazuli bunting breeding territories we mapped in 2020

2020-12-30_AN-17.jpg

spotted towhee breeding territories we mapped in 2020

2020-12-30_AN-18.jpg

orange-crowned warbler breeding territories we mapped in 2020

Previous Research Report

2020 Intermountain Grassland Songbird Project Report