With the 2019 field season in the books (and Mountain Bluebirds from our nestboxes showing up as far south as Ft. Worth, Texas), November is a great time to cozy up by the fire and reflect on the robust, scientific data gathered during this year’s monitoring program!
This season was our third consecutive year banding Mountain Bluebird nestlings on the National Elk Refuge (NER) with identifiable colored-bands. It also marked our 16th straight year engaging volunteers to help monitor Mountain Bluebird Nestboxes on the NER nestbox trail!
We will likely remember the 2019 field season for its uncommonly cold spring and relatively low rates of bluebird nestling success compared to previous seasons.*
We can report success in banding another “cohort” of nestlings and having 4 banded birds from previous years resighted in Jackson Hole this year.
- Volunteers and JHWF staff successfully monitored 112 nestboxes along the western edge of the NER this nesting season.
- The Mountain Bluebird nestbox-occupation rate was only 11% this season. The 89% of nestboxes that were unused by bluebirds were either left unoccupied our utilized by Tree Swallows or occasionally by House Wrens.
- JHWF professional bird banders placed identifying colored-bands on 43 nestling bluebirds. This number was down from 72 in 2018 and 85 in 2017; however, as the number of banded birds grows, we expect the number of “resighted” birds to increase reach summer.
- Ten (10) adult Mountain Bluebirds which hatched in NER nestboxes have been “resighted” since banding began in 2017. This includes 4 resights made in 2019. Deceased birds account for 2 of the 10 resightings; one banded bird was hit by a car near the National Museum of Wildlife Art while another struck a window near Tribal Trails.
- Several bluebird nests were predated (likely by weasels or raccoons) and/or were abandoned in 2019. We now installed safeguards on 25 nest boxes with a history of invasion, which we hope will deter predators in 2020 and beyond!
To learn more about our Mountain Bluebird Nestbox Monitoring Project, follow this link.
*It’s possible the prolonged cold snap played a role in reducing the rate of successful nests we saw this year. Further explanation is provided in the report.