Lab News
Vermivora Surveys 2025
Excellent team of field techs are conducting point counts in western Virginia this spring. Baxter Beamer is in Highland/Bath Counties while Catelin Greiman and Ben Yeasting are in southwest Virginia (Tazewell and surrounding counties). They are for the most part replicating surveys that occurred throughout the last 10 years so that we can assess changes in occupancy for Vermivora warblers over time and across changes in habitat.
Is caterpillar biomass affected by invasive shrubs?
Abby Bressette, undergraduate researcher in the lab, is assessing caterpillar biomass on focal trees known to be preferred for foraging by migratory warblers. She is interested in whether there will be fewer caterpillars when the trees are surrounded by nonnative invasive vegetation (autumn olive, barberry, multiflora rose) vs native vegetation (blackberry). This research was motivated by Sam Fishman's recent thesis results on warbler foraging as well as conversations with landowners that struggle with controlling the nonnative invasive shrubs but want to maintain habitat for shrubland birds.
Sam Fishman defended her thesis
Sam's thesis assessed foraging behavior in Golden-winged (GWWA) and Chestnut-sided Warblers (CSWA) on private working lands in Highland County Virginia. She found GWWA prefer hawthorn and locust as foraging substrates; specifically they spend more time and attack more often on these plants than expected based on their availability. CSWAs prefer to forage on cherry.
Both bird species avoid nonnative shrubs (autumn olive, barberry, and multiflora rose).
Pete's paper is published in Ornithology
Pete Peterson (BS, ENVS May 2024) published his undergraduate research in Ornithology. He compiled data from across 1,036 clutches spanning 22 years, and found that low temperatures, young mothers, and small clutch sizes contributed to longer incubation periods. These results indicate that advancements in breeding expose clutches to colder and more variable temperatures, resulting in longer incubation periods, but this effect is likely mitigated by larger clutches and a higher proportion of older females in the early season.
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