Confirmation of Successful Chesnut-sided Warbler Breeding in South-Central Indiana

Abstract

Reported here is the first documented successful chestnut-sided warbler (Setophaga
pensylvanica) breeding attempt in south-central Indiana in 20 years. Although small breeding populations
have historically utilized available habitat in the southern half of the state, Indiana birders have only
recorded 22 chestnut-sided warbler sightings in this region during the breeding season (June—July) over the
last 35 years. Constant-effort mist-netting was used to monitor six, 7-year-old clearcuts in the Morgan
Monroe and Yellowwood State Forests (Morgan and Brown counties, IN) during the summer of 2015. Over
the course of the breeding season, 16 chestnut-sided warblers: seven males, five females (four with a brood
patch indicating breeding attempts), and four hatch-year birds (indicating successful breeding) were banded.
In addition to one other report of confirmed breeding in northern Indiana (Miami County), this is the only
confirmed chestnut-sided warbler breeding population in the state within the last decade. Breeding of
chestnut-sided warblers in 2015 demonstrates the value of maintaining some early successional habitat in
southern Indiana landscapes.