South Dakota fieldwork

During the end of the month, June 2026, I spent the week in South Dakota with Denver Museum of Nature and Science curator Garth Spellman. We went to the heart of the hybrid zone between Rose-breasted and Black-headed Grosbeaks with the intention of capturing these birds in mist nets and trying to better understand the dietary, behavioral, and genetic mechanisms of reproductive isolation between these two species. We found male grosbeaks that ranged the entire phenotypic spectrum from pure Black-headed through pure Rose-breasted, with some interesting phenotypic hybrids in the mix. We also captured female birds, whose ancestry will remain mysterious until we sequence their DNA. We took blood samples from these birds for genetic analysis and affixed metal bands on their legs so that we can identify recaptures in future years. The trip was a success and we’re looking forward to seeing what we can learn from the genetic data we’ve collected!