From city to canyon: A survey of blow fly biodiversity across Utah ecoregions

Blow flies (Diptera: Calliphoridae) are primary colonizers of animal remains and play a crucial role in decomposition, making them valuable for estimating the time of colonization (TOC) in forensic investigations and a potential monitor for wildlife. However, little is known about the species composition and distribution of blow flies in the Mountain West, particularly in Utah. To address this gap, our research focuses on the collection, preservation, and identification of blow flies across various locations in Utah. Since 2023, collections have been made across the state of Utah in both urban (Salt Lake City, Orem) and rural (Grand Gulch, Colorado Plateaus) environments. Traps baited with different carrion sources (chicken liver, beef liver, chicken breast, and pork chop) were deployed, collecting more than 300 Calliphoridae from at least three genera: Calliphora, Lucilia, and Phormia. Lucilia species are most prevalent in our urban collections, while Phormia regina dominates our rural collections. Collecting efforts have been expanded, emphasizing ecoregions and environments that remain unsampled. Using standard diversity metrics, species composition is compared across locations, and the impact of bait sources and timing is investigated. Our findings provide valuable insights into the biodiversity and distribution of blow flies in different ecoregions across Utah. This research not only enhances our ecological understanding of Calliphoridae in understudied regions but also has significant applications in forensic science and conservation.