RNA-viromics unveils diverse RNA viral communities in Large-billed crows and Northern Ravens.

Birds have historically served as key vectors for viruses causing significant diseases. Corvid birds, often living in close proximity to livestock, poultry, and humans, provide substantial opportunities for cross-species viral transmission. Such transmission can occur through their feces or via ectoparasites (such as ticks, mites, and fleas) on their bodies, thereby releasing viruses into the environment. Despite the development of viral metagenomics, an increasing number of RNA viruses are being characterized across different species. RNA viruses in birds' gut microbial communities remain poorly studied. Here we report an extensive analysis of an RNA virome in fecal samples from Large-billed crows (Corvus macrorhynchos) and Northern Ravens (Corvus corax), both of which are common Corvus species found in the high-altitude forest and grassland regions of the Qinghai-Tibetan Plateau. This study aims to assess the RNA viruses present in the intestines of these corvids and provides the first comprehensive characterization of the diversity of gut-colonizing viruses in these two crow species.