https://phaidra.vetmeduni.ac.at/o:5271 Chromosome-level genome assembly and transcriptome analysis of the Ural owl, Strix uralensis Pallas, 1771 Winter, Sven Sven Winter 0000-0002-1890-0977 University of Veterinary Medicine Vienna Meißner, René René Meißner 0000-0003-2829-1607 University of Veterinary Medicine Vienna Grethlein, Martin Martin Grethlein 0000-0001-9330-8554 Wehrenberg, Gerrit Gerrit Wehrenberg 0000-0003-4828-3057 Kiebler, Angelika Angelika Kiebler 0009-0001-2762-5057 Silva, Andrea X Andrea X Silva 0000-0002-4346-5524 Escobar, Natalia Reyes Natalia Reyes Escobar 0009-0001-5286-4164 Quesada Calderón, Suany M Suany M Quesada Calderón 0000-0003-3963-146X Suescún, Ana V Ana V Suescún 0000-0003-2575-8873 Belmar, Luis Guzman Luis Guzman Belmar 0009-0002-2356-0150 Prost, Stefan Stefan Prost 0000-0002-6229-3596 Oxford University Press journal article open access eng The Ural owl (Strix uralensis) is a large member of the Strigidae family and inhabits Eurasian forests from Germany to Japan. However, it faces increased range reduction, particularly at its southwestern distribution edges. Despite being considered “Least Concern” by the IUCN, local populations have become threatened in Central Europe due to severe habitat loss. Reintroduction programs aim to restore these populations by closing distribution gaps and facilitating natural recolonization of suitable habitats. To support these efforts, genomic resources have become an established tool to assess genetic diversity, geographic structure, and potential inbreeding, crucial for maintaining the genetic health and adaptability of newly established populations. Here, we present a de novo genome assembly and transcriptome of the Ural owl based on ONT long-reads, Omni-C Illumina short-reads, and RNASeq data. The final assembly has a total length of 1.26 Gb, of which 96.42% is anchored into the 42 largest scaffolds. The scaffold and contig N50 values of 88.65 Mb and 21.74 Mb, respectively, a BUSCO/compleasm completeness of 97.5%/99.65% and k-mer completeness of 95.18%, emphasize the high quality of this assembly. Furthermore, annotation of the assembly identified 17,650 genes and a repeat content of 12.48%. This new highly contiguous and chromosome-level assembly will greatly benefit Ural owl conservation management by informing reintroduction programs about the species’ genetic health and contributing a valuable resource to study genetic function in greater detail across the whole Strigidae family. Conservation Omni-c Oxford Nanopore Proximity Ligation Strigidae http://creativecommons.org/licenses/by-nc/4.0/ https://phaidra.vetmeduni.ac.at/api/object/o:5271/download 10.1093/jhered/esaf038 https://phaidra.vetmeduni.ac.at/o:605 application/pdf Journal of Heredity issn:0022-1503 VoR Journal of Heredity 117 1 1.24 MB 2026