Identification of Porrocaecum moraveci in red kites in England and Wales, a species of conservation concern.

The population of free-living red kites (Milvus milvus [Linnaeus 1758]) in England and Wales has increased since 1989 as a consequence of species reintroduction. The red kite, however, remains of conservation concern, with populations in Europe considered to be in decline. Plans to translocate birds from England to Spain have been initiated, prompting consideration of the disease risks associated with the translocation of parasites which may be present within the source population. This study utilized published morphological markers and molecular polymerase chain reaction techniques to identify archived adult helminth parasites extracted from the gastrointestinal tract of red kites found dead and examined post-mortem in England and Wales between 2014 and 2021. Helminths of the genus Porrocaecum (Railliet and Harry 1912) were identified in 22 out of the 23 helminth-infected red kites from a wide geographical distribution, suggesting that this parasite is common in the red kite population in England and Wales. Molecular characterization using internal transcribed spacer 2 (ITS-2) and 28S rDNA sequences identified Porrocaecum moraveci (Gu et al. 2023), the first report of this recently described species in the UK. Ascaridia (Dujardi 1845) sp., Capillaria (Zeder 1800) sp., and Syngamus trachea (Montagu 1811) ova were also detected during the post-mortem examinations (PMEs) and are known to be present within European red kite populations, suggesting that these parasites do not represent a novel disease risk to the destination population in Spain. Previous reports of Porrocaecum angusticolle (Molin, 1860) in British and other European red kite populations should now be revisited to confirm identity and assess the risk of parasite translocation.