Current knowledge of helminth parasites in Australian Anatidae species

Research on parasites in Australian birds is limited. This study aimed to identify patterns of parasite burdens and their distribution across Australia in Anatidae species. Data were gathered from databases and the Australian Helminth Collection, then analysed using a Microsoft Excel spreadsheet. The findings reveal that platyhelminths were more frequently reported than nematodes, while acanthocephalans were the least abundant and least diverse parasites. At least 119 parasitic helminth taxa were recorded in Australian Anatidae (22 species from 16 genera), based on 271 records from 44 published articles and five museum/research institution collections. Specifically, 76 cases of nematode infection (33 taxa) were found among 20 Anatidae species, 102 cases of trematode infection (42 taxa) among 22 species, and 90 cases of cestode infection (40 taxa) among 16 species. The high prevalence of platyhelminths may be due to the host diet and the parasites’ ability to multiply asexually in various larval stages among trematodes, increasing the likelihood of exposure and infection. The study also highlights the challenges in accurately identifying parasites due to many records being identified only at higher taxonomic levels. This issue is exacerbated by a scarcity of taxonomists and insufficient investment in capacity building in the country. Moreover, the available knowledge about the geographical distribution of Anatidae parasites in Australia is biased by the location of research institutions rather than the actual distribution of parasites. The introduction of non-native parasites through bird movement and introduced domestic waterfowls across borders poses a significant risk to native wildlife, potentially leading to new disease outbreaks or exacerbating existing health issues.