Diversity and distribution of ectoparasites infesting Podiceps cristatus and Tachybaptus ruficollis (Aves, Podicipediformes) at a Ramsar site in northeast Algeria: new records.

Travaux du Muséum National d’Histoire Naturelle “Grigore Antipa” 68 (2): 329–345 (2025) doi: 10.3897/travaux.68.e160040 RESEARCH ARTICLE Diversity and distribution of ectoparasites infesting Podiceps cristatus and Tachybaptus ruficollis (Aves, Podicipediformes) at a Ramsar site in northeast Algeria: new records Miyyada Khalfallah1, Nada Nouri1, Amel Lazli1, Rozalia Magda Motoc2, Bilal Dik3, Leila Ouarti1, Faiza Marniche4 1 Chadli Benjedid University, Faculty of Natural and Life Sciences, Department of Biology, El-Tarf, Algeria 2 “Grigore Antipa” National Museum of Natural History, 1 Kiseleff, 011341 Bucharest, Romania 3 Beyhekim Mah, Karakoçlar Sokak, Koza Sitesi 18/12, Selçuklu, Konya, Türkiye 4 National Veterinary School (ENSV) El Alia, Algies, Algeria Corresponding author: Miyyada Khalfallah () Received 24 May 2025 | Accepted 15 December 2025 | Published 31 December 2025 Citation: Khalfallah M, Nouri N, Lazli A, Motoc RM, Dik B, Ouarti L, Marniche F (2025) Diversity and distribution of ectoparasites infesting Podiceps cristatus and Tachybaptus ruficollis (Aves, Podicipediformes) at a Ramsar site in northeast Algeria: new records. Travaux du Muséum National d’Histoire Naturelle “Grigore Antipa” 68(2): 329–345. https://doi.org/10.3897/travaux.67.e160040 Abstract Algeria hosts 55 Ramsar sites of international significance, serving as crucial habitats for a wide range of migratory, wintering, and breeding waterbird species. Despite this, research on the ectoparasites of aquatic avifauna in Algeria remains limited. This study aims to investigate the ectoparasite diversity infesting the Little Grebe (Tachybaptus ruficollis Pallas, 1764) and the Great Crested Grebe (Podiceps cristatus Linnaeus, 1758) in northeastern Algeria. To do so, we examined grebes of both species at Lake Tonga between 2022 and 2023. A total of 8,057 ectoparasites were collected, 24 of which belonged to Phthiraptera and 8,033 to Acari. Two lice species were identified: Aquanirmus podicipis Denny, 1842, belonging to the suborder Ischnocera, infesting the Great Crested Grebe and Pseudomenopon dolium Rudow, 1869, from the suborder Amblycera, infesting the Little Grebe. As for Acari, we identified two mite species belonging to the suborder Astigmata (Pterolichoidea; Ptiloxenidae): Ptiloxenus major Mégnin & Trouessart, 1884, and Ptiloxenus colymbi Canestrini, 1878 the latter of which had not been reported since its original description. This study reports a new host-parasite association in the global mite fauna (Great Crested Copyright Khalfallah, Nouri, Lazli, Motoc, Dik, Ouarti & Marniche. This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. 330 Khalfallah, Nouri, Lazli, Motoc, Dik, Ouarti & Marniche Grebe - Ptiloxenus colymbi Canestrini, 1878). All the identified ectoparasite species are reported for the first time in Algeria. Feather mite infestation did not differ significantly between breeding and wintering seasons and showed only a weak correlation with host morphometric parameters. These findings suggest that neither season nor body size strongly influence feather mite dynamics in the studied grebes, while still providing valuable insights into their host–parasite relationships. Keywords Feather mites, Great Crested Grebe, Lake Tonga, lice, Little Grebe. Introduction The symbiotic relationship between wild birds and parasites, including mites, ticks, lice, and fleas has been a subject of considerable interest in ecological research (Clayton et al. 2010). Ectoparasites can serve as vectors for a wide range of avian diseases, transmitting parasitic, rickettsial, bacterial, and viral infections between domestic and migratory birds. Additionally, they can cause allergic reactions, irritation, anorexia, reduced productivity in affected birds, and myiasis, all of which can impact the health and fitness of avian populations (Zumpt 1965; Dik 2006). Understanding the interactions between birds and their ectoparasites is essential for comprehending broader ecological dynamics, as these relationships can significantly influence both host populations and parasite communities. Furthermore, this knowledge has implications for wildlife conservation and management, given that ectoparasites are integral to a larger ecological network involving multiple host species. Situated within the Mediterranean basin, Algeria plays a crucial role in avian migration, wintering, and breeding. The country hosts 55 Ramsar sites, more than any other African nation, providing vital habitats that attract large populations of waterbirds on a regular basis (Isenmann and Moali 2000; Samraoui and Samraoui 2008; Samraoui et al. 2011). In northeastern Algeria, avian populations have been documented to include 61 species across 17 families and 44 genera. Among these, the family Podicipedidae (grebes) is represented by three species, all classified as Least Concern (LC) in terms of conservation status (BirdLife International. 2018, 2019a,b; Gherib et al. 2021). The Little Grebe (Tachybaptus ruficollis) and the Great Crested Grebe (Podiceps cristatus) are resident breeders at Lake Tonga (Loucif et al. 2020; Mecif and Boucheker 2020). These species are recognized as excellent bioindicators of the structure and functioning of aquatic ecosystems (O’Donnell and Fjeldså 1997; Fjeldså 2004). However, despite their ecological significance, relatively few studies have examined avian parasites in Algeria. Existing research has primarily focused on the parasite diversity of domestic birds (Meguini et al. 2018; Boucheikhchoukh et al. 2023) and a limited number of wild species, including the Common Coot (Fulica atra) (Rouag-Ziane et al. 2007), the Greater Flamingo (Phoenicopterus roseus) (Touati and Ectoparasites infesting grebes in northeast Algeria 331 Samraoui 2013), the Glossy Ibis (Plegadis falcinellus) (Touati et al. 2015), the Little Egret (Egretta garzetta) (Temimi et al. 2017), and the White Stork (Ciconia ciconia) in both urban and natural habitats (Bouguessa-Cheriak et al. 2017; Touati et al. 2022). Other studies have addressed parasitic infestations in the Cattle Egret (Bubulcus ibis) (Abdessamed et al. 2018), the Common Moorhen (Gallinula chloropus) (Ziani et al. 2021), the migratory European Turtle Dove (Streptopelia turtur), the exotic Eurasian Collared Dove (Streptopelia decaocto) (Absi et al. 2021), and the Black-headed Gull (Chroicocephalus ridibundus) (Hamdoune et al. 2023). Given the scarcity of research on the parasitic fauna of birds in Algeria, the present study is of significant importance, as it provides an opportunity to identify previously unrecorded species of lice and feather mites affecting the resident avifauna in the eastern regions of the country. This study focuses specifically on two grebe species inhabiting Lake (...truncated)