Ectoparasite abundance and apparent absence of hemoparasites in two albatross species in Sub-Antarctic Chile

The Black-browed Albatross (BBA, Thalas- sarche melanophrys) and the Grey-headed Albatross (GHA, Thalassarche chrysostoma) are long-lived sym- patric species breeding in the Atlantic and Pacific sections of the Southern Ocean. While the Atlantic populations of these two species have been the subject of several studies, little information is available on the most important colo- nies in the Southeast Pacific Ocean (Chile). The presence of parasites in these long-lived hosts has been described for the colonies in the Southern Atlantic, but not in those from Chile. Therefore, the objective of this study was to identify ectoparasites and hemoparasites associated with both spe- ciesbreedingintheDiegoRam ́ırezArchipelago(56°S)in Southern Chile. Chicks were examined for ectoparasites during the breeding seasons in 2010 and 2011 (GHA, n = 80; BBA, n = 40). Parasites were collected manually, mounted, and identified to species level. The sex and developmental stage of adult ectoparasites were also determined. Ectoparasites were detected on 78.75 and 32.50% of GHA and BBA chicks, respectively. A total of 126 ectoparasites were obtained: 103 Ixodes uriae ticks (GHA 79.62%, BBA 20.38%); 22 Parapsyllus longicornis Austromenopon affine louse (found on GHA). Diego Ram ́ırez represents a new record and distribution range for I. uriae and A. affine. The presence of hemoparasites was explored on blood smears for GHA (n = 26) and BBA (n = 119), but none were recorded in either of these albatrosses. Keywords Hemoparasite ? Flea ? Louse ? Seabird ? Southern Ocean ? Tick Introduction The Black-browed Albatross (Thalassarche melanophrys, BBA) and Grey-headed Albatross (Thalassarche chrysos- toma, GHA) are long-lived seabirds distributed in the waters of the Southern Hemisphere. Almost the entire global population of BBA (*99%) and the greater portion of GHA numbers (*85%) reside in islands located in the SW Atlantic and SE Pacific regions of the Southern Ocean (Robertson et al. 2007). The Diego Ram ́ırez Archipelago supports the largest numbers of BBA and almost the entire population of GHA in Chile, carrying *20 and *23% of global numbers, respectively (Robertson et al. 2007). BBA is the more abundant albatross species in the archipelago, with GHA breeding around the margins of BBA colonies or in separated groups (Robertson et al. 2007). In Diego Ram ́ırez, these two species have nesting densities of 0.01 and 0.60 nests m-2, respectively (Suazo unpubl. data). During the breeding season, BBA and GHA arrive in late August and early September, respectively, and leave in April (BBA) and in the first half of May (GHA), entering their nonbreeding seasons (Suazo unpubl. data). Diego Ram ́ırezisthemostrepresentativebreedingareaforboth
fleas (GHA = 31.8%, BBA = 68.2%); and a single Austromenopon affine louse (found on GHA). Diego Ram ́ırez represents a new record and distribution range for I. uriae and A. affine. The presence of hemoparasites was explored on blood smears for GHA (n = 26) and BBA (n = 119), but none were recorded in either of these albatrosses.