Infestation parameters of chewing lice (Phthiraptera: Amblycera and Ischnocera) on bald eagles, Haliaeetus leucocephalus (Accipitriformes: Accipitridae), in Manitoba, Canada

Bald eagles (Haliaeetus leucocephalus (Linnaeus); Accipitriformes: Accipitridae) from 92 locations in Manitoba were examined for chewing lice (Phthiraptera: Amblycera and Ischnocera) from 1992 to 2017. Bald eagles were salvaged from rehabilitation hospitals and were examined using two methods, dry-ruffling (n = 107) and washing (n = 40). We collected 39 066 bald eagle lice of four genera and six species: Colpocephalum flavescens (De Haan), C. napiforme (Rudow), C. turbinatum (Denny) (Phthiraptera: Menoponidae) (total for all Colpocephalum species = 18 082), Craspedorrhynchus halieti (Osborn) (Phthiraptera: Philopteridae) (n = 49), Degeeriella discocephalus (Burmeister) (Phthiraptera: Philopteridae) (n = 20 912), and Kurodaia fulvofasciata (Piaget) (Phthiraptera: Menoponidae) (n = 23). Quantitative data were collected on all genera with the comparison of washed to dry-ruffled. Colpocephalum flavescens and D. discocephalus dominated the louse populations, with similar prevalence and mean intensity. Both genera had sex ratios near 1.0, and similar nymph-to-female ratios near 3:1. The dry-ruffling method was relatively inefficient, collecting 11% as many lice as the washing method. Total prevalence for dry-ruffled birds was 63%; total mean intensity was 103.5, but for washed birds, the prevalence was 93% with a mean intensity of 861.1. No Laemobothrion vulturis (Fabricius) (Phthiraptera: Laemobothriidae) were found.