New Michigan tick (Acari : Ixodidae) and flea (Siphonaptera : Ceratophyllidae) records from colonial nesting birds

Banding and censusing large numbers of gull chicks over a 30-year period on Great Lakes islands has produced a collection of five individual ticks fro m two Herring Gull (Larus argentatus) chicks. The tick species, Hemaphysali s leporispalustris, found on the gulls is commonly found on Snowshoe Hares (Lepus americanus). Although this represents an apparently uncommon record on Herring Gulls, this host could be an important source of aerial vector d ispersal during regular cyclic hare/tick population peaks. Populations of t he flea, Ceratophyllus lari, have increased rapidly in ground nesting Doubl e-crested Cormorant (Phalacrocorax auritus) colonies from none 16 years ago . The possibilities of disease transmission by both of these hematophagus e ctoparasites are assessed with evidence from the literature. The tick and f lea distributions reported here are new host records, and the flea is a new species record for Michigan.