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A survey was conducted to determine the status of wild mammals and birds as hosts for Amblyomma variegatum (F.) and other tick species in Antigua. Surveys of wild mammals and birds were conducted periodically from September 1988 through May 1991. Wild mammals surveyed included the small Indian mongoose (Herpestes auropunctatus Hodgson), Norway rat (Rattus norvegicus Berkenhout), and house mouse (Mus musculus L.), but only mongooses were surveyed intensively. Larvae and nymphs of A. variegatum, larvae of Boophilus microplus (Canestrini), and larvae of Ornithodoros puertoricensis (Fox) were recovered. The mean prevalences of infestation of mongooses by A. variegatum larvae and nymphs were 4.7 and 1.3%, respectively; maximums were 16.1 and 5.0%, respectively. The mean prevalence of infestation of mongooses by B. microplus was 3.2%. O. puertoricensis is reported from Antigua for the first time. The mean prevalence of infestation of mongooses by O. puertoricensis larvae was 41.2%, but seasonal prevalences ranged from 27.8 to 55.0%. Of 610 birds representing 16 species, three Carib grackles (Quiscalus lugubris Swainson) were each infested with one larva of A. variegatum.

The potential role of cattle egrets, Bubulcus ibis (L.), in the dissemination of Amblyomma variegatum (F.) in the eastern Caribbean was evaluated. The status of cattle egrets as hosts for A. variegatum in Antigua was determined during seven survey periods between September 1988 and May 1991. The mean prevalences of infestation by larvae and nymphs were 2.3 and 0.5%, respectively. The mean intensity and relative density of infestation by larvae were 8.8 (SD = 9.80) and 0.2 (SD = 0.28), respectively. Cattle egrets examined in Guadeloupe during February-March 1991 were not infested but 5.9% were infested by larvae during June-July 1991. Interisland movement of cattle egrets was evaluated relative to emigration of birds captured and marked in Antigua and Guadeloupe. During this aspect of the study, 1,129 cattle egrets were captured, marked, and released. Of 195 sighting reports received, 56 were determined to be independent sightings. Emigration of cattle egrets included movement of birds marked in Antigua or Guadeloupe to 14 Caribbean islands and the Florida Keys. Interisland movement occurred in each of the discrete observation periods during the 3-yr study period. The rate of emigration per period ranged from 1.2 to 12.9%. That cattle egrets served as hosts for immature A. variegatum in the eastern Caribbean and moved between islands in the region demonstrates that these birds could serve as disseminators of the tick. Estimates of the numbers of infested cattle egrets emigrating from Antigua and Guadeloupe ranged from 0 to 0.24% of the current populations.