NATURAL ATTACHMENT DURATION OF NYMPHS OF THE TICK IXODES URIAE (ACARI, IXODIDAE) ON KITTIWAKE RISSA-TRIDACTYLA NESTLINGS

Daily searches of the plumage of 62 kittiwake (Rissa tridactyla) chick s were carried out for 3 weeks to determine the attachment duration of the tick Ixodes uriae. All ticks recorded were nymphs and their mean duration of attachment was 5.2 +/- 1.7 days (n = 93). Seventy-four per cent of the ticks survived to engorgement and were assumed to have fe d successfully. The mean duration of attachment of successful ticks wa s 5.8 +/- 1.0 days (n = 69), significantly longer than that of unsucce ssful ticks (3.3 +/- 2.1 days, n = 24). There was no difference in sur vival rates to engorgement between ticks attached to feathered and unf eathered parts of the body (78.3 and 79.2%, respectively), but the dur ation of attachment of successful ticks was significantly longer on un feathered compared to feathered areas. There were no significant diffe rences in the survival to engorgement or duration of attachment betwee n ticks found on young (c. less than or equal to 11 days) and old (> 1 1 days) kittiwake nestlings. The attachment duration was not related t o the total number of ticks found on the host or the number of ticks p resent in the immediate vicinity of the site of attachment. This work provides important data on the parameter of attachment durations of ny mphal I. uriae on free-living kittiwakes; the data can be used for inc orporation into the application of population modelling.