FACTORS AFFECTING TIMING OF BROOD DESERTION BY FEMALE KENTISH PLOVERSCHARADRIUS-ALEXANDRINUS

We investigated the factors affecting timing of female desertion in th e Kentish plover Charadrius alexandrinus, in relation to a number of p reviously proposed hypotheses. Females deserted their broods on averag e 5.9+/-1.4 (SE) days after hatching. Although timing of desertion was highly variable (0-30d), females deserted on the day of hatching in 9 out of 33 broods (median = 2.3 d). Timing of desertion was not relate d to mass or condition of the female at hatching, suggesting that ener getic costs of incubation were not involved in determining desertion t ime. Similarly, there was no significant relationship between timing o f desertion and the quality of the female's mate, either in terms of h is mass, condition, or relative contribution to parental care prior to desertion. Desertion time was also unrelated to brood quality measure d by weight, size or number of chicks at hatching. However, timing of desertion was negatively related to hatching date. We conclude that th e strategy of desertion is time-constrained: females with early-hatchi ng broods can afford to spend more time with their first brood (perhap s enhancing their expected gain from this brood) and still have suffic ient time to desert, remate and rear a second brood. Females with late r-hatching broods must desert this brood earlier in order to have time to rear a second brood successfully.