Odonatologica , Volume 38 - Issue 2 p. 179- 202
(17312) FORBES, M.R.L., 1991. Ectoparasites and mating success of male Enallagma ebrium daraselflies (Odonata: Coenagrionidae). Oikos 60(3): 336-342. — (Dept Biol., Carleton Univ., Colonel By Dr., Ottawa, ON, K1S 5B6, CA). Several researchers have found inverse relationships between mating success of d d and degree of parasitism. Whether such mating biases result from 9 choice of parasite-resistant d d as mates, or from parasite-mediated reductions in d competitiveness for access to 9 9, has stimulated considerable discussion. Here it was found that single d E. ebrium were significantly and consistently parasitized by more larval water mites (Arrenurus spp. and Limnochares americana) than were d d caught either in tandem or copula with 9 9. In contrast, d size was inconsistently related to short-term mating success, although there was a consistent negative correlation between d size and mite numbers which was statistically significant on 2 of 7 sampling days. The existence of such natural covariation and its possible effect on d mating success has not been widely discussed. Lastly, it was found that heavilyparasitized d d responded less often to the presence of d models, and took significantly more foraging trips, than did lightly-parasitized d d. Short-term mating biases with respect to ectoparasitism for E. ebrium d d appears to result from reductions in competitiveness of heavily-parasitized d d, for access to 9 9. Furthermore, the results strongly suggest that apparent reductions in competitiveness reflect decisions by heavily-parasitized d d to pursue mating tactics which are energetically inexpensive. (17313) HAYES, L.M., 1991. Behaviour of New Zealand kingfishers feeding chicks. Notornis 38; 73-79. — (Author’s current address unknown). The behaviour of kingfishers, Halcyon sancta vagans, was studied at 3 nests in Canterbury, New Zealand. Odon. are listed among food items given to chicks.
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