Dispersal characteristics of seven odonate species in an agricultural landscape
1999
Conrad, K.F. | Willson, K.H. | Harvey, I.F. | Thomas, C.J. | Sherratt, T.N.
Dispersal is an ecological phenomenon which is of fundamental importance to population biology. While dispersal behaviour of many orders of winged insects has received a great deal of attention, the dispersal characteristics of odonates have been poorly documented. We used capture‐mark‐recapture techniques to study dispersal behaviour of seven species of odonates breeding on a network of 11 small ponds in Cheshire, U.K. The ponds ranged in size from 615 to 1300 m²‐ and varied from 30 to 860 m apart. We found surprisingly high rates of dispersal between ponds, with 10-47% per species of recaptured individuals moving from their natal pond. The mean probability of dispersal differed significantly among species but the relationship between the probability of dispersal and distance moved consistently followed a simple negative exponential curve for all species. Most individuals stayed at their natal pond, but a few moved long distances. Neither the age at which an individual was marked (teneral vs sexually mature) nor its sex significantly affected its tendency to disperse. The negative exponential relationship suggests that dispersal should be relatively easy to incorporate in more complex models of odonate spatio‐temporal dynamics. To our knowledge, this is the first large‐scale, multi‐species study to assess dispersal behaviour of odonates by direct observation.
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