Quick Search:

uzh logo
Browse by:

Zurich Open Repository and Archive

Maintenance: Tuesday, July the 26th 2016, 07:00-10:00

ZORA's new graphical user interface will be relaunched (For further infos watch out slideshow ZORA: Neues Look & Feel). There will be short interrupts on ZORA Service between 07:00am and 10:00 am. Please be patient.

Permanent URL to this publication: http://dx.doi.org/10.5167/uzh-548

Anholt, B R; Vorburger, C; Knaus, P (2001). Mark–recapture estimates of daily survival rates of two damselflies (Coenagrion puella and Ischnura elegans). Canadian Journal of Zoology, 79(5):895-899.

Published Version
View at publisher


Male-biased operational sex ratios are very common in sexually mature dragonflies. These may be due to differential survival or differences in time spent at the breeding site by the sexes. Because most studies are carried out at the breeding site, these two processes can be measured as survival rates or recapture rates using modern capture–mark–recapture methods. We marked 66 female and 233 male Coenagrion puella, and 137 female and 347 male Ischnura elegans during three capture periods spread over 18 days. Each time an animal was recaptured it was re-marked so that the capture history of any captured animal could be readily identified. We recaptured 131 C. puella and 55 I. elegans at least once. We used the Cormack–Jolly–Seber model to estimate the daily probability of survival and recapture. The probability of recapture was, on average, more than three times higher for male C. puella (0.489) than females (0.133) with significant day to day variation. The daily probability of survival did not differ significantly between the sexes (0.860), with no significant variation among days. In contrast, in I. elegans the probability of recapture did not differ between the sexes (0.139 for the first 5 days; between 0.032 and 0.287 for the final 3 days), but the daily probability of surviving was much higher for males (0.812) than for females (0.579). Assuming that the sex ratio was unity at sexual maturity, the recapture and survival rates predicted well the sex ratio of the sample of C. puella but predicted more males than were observed in the sample of I. elegans. This suggests that male I. elegans may suffer higher mortality than females in the immature stage.


23 citations in Web of Science®
27 citations in Scopus®
Google Scholar™



148 downloads since deposited on 11 Feb 2008
11 downloads since 12 months

Detailed statistics

Additional indexing

Item Type:Journal Article, refereed, original work
Communities & Collections:07 Faculty of Science > Institute of Evolutionary Biology and Environmental Studies
Dewey Decimal Classification:570 Life sciences; biology
590 Animals (Zoology)
Date:May 2001
Deposited On:11 Feb 2008 12:16
Last Modified:05 Apr 2016 12:14
Publisher:National Research Council Canada
Publisher DOI:10.1139/cjz-79-5-895

Users (please log in): suggest update or correction for this item

Repository Staff Only: item control page