Oecologia

, Volume 53, Issue 2, pp 146–151 | Cite as

Size specific predation by herons and its effect on the sex-ratio of natural populations of the mosquito fish Gambusia affinis baird and girard

  • Robert H. Britton
  • Michael E. Moser
Article

Summary

Sex-ratios of Gambusia affinis populations in freshwater marshes in the Camargue (Rhône Delta), are highly biased in favour of males, whereas the sex-ratios in ditches are close to unity. Studies of the diet of free living birds and experimental studies on prey size selection in captivity show that the abnormal sex-ratios in marshes can be attributed to differential heron predation. Ditches are relatively free from predation. Mature female Gambusia are larger, and have an energy content 5–25 times greater than that of mature males. Handling times of Grey Heron (Ardea cinerea) and Little Egret (Egretta garzetta) are only slightly longer for female Gambusia than males. Hence, females represent a much more profitable prey.

Analysis of nestling regurgitates show that Gambusia makes up a considerable proportion of the diet of four species of Camargue herons, and that the majority of Gambusia taken are females. Under experimental conditions, captive herons consume almost exclusively female fish, even when offered in ratios where they are heavily outnumbered by males.

The relevance of these results to optimal diet theory is discussed.

Keywords

Mature Male Mature Female Prey Size Handling Time Size Selection 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. Aguesse P, Marazanof F (1965) Les modifications des milieux aquatiques de Camargue au cours des 30 dernières années. Annales de Limnologie 1:163–190Google Scholar
  2. Bacon EJ, Neill WH, Kilambi RV (1968) Temperature selection and heat resistance of the mosquito fish, Gambusia affinis. Proc 21st Ann Conf Southeastern Ass Game Fish Comm (1967) 411–416Google Scholar
  3. Barney RL, Anson BJ (1921) Seasonal abundance of the mosquito destroying top-minnow, Gambusia affinis, especially in relation to male frequency. Ecology 2:53–69Google Scholar
  4. Berglund A (1981) Sex dimorphism and skewed sex-ratios in the prawn species Palaemon adspersus and P. squilla. Oikos 36:158–162Google Scholar
  5. Borowsky RL (1973) Social control of adult size in males of Xiphophorus variatus. Nature 245:332Google Scholar
  6. Britton RH, Podlejski VP (1981) Inventory and classification of the wetlands of the Camargue (France). Aquat Bot 10:195–228Google Scholar
  7. Campbell H, Martin DK, Ferkovitch PE, Harris BK (1973) Effects of hunting and some other environmental factors on Scaled Quail in New Mexico. J Wildl Management 20:93–94Google Scholar
  8. Carlson DR (1969) Female sexual receptivity in Gambusia affinis (Baird & Girard). Texas J Sci 21:167–173Google Scholar
  9. Charnov EL (1976) Optimal foraging: attack strategy of a mantid. Amer Natur 110:141–151Google Scholar
  10. Crivelli AJ (1981) Les peuplements de poissons de la Camarque. Revue d'Ecologie (Terre et Vie) 35:617–671Google Scholar
  11. Emlen ST, Oring LW (1977) Ecology, sexual selection and the evolution of mating systems. Science 197:215–223Google Scholar
  12. Farr JA (1975) The role of predation in the evolution of social behaviour of natural populations of the guppy, Poecilia reticulata (Peters) (Pisces: Poeciliidae). Evolution 29:151–158Google Scholar
  13. Goss-Custard JD (1977) Predator responses and prey mortality in the Redshank Tringa totanus (L.) and a preferred prey Corophium volutator (Pallas). J Anim Ecol 46:1–36Google Scholar
  14. Haas R (1976) Sexual selection in Notobranchius guentheri (Pisces: Cyprinodontidae). Evolution 30:614–622Google Scholar
  15. Hafner H (1977) Contribution à l'étude écologique de quatre éspéces de hérons (Egretta garzetta L., Ardeola ralloides Scop., Ardeola ibis L., Nycticorax nycticorax L.) pendant leur nidification en Camargue. Thèse Univ Toulouse 183 ppGoogle Scholar
  16. Haskins CP, Haskins EF, McLaughlin JJA, Hewitt RE (1961) Polymorphism and population structure in Lebistes reticulatus, an ecological study. In: Vertebrate Speciation (ed) Blair WF, Univ Texas PressGoogle Scholar
  17. Ivlev VS (1961) Experimental ecology of the feeding of fishes. Yale Univ Press 302 ppGoogle Scholar
  18. Johansen PH, Cross JA (1980) Effects of sexual maturation and sex steroid hormone treatment on the temperature preference of the guppy Poecilia reticulata (Peters). Can J Zool 58:586–588Google Scholar
  19. Kallman KD, Schreibman MP, Borkoski V (1973) Genetic control of gonadotrop differentiation in the platyfish, Xiphophorus maculatus (Poeciliidae). Science 181:678–680Google Scholar
  20. Krumholz LA (1948) Reproduction in the western mosquito-fish Gambusia affinis (Baird & Girard), and its use in mosquito control. Ecol Monogr 18:1–43Google Scholar
  21. Krumholz L (1963) Relationships between fertility, sex ratio, and exposure to predation in populations of the mosquito fish Gambusia manni Hubbs at Bimini, Bahamas. Int Rev ges Hydrobiol 48:201–256Google Scholar
  22. MacArthur RH, Pianka ER (1966) On the optimal use of a patchy environment. Amer Natur 100:603–609Google Scholar
  23. Orians GH, Pearson NE (1979) On the theory of Central Place Foraging. In: The Analysis of Ecological Systems (eds) Horn DJ, Mitchell RD, Stairs GR, Ohio State Univ Press, Columbus pp 155–157Google Scholar
  24. Peden AE (1973) Variation in anal spot expression in gambusiin females and its effect on male courtship. Copeia 1973:250–263Google Scholar
  25. Phillipson J (1964) A miniature bomb calorimeter for small biological samples. Oikos 15:130–139Google Scholar
  26. Reuterwall C (1981) Temporal and spatial variability of the calf sex ratio in Scandinavian moose Alces alces. Oikos 37:39–45Google Scholar
  27. Seghers BH (1973) An analysis of geographic variation in the antipredator adaptions of the guppy, Poecilia reticulata. Thesis Univ British ColumbiaGoogle Scholar
  28. Sohn JJ (1977a) Socially induced inhibition of genetically determined maturation in the platyfish, Xiphophorus maculatus. Science 195:199–201Google Scholar
  29. Sohn JJ (1977b) The consequences of predation and competition upon the demography of Gambusia manni (Pisces: Poeciliidae). Copeia 1977:224–227Google Scholar
  30. Snelson, FF, Wetherington JD (1980) Sex ratio in the sailfin molly, Poecilia latipinna. Evolution 34:308–319Google Scholar
  31. Tamisier A (1974) Etlio-ecological studies of Teal wintering in the Camargue (Rhone Delta, France). Wildfowl 25:123–133Google Scholar
  32. Tinbergen LM (1981) Foraging decisions in starlings (Sturnus vulgaris L.). Ardea 69:1–67Google Scholar

Copyright information

© Springer-Verlag 1982

Authors and Affiliations

  • Robert H. Britton
    • 1
  • Michael E. Moser
    • 1
    • 2
  1. 1.Station Biologique de la Tour du ValatArlesFrance
  2. 2.Department of ZoologyUniversity of DurhamDurhamUK

Personalised recommendations