, Volume 271, Issue 2, pp 119–127

Substratum preference of the tropical estuarine crabs, Uca tangeri Eydoux (Ocypodidae) and Ocypode cursor Linne (Ocypodidae)

  • Ita O. Ewa-Oboho


The vertical and horizontal distribution of two burrowing mud crabs, (Ocypodidae) and Ocypode cursor Linne 1758 (Ocypodidae) are described for the Bonny Estuary (7° 00' E: 4° 20′ N), S. Nigeria. Substratum preference is the most prominent factor influencing distribution, but lack of tolerance to low salinities (< 6%o) is also important, and prevents Ocypode cursor from occurring close to freshwater. The two species have slightly different sediment organic content and grade size requirements. Ocypode cursor was concentrated in well drained sandy sediment above mid-tide-level, whilst Uca tangeri was found in water-logged areas slightly above and below Mid-tide-level. This vertical demarcation is attributed to differential feeding and burrowing adaptations related to different substrata, rather than to differential tolerances to desiccation.

Key words

Uca tangeri Ocypode cursor substratum preference Bonny Estuary 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Barrier, R. S. K., 1967. The osmotic behaviour of a number of grapsoid/crabs with respect to their differential penetration of an estuarine system. J. exp. Biol. 47: 535–551.Google Scholar
  2. Beer, C. G., 1959. Notes on the behaviour of two estuarine crab species. Trans. Soc. N.Z. 86: 197–203.Google Scholar
  3. Beukema, J. J. & K. Essink, 1986. Common patterns in the fluctuations of macro-zoo benthic species living at different places on tidal flats in the Wadden sea. Hydrobiologia 142: 199–207.CrossRefGoogle Scholar
  4. Bott, R., 1955. Die Susswasserkrabben von Afrika and ihre Stammesgeschichte. Ann. Mus. Congo belge c(3) 3: 209–352.Google Scholar
  5. Chilton, N. B. & C. M. Bull, 1984. Influence of predation by a crab on distribution of the size-groups of three intertidal gastropods in South Australia. Mar. Biol. 83: 163–169.CrossRefGoogle Scholar
  6. Connell, J. H., 1970. A predator-prey System in the marine intertidal region I. Balanus glandula and several predatory species of Thais. Ecol. Monogr. 40: 50–78.CrossRefGoogle Scholar
  7. Crane, J., 1975. Fiddler crabs of the World (Ocypodidae genus Uca.). Princeton University Press, New Jersy, 736 pp.Google Scholar
  8. Ekweozor, I. K. E., 1985. A baseline survey for monitoring oil pollution in the Bonny Estuary, Nigeria. M. Phil. Thesis Rivers State University of Science & Technology, Harcourt, Nigeria, 217 pp.Google Scholar
  9. Ewa-Oboho, I. O., 1988. Ecological Effects of Crude oil on a Mangrove swamp of the Bonny Estuary. M. Phil. Thesis. Rivers State University of Science & Technology, Port Harcourt, Nigeria, 211 pp.Google Scholar
  10. Fielder, D. R. & M. B. Jones, 1979. Observations of feeding behaviour in two New Zealand mud crabs (Helice crassa, and Macrophthalmas hirtipes). Mauri Ora 6: 41–46.Google Scholar
  11. Hartnoll, R. G., 1973. Factors affecting the distribution and behaviour of the crab Dotilla fenestrata on East African Shores. Estuar. mar. Sci.: 137–152.Google Scholar
  12. Holthuis, I. B., 1981. True crabs In W. Fishcher, G. Rianchi & W. D. Scott (eds), FAO species Identification sheets for Fishery purposes. Eastern central Atlantic; Fishing areas 34, 47.Google Scholar
  13. Herreid, C. F., 1969. Waster loss of crabs from different habitats. Comp. Biochem. Physiol. 28: 829–839.CrossRefGoogle Scholar
  14. Icely, J. D. & A. D. Jones, 1978. Factors affecting the distribution of the genus Uca (Crustacea: Ocypodidae) on East African shores. Estuar. coast. mar. Sci. 6: 315–325.CrossRefGoogle Scholar
  15. Jensen, K., 1986. Changes of the macro-zoobenthos at 3 monitoring stations in the Western Baltic Sea and the Sound. Hydrobiologia 142: 129–135.CrossRefGoogle Scholar
  16. Jones, M. B., 1981. Effect of Temperature, Season and Stage of life cycle on salinity tolerance of the estuarine crab Helice crasca Dana (Grapsidae) J. exp. mar. Biol. 52: 271–282.CrossRefGoogle Scholar
  17. Kinne, O., 1971. Salinity: animals-invertebrates. In O. Kinne, (ed.), Marine Ecology, vol. 1, Environmental factors pt 2. Wiley-Interscience, London: 821–1082.Google Scholar
  18. Macnae, W., 1968. A general account of the fauna and flora of mangrove swamps in the Indo-West Pacific region. Adv. Mar. Biol. 6: 73–270.CrossRefGoogle Scholar
  19. McIntosh, D. J., 1980. Ecology and productivity of Malaysia Mangrove crab population (Decapoda: Brachyura). Proc. Asia Symp. on mangrove environment, Kaula Lumpur: 25–29.Google Scholar
  20. Mclusky, D. S., 1968. Some effects of salinity on the distribution and abundance of corophium volutator in the Y than Estuary. J. mar biol. Ass. U.K. 48: 443–454.CrossRefGoogle Scholar
  21. Manning, R. B., 1982. Archaeus powalli, a new spider crab for Nigeria. (Crustacea; Decapoda, Majidea). J. Crustacean Biology 2: 459–463.CrossRefGoogle Scholar
  22. Manning R. B.& I. B. Holtuis, 1981. West African Brachyurans crabs (Crustacean: Decapoda). Smithsonian Contribution to zoology No. 306: xii + 379 pp.Google Scholar
  23. Monod, T., 1956. Hippidea et Brachyura ouest-africains. Mem. IFA No. 45: 674 pp.Google Scholar
  24. Morgans, J. F. C., 1956. Notes on the analysis of shallow water soft strata. J. anim. Ecol. 367–387.Google Scholar
  25. Ombu, I. E., 1987. The impact of the Okrika Oil Terminal on the crabs of the central Bonny Estuary. Nigeria M. Phil. Thesis. River State University of Science and Technology Port Harcourt.Google Scholar
  26. Paine, R. T., 1974. Inter-tidal community structure: experimental studies on the relationship between a dominant competitor and its principal predator. Oecologia (Berlin) 15: 93–120.CrossRefGoogle Scholar
  27. Powell, C. B., 1983. Key for the identification of NigerianGoogle Scholar
  28. Snedecor, G. W. & W. G. Corhran, 1968. Statistical Methods. The Iowa State University Press, Ames, 593 pp.Google Scholar
  29. Spraque, J. B., 1969. Measurement of pollutant toxity to fish. I. Bioassay methods for acute toxity. Wat. Res. 3: 793–821.CrossRefGoogle Scholar
  30. Warner, G. F., 1969. Occurrence and Distribution of Crabs in a Jamaican mangrove swamps. J. anim. Ecol. 38: 379–387.CrossRefGoogle Scholar
  31. Winston, P. W. & D. H. Bates, 1960. Staturated solutions for the control of humidity in biological research. Ecology 41: 232–237.CrossRefGoogle Scholar
  32. Young, A. M., 1978. Desiccation tolerances for three hermit crab species Clibanarius vittatus (BOSC), Pagurus pollicaris say and P. iongicarpus Say (Decapoda, Anomura) in the North in let Estuary, South Carrolina, USA. Estuar. Coast. mar. Sci. 6: 117–122.CrossRefGoogle Scholar

Copyright information

© Kluwer Academic Publishers 1993

Authors and Affiliations

  • Ita O. Ewa-Oboho
    • 1
  1. 1.Institute of OceanographyUniversity of CalabarCalabarNigeria

Personalised recommendations