Get access

Morphological differentiation in introduced pumpkinseed Lepomis gibbosus (L.) occupying different habitat zones in Portuguese reservoirs

Authors

  • Y. Bhagat,

    Corresponding author
    1. * Watershed Ecosystems Graduate Program, Trent University, Peterborough, Ontario, K9J 7B8 Canada, Environmental & Resource Studies Program and Department of Biology, Trent University, Peterborough, Ontario, K9J 7B8 Canada and § Departamento de Engenharia Florestal, Instituto Superior de Agronomia, Tapada da Ajuda, 1349-017 Lisboa, Portugal
    Search for more papers by this author
  • M. G. Fox,

    1. * Watershed Ecosystems Graduate Program, Trent University, Peterborough, Ontario, K9J 7B8 Canada, Environmental & Resource Studies Program and Department of Biology, Trent University, Peterborough, Ontario, K9J 7B8 Canada and § Departamento de Engenharia Florestal, Instituto Superior de Agronomia, Tapada da Ajuda, 1349-017 Lisboa, Portugal
    Search for more papers by this author
  • M. T. Ferreira

    1. * Watershed Ecosystems Graduate Program, Trent University, Peterborough, Ontario, K9J 7B8 Canada, Environmental & Resource Studies Program and Department of Biology, Trent University, Peterborough, Ontario, K9J 7B8 Canada and § Departamento de Engenharia Florestal, Instituto Superior de Agronomia, Tapada da Ajuda, 1349-017 Lisboa, Portugal
    Search for more papers by this author

†Tel.: +1 705 748 1011 ext. 5341; fax: +1 705 748 1026; email: yakutabhagat@trentu.ca

Abstract

Introduced pumpkinseed Lepomis gibbosus sampled from four habitat zones (fluvial pelagic, fluvial littoral, lacustrine pelagic and lacustrine littoral) in three Portuguese reservoirs were used to test the hypotheses that habitats with the least similar characteristics will show the most differentiation, and that morphological differences will relate to functional adaptations to flow and trophic habitats. Results from discriminant function analysis and ANCOVA showed that there were significant differences in external morphology in pumpkinseed captured from the four habitat zones in all three reservoirs. Littoral and pelagic differentiation was stronger than fluvial and lacustrine differentiation in all of the reservoirs, and the most significant variable that differentiated pumpkinseed from the littoral and pelagic habitats was body depth. The illustration of external morphological differentiation in pumpkinseed along both habitat dimensions demonstrates the high degree of morphological plasticity of this introduced species.

Ancillary