Access

You are not currently logged in.

Access your personal account or get JSTOR access through your library or other institution:

login

Log in to your personal account or through your institution.

Influence of Temperature and Food Availability on the Ecological Energetics of the Giant Scallop Placopecten magellanicus. IV. Reproductive Effort, Value and Cost

B. A. MacDonald, R. J. Thompson and B. L. Bayne
Oecologia
Vol. 72, No. 4 (1987), pp. 550-556
Published by: Springer in cooperation with International Association for Ecology
Stable URL: http://www.jstor.org/stable/4218306
Page Count: 7
  • Download ($43.95)
  • Cite this Item
Influence of Temperature and Food Availability on the Ecological Energetics of the Giant Scallop Placopecten magellanicus. IV. Reproductive Effort, Value and Cost
Preview not available

Abstract

Gonad output, reproductive effort and residual reproductive value are greater in scallops (Placopecten magellanicus) from shallow water, where conditions are more favourable, than in scallops from deep water. Variation between years in these fitness correlates is also greater in shallow water scallops. High reproductive effort is associated with a greater reproductive cost, although in general reproduction in this species appears to be "restrained", and only in older individuals from shallow water is there evidence of "reckless" reproductive behaviour. Reproductive effort increases as the animal grows older, but residual reproductive value is a maximum at age 4 years, after which it decreases with age owing to greater mortality. Localities vary in their suitability for scallop growth and reproduction, and at one Newfoundland site conditions in shallow water (10 m) are better than those in deep water (31 m). Scallops from the former have a greater fitness than those from the latter. The energy costs of reproduction have implications for life history variability in P. magellanicus, although for a considerable part of its lifetime the scallop is able to maximise gamete production in response to environmental factors (especially the food supply) without trading off reproduction against growth or maintenance.

Page Thumbnails

  • Thumbnail: Page 
[550]
    [550]
  • Thumbnail: Page 
551
    551
  • Thumbnail: Page 
552
    552
  • Thumbnail: Page 
553
    553
  • Thumbnail: Page 
554
    554
  • Thumbnail: Page 
555
    555
  • Thumbnail: Page 
556
    556