Marine Biology

, Volume 58, Issue 2, pp 105–109

Age determination of the soft-shell clam Mya arenaria using shell internal growth lines

  • B. A. MacDonald
  • M. L. H. Thomas
Article

DOI: 10.1007/BF00396121

Cite this article as:
MacDonald, B.A. & Thomas, M.L.H. Mar. Biol. (1980) 58: 105. doi:10.1007/BF00396121

Abstract

Shells of known-age Mya arenaria have revealed an internal annual growth pattern in this bivalve. The number of external growth rings on the shell exterior does not correspond to the age of the clams. This study provides an alternative method to using external annual rings for age determination. The internal growth lines are visible in thin sections when the shells are cut from the umbo to the ventral margin. The lines are formed by late spring of each year prior to spawning and are probably in response to decreased winter growth. When the 7 year olds were examined it was difficult to distinguish the most recent growth line and the inner shell layer. This could result in ages being underestimated. This annual pattern of internal growth lines could be useful to biologists and paleoecologists engaged in population studies.

Copyright information

© Springer-Verlag 1980

Authors and Affiliations

  • B. A. MacDonald
    • 1
  • M. L. H. Thomas
    • 1
  1. 1.Department of BiologyUniversity of New BrunswickSaint JohnCanada