Age and growth in the Australian freshwater mussel, Westralunio carteri , with an evaluation of the fluorochrome calcein for validating the assumption of annulus formation

  • Authors: Klunzinger, Michael W.; Beatty, Stephen J.; Morgan, David L.; Lymbery, Alan J.; Haag, Wendell R.
  • Publication Year: 2014
  • Publication Series: Scientific Journal (JRNL)
  • Source: Freshwater Science 33(4) 1127-1135
  • DOI: 10.1086/677815

Abstract

Growth and longevity of freshwater mussels (Unionida) are important for defining life-history strategies and assessing vulnerability to human impacts. We used mark–recapture and analysis of shell rings to investigate age and growth of the hyriid, Westralunio carteri, at 5 sites in southwestern Australia. We tested the utility of the in situ marker calcein for validating the assumption of annulus formation in adults. Calcein was incorporated into the shells of all recovered individuals, but it provided an interpretable reference mark in only 4 of 16 individuals. These 4 individuals produced 1 shell ring subsequent to the mark, supporting the assumption of annulus production during the austral winter. Maximum age ranged among populations from 36 to 52 y and maximum size ranged from 72.9 to 82.8 mm. Mean age and length did not differ between sexes, and growth trajectories differed between sexes at only 1 site. Estimates of growth measured by the von Bertalanffy growth constant, K, ranged from 0.021 to 0.336 among sites. Estimates from mark–recapture experiments were 20 to 52% lower than values from shell annuli at all sites except 1 where K from shell annuli was ∼½ that estimated from mark–recapture. Both methods showed a positive relationship between K and mean water temperature among sites, suggesting a role of riparian shading in regulating stream temperature, and hence, indirectly influencing mussel growth. Mussel growth and mean N or P concentrations were not related among sites, but total N at the site with highest mussel growth was >2× higher than at any other site. Westralunio carteri is a long-lived, slow-growing bivalve. Maximum age, K, and probable age at maturity (4–6 y) are similar to other slow-growing freshwater bivalve groups. This suite of life-history traits is considered an adaptation for stable aquatic habitats. Therefore, W. carteri can be expected to adapt poorly to human impacts, such as riparian clearing and water extraction, which increase the temporal variability of environmental conditions in streams.

  • Citation: Klunzinger, Michael W.; Beatty, Stephen J.; Morgan, David L.; Lymbery, Alan J.; Haag, Wendell R. 2014. Age and growth in the Australian freshwater mussel, Westralunio carteri , with an evaluation of the fluorochrome calcein for validating the assumption of annulus formation . Freshwater Science. 33(4): 1127-1135. 9 p. DOI: 10.1086/677815
  • Keywords: life history, growth rate, von Bertalanffy, Hyriidae, Unionoida, Unionida, Australia
  • Posted Date: October 14, 2015
  • Modified Date: October 20, 2015
  • Print Publications Are No Longer Available

    In an ongoing effort to be fiscally responsible, the Southern Research Station (SRS) will no longer produce and distribute hard copies of our publications. Many SRS publications are available at cost via the Government Printing Office (GPO). Electronic versions of publications may be downloaded, printed, and distributed.

    Publication Notes

    • This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.
    • Our online publications are scanned and captured using Adobe Acrobat. During the capture process some typographical errors may occur. Please contact the SRS webmaster if you notice any errors which make this publication unusable.
    • To view this article, download the latest version of Adobe Acrobat Reader.