| Title: |
Testing the assumption of annual shell ring deposition in freshwater mussels |
| Author(s): |
Haag, Wendell R.; Commens-Carson, Amy M. |
| Date: |
2008 |
| Source: |
Can. J. Fish. Aquat. Sci., Vol. 65: 493-508 |
| Description: |
We tested the assumption of annual shell ring deposition by freshwater mussels in three rivers using 17 species. In 2000, we notched shell margins, returned animals to the water, and retrieved them in 2001. In 2003, we measured shells, affixed numbered tags, returned animals, and retrieved them in 2004 and 2005. We validated deposition of a single internal annulus per year in all species and in 94% of specimens. Most unvalidated shells were old individuals with tightly crowded rings. Handling produced a conspicuous disturbance ring in all specimens and often resulted in shell damage. Observed growth was similar to but slightly lower than growth predicted by von Bertalanffy length-at-age models developed independently from shell annuli; further, handling specimens in 2 consecutive years reduced growth more than handling only once. These results show that mussels are extremely sensitive to handling. Brief handling does not likely increase short-term mortality, but repeated handling could decrease long-term fitness. Handling effects should be considered in sampling programs or when interpreting results of mark-recapture studies designed to estimate mussel growth. Production of annual shell rings is a pervasive phenomenon across species, space, and time, and validated shell rings can provide accurate estimates of age and growth. |
![[ PDF Icon ] [ PDF Icon ]](../images/pdficonarrow.gif) |
View and Print this Publication (2.81 MB) |
| Pristine Version |
An uncaptured or "pristine" version of this publication is available. It has not been subjected to OCR (Optical Character Recognition) and therefore does not have any errors in the text. However it is a larger file size and some people may experience long download times. The "pristine" version of this publication is available here:
View and Print the PRISTINE copy of this Publication (2.49 MB)
|
| Publication Notes: |
- We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
- This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.
- Our on-line publications are scanned and captured using Adobe Acrobat. During the capture process some typographical errors may occur. Please contact the SRS Webmaster, srswebmaster@fs.fed.us if you notice any errors which make this publication unuseable.
|
![[ Get Acrobat ]](/images/getacro.gif) |
Get the latest version of the Adobe Acrobat reader or Acrobat Reader for Windows with Search and Accessibility |