Resource Ecology & Fisheries Management (REFM) Division
Age & Growth Program
Estimated production figures for the period
from 1 January through 31 March 2009.
Total production figures were 6,386,
with 1,586 test ages and 80 examined
and determined to be unageable. |
Species |
Specimens
Aged |
Flathead sole |
470 |
Rex sole |
993 |
Northern rock sole |
263 |
Yellowfin sole |
477 |
Greenland turbot |
240 |
Pacific cod |
573 |
Walleye pollock |
1,797 |
Pacific ocean perch |
341 |
Northern rockfish |
847 |
Dusky rockfish |
293 |
Quillback rockfish |
52 |
Bigmouth sculpin |
40 |
|
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New and Improved Age Reading Demonstration (ARD) Web Site
The Age and Growth Program has updated its Age Reading Demonstration (ARD) interactive Web site to include many new features. As with the original version, visitors are able to place annulus marks on otolith images and then automatically mark the otolith image with marks from an experienced age reader.
The new version takes advantage of the graphical interactivity of Adobe Flash and allows users to zoom in and out of images, drag a movable scale bar around the image, view ageing statistics, and navigate through image thumbnails. ARD presents otoliths from various species and of varying levels of ageing difficulty, which demonstrates that otoliths from different species often require completely different ageing strategies, and that otoliths from even an easy species can present difficult challenges.
The purpose of the ARD Web site is not to "teach" age reading. An age reader typically must view thousands of otoliths through a binocular microscope in order to understand growth patterns before acquiring proficiency on a species. Instead, the purpose of the ARD Web site is to give scientists and the general public a better appreciation of how difficult age reading really is.
A future goal will be to allow the comparison of ageing criteria, between labs, on a real-time basis using similar software. The ARD Web site can be viewed at: http://www.afsc.noaa.gov/refm/age/interactive.htm.
By Jon Short
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