We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
Occurrence, Size, and Tag Retention of Sneaker Male Hatchery Rainbow Trout.
- Authors
Isely, J. Jeffery; Grabowski, Timothy B.
- Abstract
One alternative reproductive tactic involving early-maturing, cryptic males is referred to as "sneaking." Although sneakers tend to be easily detectable upon close inspection, little is known about the proportion of a fish population consisting of sneakers. We examined 15,400 age-1 rainbow trout Oncorhynchus mykiss in a hatchery. Total length (mm), wet weight (g), and sex (sneaker male or unknown) were recorded for each fish. We also individually tagged each sneaker male with soft visual implant alphanumeric (VIalpha) tags that were sequentially numbered and held the fish for 25 d before inspection. Sneakers constituted 2.8% of the hatchery rainbow trout population and were smaller in total length and weight than typical rainbow trout of the same age. Retention of the VIalpha tags in sneakers was 58.9%, significantly lower than has been reported under similar circumstances. We found that sneaker males may contribute substantially to hatchery populations. Reduced tag retention in sneakers may bias studies evaluating the effect of hatchery fish on wild populations. We believe that hatchery-produced sneaker males have the potential to contribute importantly to the genetic composition of wild populations.
- Subjects
RAINBOW trout; HATCHERY fishes; RAINBOW trout fishing; FISH hatcheries; FISH populations
- Publication
North American Journal of Aquaculture, 2004, Vol 66, Issue 3, p234
- ISSN
1522-2055
- Publication type
Article
- DOI
10.1577/A03-023.1