Researchers have been concerned that relying on voluntary recoveries will bias the recovery data. Paulik (1961) [Abstract] described a table, which gives the total number of tags that must be recovered in order to have a prescribed probability of discovering non-reporting by fishermen of a certain percentage of recaptured tags when a portion of the catch or of the effort is inspected by special observers.
CWT - Adipose fin excision, of coded wire tagged salmonids, have provided a "flag" for tag returns for more than 20 years (Johnson 1990 [Abstract]). This usually involves a reward system or qualification for such in a lottery. As demonstrated with paddlefish (Heinricher and Fiss 1996 [Abstract]), voluntary recovery does not require a flag. In this case, incentives encourage fishers to return distal portions of all paddlefish rostra - the CWT target area - thereby providing more representative data relating to the occurrence of tagged fish.
VI Alpha - Blankenship and Tipping (1993) [Abstract] reported on the voluntary returns of tagged coastal cutthroat trout by anglers.
VIE - Although well suited, there are no known reports of voluntary recovery of VIE tagged specimens.
Contents
