PIT and VIE Tagging Effects on a Small-Bodied Fish (Cyprinodon tularosa)

Authors: Peterson, Damon*, Trantham, Tulley, Simpson, Randi, Caldwell, Colleen C.

Year: 2015 (xlvii)

Abstract

Body size has commonly been used as the primary predictor of suitable candidates for individual tagging; however few studies have focused on the impacts of tagging on small bodied adult fish. To address the hypothesis that body size predicts the probability of survival among tagged, small-bodied fish we quantified survival, tag retention, and growth in a southwestern pupfish (Cyprinodon tularosa). We used two tagging methods: (1) 8.5-mm PIT tags and (2) VIE and calculated tagging related mortality, tag retention, and growth over a 75d period for four different size classes (TL): 15-29mm/0.1-0.6g, 30-39mm/0.4-1.2g, 40-49mm/1.0-2.2g, and 50-59mm/2.3-4.2g. Fish mass was a good predicator of the probability of survival across all PIT-tagged animals (P=0.016) where animals were 62 times more likely to survive tagging as mass increased by 1 gram. The smallest size class (15-29mm TL) experienced the greatest rate of mortality (72%). VIE related mortality was marginally significantly different from the control group (P=0.076). The growth rate of all tagged animals was similar to the control group. Our data indicated that White Sands pupfish can be effectively tagged using 8-mm PIT tags with minimal tag loss or mortality at sizes ¡Á37mm.