Qualitative Observations of Successful Spawning by Two Species of Small-Bodied Minnows Following PIT Tagging

Abstract

PIT tags are a common tool used to identify and track movements of fishes. Although technological advances facilitated the use of PIT tags across a wide range of fish body sizes, we do not yet fully understand the effects of PIT tagging on basic aspects of many species' life histories (e.g., survival, spawning success, or reproductive output). We observed 2 small-bodied fishes, Red Shiner (Cyprinella lutrensis) and Bluntnose Minnow (Pimephales notatus), achieve successful spawns after PIT tagging. Age-0 fish of both species were observed in multiple experimental stream units during an outdoor mesocosm study in which only PIT-tagged fish were stocked. Although these observations suggest that qualitative effects on spawning success of PIT-tagged, small-bodied fish might be negligible, more quantitative studies need to be conducted to test these assumptions. As use of PIT-tagging technology continues to increase, understanding the effects of PIT tags on fish life histories will ensure that tagging studies provide reliable data without negatively impacting fish populations.