Mortality and Growth of Crayfish Internally Tagged with PIT Tags

Abstract Advances in PIT technology have resulted in its increased use to answer ecological questions related to small-bodied organisms. Crayfish are increasingly the subject of such study, and information is needed to guide researchers in determining appropriate uses of the technology for various applications. We internally tagged woodland crayfish Orconectes hylas with either 8.5 mm or 12.5 mm PIT tags and evaluated mortality and growth in the laboratory over 55 d. A logistic model showed that the probability of mortality drops below 20% for crayfish tagged with 8.5-mm or 12.5-mm tags when carapace length (CL) was greater than 23 mm and 26 mm, respectively. There was a positive relation between CL and growth, a difference between growth in males and females, and no statistical difference in growth among treatment types (8.5-mm tag, 12.5-mm tag, controls). Internal implantation of PIT tags into appropriately sized crayfish represents a viable tagging option for many crayfish research applications. Receiv...