Tuck et al. (2003) describe an exact time of release and recapture stock assessment model and applied it to the stock of Patagonian Toothfish, Dissostichus eleginoides,at Macquarie Island that have been fished by Australian trawlers from November 1994. This work was previously presented to the Working Group on Fish Stock assessment in 2000 (Tuck et al. 2000; CAMLR-XIX, 2000 paragraphs 3.126, 3.127). The maximum likelihood estimation for this model has more recently been implemented in the AD Model Builder software by Dr Tuck. The AD Model Builder executable that implements Tuck et al. (2003) in order to estimate fish stocks where appropriate mark-recapture and catch data are available has kindly been made available to the Working Group by Dr Tuck. This paper describes the required inputs and the derived outputs for this implementation.