For fisheries research the lengths and weights of fishes are important data elements used to characterize biological dynamics; however, in order to collect accurate lengths and weights there can be stress and mortality issues due to handling methods. In particular, during coastal and oceanic longline projects, collecting accurate biological data from large animals is often problematic due to associated landing and handling difficulties. To improve the accuracy of biological data collected from large specimens and decrease survey-induced stress and mortalities during longline surveys, a portable landing sling was designed for use with shipboard hydraulic cranes. The landing sling enables researchers to improve biological data quality through increased opportunities to collect accurate lengths and weights, take detailed photographs, and conduct non-invasive biological sampling with minimal physical damage to large fishes captured. Thus, using a landing sling allows researchers to collect essential biological data while being responsibly conservative. (C) 2007 Published by Elsevier B.V.