Measuring Leg Thrust Forces in the Common Starling

We describe the design of a force-transducing perch which measures the reaction forces of small birds taking off and landing. In common starlings, landing forces are lower than take-off forces, because the bird may decelerate prior to landing by using its wings. Both landing and take-off forces are significantly correlated with body mass; however, the angles of these reaction forces show no significant mass-dependence and are not repeatable within individuals. Diversity in take-off or landing strategy could be advantageous in confusing predators.