A system for weighing hihi (stitchbirds) at feeders, recording how long they fed, and measuring the amount of food consumed. The bird is perched on a loadbar which is connected to the digital readout above the bird. The loadbar also weighs the feeder, which becomes lighter as birds remove the sugar solution. In this case, the reading was -18.0 g before this female hopped on the scale, and her weight was 29.0 g. When the bird hops on the perch, she depresses a microswitch which signals a video camera to start recording. This setup was used in on-off food supplementation experiments to what times of year (if any) that birds lost condition without supplementary food. These experiments were done to test habitat suitability after hihi were reintroduced to Mokoia Island (Armstrong & Perrot, Conservation Biology, in press) and Tiritiri Matangi Island. The scales are from Weighing Sytems Ltd (Nelson, N.Z.), and feeders were donated to the project by Perky-Pet Products Co. (Colorado, U.S.A.). Photo by Brent Stephenson.
Reintroduction in New Zealand | Reintroduction Specialist Group, Australasian Section | Doug Armstrong