The premature failure of a batch of radio transmitters in 2010 was a major headache for the kākāpō programme; a total of 26 transmitters failed, making it impossible to monitor the day to day whereabouts and survival of 21% of the kākāpō population.
If a female kākāpō doesn’t have a working transmitter it’s virtually impossible to locate and mange her nest and without management nests have a very low chance of succeeding.
Specially trained ‘kākāpō’ dogs can be successful in relocating birds with lost transmitters, but this episode led DOC electronics guru Stu Cockburn to come up with the “smart-trap”. Traps have been used to catch kākāpō since the 1970s.
The original traps were made of steel mesh and were triggered by the bird walking across a treadle on the floor. They weighed a ton and, although they caught kākāpō well enough, they also caught anything heavy enough to trip the treadle-trigger. Needless to say, this lack of selectivity was quite frustrating.
Enter the “smart-trap” – a feather-light, plastic and aluminium creation with an electronic “brain”. The trap is triggered by the unique electronic signature of the tiny PIT (Passive Integrated Transponder) tag implanted under the skin of each kākāpō’s neck. This means that it can’t be triggered by seabirds and the likes and will only catch the specific kākāpō it is programmed to catch.
And once it has caught the bird it will even Selcall a hand-held radio to alert kākāpō rangers that the bird is “in the bag”!