Possum behaviour helps inform predator trapping

Research into possum behaviour is helping inform predator control work on Taranaki Maunga. 

Theo O’Malley’s research for her PhD – carried out between 2018 and 2021 and submitted last year, investigated predator behaviour, including the home range of possums and their interactions with different types of traps. 

Theo found possums have a large variation in their home range, some ranging from 10 hectares while others were roaming up to 100 hectares. While the findings raise more questions, it’s helped predator control work, such as working out the minimum spacing of traps that works best for catching possums in areas where numbers of possums are low. 

Theo also discovered possums had a low rate of interaction with two out of three types of traps. More interaction was occurring with leg hold traps and very little interaction with two other trap types. “The possums would often come up and engage with the traps and lick them for example. But in order to catch them they needed to put their head inside it. Moving forward a key question is, is there a way we can redesign them to improve their interaction, such as design features and the orientation of the door openings.” 

She captured and recaptured possums to fit collars for tracking, and got to know their personalities, from timid and reserved to aggressive. “It brings some awareness that you are dealing with an animal that has emotions and has value as an individual. We need to always consider the welfare of the animal but that doesn’t change the fact that they are an ecological hazard and if you don’t remove them it impacts the ecosystem and native animals will die.” 

Theo is making final edits to her PhD and is due to start a Postdoctoral in Germany in August looking at the evolution of culture in animals. She said she really enjoyed her time in Taranaki and working with people from Taranaki Mounga Project, Taranaki Regional Council and Manaaki Whenua Landcare Research.