The biodegradable possum bait station

Find out how Potatopak (now re-branded as earthpac) has used the unique features of potato starch to develop and make a biodegradable possum bait station.

Possum

Possums are one of New Zealand's biggest pest species – eating native trees, birds and invertebrates, and destroying ecosystems.

Rights: Craig Hill, licensed through 123RF Limited

Potatopak began by producing a range of plates, but is now developing other products. These products often replace existing ones that have a harmful effect on the environment. Potatopak can design new products to meet the specific needs of a client, an example of this is the possum bait station.

Possum bait stations

In New Zealand, possums are a pest, their numbers are controlled by trapping or poisoning. Poisoned bait is left in a bait station – a small open-sided container – fixed to a tree or post. Bait stations made of synthetic plastics, will remain as waste in remote areas. Potatopak have recently made a biodegradable alternative.

Potatopak’s possum bait station is similar in design to tradional bait stations, but both the bait and the bait station can be eaten by the possum! Anything remaining will biodegrade within four weeks with no harmful environmental effects.

Developing the bait station

Potatopak had to design and build a special machine and moulds to make the bait station. While plates and containers are flat and simple shapes, a mould for six bait stations has multiple fine-walled compartments and a complicated shape, so designing the product was a very long and expensive process.

Possum bait station

The final biodegradable possum bait station product incorporated three compartments for the bait.

Rights: The University of Waikato Te Whare Wānanga o Waikato

Potatopak is the only manufacturer in the world with a machine that can produce such complicated shapes out of potato starch.

Testing the bait station

The bait station was tested in field trials to make sure it was safe and effective. Testing took two years. Three trials were done, and the trial process resulted in a design modification to include more compartments. After testing ERMA (the Environmental Risk Management Authority) gave approval for the bait stations to be used in New Zealand. In total, 2,250,000 units were made and are in use across the country.