Leonardo Da Vinci’s masterpiece: Lady with an ermine (stoat) was painted in 1489-90. The large size of the animal is largely symbolic; the white winter coat signifies purity and moderation.

This post continues exploring the history of engaging the public in stoat research in 1970s New Zealand. In the last post, I described research carried out by Dr Carolyn (Kim) King, an expert on mammalian predators in the unique NZ context. Future posts in the early days of #CitSciNZ series – on wasps and birds, will explore other research initiatives involving members of the public that were considered novel at the time.

Stoats 101

Stoats are extraordinary creatures. Long and sleek, they move like liquid. They are nimble climbers and can swim to islands over 1.5 km away, or possibly further if rafting on floating debris. Their ability to move rapidly and live in any where they can hunt prey makes them a formidable enemy for our native wildlife. They are mustelids – a family of small to medium sized carnivorous animals which includes ferrets, weasels (both also introduced to NZ), along with badgers, otters and wolverines. The natural range of stoats (also known as ermine) extends from North America across Eurasia, and from the arctic regions to temperate regions.

The natural range of the stoat – Mustela erminea (in green). Image sourced from https://www.wikiwand.com/en/Stoat

They are voracious and relentless hunters… having only two reasons for living – to eat and to reproduce. https://www.doc.govt.nz/nature/pests-and-threats/animal-pests/stoats/

Engaging the public

In 1979, Dr Carolyn (Kim) King set up another project – this time to create a database of known aged stoats. Stoats develop lines (like growth rings) on the root of their canines, and these were suspected to appear annually. Just before the 1979 seed fall in Fiordland, 130 stoats (including more than 100 born in the that year) were live trapped, anaesthetised, then ear tagged and released. A poster hung in prominent public places (e.g., pubs) explained the study and asked that dead or trapped stoats with ear tags be sent back to Kim at the DSIR. This way, the dates of first capture and retrieval could be used to estimate the longevity of each stoat. Despite the information provided, some folks still ‘got the wrong end of the stick’…

What fool dreamed up such a ridiculous venture? No wonder our forests and wildlife are in danger when such asses are allowed free play with their hare-brained schemes Unpublished letter 

The fact that ‘some people still thought we imported and released stoats’ stunned Kim, given the poster explained that these were young adults, born and caught and released in Fiordland.

Excerpt from NZ Herald, 1980

Over the next 2-3 years, 22 stoats were received, and then sent to a specialist in Denmark to age each specimen. Analysis showed the lines were annual and laid down in winter, which meant a robust age structure could be developed. Kim admits that if she had been able to travel to Fiordland and talk to people, then the study may have been more effective:

At that time, I didn’t know how important it was to get the community on board… but we’re talking about the 1970s and early 1980s. The whole idea of engaging people in some scientific decisions wasn’t thought about then.

Communicating science

With the rise and rise of social media we have entered an era where information and misinformation flows freely, and with alarming speed. Information ecosystems are complex and networks far more extensive than ever before. The ability to respond anonymously in largely unmoderated fora has proved verbal dynamite. In comparison, the overall tone of the unpublished letter from Kim’s study is one of indignation, rather than bullying or worse, threatening. While it’s unlikely studies such as Kim’s pioneering work could be conducted today (despite the solid scientific foundation), much continues to be learnt about how best to manage and control pest species in NZ.

References and further reading

King, C.M. & Moody, J.E. 1982 The biology of the stoat (Mustela erminea) in the National Parks of New Zealand V. Moult and colour change. A suite of papers in New Zealand Journal of Zoology 9:49-144. Available: https://www.tandfonline.com

King, C.M. 2019. Invasive Predators in NZ: Disaster on Four Small Paws (e-Book & Hardcover). Available: https://doi.org/10.1007/978-3-030-32138-3

King, C.M., Gaukrodger, D.J., & Ritchie, N. (Eds.) 2015. The Drama of Conservation: The History of Pureora Forest, New Zealand. Available: https://www.springer.com/gp/book/9783319184098

Grue HE, King CM. 1984. Evaluation of age criteria in New Zealand stoats (Mustela erminea) of known age. NZ Journal of Zoology. 11:437-443.