How big were those mice?

Apparently a 6ha island was over run by 68 mice, so says the Herald.


Researchers are shocked at the speed with which mice over-ran an island in the Hauraki Gulf after just two were released in a controlled trial.

In five months the pair triggered a population of nearly 70 – demonstrating the danger pests can pose to endangered native species on our predator-free island sanctuaries.

University of Auckland researcher Helen Nathan tracked the population explosion on 6ha Te Haupa/Saddle Island, which had only just been cleared of pests before the study. ??

One male and one female were individually released on to the island.

The numbers grew to 44 rodents within four months and then peaked at 68 five months after the release.

The population then stabilised and was exterminated at the study’s end.

Hmmm…six hectares…that is 60,000 square metres. How exactly did 68 mice over run this island of 60,000 square metres?

By my calculations and with a quick look at Wikipedia I’ve discovered that the average mouse is 10cm long…and let’s be generous and assume they are fat greedy little rodents and are 5cm wide…each mouse taking up a massive 50 square centimetres, which is ludicrous in reality.

Now, 68 of them times 50 square centimetres is 3400 square centimetres or 0.34 of a square metre….leaving ?more than 59,000 square metres of island left without mice.

It is impossible to say that 68 mice took over an island of 60,000 square metres…unless:

Saddle Island and the giant mice

Saddle Island and the giant mice


– NZ Herald