It is estimated that over the 35 year life of Comalco's Weipa bauxite mine 2.6 to 4.7 million amphibians and reptiles (equivalent to 9.6-28.4 tonnes of biomass) have fallen into uncapped exploratory boreholes.
This is unpublished work presented and recorded in the 'Proceedings of the postgraduate conference of the Department of Zoology, James Cook University' in 1994.
You can get the PDF scan of the printed proceedings pages for free from my Products page.
The presentation was memorable as it was the first time a MacBook computer had been hooked up to a projector. At one point the cable fell out of the port and there was a collective gasp as I walked around and simply plugged it back in. Everyone (except me) was expecting the projector or the PC to blow up, which is what did tend to often happen in those early days of PC's.
It was also notable because I used HyperCard to create an animation of what was happening with fauna falling into the boreholes. Because of a default setting in the step where the reptile fell the computer emitted an unplanned sound like a squeal. The audience laughed, which was extremely rare, but it totally distracted me and so I forged on with the content. I worry it made me come across as humourless.