1995: Macquarie Marshes (NSW). Ibis nestlings deaths. Pesticide: Chlorpyrifos

“Polluter Pays, Myths and Legends” Abstract
The NRA reports several fish kills in association with chlorpyrifos in water
reaching several hundred parts per billion (ppb). They also noted that chlorpyrifos may have been the cause of a major incident at an ibis rookery in the Macquarie Marshes in early 1995 in which large numbers of nestlings died, apparently from consumption of contaminated invertebrates brought back to the nest by parents. An explanation offered was the higher toxicity of the metabolite, chlorpyrifos oxon, which can reach significant levels in contaminated invertebrates. Chlorpyrifos oxon can remain undetected using standard analytical procedures because of its instability.

https://ntn.org.au/wp/wp-content/uploads/2010/02/polluterpaysmythlegend.pdf