Kia ora Alec
Yes - it might be possible to identify a species from feathers etc found in a nest (with the slight caveat over who will pay for any DNA analysis if required), but there will still be a need for detailed information (and preferably images) of what was observed at the site to interpret the findings.
One of the challenges here is that egret species often roost together. There are many records of white heron and cattle egret roosting together in New Zealand, and it would be easy for a non-birder to interpret this as an adult (or even pair of adults) with young. If a feather (or DNA extracted from it) allowed identification of one of these species, this would not confirm that breeding had occurred. Similarly, a nest by itself does not mean that an egg was laid.
Hopefully images can be retrieved, but from the information so far available, I suspect that we might need to wait for the next breeding season before there will be sufficient information to stand up to Records Appraisal Committee scrutiny.
Last edited by Colin Miskelly
on Thu Apr 30, 2020 8:52 am, edited 1 time in total.