Landcare Research scientists in Auckland have developed DNA techniques to help identify which wildlife killers have been dining out on other species.
Dr Dianne Gleeson, who works in the ecological genetics laboratory, said forensic procedures were well developed to help pinpoint the cause of suspicious human deaths, but little work had been done on native fauna.
In the past two years scientists had refined methods which could be used in the animal kingdom, using DNA field tests to establish the species responsible for the killing.
Landcare Research was now able to offer a service to provide useful forensic information to agencies such as the Department of Conservation in efforts to protect threatened species, and to regional councils for pest-control work.
Scientists could analyse evidence such as feather fragments, eggshell remains, snagged hairs and even saliva remnants which could leave telltale cells of the culprit on a dead animal.
They genetically "fingerprint" pest species - such as possums, stoats and feral cats - using non-invasive methods. Special sticky "hair traps" were used to pull out strands of hair with DNA-rich follicles attached, and DNA could also be derived from faecal samples to build up databases of pests.
Dr Gleeson said it had been difficult to determine from remains whether a predator was a dog, cat, rat or stoat.
In some cases the scientists could now identify which individual animal was responsible and that could be useful when trying to establish whether, for instance, a single dog might be responsible for a series of kiwi deaths.
Dr Gleeson said similar DNA research had been used in the US in studies of coyotes preying on sheep.