Up to 10 carcasses a day are being found in the grounds of Morisset Hospital.

Concerned wildlife rescue carers raised the alarm, prompting a joint investigation involving the RSPCA, Department of Primary Industries, Taronga Zoo experts, the Office of Environment of Heritage and others.

Initial findings show no evidence of malicious poisoning and that the kangaroos have been infected with a blood-borne parasite called Babesia.