Photo: Unsplash / Alister Hitchcock
A dolphin found dead at an Auckland beach last month was killed by toxoplasmosis, the Department of Conservation (DOC) says.
The dolphin was found at Walton's Gap on the Āwhitu Peninsula by a member of the public who reported it to DOC.
The organisation's acting marine species manager Kristina Hillock said the dolphin was sent to Massey University where it was confirmed it has died from toxoplasmosis.
Toxoplasmosis is a parasite spread by cats when their faeces are dispersed by rainwater and wastewater into the sea.
Hillock said it was a threat to both Māui and Hector's dolphins.
"Analysis of several of the dead dolphin's internal organs - including its brain, heart and liver - revealed significant lesions consistent with toxoplasmosis," Hillock said.
"The toxoplasma parasite was found amongst widespread severe tissue damage which confirms the dolphin died of toxoplasmosis."
DOC was still waiting to find out whether the dolphin was an adult male Hector's dolphin or a critically endangered Māui dolphin.
It was "impossible" to tell the difference without genetic analysis as the sub-species wre "otherwise identical".
Toxoplasmosis last killed a Māui dolphin in 2010.
Hillock asked that members of the public report any dead Māui or Hector's dolphins as soon as they can as it gives scientists the best chance to carry out tests to learn more about them.