A little penguin was spotted dead and bloody at Aramoana Beach yesterday by a member of the public.
It was found in an area where people are known to walk their dogs off-leash.
New Zealand Penguin Initiative (NZPI) scientist Dr Hiltrun Ratz said a lot of penguin deaths did not get reported.
"To be able to protect the penguins and ensure they’re safe on their own land, we need to build a case that they’re not safe.
"If we don’t have the information then we don’t know that these things are happening."
New Zealand coastlines are habitat for various wildlife, including little penguins, yellow-eyed penguins, sea lions, seals and shags.
While many beaches have designated areas to separate beach-goers from animals, wildlife can wander beyond these boundaries.
Attempts were made to capture and release penguins that strayed from their habitat, but this was not an effective long-term solution, Dr Ratz said.
"The penguins don’t obey our rules.
"On beaches with dogs that’s just not an option really."
Unleashed dogs were not always to blame for penguin deaths, some penguins succumbing to natural causes.
"If it’s on a beach where people regularly have dogs off their leash then one could assume that some of the deaths could have been caused by the dogs, but we don’t have any proof."
A lack of people reporting made it difficult to determine the cause of death.
Reports allowed experts to retrieve the body and build a broad picture about threats to coastal wildlife.
