March 20th 2018
Our new project is underway!
We have begun piloting a new technique which we will hope will teach us more about the health of our local Hector’s dolphins.
We are using a sampling technique never before attempted with this species known as ‘blow sampling’ to determine whether it can be used to detect infectious diseases.
This method has been used successfully in the past with orca, humpbacks and bottlenose dolphins, and requires us to capture the air and water expelled from the Hector’s blowhole (basically dolphin breath!).
We do this using a petri dish on the end of a long pole, and the samples are then labelled and sent away for analysis at the Institute of Veterinary, Animal and Biomedical Sciences at Massey University.
This project was prompted by the discovery of a new disease within our local Hector’s dolphin population.
In December 2016 a Hector’s dolphin that washed near Harnett’s Creek, Kaikōura, was found to have died from tuberculosis. The bacteria that causes this particular strain of tuberculosis, Mycrobacterium pinnipeddi, is common in fur seals in sea lions, and has been reported seven times in New Zealand beef cattle, but has never before been found in cetaceans (dolphins, whales and porpoises).
Hector’s are only found around New Zealand, and are already listed as endangered, so it is crucial that we understand how infectious diseases such as tuberculosis are making their way into our local dolphin populations.
One possibility is that human related pollution and pathogens can be washed into the ocean following heavy rains. This phenomenon is known to have caused the deaths of sea otters off the California coast. In this case the otters were found to be infected with a parasite called Toxoplasma gondii which comes from cat faeces.
We are hoping that blow sampling will allow us to detect the presence of this, and other, infections– a first step in determining where the problem is coming from and devising a strategy to better protect our dolphins from this new threat.