Hector's dolphin incident database
The Department of Conservation administers a database containing information from reports received relating to deaths of Hector's and Maui's dolphins. Reports may be of dolphins:
- washed up dead on the beach
- found floating dead at sea or
- caught during commercial or recreational fishing (bycatch)
Where reports come from
The database relies on reports from the public of dead dolphins they have found and so is biased against areas that are not visited frequently by people and so tends to have more reports from areas that have higher visitor numbers. The database also relies on reports from fishing vessels that may have caught dolphins during their fishing activity.
The earliest record in the database is from 1921. Some reports are historical records from museums or universities, but much of the information in the database is from reports investigated by the Department of Conservation.
Currently, investigation of all Maui's and Hector's dolphin mortality includes:
- photographing the dolphin as it was found
- taking samples and measurements
- necropsy by veterinarians (the animal equivalent of an autopsy or post-mortem) to determine the cause of death and collect additional scientific samples and information.
What the database contains
The database contains a variety of information about each dolphin, including its sex, size, where it was found, any background information about the incident and information collected during the necropsy.
In some cases, dolphins may not have been assessed for a cause of death, or the carcass may have been too decomposed to find out how the dolphin died. In other cases, there may be clear evidence for a dolphin's cause of death (for example, a specific wound) - in some cases, there may be no clear evidence at all for the cause of death.
Quarterly Updates
The Department of Conservation recognises the public's interest in the conservation of Hector's and Maui's dolphins. In order to provide a more efficient way of keeping people informed quarterly updates are posted here detailing the number of incidents recorded in the quarter.
Updates will be loaded in early May, August, November and February each year.
In order to align reporting and maintain the integrity of government fishery observer programmes, data on observed captures will generally be reported here only in the quarterly report after the quarter that the incident occurred in.
As this is a new system for informing the public please provide your constructive feedback to marinemammals@doc.govt.nz