View summary information of recorded Hector's and Māui incidents from 1921 to 2008.
On this page:
- Table summarising incidents - Hector's dolphin
- Table summarising incidents - Māui dolphin
- Explanations of cause of death categories
|Cause of death||East Coast South Island||South Coast South Island||West Coast South Island||Unknown population||TOTAL|
|Possible human interaction||6||3||9|
|Known entanglement||Cray pot||3||3|
|Recreational set net||12||9||21|
|Commercial set net||41||2||2||45|
|Unknown set net||15||6||1||22|
|Probable entanglement||Salmon farm||1||1|
|Recreational set net||0|
|Commercial set net||0|
|Unknown set net||1||4||5|
|Possible entanglement||Salmon farm||1||1|
|Recreational set net||1||1|
|Commercial set net||0|
|Unknown set net||16||10||26|
|Trauma – unknown cause||5||1||3||9|
Some summary figures:
Of the Hector's dolphins where a cause of death was able to be assessed (254 of the 415 total animals):
- 35% were known to have died through entanglement in set nets; Set net entanglement may have been the cause of death for up to an additional 27% of cases where an assessment of the cause of death was made (possible or probable net entanglements)
- 7% were found to have died through natural causes
- 7% were known to have died as a result of being caught in a trawl net
- A definitive cause of death could not be found for 9%
- Of the total Hector's dolphin mortalities, 17% were too decomposed or were too fragmented for a cause of death to be determined. A further 16% were not assessed for cause of death (mostly historical cases).
|Cause of death||Total|
|Possible human interaction||1|
|Known entanglement||Unknown set net||2|
|Probable entanglement||Unknown net||1|
|Possible entanglement||Unknown net||2|
- Human interaction
- No sign of net entanglement, but definite signs of other types of human interaction e.g. high degree of mutilation.
- Possible human interaction
- No sign of net entanglement, but indications of other types of human interaction e.g. marks that resemble knife wounds.
- Trauma – unknown cause
- As read from pathology report – trauma, with an unknown cause (i.e. could be natural or human-induced).
- Known entanglement
- Animal was known (from incident report) to have been entangled and died.
- Probable entanglement
- As read from pathology report, or presence of net marks on body and one other definite indication of capture e.g. mutilation.
- Possible entanglement
- As read from pathology report, or presence of net marks on body and a mention of this in incident report.
- Cause of death deemed to be from natural causes.
- Not assessed
- Necropsy not completed, carcass not recovered, or no assessment of cause of death undertaken.
- Not available
- Necropsy or incident report not available at present.
- Not determinable
- Cause of death not able to be determined due to condition of carcass (decomposition, fragmentation etc).
- Cause of death unexplained or not definitive (e.g. "open" diagnosis in pathology report).