Rock lobster levels in Cape Rodney-Okakari Point (Goat Island) Marine Reserve
IntroductionHow many rock lobster (crayfish/kōura) are present in Cape Rodney-Okakari Point Marine Reserve and how are their numbers changing?
The Hauraki Gulf attracts commercial and recreational fishers from nearby urban areas, including Auckland and Whangarei. Fishers target rock lobster (Jasus edwardsii), snapper and other reef fish.
Number of rock lobster inside and outside Cape Rodney-Okakari Point Marine Reserve
Rock lobster responded positively to protection from fishing after the marine reserve was created. They were present in larger numbers inside the marine reserve in 1995 (20 years after the marine reserve was created) than ever recorded before or since.
In 1995 the average number of rock lobster per 500m2 inside the marine reserve was 4 times higher than outside the marine reserve. In 2016 the average number of lobster per 500m2 inside the marine reserve was 5 times higher than outside the marine reserve. Since 2014, the average number of rock lobster per 500m2 inside the marine reserve has been similar or lower than the number recorded outside the reserve in 1995.
Natural levels of rock lobster in the marine reserve are uncertain, so their status cannot be assessed at this time.
Note: Graphed results show the average number per 500m2 (± standard error) of rock lobster of all sizes, including those smaller than the legal size. No suitable monitoring data is available from before 1995.
There has been a decline in the average number of rock lobster per 500m2 in the last 10 years. The monitoring survey in 2016 recorded one third of the rock lobster recorded in the 2006 survey.
A similar declining trend has been observed at Tāwharanui Marine Reserve in the last 7 years.
DOC has commissioned regular counts of rock lobster in the marine reserve and at nearby non-reserve sites since 2000.
Data analysis to derive the status and trend of snapper at Cape Rodney–Okakari Marine Reserve is underway in 2016. It is not included in this report card.