Monitoring
Debbie Freeman and Trenet Paenga
measuring crayfish
How has marine reserve status helped the sea life in the area?
DOC is monitoring the changes in the Te Tapuwae o Rongokako Marine Reserve to measure the project's results.
Rock lobster, fish, kina, paua have been monitored annually since 1999, with the rocky shore being monitored for snails and seaweeds in 1999 and 2003. The results show that there are more large blue moki, snapper and tarakihi are more commonly seen, the paua are larger and more abundant, and kina are larger, but there are fewer of them.
There have been significant changes in the lobster populations both within and outside the marine reserve over the last five years.
The population structure, movement and growth of spiny lobsters (Jasus edwardsii)
Lobster pots and divers have been used to survey populations within and outside the marine reserve to assess how lobster population distribution, abundance and structure respond to fishing intensity. In addition, a tagging study of over 7000 tagged spiny lobsters has been undertaken to describe the growth rates and movement patterns of lobsters in areas of varying lobster density, including fished and unfished reef systems. This was the largest tagging survey to ever be undertaken in a New Zealand marine reserve.
Results
- Lobsters are a lot more abundant within the reserve than in surrounding areas, and there are larger amounts of legal-sized fish.
- With more large males in the reserve, females are producing more eggs that the same-sized females outside the reserve.
- Undersize male lobsters within the reserve are growing faster than same sized lobsters caught outside the reserve.
- Lobsters have seasonal movements, particularly within reefs. Some movement of lobsters across the marine reserve boundary takes place (both into and out of the reserve), especially where the reserve boundary crosses reef.
- Lobsters have been seen eating one another as well as foraging during the day in the reserve. This might be because there's more competition for food. This behaviour has not been reported on before.
- Lobsters caught outside the reserve were in poorer condition, with lower body weights. There were also more fish affected by a bacterial infection thought to be partly caused by being handled.
A thesis has been prepared about this research so if you'd like to know more contact us using the details under find out more.
Contacts
Further information about the reserve is available from the:
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Gisborne Whakatane Area Office
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Phone:
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+64 6 869 0460
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Fax:
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+64 6 867 8015
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Email:
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gisbornewhakatane-ao@doc.govt.nz
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Address:
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63 Carnarvon Street
Gisborne 4010
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Postal Address:
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PO Box 668
Gisborne 4040
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