The ra’ui system is the traditional method of conservation and preservation of any or all resources whether on land, sea or air. This customary management tool was revived by the Koutu Nui (Traditional leaders) on 8th February, 1998 under the direction of the then President Te Tika Mataiapo Dorice Reid. The marine resources were perceived to be under threat from over-harvesting and the intention of the ra’ui was to allow marine species to rejuvenate. This ancient methodology of the ra’ui ensures the sustainability of fish stock or any resource that are disappearing or in low supply.

The Local Government and the Government wanted to take the ra’ui system into parliament to enact it into law but the Koutu Nui wanted it under their auspices, because the co-operation and adherence to the restrictions would be respected by the community. The success of the ra’ui system heavily relies on the co-operation of the community at large, as it has no legislative powers.

In February 1998, the Koutu Nui selected the four initial ra’ui areas, Aroko, Tikioki, Pouara and Nikao. In May 2000 the Aroa ra’ui area was included (Raumea et al 2000). Since that time, more Ra’ui areas have been commissioned with varying degrees of restrictions, length of time and specific protected species (eg. Trochus).

Since the inception of the ra’ui, the Ministry of Marine Resources has been involved in monitoring, providing technical support and gathering information. These surveys are recognized as being a good indicator of changes in invertebrate species on the reef and lagoon. Surveys of these resources are established, and now form the basis of the ra’ui monitoring programme.

Purpose of Surveys

The purpose of the monitoring programme (survey) is to survey the resources in the designated ra’ui areas to see if the reef resources have rejuvenated or increased/decreased in numbers and to compare recent results against previous survey results. Past assessments include the initial baseline survey (Ponia & Raumea 1998), and monitoring surveys (Ponia et al 1998, Raumea et al 2000, Raumea et al 2001 & Saywood et al 2002), the 2004 analysed data and the 2005 survey.

In supporting the ra’ui initiative, the Ministry of Marine Resources anticipates that the series of monitoring surveys will help determine the impact the ra’ui is having in restoring the ecosystem. It will assist the Koutu Nui with facts for decision-making and provide information to create more awareness of the importance of compliance to the ra’ui system.

The four aspects of assessment of the resource species are:

  •      Population count of various resources within the five survey areas.
  •      Species distribution and diversity within survey areas.
  •      Determination and monitoring of any significant changes.
  •      Make recommendations.


Five permanent Ra’ui sites are located around Rarotonga. For sampling purposes, these areas are divided into three sections left and right outside the ra’ui (controls 1 and 2), and inside the ra’ui. Within the three sampling areas a number of transects are laid. There are 2 transects in each of the two control areas of each ra’ui. The number of transects inside the ra’ui are:

                                                Up to 2005                  2006

  • Pouara             -6 transect                   6
  • Aroa                -8 transect                   10
  • Aroko              -8 transect                   18 (not surveyed)
  • Nikao              -12 transect                 12
  • Tikioki             -4 transect                   18 (not surveyed)

The transect length was 50 meters (m) and marked at 5m intervals. Observers would systematically swim along the transect and count the number of animals within a 2m width on either side, and record these observations for every 5m band. Only animals of social or biological significance are recorded (refer to 2.1).

Various measures are used to present the results from this survey to provide information on different aspects of community and population structure:

  • Abundance (number of animals 100m¯²),
  • Incidence (frequency with which the species occurs in a transect),
  • Diversity (community composition, i.e the number of species present),
  • Evenness (a measure of the relative abundance of each species or kind in a community).
  • Species richness (number of species/kind of organism present in a community.

Although the methodology in 2006 was similar to previous years it was adapted so that transects would be placed on the reef, mid-lagoon and beach lagoon where the transect lines would fit. The surveys collected data on visual census for fish, Invertebrates, Benthic and Habitat survey.


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