An attack on two carved pou is an attack on Māori and a successful conservation effort, an iwi leader says.
The posts, which mark either end of a rāhui, or customary ban, at Tauroa Pt west of Ahipara, were cut down and sawn into pieces, most likely last Friday night.
The pou were erected 1.6km apart about 10 years ago amid grave concerns for marine life, especially pāua, in the area. The attack has angered the local iwi, Te Rarawa, as well as conservationists.
Te Rūnanga o Te Rarawa chairman Haami Piripi said it was clear the ''very malicious'' attack had been planned because the pou were hard to reach and the vandal had brought a chainsaw.
The pou had been carved to mark the boundaries of a conservation area where fishing and shellfish collecting were banned.
When they were erected the area was made tapu in a poignant 3.30am ceremony attended by about 65 people. As a result the rāhui had been well respected, Piripi said.
''Māori and Pākehā, even tourists, have observed it really well. We've had incredible adherence.''
Piripi did not know what had motivated the attack ''on us and our culture''. There had been speculation it was a four-wheel-drive enthusiast disgruntled by the iwi's move last year to close off access to the dunes near Tauroa Pt.
''But we have no idea. It's quite disheartening. The conservation area has been a very uniting kaupapa bringing central government, councils, Māori and Pākehā together,'' Piripi said.
''What's broken is not so much the pou but the relationship. We don't want a return to the days when we weren't working together and were suspicious of each other. That would in turn damage the conservation effort.''
The attack on the pou, which were tapu, would have consequences.
''You [the perpetrator] will begin to feel more and more uncomfortable about your actions and yourself, guilt will creep in, and you will end up getting sick. After a while you will be exposed,'' Piripi said.
The pou would be replaced and the rāhui would remain. Māori would also continue to rebuild their role as kaitiaki (guardians) of the environment, he said.
Police had told him they were taking the incident ''extremely seriously''.
Monitoring of the conservation area had shown a huge increase in pāua numbers since the rāhui was introduced, Piripi said.