Preserving a natural resource usually entails sacrifice, at least for the short term. The state Board of Land and Natural Resources, principal stewards of Hawai'i's land-and-sea treasures, has taken an important step in the right direction by approving a fishing ban in an area that needs intervention if its reef, the habitat of many marine species, is to survive.

The sacrifice for that area, from Kekaa Point to Honokowai Beach on Maui, is that the fishing community won't be permitted to harvest sea urchins or any of three families of popular reef fish: parrotfish, surgeonfish and chubs.

The reason: These species help keep seaweed growth in check. Because they've been overfished, the natural balance has been upset, and now seaweed has begun to smother the reef.

This is a rule change that marks a welcome, proactive approach and promises a great benefit to the health of the reef. Gov. Linda Lingle should give it final approval.

Further, the Department of Land and Natural Resources should consider expanding this management tool to other coral reef zones that face similar threats throughout the state: Hawai'i should be more aggressive in taking additional steps to protect its reefs.

Compared to Guam and Australia, where a respective one-fifth and one-third of coastal waters are designated "no-take" zones, less than 1 percent of Isle waters are restricted in this way.

No-take zones are controversial. The fishing industry and some other critics say that there are culprits deserving of more blame for reef degradation than overfishing. Silt runoff from denuded parcels of land have crippled other marine ecosystems, and natural forces, such as storm surges, take their toll.

Fishery groups complain that they are being unfairly targeted by the effort. In fact, the state must monitor the Maui area carefully to note the recovery of the reef and lift the restrictions once that becomes practical.

But it would be a mistake to pass by an opportunity to correct an environmental imbalance. Allowing the reef to be overwhelmed will render it a marine desert, potentially destroying the habitat for good. And near-shore fisheries have become rare enough as it is.

Many people look on fishing as an integral part of their life, even part of a cultural gathering right. But the native culture also enforced rest periods for fisheries, to ensure stock for future generations. This is a time for bringing that wisdom into the modern age.