If everyone can agree on the need to restore the populations of onaga and opakapaka in the Main Hawaiian Islands, there still remains the task of deciding how this can best be done. Here are some of the options, as well as their drawbacks.
Minimum Size Increase
Since 1925, one-pound minimum size restrictions have been placed on the sale of onaga, opakapaka, and certain other bottomfish. The catch of smaller fish is not prohibited; merely their sale. The rationale for this is the belief that fishermen will throw back all fish that they cannot sell, allowing the released fish to grow to maturity. With as many recreational fishermen as Hawai’i has, these minimum size restrictions may be of limited value.
Another drawback to the size minimum is that few fishermen other than the most experienced ones are able to target larger fish. Undersize fish are caught as well as larger ones. Releasing the small ones costs the fisherman time and trouble.
In the case of both onaga and opakapaka, however, the release of young fish is further complicated. When these fish are brought to the surface suddenly from the depths at which they are hooked, the effects of the rapid decompression can cause their air bladders to explode and their stomachs to pop out of their mouths. Fishermen can try to push the stomachs back down the fish’s throat before throwing the fish back into the water. But even then, the prospects that the fish will reach maturity are slight. In the water around the fishing vessel, the released fish are easy prey for larger fish, birds, or porpoises.
The Division of Aquatic Resources has a tagging program for young opakapaka. Techniques for fish release developed there (involving, among other things, the puncturing of the air sac) show that this can be done with a relatively high level of fish survival. By all accounts, however, undersize onaga are far more fragile than opakapaka.
Finally, the existing one-pound minimum is not high enough to allow opakapaka and onaga to reach spawning maturity. For onaga, size of most fish at first breeding is roughly 10 pounds; most opakapaka in the Main Hawaiian Islands reach breeding size at three pounds.
Over and above the problems associated with releasing undersize fish and the inadequacy of the existing size minimum, fishermen have already indicated their resistance to any increase in minimum size. In February 1993, the Western Pacific Regional Fishery Management Council held public hearings on its proposal to increase to three pounds the minimum size for opakapaka caught in U.S. waters. Few fishermen supported the proposal, citing market demand for smaller fish, concern for “wastage” of undersize fish, inability to target larger fish, and the like. Without support from fishermen, proposals for any minimum size increase are not likely to win legislative approval.
Maximum Size Limits
One management approach might be to require fishermen to release any onaga over a given size. The idea behind this is to keep large, healthy spawning fish on the job. Enforcement would be all but impossible, however. Even among its supporters, this tack is regarded as unworkable.
Seasonal Closures
Closing the season could be done by the Department of Land and Natural Resources through its rule-making process. This approach is the one favored by the Western Pacific Regional Fishery Management Council.
But the closed season is not problem free. If the taking of just onaga is forbidden during a closed season, vessels will still be on the water trying to catch other fish. Some limited targeting of the catch is possible (setting hooks at depths shallower than those where onaga are generally found, for example), but still there is no certainty that catches of the out-of-season fish will be avoided.
Also, there is the problem of enforcement. Closed seasons are easiest to enforce when fishing is prohibited in a given area for all types of bottomfish. This, however, creates a hardship for fishermen and disrupts the wholesale fish market.
Area Closures
This is a variant of seasonal closures. Rather than ban fishing (for onaga or for all bottomfish) during a certain period, the state would designate certain areas to be off-limits for periods long enough to allow depleted stocks to be restored.
The drawbacks are that this might increase fishing pressures on areas still open. Also, it will cause hardship for some fishermen who will need to travel greater distances to get to open fishing grounds.
Little is known about the length of time it might take to get fishing stocks restored to the point where they can be exploited again. If this should be on the order of years, even decades, rather than months, opposition to this approach will probably doom its chance for adoption.
Catch Quotas
The state could impose a bag limit on the number of individual onaga, or the total weight of onaga, caught in a given day or on a given trip. All other things being equal (that is, the number of fishermen and effort they make remaining constant), this approach could increase the spawning stock of onaga. At present, however, the state has no way of ensuring that these other factors will remain constant.
One advantage to this approach is that it allows the fisherman who has reached his daily quota to continue to fish for other species if he is not yet ready to head home. But here, again, there is no guarantee that onaga won’t be the unintended catch. If this occurs, the problems associated with release of onaga arise once more. Enforcement of this policy would be difficult and costly.
— Patricia Tummons
Volume 4, Number 9 March 1994
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