Protections for paddlefish in the Indiana portion of the Ohio River have been adopted by emergency rule by the state's Department of Natural Resources.

The bulk of the restrictions affect commercial operators seeking paddlefish eggs for the global caviar market.

DNR Director Robert Carter Jr. took the action to protect the fish after a two-year undercover operation by DNR law enforcement revealed widespread violations of existing laws governing commercial harvest of the fish.

A drastic decline in traditional sturgeon caviar sources in Eastern Europe and the former Soviet Union has placed increasing harvest pressure on sources of caviar substitutes, such as paddlefish in the Mississippi River Basin, including the Ohio River. A mature female paddlefish may carry several pounds of eggs, which are valued at $70 per pound or more at the wholesale level, and at more than $250 per pound retail.

Undercover officers posing as fishermen were able to infiltrate the illegal operations. More than 20 suspects have been arrested to date and more than 300 charges were filed.

"Our recent investigation clearly revealed that existing regulations are insufficient to protect this unique resource," Carter said. "Unfortunately, the high market prices for paddlefish caviar do not encourage resource conservation. The escalating harvest pressure threatens to take paddlefish faster than they can be replaced, which could lead to a shortage we intend to prevent."

The emergency rule establishes a commercial paddlefish harvest season from Nov. 15 through April 15, and a minimum paddlefish size limit of 34 inches (from eye to fork of tail). The rule also prohibits the use of gill nets and trammel nets during the closed paddlefish season, and standardizes a method for commercial fishers to check paddlefish for the presence of eggs.

The emergency rule also prohibits the snagging of paddlefish by those with a sport- fishing license. Although sport-caught fish cannot be legally sold, the investigation revealed widespread snagging of paddlefish in areas of the river closed to commercial fishing being done by those with sport-fishing licenses for sale on the commercial market.