WASHINGTON – Nearly half the U.S. Senate is pushing the Bush administration to let gun owners carry handguns and other firearms into national parks and wildlife refuges.

Forty-seven lawmakers have signed a letter asking Interior Secretary Dirk Kempthorne to lift restrictions that prevent citizens from carrying readily accessible firearms onto lands managed by the National Park Service and the U.S. Fish and Wildlife Service.

Current regulations, developed in the early 1980s, “infringe on the rights of law-abiding gun owners who wish to transport and carry firearms on or across these lands,” the senators wrote.

The policies also differ from those of some other federal agencies, such as the Bureau of Land Management and Forest Service. “These inconsistencies in firearms regulations for public lands are confusing, burdensome and unnecessary,” said the letter, drafted by Sen. Mike Crapo, R-Idaho.

Sens. Olympia Snowe and Susan Collins, both Maine Republicans, did not sign the letter, their spokesmen said Thursday.

Thirty-nine Republicans and eight Democrats signed the letter, including both senators from 17 states: Alabama, Alaska, Arizona, Arkansas, Georgia, Idaho, Kansas, Mississippi, Montana, Nebraska, New Hampshire, Oklahoma, South Carolina, South Dakota, Texas, Utah and Wyoming.

Kempthorne spokesman Chris Paolino said officials were reviewing the letter.

The regulations affect Acadia National Park in Hancock County and a half-dozen wildlife refuges in Maine.

The current regulations, adopted in 1983 under then-Interior Secretary James Watt, say visitors to national parks must render their weapons inaccessible. Guns do not have to be disassembled, but they must be put somewhere that is not easily reached, such as in a car trunk, said Jerry Case, the National Park Service’s chief of regulations and special park uses.

The rules were developed to ensure public safety and provide maximum protection for wildlife, Case said, noting that before the rules were adopted, “people would go out and shoot wildlife in national parks.” Snakes, bears, wolves and coyotes were among animals shot by park visitors.

National parks have a lower crime rate than many similarly sized communities, Case said, adding that many national parks have large campsites. “If you have people start plinking around with weapons, then you have accidents,” he said.

Lindsay Nothern, a spokesman for Crapo, said no one incident led to the letter to Kempthorne, a former Idaho governor and senator.

The National Rifle Association has long pushed for relaxation of the gun ban, but Nothern said no lobbying group was behind the letter.

The National Parks Conservation Association, an advocacy group that works to protect and enhance national parks, supports the current rules.

“There’s no reason to need a gun in a national park and it would possibly lead to unfortunate accidents and other problems, so we’d rather not see them in the parks,” said Laura Loomis, the group’s senior director of government affairs.