FRESNO, Calif. — Federal law now allows visitors to carry guns in national parks, but you can’t just slip a loaded pistol into your backpack and take a hike.

Pay attention, because this is a little complicated.

You will need a concealed weapons permit to carry the loaded gun in the backpack. But you don’t need any kind of permit if you just want to stash your loaded weapon in the tent.

At the same time, unless you feel your life is being threatened, don’t shoot the gun at all.

What’s going on? Firearms in national parks are now under both state and federal restrictions, and the result can be confusing.

State law generally applies to the way guns are carried and how a concealed weapons permit is enforced.

California’s odd exemptions to the concealed weapons rule include sleeping in a tent, which is considered your temporary home.

Federal restrictions aim at a bigger picture. They do not allow guns in many federal buildings, such as park visitor centers. They also forbid hunting, target shooting or even firing a gun.

“The fact is, you still can’t use a weapon in the park,” said Steve Shackelton, former chief ranger of Yosemite National Park. “I don’t think we’ll see much of a difference with this law in Yosemite.”

Still, officials across the country now must make sense of differing state gun laws in each national park as the tourist season approaches, said Shackelton, who is now associate director for visitor and resource protection for the National Park Service in Washington, D.C.

Federal laws

Supporters of the new federal law said it makes national parks consistent with policy over vast federal acreage in national forests where carrying a gun is legal. They say carrying a gun is a right protected by the Second Amendment.

But passage of the law disappointed rangers associations and the National Parks and Conservation Association, a parks advocacy group based in Washington, D.C. They tenaciously opposed the law for years, fearing an increase in wildlife poaching and danger to visitors.

The opponents ask: Will someone get hurt if a nervous camper fires a gun to scare away a bear?

“We don’t know what will happen,” said Bryan Faehner of the Parks and Conservation Association. “That’s why we fought this law tooth and nail.”

Though Shackelton does not expect problems, he said there may be incidents that will require rangers to take action. For example, he warned hunters not to use the sighting scopes on their rifles to admire deer or other animals in the distance. “We don’t know if the rifle is loaded or not,” he said. “So we will seize it.”

Rangers and other federal officials will focus on educating visitors about rules and safety, Shackelton said. Many visitors won’t carry guns anyway, he said.

State laws

But there will be challenges in observing some state laws, especially in places such as Yellowstone, which includes parts of three states — Wyoming, Montana and Idaho.

Montana recognizes concealed weapons permits from more than 40 states. Wyoming recognizes fewer than 25 states. A visitor may own a permit from a state that is legal in Montana, but the same permit may not be legal in Wyoming.

California doesn’t allow concealed weapons permits from any other state.

That’s not the knock on California’s law, though. The law is just confusing, said Mike Stollenwerk, co-founder of OpenCarry .org, an Internet-based group supporting the right to carry holstered handguns.

Without a concealed weapons permit, it is illegal to carry a loaded firearm on the body in urban public places, according to the California law.

But it is legal to carry the loaded weapon if you are in the act of hunting or fishing. It is also legal to have the loaded firearm in a person’s residence, motel room, campsite, business or on private property.

Another point of contention: A loaded firearm can be carried openly in an unincorporated area without a concealed weapons permit, unless the area forbids firing weapons. Yosemite officials say the park qualifies as an unincorporated area with a gun-firing ban.

But Stollenwerk said he is not so sure that Yosemite or any other national park can qualify for the gun-firing ban under state laws.

He said California’s law could be interpreted to apply only to local jurisdictions, such as counties, not the federal government.