HILO, Hawai'i —It's tough going to bag one of the estimated 400 wild cattle roaming the Hilo Watershed.

The Big Island's hunting season on feral and trespassing cattle opened Nov. 11 in an area that stretches north from Saddle Road and along the slopes of Mauna Kea to Hakalau National Wildlife Refuge. Until Nov. 26, licensed hunters are allowed to kill and remove two cattle per day on weekends and holidays. There are no season limits.

But some hunters turned around and left when they learned the area is almost impassable because of tough terrain, thick moss and overgrown underbrush.

"It was definitely a waste of time — a ridiculous waste of time," said Cory Parsons of Waikoloa. He and a group of other hunters turned around Saturday when their truck was damaged while negotiating Wailuku River Road. And the idea of lugging hundreds of pounds of beef in backpacks over difficult trails didn't appeal to Parsons.

"You can't even hike through that stuff," he said.

The cattle in the area are seen as a threat to native forests. Tamping down earth and consuming native undergrowth, the cattle's presence promotes the growth of alien weeds.

More seasoned hunters will likely be able to make more of the hunt, said Ron Bachman, district wildlife manager. "The place is remarkable rough. The watershed is mushy and swampy, but that's why we're doing this, to keep it foresty," Bachman said. "I think when the buzz dies down, the real successful hunters will be in here."