HONOLULU, Hawaii - The last 50 wild donkeys on Hawaii's Big Island will be rounded up, marking the final step in a six-year effort to get them in adoptive homes.

The donkeys are the last of more than 500 that were cast-offs from the early days of Hawaii coffee and agricultural plantations.

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When drought conditions forced the donkeys into residential areas in search of water, the herd became a problem. The animals wandered into roadways, tore up golf courses and drank from swimming pools, said Inga Gibson, Hawaii state director for the Humane Society of the United States.

The society and Big Island residents were working Friday to prepare the donkeys for adoption. All the donkeys will get check-ups from a veterinarian before they're taken to their new homes.

"One of our first complaints was the donkeys were actually coming into the school yard," said Gibson, adding that some residents were so fed up with the donkeys that they threatened to kill them, while others wanted to use their meat to make jerky.

The herd went entirely unmanaged for nearly 40 years because the donkeys weren't considered game or endangered animals, said Gibson.

It's believed the animals were moved to Waikoloa from Kona in the 1970s when development grew in the area, Gibson said.

The Humane Society stepped in six years ago after getting calls from concerned residents. The group has spent about $200,000 to get more than 450 donkeys in homes, including 120 that were flown to California in 2011 and found homes through Eagle-Eye Sanctuary Foundation and Peaceful Valley Donkey Rescue, Gibson said.

"It was a daunting situation initially, like what are we going to do with 500 feral donkeys?"

"It was a daunting situation initially, like what are we going to do with 500 feral donkeys?" said Gibson. "It was really just an amazing community effort, and we didn't receive any kind of government support or funding."

Big Island resident Toni Schattauer was given two donkeys by a friend, and found that they helped protect her other animals like chickens from wild dogs. So she decided to adopt another two donkeys last week — Josephine and Sootie Mae — who are both pregnant.

"I had never raised donkeys before so I was a little bit nervous about that," said Schattauer. "But it's been really easy."

Waimea veterinarian Brady Bergin said a rancher is currently working to round up the last of the donkeys so they can be prepared for adoption. The donkeys are being lured into a corral using a water trough, he said. Once captured, they'll be hauled to Bergin's vet clinic.

Before adoption, the donkeys must have a clean bill of health and the males must be castrated, which is an easier and less invasive process than spaying the females, he said.

Gibson said about 80 percent of the remaining 50 donkeys have interested homes. Hopeful donkey adopters must go through a screening process to make sure they have enough land and know how to care for the animals.

It can take weeks to months to train donkeys to lead from a halter and interact with humans, Gibson said.

Donkeys are social animals, so they must be adopted in pairs or have another animal to keep them company at their new home, she said.

"The adoption clause is no lone donkey," said Gibson. "They have to have a friend."

People who are itching to adopt can fill out a pre-adoption application and email it to the Humane Society. If accepted, it's advised that the future owner stocks up on grass, hay and straw, as hungry donkeys can be a pain in the ass.

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