The last of the herd of wild donkeys that once roamed freely on the south slopes of Mauna Kea in Hawaii are being adopted.

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

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

Drought conditions forced the donkeys into residential areas in search of water. The animals started going into roadways, tearing up golf courses and drinking out of swimming pools, said Inga Gibson, Hawaii state director for the Humane Society of the United States.

The Society and Big Island residents are starting work today to prepare the donkeys for adoption. All donkeys will get check-ups from a veterinarian before they’re hauled off to their new homes.

“One of our first complaints was the donkeys were actually coming into the school yard,” said Gibson, adding that some Big Island 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 they weren’t considered game or endangered animals, said Gibson. It’s believed the donkeys were moved to Waikaloa 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. Since then, they’ve spent about $200,000 to get more than 450 donkeys in homes, including 120 who were flown to California in 2011 and found homes through Eagle-Eye Sanctuary Foundation and Peaceful Valley Donkey Rescue, said Gibson.

She said about 70 to 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. Donkeys are social animals, so they must be adopted in pairs or have another animal for company.