KAUAI, Hawaii — If Pierre Omidyar gets his way, 699 dairy cows will soon enjoy a glorious view of the Pacific Ocean, framed by a pristine beach.

Mr. Omidyar, the founder of eBay, wants to build a dairy farm on the island of Kauai.

He is one of many tech billionaires who have established a presence in Hawaii, which is only a five-hour flight from Silicon Valley. Others include Larry Ellison, Oracle’s co-founder, who bought all but a tiny amount of the island of Lanai and turned it into a resort — investing millions, but frustrating some islanders by driving up rents — and Facebook’s Mark Zuckerberg, who was called a “neocolonialist” after he sued some locals over beachfront land he bought. (He dropped the suits.)

The goal of Mr. Omidyar’s farm — which incidentally is on land owned by the family of Steve Case, another tech billionaire — is to decrease the island-state’s heavy reliance on imported milk, while using sustainable agriculture practices. (The dairy will nonetheless still have to import feed for its animals.)

Some residents, though, object. They and the owners of the major resorts that line this island’s famous beaches, just a little over one mile down the coastline from the dairy site, have worked to block the project.