A new $10,000 fund to subsidize pet health care for Island families is an unexpected bonus that will be part of the final transfer of the Edgartown animal shelter site originally donated by Katharine M. Foote.

The fund, which will be formally announced at a meeting of the Dukes County Commissioners today, is for Vineyarders who may not be able to afford care for their animals on their own.

The fund, the property and equipment are being donated by the Massachusetts Society for the Prevention of Cruelty to Animals, which ran the facility for 50 years until 2009.

At that time, the Animal Shelter of Martha’s Vineyard was formed by volunteers as a public-private partnership with the county. The MSPCA has provided an open-ended, no-cost lease for the group to use the facility for the past two years.

The formal donation of the property has always been part of the plan, according to a statement by MSPCA president and chief executive Carter Luke, once the Animal Shelter of Martha’s Vineyard qualified for nonprofit tax status. That process is underway with the federal government. The final transfer will be completed when the organization is designated as a charitable, tax-exempt group.

The fund will be administered by the Animal Shelter of Martha’s Vineyard, the MSPCA statement said.