Lopez-based nonprofit Kwiaht is inviting islanders to share in a special Persian dinner at Sunnyfield Farm on Nov. 8 to support local bat research and conservation.

Prepared and donated by Lopez teacher and caterer Parvin Baharloo, dinner will be accompanied by a selection of wines from Lopez Island Vineyards, a presentation by Kwiaht director and bat researcher Russel Barsh, and a background track of “bat music” recorded over Lopez village and Hummel Lake. There will be door prizes for the diners, “mainly wearable”, according to Barsh. Diners will also be able to bid on a special wine and cheese bat-viewing evening in the spring.

Proceeds of the Bat Bash Dinner will support the installation of at least one new-generation weatherproof ultrasound recorder on Lopez, capable of monitoring nightly bat activity year-round. Recently developed by Wildlife Acoustics, a Massachusetts sound-engineering company specializing in wildlife research, it can be programmed to listen for frogs and moths as well as bats, and it can identify most passing bats to species just from their echolocation clicks.

Kwiaht purchased its first weatherproof Wildlife Acoustics recorder in 2014 with donations from the Orcas Island community, and it has been running continuously for 10 months on Entrance Mountain, recording over eight thousand passing bats.

“Acoustic monitoring is clearly the way of the future,” says Barsh, who has been studying island bats since 2010. “You can identify a hundred times more passing bats by their voices than you can trap, and many bat species are actually more easily identified by their calls than their visible anatomy.” He adds that trapping often injures bats, and while it can be exciting to handle bats, “nowadays it’s a bit like netting whales for study, when we can more easily and safely eavesdrop on their conversations from a distance.”

Bats change their foraging areas as the seasons change, and even from day to day, so the only way to obtain a relatively accurate idea of how many bats are living on Lopez is to make year-round recordings and compare them from year to year. “If you just record for a few nights at a few different places, you really cannot tell at all whether bat numbers are going up or going down” Barsh says. “Or tell whether bat conservation activities such as installing bat boxes, or protecting wetlands, are actually working.”

Seating at the Bat Bash Dinner is limited, so Barsh suggests purchasing tickets in advance at Blossom or Vortex. Tickets are $90 and they are 100 percent tax deductible as nonprofit donations. Email kwiaht@gmail.com for more details.