Nashaquitsa Pond has become a laboratory for eelgrass restoration, although poor water quality and other factors appear to be keeping the aquatic species from re-establishing.

With Vineyard coastal ponds at a tipping point, on Thursday this week the Martha’s Vineyard Commission will lead a daylong conference Thursday.

With support from the Edey Foundation, the Chilmark shellfish department plans to restore vital eelgrass beds that vanished from Nashaquitsa Pond.

The Massachusetts Estuary Project, which studied 12 Island bodies of water, has raised awareness of growing nitrogen problems and spurred action at several levels.

A Sengekontacket oyster project has been such a success that the shellfish department will ask selectmen to open the pond to commercial oystering.

Man-made breaches at Island ponds help maintain salinity for shellfish and eelgrass and flush out nitrogen that accumulates mostly from septic tanks and runoff.