A 928-square-mile blue crab sanctuary within the Chesapeake Bay will be off limits to harvesting one month earlier.

The Virginia Marine Resources Commission has voted to extend the no-harvest rule.

The blue crab haven will now close from May 1 to September 15, a move up from the previous June start.

It was the second time within a month Virginia watermen have seen tighter restrictions put in place, both attempts to protect a species that has diminished to historic lows.

Despite conservation measures taken over the past decade, the crab population in Virginia is now 30 percent of what it was in 1991.

In April, the commission is expected to further limit catches.