Virginia Marine Resources Commission members voted unanimously on Tuesday to reduce blue crab bushel limits and end the season 16 days earlier than last year.

The vote reaffirms the members’ 6-1 vote at a public hearing on June 27 to adopt the emergency measures in response to a reported drop in juvenile crabs in the Chesapeake Bay.

“They are the most important part of the next year’s spawning potential,” VMRC Fisheries Chief Robert O’Reilly said. “It’s a positive feedback system. The more ‘spawners’ you have, at least in a manager’s eyes, the better chances or probabilities you’ll have better recruitment the next time around.”

That drop was detailed in the Blue Crab Advisory Report that was developed by the Chesapeake Bay Stock Assessment Committee with approval by the Chesapeake Bay Program’s Sustainable Fisheries Goal implementation team.

The committee meets annually to review blue crab surveys and harvest data to advise Chesapeake Bay jurisdictions.

The report includes data from the annual, bay-wide winter dredge survey released on April 19, which showed a 31-percent increase in adult female crabs in the Chesapeake Bay watershed compared to last year’s survey.

Juvenile crabs, however, dropped from 271 million in 2016 to 125 million in 2017, the fourth-lowest level ever recorded by the survey. The overall crab population decreased by about 18 percent, from 553 million to 455 million, over that same span.

Juveniles are at the mercy of environmental changes, natural predators and other factors, and crab reproduction is volatile as a result.

“The biggest surprise each year is how many juveniles will be in the bay, because that’s strictly up to what happens off shore in the ocean, when the winds and currents are training small crabs back into the bay,” O’Reilly said.

The 2017 season will end on Nov. 30, and the 2018 season will begin on March 17. Reduced bushel limits for crab pots will be enforced for all of November instead of the last two weeks of the month.

Depending on a fisherman’s crab pot licensing category, this will reduce a the maximum number of crab bushels from between 10 and 47 bushels to between eight and 27 bushels.