Animal keeper Stacey Tabellario holds Bei Bei, the National Zoo's newest panda, as he is presented to members of the media on Dec. 14. (Andrew Harnik/Associated Press)

Recently, without consulting affected neighbors, the National Zoo announced that beginning Jan. 1 its grounds will be open from 8 a.m. to 7 p.m., with a 5 p.m. closing in winter, instead of the current 6 a.m. to 8 p.m. (with a 6 p.m. closing in winter).

These changes affect multiple groups: walkers and joggers, for whom the zoo is a safe and beautiful place to exercise; pedestrians crossing between the east and west sides of Rock Creek Park; families who bring their children after school to explore ; and drivers and bicyclists who cross the Harvard Street bridge to swing down onto Rock Creek Parkway or head up to Connecticut Avenue.

Why is the zoo changing its hours? According to Director Dennis Kelly, there are two reasons: safety and security. He and his team are concerned about the potential for a collision between zoo vehicles and visitors. But no accidents have been reported, and no data have been collected about the near-misses that Mr. Kelly cited as the basis for his concern. Nor have data been collected about how many people will be affected by this change.

Mr. Kelly indicated that, without early-morning visitors, it will be easier for zoo staff members to move around on their morning rounds, which means they’ll be able to get their work done more quickly. Actually, the zoo vehicles won’t be able to move much faster because they will still have to watch out for workers on foot, other vehicles and ever-present deer roaming the zoo’s open spaces. And, in the summer, it’s light well before 8 a.m. (In June, it’s light before 6 a.m.)

The explanation for closing off car traffic, which affects only the zoo’s perimeter, is even more vague — essentially, that the zoo is not a public thoroughfare. Yes, but the zoo is an integral part of Rock Creek Park, which includes a commuter route. And the combination of this closure with the upcoming reconstruction of Beach Drive, requiring months-long closures, will significantly affect neighborhoods adjoining the zoo.

No sensible explanation has been offered for the change in evening hours.

There has been no real explanation of the security issue. There were vague references to potential terrorism, but no cogent discussion. None of us really understands how keeping out the neighbors — reducing eyes and ears who could report suspicious activity — would increase security in a park where no amount of fencing has kept out the deer who wander in from Rock Creek Park.

Bottom line: We call on officials to keep the zoo’s current hours and to consult with neighbors about how we could work together to solve any real safety problems.

Mira Marshall, Washington