And so Squirrel Week ends as it began: with Answer Man contemplating the black squirrels of Washington.

The arrival of these dusky denizens in the District is well documented: They were imported from Canada by the Smithsonian in the early 20th century and set free. Since last Sunday’s column, Answer Man has heard from dozens of readers eager to delineate the ever-expanding range of the black squirrel.

There is a “substantial population” at Fort Meade. They are in Potomac, near Swain’s Lock. And in Falls Church. There is at least one in Overlook, just off Edsall Road in Alexandria, and at least two in Alexandria’s Beverly Hills/Del Ray area. You can find them in Wheaton and Frederick, Fairlington and Annandale, Oakton and Lake Barcroft, Winchester, Va., and Westminster, Md.

Bay Ridge at the very end of Annapolis Neck on the Chesapeake is “overrun with the critters,” Tip Clifton reports. So is the Drum Point section of Lusby, in Calvert County. There are black squirrels in White Post, Va., 60 miles west of Washington. “In fact it is a rarity to see a gray one,” wrote Michele Worthing.

Black squirrels inhabit McLean, Columbia and Centreville. Chantilly? Apparently. They arrived in Groveton, a neighborhood in southern Alexandria, last year. They are in Reston, on the south side of Sunset Hills Road. They are at Cameron Station and in George Washington Park, near the Masonic Temple.

My old colleague Hank Burchard grew up in Arlington and said he contributed to the rise of the black squirrel between Clarendon and Buckingham. As a boy he would dispatch squirrels with his pellet gun. His mother forbade him from shooting black ones. Wrote Hank: “They were fairly rare, but as I subtracted some hundreds of grays from the population over the years, the blacks became more and more common, till by the time Mother died in the 1980s, grays were the rarities. This is still the case, I’m told.”

A black squirrel visits Bettye Speed’s home on remote Kent Island. Wrote Bettye: “He must have been transported by car via the Bay Bridge, by boat or flown in as a stowaway, or — heaven forbid! — swum the Chesapeake Bay!”

Answer Man also heard from residents of New Rochelle, N.Y.; Princeton, N.J.; Syracuse, N.Y.; Detroit Lakes, Minn.; Wooster, Ohio; Grayling, Mich.; the Bronx; Kent State; Haverford College; and Texas Hill Country, all wondering how black squirrels got in their neighborhoods. Sorry. Answer Man has his hands full with the Washington area. You will have to consult your local newspaper columnists.

Brian French has a cottage at Rondeau, the Canadian park that was the original source of the Smithsonian’s black squirrels — and which got some of our gray squirrels in return.

“Clearly your imported black squirrels are doing a little better than our imported gray squirrels,” Brian wrote. “We certainly do have gray squirrels in the park. However, they are relatively rare and cause great excitement whenever Rondeau’s children spot one.”

Answer Man found it fascinating that readers discerned personality differences between the grays and the blacks — although no one could agree on what those differences are.

Linda from North Chevy Chase village wrote that the three black squirrels who visit her patio “are very well mannered as compared to the gray variety.”

Andrea Burgard of Leisure World said her black squirrels “appear to be more aggressive than the grays in my yard.” But Barbara McJoynt of Mount Vernon said it’s the gray squirrels that chase the lone black squirrel from her yard.

Arlington’s David Chisman has noticed the same gray-on-black violence as Barbara. “I am rather reluctant to say this, but it looks like squirrel racism,” he writes. “Can such a thing exist?”

Smithsonian squirrel expert Richard Thorington Jr. said, “I don’t think the melanism gene conveys any behavioral differences of that sort.”

Hyattsville’s Imani Kazana enjoys seeing the black squirrels. “I am also black,” she wrote, “and have related to their minority, and possibly brave, status in this hostile society. . . . As they have survived and spread through the region, people of color have as well, despite the racism and odds. They have provided hope and inspiration to me personally over the years.”

What about Washington’s white squirrels? Their story will have to wait until next year’s Squirrel Week, tentatively scheduled for April 8-14. Mark your calendars.