Gray whales that like to munch on Puget Sound’s ghost shrimp each spring are back nosing around the mud flats off Everett, Whidbey Island and Port Susan.

Each April, eight to 10 of the 30- to 45-foot-long whales take a break from their two- to three-month migration north to forage in area waters.

It’s usually the same whales each year, but unlike orcas, they’re not one big family. Instead, they swim solo or in small family groups, said John Calambokidis, a research biologist for Olympia-based Cascadia Research.

“There are six animals that have been the most consistent,” he said, including one affectionately known as Patch because of a telltale splotchy white spot on its side.

Patch was one of the first confirmed sightings this year, first probably because his spot makes him easy to pick out, Calambokidis said.

Researchers use photos of the whales to identify them. Seven whales have been identified in Puget Sound so far this season.

Gray whales migrate north up the coast each spring, with most bypassing the Strait of Juan de Fuca .

The few that venture into local waters give whale watchers a treat when the region’s resident orcas are gone, said Susan Berta, program coordinator for the Orca Network, a group of whale watchers that tracks whale movements in the area.

Gray whales can sometimes be seen from shore because they feed in shallow mud flats, Berta said.

“They roll on their sides to scoop in a mouthful of mud and ghost shrimp,” she said. “They’ve got these big, hairy plates in their jaw that they use as a filter. The muddy water goes out, and the shrimp stay in.”

For Bob Dobler, the return of the gray whales is a highlight each year. “They’re a rather awesome site out there,” said Dobler, who watches the whales feed from his home on the Tulalip Reservation near Marysville. “They’re huge.”

Reporter Lukas Velush: 425-339-3449 or lvelush@heraldnet.com.