Astoria Police Officer Alex Whitney brings a stray dog to the Clatsop County Animal Shelter on Friday.

The dog bolted up 15th Street, a brown blur of legs and pink dangling tongue, while fireworks boomed and blossomed over the Columbia River.

If anybody was yelling for the dog to come back, the words were lost in the sound of explosions from Astoria’s annual Fourth of July fireworks display Thursday night.

Hundreds of people lined the Astoria Riverwalk to catch the fireworks show, but some of them hurried away just as it was beginning. They carried small struggling dogs in their arms or grasped tightly onto taut leashes as larger dogs, wide-eyed and crazy-legged, dragged their owners up the sidewalk.

Fireworks had been going off all day, and for days before, in North Coast neighborhoods. At the same time, Facebook posts about lost dogs started popping up in earnest across the county. By the holiday, the Clatsop County Animal Shelter already had at least six stray dogs under its roof.

Stephen Hildreth, the shelter’s supervisor, expects more to come in for the next week.

The period between late June and early July is one of the busiest times of the year for the shelter, on the Fourth of July itself but also during the week before and a week after the holiday.

“As long as fireworks are going off, we’ll continue to get strays,” Hildreth said. “They just keep coming in.”

On Friday, the shelter had only just opened and Hildreth and his staff were already fielding phone calls from anxious pet owners who did not know where their animals were following Fourth of July festivities. They wanted to know: Had someone brought their pet to the shelter?

Astoria Police Officer Alex Whitney showed up right as the doors opened with a large brown-and-white husky in the back of his patrol vehicle: another stray.

“Fireworks, picnics and other Fourth of July traditions can be great fun for people, but all of the festivities can be frightening and even dangerous for animals,” the Astoria Police Department warned in a post on its website ahead of the holiday.

“Loud fireworks, unfamiliar places and crowds can all be very frightening to pets, and there’s great risk of pets becoming spooked and running away,” the memo continued. “Consider putting your pets in a safe, escape-proof room or crate during parties and fireworks.  Keep your pets inside if you or your neighbors are setting off fireworks.”

Astoria police spent much of Thursday responding to traffic violations, reports of illegal fireworks and lost dogs.

Each year, the shelter will see a mix of out-of-town and local animals who bolted during Fourth of July events. And there are repeat offenders, animals the shelter seems to see every July.

The holiday can have even more dire implications besides runaways. Shelter staff know dogs who have died from heart failure during the Fourth of July, stressed by the booms and explosions.

“For a lot of older dogs, it’s too much for them,” Hildreth said. “It’s pure panic.”

Some people coordinate with their veterinarians ahead of the Fourth of July to get anti-anxiety or other types of medication on board to calm their dogs before the fireworks begin. But far too many people decide to leave their animals outdoors or even bring them to events, Hildreth said.

Hildreth’s advice: Keep your pets, even indoor-outdoor cats, indoors during the holiday, and “microchip, microchip, microchip,” he said.

Collars can come loose and be lost, but a microchip, which is inserted under an animal’s skin, travels with the pet and provides veterinary offices and animal shelters with important identification information when they need to track down owners.