Humane Society of the North Bay manager William Oglesby was just leaving work at dusk on Wednesday night when he saw something that made his stomach drop — several large animal carriers by the side of the road, all packed with adult cats.

“At first I counted 19, but after we started pulling them out individually we counted 17,” he said.

The cats were in various stages of health, from thin and sickly to obese. At least 75 percent of them were over 10 years old, and many of them had advanced teeth and gum issues, he said.

“It’s absolutely heartbreaking to see something like this and know that they were suffering before they got to us,” said Kristin Eddy, president of the Humane Society board of directors.

Strangely, they were organized in each crate by color or breed, with all the black cats in one, all the tabbies in another, etc.

Since many of them had similar health issues, there’s a good chance they all came from the same person or household, Oglesby said.

Finding answers in situations like this can be difficult.

“It could be somebody who just felt overwhelmed themselves and finally got it together to bring them down to have them taken care of,” Eddy said.

The arrival of all these cats is placing a greater financial burden on the shelter, which is currently experiencing a big furry glut of felines.

“It’s kitten season, so it’s a double-whammy,” Eddy said. “In every shelter, everywhere, there are a ton of kittens.”

Older cats are less likely to be adopted, but both Oglesby and Eddy said they were going to do their best to first bring these cats up to optimal health and then find them homes.

Oglesby initially took a video of the kitties and put it on Facebook, which prompted a flurry of fury from some animal lovers who condemned the person who dropped off the cats.

But the Humane Society wants to make it clear that shaming people who drop off their animals is not a good approach.

“We want to make it more of an educational opportunity,” Eddy said. “If you make it too hard for people to drop them off and be in a safe environment, then something even worse happens to them,” she said.

Oglesby agreed.

“As tragic as this is for these guys to come to us in this way and be left out in the street, this is the best way. At least they are safe and not running around or dumped somewhere else.”

So far the cats seem to be comfortable in their new digs. They have taken over the room usually set aside to test the temperament of dogs.

“They’ve done really well given the amount of stress that they went through,” Oglesby said.

The thinner cats were tested for feline leukemia and FIV and the tests came back negative, but further veterinary examinations are on the way.

So how can people help?

Oglesby said that donating to the shelter’s Second Chance Fund, will go to help cover the costs of vet care and food. Dental work on cats can range from $400 to $1,000, so the price tag isn’t going to be cheap.

The shelter also welcomes anyone who wants to adopt one of the cats and cover the vet costs.

“Getting homes will be a great challenge,” Oglesby said. “If someone wants to let them live out the rest of their lives in the way they deserve, we don’t need to keep the cats until they are perfectly healthy. If someone’s willing to jump in and say, ‘I’ll take that old cat, I’ll get those teeth taken care of,’ we would be grateful.”

There are other ways to help out even if you can’t make donation to the Second Chance Fund or adopt. The shelter can always use trash bags, hand sanitizer, Clorox wipes, and paper towels, for example.

Donations to the Second Chance Fund can be offered on the shelter’s website, www.hsnb.org. The Humane Society of the North Bay is located at 1121 Sonoma Boulevard, in Vallejo.