Six weeks after the Los Angeles wildfires erupted, Chris Briffett was sifting through 10,000 volunteer applications. The director of volunteer services for Pasadena Humane, a nonprofit, is expected to bring on about 2,000 – giving the organization an “unprecedented” chance, he says, to respond to the community’s needs.

“It’s now kind of a new chapter in the shelter’s history to find places for them to help,” says Mr. Briffett.

When communities are devastated, people step up to help, often in ways that align with their own skills or interests. But in the past decade, more trained volunteers have been integrated with official disaster response, says Tricia Wachtendorf, co-director of the University of Delaware’s Disaster Research Center. The inclusion of volunteers in the government process of planning for emergencies, she adds, improves coordination in the midst of disaster.

Christine Quesada, director of volunteer programs for LA County’s Department of Animal Care and Control, says volunteers were vital during the wildfire evacuations at LA Pierce College, which took in horses and other livestock. LA County’s Equine Response Team — volunteers trained to work with large animals — provided food and care; worked with organizations for donations of food and supplies; and cultivated relationships with owners.

Megan Silveira gave her cellphone number to every person sheltering livestock at Pierce so they could keep in touch. “I would want that if you had my animal, which I love like my child,” she says.

Ms. Silveira has been with the ERT for over 20 years. Animals have been a constant in her life, she explains, and caring for them is her way of returning their unconditional love.

During the January wildfires, the small staff at Pierce’s equine science center worked around the clock with about 20 volunteers a day, plus officers from the county’s Department of Animal Care and Control. After the first day, Pierce was at capacity with over 200 animals.