Does your organization post their pets on the AdoptAPet website? If so, you can also post volunteer opportunities on that site. For example, I just searched for volunteer opportunities in a 35 mile radius from my location and see 16 opportunities from different rescue and shelter organizations. You can post a variety of volunteer jobs and get notified when someone says they're interested. When we ran our own foster-based adoption program a few years ago, we used this feature.
I've attached a screenshot of my Volunteer Opportunities search in AdoptAPet.
You can also post volunteer opportunities at VolunteerMatch: https://www.volunteermatch.org/nonprofits/ . I've attached a screenshot of their "Animal" opportunities near me so you can see what they look like.
Both of these options are free and can help recruit volunteers in a specific area. Good luck!
#PeopleManagement