Post a description and where you found the animal on pawboost, nextdoor, facebook & craigslist. You can also give a heads up to your local animal control and animal shelter with your info. This is where people start looking when their pet takes a walk or doesn't come home.
Take the pet to the closest animal shelter and most vets, they'll be able to scan a chip (if the animal has one) to find the owner. Otherwise, Facebook and other social media is a great way to find owners
Most likely the pet will be put in stray hold for a matter of time before it can be adopted. Yet, if the pet has any contact information or a micro chip they might be able to get ahold of the pet owner :) hope this helped
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