Hi HL Chilly,
Many people here may not know what you mean by 'pariah' dogs, as it isn't a commonly used term. The local term for the Belizean crossbreeds you see around is 'potlicker'.
There is a wonderful little humane society in San Pedro called SAGA Humane Society. They do a hard job against many challenges but have so many wonderful rescue stories. If you'd like to find out more about their work - Saga Humane Society web page.
There are laws related to stray dogs and cruelty. SAGA Humane Society works closely with the Town Board and Public Health to address these issues.
Anyone who has been traveling to San Pedro over the years can attest that SAGA has made a huge impact on the stray population in San Pedro and provide many important services to the community. They receive no government funding and rely on donations to do their work. Check out their website and if you can, please help them with a donation.