You will not find Cock fighting on an online betting sites because this sports is not popular and is limited to very small population / people of the world. Mostly the gamblers who bet on this cock betting are traditional gamblers who manually bet on these fights. In most places it is illegal and be considered as an abuse of animals. Many NGOs may consider these fights as violation of rights of the animals.
They already said there is, they do have a website. I think there are more of it. Quite not a common gambling game for all but looks fun to watch. It will only be illegal when money involve needs to be taxed by the government. Animal welfare should also try checking spiders fighting, they fight to death like the cocks stabbing knives.
Do you have the name of that site ? I am sure it would be a local gambling site and will be interesting to know how they bet on it.
Do they have tournaments on it or it is a betting on an individual cock? There must be name of the cocks mentioned too
I think it was this one http://sabongboss.com I don't remember the other one but they probably restrict google bots to index the website. When someone search for it on google, It doesn't come up in the search results but you may try googling it more "e-sabong" is what they call it. This is a common hobby by Filipinos and Indonesians.
