Agree about offering low or no cost spay and neuter — and also insist that shelter directors become marketing agents. Marketing animals for adoption is no different from marketing in a business: the public must know what you have and you have to have hours that make it easy for the public to come by. Most shelter directors do not do that. They collect a check and when they have more animals than space, kill. Volunteers need to be recruited and used to the maximum: calling rescues, local no-kills, fosters, etc... Set up fosters and put out a call to the public that fosters and homes are needed — on radio, television, direct mail — you name it. Go to those who hold the purse strings and beg. If that doesn’t work, make it public that you need funds. Off-site adoptions, adoption fairs, anything and everything to get the animals into home. There are THOUSANDS of things which shelters can do to stop the killing. Most are not being done, so before pointing fingers at the public, those in charge need to look closely in the mirror first. (First step has to be taking killing off the table as an option. Just like “divorce” in a marriage as long as it’s there, it’ll be used. Once it’s no longer allowed, marketing and adoption become the ONLY options and rolling up the sleeves and working like there’s no tomorrow to make it happen are the only things one can do because the choices are now only about life.)
Many shelters are doing everything you’ve mentioned. Mine does and they still get overflows. The things that really hammer them are hoarders, ferals (which they have a spay program for) and abandoned animals. It is surprising the number of animals that are coming in because they’ve been left in an empty apartment or house.
The other thing that makes my shelters’ numbers go up are because the “no kill” shelters around here only take certain animals and have less room than other shelters, so they pass the rest onto other shelters. They get to claim they’re no kill but they don’t accept all animals, and most have nowhere else to go but our shelter. It’s really a bogus claim that most “no kill” shelters claim. They take only the best animals and most others are sent to other places and they wind up with excess numbers.
The blame lays heavily on the public and breeders. People would not be surrendering their animals if they didn’t buy them in the first place. Most of these people surrender them because they bought the animal on impulse and have no idea what’s required to take care of it. Shelters would not have to deal with massive numbers of animals in bad shape if hoarders were dealt with properly and allowed to continue hoarding. Breeders keep pumping out supply when supply is already excess and perfectly good adoptable animals could be adopted instead.