A huge reason for overpopulation is dogs not being neutered: "The measure encourages both dog licensing and neutering. Included in the measure is a new requirement on groups or organizations that sell dogs or put them up for adoption that any dog released must be neutered." "And owners would have a slight incentive for neutering: the license fee would be $16 for neutered dogs, $40 for those that are not." City Council Committee OKs New Philadelphia Dog Laws « CBS Philly