How can you have a fishery…

How can you have a fishery to the south (Rainy) with a 35 - 45 cm slot and one to the north with a 35 - 45 cm slot (Winnipeg River) and the one in the middle is different!!!!??? And yet all 3 are part of the same watershed/body and are all part of the same fishery. What a joke! And people can still keep a trophy fish! Another joke! I'm all in support of a reg change, but do it to help the fish populatiom not appease American anglers and tourists and tournament organizers.