A Scud is an extremely tiny shrimp like creature the males of which are barely an 1/8th inch long. As for whether you have them up North or not I couldn't say. Perhaps keith_r could tell you since he's up in that direction. They are great in a filtration system for breaking down the particulates etc and the fish love them when they can get to them. They also produce fry or baby shrimp by the millions during the spring and summer which helps to feed (fish) fry in outdoor ponds or pools. Too bad they don't get big enough to eat, I'd never go hungry for something to eat

Below is baby Scuds in the making. Photo courtesy of Stucco