Scott, do you know if they were true mudpuppies, or just larvae of tiger or spotted salamanders. Mudpuppies are larger and brown with wrinkly skin. If they were just larvae, they would have transformed, left the pond for a year or two then returned to spawn leaving you with plenty of offspring to find. I have a pond where we aluminum sulfate and this brings the tiger salamander up to the surface. Pretty cool. I also have an 11 inch tiger with two smaller ones in a tank in the garage. The kids (and I) love to feed them.
Robert B