not enough info given, but after googling "mass" "ymca" and "pond", i take it you mean Mill pond? I've never fished there, but off the map image, it looks to be pretty small. I'm sure there are sunfish, perch, and largemouth bass...possibly some pickerel. Thats pretty much your run of the mill standard. There may be sucker fish, carp, and catfish too. Just my 2 cents 
