Fishhead :

You are correct climate/growing season/latitude has a MAJOR effect on ponds and fish. I tried to factor that into the answer above. For example LMB down here at one year and 10in. spawn. From what I have read it often takes 2 yrs. up north. On the seine surveys we can do those now so I added a mth for you. A mth to six weeks after your LMB spawn is a good time and even later will work as well. Find the shallow area of the pond and make 30ft sweeps with the net. One end stays at waters edge. Walk out the other end into the pond and swing it in a quarter circle and pull it out and count the fish (as per the chart). Then gently flip the net over and back in the water ( or back it out into the pond) to release the fish. I use a 30 ft by 4 ft 1/4in mesh minnow seine that I got at Wal-Mart for $ 20.