Questions are good; that is one way we learn.
Egg laying for yellow perch is determined by water temperature and day length. Usually water temperature is more of a factor than day length, but it is sometimes variable depending on the strain of perch and water conditions. More southern adapted perch will lay eggs earlier compared to northern perch, and in these cases, it seems to be dependant a lot on temperature since day length is similar in AK & MO compared to OH, IN and Ontario. Perch in coolder Lake Erie lay eggs about 3-4 weeks later compared to perch egg laying in ponds in northern Ohio even though day length is the same for both areas.
It seems to me that it takes a certain amount of degree days after ice cover (39F 4C) for perch to finish egg development before eggs are 'ready' to be laid. There seems to always be a few very early and a few late spawners. However the major egg laying sessions occur mid way between the earlest and latest spawns. This probably evolved so all eggs are not a laid within a short time span to lengthen the hatch time to better take advantage of the formation of the developing plankton bloom which occurs above 50F-55F and feeds the perch fry.
Generally don't expect to see any perch eggs until the water temps get to and stabalize at 48F. Often eggs don't appear until water temps are 50F at one foot deep. The egg ribbons that I see first are always in water 8" to 16" deep and near shore among old plant stems or on shoreline brush-branches. Dark bottom areas will absorb more radiant heat and in cold water perch will seek these areas for laying eggs.
I don't see much perch feeding activity on surface pellets until the water is 50F(10C). This usually co-incides with early egg laying. Newly spent males & especially females have strong urges to start eating again and building fat reserves. Last night when water was 51F(10.6C) was the first that I saw some but not a lot of good surface feeding on pellet and sinking pellets were also fed. Many of the perch were still gravid. Prior to this (45F-48F - 7.2C-8.9C) about all pellet feeding activity was subsurface on soft sinking pellets which were readily eaten and they were very hesitant to surface feed. This was probably because the feeding fish were getting food subsurface, thus why surface feed?
Minnows will also probably stay deeper out of sight until the water gets near 50F, 10C. Sometimes the perch will feed fairly heavily on slow moving minnows (fatheads) during winter and significantly decrease the number of minnows especially those 1"-1.7" long, leaving mostly the larger breeders until most all the small ones are consumed.
Last edited by Bill Cody; 04/08/13 07:51 PM.
