Shorty :

Did a little research to add to my experiences. Hear is some info. I have encountered LMB spawning late (Sept small yoy) twice. Once I am fairly sure it was not a second spawn the other who knows. Both resulted in small LMB in the fall. Others I know insist that LMB can and have spawned twice in their ponds. I can't say that is true or disprove it either.

The first time was when I added some late maturing 10 inch LMB to a pond. Those fish were right from the hatchery (had not ever spawned) and were the product of a prior July spawn at the hatchery. They were held over the winter for me at the hatchery until they were 10 inches and were placed in the pond in mid July and spawned in Aug. I saw a few nesting and about 3 weeks later saw some small LMB yoy. I classify this event as due to fish condition. They were not mature enough when the regular spawn conditions occurred in April so they waited.

The other time I encountered a late LMB spawn was in a oxbow lake that is subject to river/resv. influence. In that case the conditions for the spawn were right in May (subject to cold resv. tailrace water) when big rains muddied the water and caused the resv. to be opened for flood avoidance purposes. The water went up 20 feet and was muddy and cold for 2 mths. From what I could tell the LMB in May stopped spawning and delayed until conditions were right in late July then spawned. I assume any fish that spawned in May lost the brood and started over and those who hadn't spawned delayed. Maybe a mix of both. I classify this event as due to water conditions.

Here are a few ideas from some research. Many things can effect the LMB spawn including , weather , water conditions , temps. , fish condition , spawn suppression by other fish (BG ,GShad , or a stunted combo of forage fish), and others. If any of these conditions are present then the LMB may delay spawning until the condition is gone ( as long as the temp. and photoperiod window is open) or may reabsorb the eggs and produce them later when conditions improve. I guess this could happen in mid spawn and you might end up with 2 distinct spawns or if conditions did not improve then you might miss a year class altogether. I suspect that most times people encounter small yoy LMB in fall it is due to spawn suppression and not due to 2 spawns. Look at the thread linked in my post above about spawn duration and keep in mind that you can have several different sizes of LMB yoy due to rolling spawn. Any other comments would be welcome. \:\)