Pond Boss Forums INTRO Questions & Observations Northern BG: Multiple Spawns or just Rolling Spawn

Thanks for posting that picture, Theo!

We have been trawling (small mesh surface trawl) for larval bluegills in some SD and NE waters for several years. We have to add a fourth option to Theo's list: among-year differences.

We track both catches (number per water volume) of newly hatched bluegill larvae and then we [well, not we -- the students have to do the work :)] pull the otoliths and estimate hatching dates.

In both our SD and NE waters, we have years with what appear to be clear, multiple spawns. The most we have found is three spawns. Other years, in the same waters, we find only a single "peak" in larval abundance, indicating one primary spawn or a rolling spawn. Usually, we think of the rolling spawn idea, as we get low numbers of larvae before and after that big peak.

Moderator's note: That was Shorty's pic.