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Yellow perch spawning and egg deposition survey in Lake Michigan waters near Green Can Reef, Milwaukee - 2007

Yellow perch spawning assessment, Green Can Reef – 2007  

In 2007 sampling year, we sampled spawning yellow perch three times with a total effort of 2,000 ft of gillnet. The mesh sizes used were 2”, 2.5”, 2.75”, 3” and 3.25”. Sampling was conducted on 5/22/07, 5/30/07 and 6/5/06. A total of 2,132 yellow perch were captured, of which only 3% were females. As part of the Yellow Perch Task Group lake-wide spring assessment protocol we added a 2” mesh 100-foot monofilament panel to each box which probably contributed to increased number of males. We also collected expanded age samples taken from each 10mm size increment (5 males and 5 females in each size-class). The bottom temperature was 47 0F at 32’ on 5/22/07, and 44 0F on 5/30/07 at 54’. Most females captured on 6/5/07 were spent. The 1998 year-class comprised only 35% of the spawning population in 2007, which was closely followed by the 2002 year-class perch (32%). Age 4 yellow perch from 2003 year-class also made up a large portion (17%) of the spawning population.

2007 – Yellow Perch Egg Deposition Survey:

The WDNR dive team continued the effort using the protocol similar to 2003 to quantify egg deposition in the Green Can Reef area.

 Total area searched = 34,960m²

Total eggs found = 378

Egg masses per 1000 m² = 10.81