Does the morphological index suggest shrinkage over  winter?            
       (e.g. Shin & Nicol, 2002)
0
0.5
1
1.5
2
2.5
3
3.5
5
15
25
35
45
55
65
Total length (mm)
Eye diameter (mm)
Fall 2002 (n=656)
Winter 2001 (n=587)
Winter 2002 (n=184) Daly
winter
fall
Eye size vs total length (mm) of field-collected E.superba