Abundance and habitat use of juvenile sunfish among different macrophyte stands

Figures & data

Figure 1 Monthly mean Lepomis densities (± 1 SE) among 3 habitat types (open water, American pondweed stands, and Eurasian watermilfoil stands) in Cedar Lake.

Figure 2 Length frequency distribution of juvenile bluegills sampled among 3 habitats (open water, American pondweed stands, and Eurasian watermilfoil stands) in Cedar Lake. Distributions were significantly different among all habitat types (Kolmogorov-Smirnov 2-Sample Test; α^″ = 0.016).

Table 1 Strauss' linear selectivity indices (L) of juvenile sunfish for vegetation-associated invertebrates in Cedar Lake. Positive L values indicate a preference for a taxon, whereas negative L values indicate a lack of preference for a taxon; N refers to the number of individuals in which the taxon was present in the sunfish diets. For each species, the number of individuals processed for diet is indicated in parentheses next to the species name.

	Diet selectivity
	Bluegill	(n = 137)	Green	(n = 25)	Longear	(n = 62)	Redear	(n = 35)
Taxon	N	Mean L	N	Mean L	N	Mean L	N	Mean L
Amphipoda	31	0.040	12	0.065	23	0.052	7	0.136
Cladocera	113	−0.214	21	−0.325	53	−0.359	21	−0.436
Copepoda	101	0.010	22	0.010	49	0.003	19	0.010
Diptera	133	0.227	21	0.027	61	0.209	33	0.070
Ephemeroptera	33	0.054	14	0.134	29	0.056	7	0.120
Gastropoda	16	0.052	6	0.037	13	0.078	29	0.294
Ostracoda	118	0.114	23	0.163	56	0.192	28	0.291
Trichoptera	6	0.039	15	0.112	33	0.036	7	0.070

Figure 3 Monthly mean stem density (± 1 SE) of American pondweed and Eurasian watermilfoil stands in Cedar Lake.

Figure 4 Monthly mean invertebrate density (± 1 SE) per stem within American pondweed stands and Eurasian watermilfoil stands in Cedar Lake.

Figure 5 Interaction between Lepomis density (± 1 SE) within vegetated habitats and water level data in Cedar Lake. Normal pool level for Cedar Lake is indicated with a dashed line.