Table 1.

SIMPER comparing community composition between sites above and below the discharge during the two sample periods following the discharge event (August and September 1) in 2011. Average dissimilarity between upstream and downstream areas = 52.87%

Species	Family	Above Discharge	Below Discharge	Avg. Diss	Diss./SD	Contrib. %	Cum. %
		Avg. Abundance	Avg. Abundance
Hybognathus nuchalis	Cyprinidae	6.02	2.63	11.21	1.32	21.21	21.21
Cyprinella venusta	Cyprinidae	6.03	5.12	7.43	1.69	14.04	35.25
Ammocrypta beani	Percidae	2.40	0.16	6.26	1.52	11.83	47.09
Gambusia affinis	Poeciliidae	0.43	1.95	4.54	0.89	8.58	55.67
Pimephales vigilax	Cyprinidae	1.32	0.80	3.10	1.31	5.86	61.52
Notropis longirostris	Cyprinidae	1.85	1.59	3.04	1.24	5.75	67.28
Notropis texanus	Cyprinidae	1.25	0.56	3.03	1.10	5.74	73.02
Lepomis megalotis	Centrarchidae	0.70	0.96	2.77	1.18	5.24	78.26
Dorosoma petenense	Clupeidae	0.43	1.31	2.72	0.61	5.14	83.40
Notropis atherinoides	Cyprinidae	0.87	0.20	2.23	0.95	4.21	87.61
Labidesthes sicculus	Atherinopsidae	0.52	0.41	1.72	0.83	3.26	90.86