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Chemical Reclamation -- A USFWS Biological Opinion and a Finding of No Significant Impact determined that reclamations could occur year round without adverse affect to listed species (USFWS 1998b, USFWS 1998c). Sixty-nine ponds were chemically reclaimed with rotenone (66 ponds), chlorine (2 ponds), or both (1 pond - winter application of chlorine resulted in an incomplete fish kill, rotenone was then used the following summer and a complete fish kill was obtained). Chlorine was used instead of rotenone for winter reclamations because rotenone toxicity is diminished in colder water temperatures (Spitler 1986). Another pond reclamation using chlorine was not successful and resulted in an incomplete fish kill. Like the pond described above that was treated with chlorine and rotenone, this pond was treated a second time with chlorine and all fish were removed. An attempt was also made to induce a summer kill by applying an herbicide to ultimately create an oxygen deficit in the water column of two densely vegetated ponds. This was unsuccessful in both cases and rotenone was later applied. Endangered fish mortality was not observed following these 69 reclamations. Re-invasion - In the 71 ponds where fish were removed, the most common fishes in terms of incidence (number of ponds containing species) were green sunfish, common carp, largemouth bass, and black bullhead (Table 13). Of the 71 ponds, 54 were later re-sampled to determine incidence of re-invasion. Of these 54 ponds, 35 (65%) had re-invaded with nonnative fish and two of the 35 also contained native fish. Some of the 35 ponds were sampled within three months of treatment and had re-invaded, while re-invasion of others occurred within 37 months post-reclamation (Table 14). However, the exact time of re- invasion for each of the 35 ponds is unknown. Re-invasion may have occurred immediately following detoxification of reclaimed ponds or just prior to re- sampling. Green sunfish and fathead minnow were present in 26 (74%) and 13 (37%), respectively, of the 35 re-invaded ponds (Table 15). Largemouth bass were only sampled in two of the 35 re-invaded ponds but were present in 28 of the 54 re-sampled ponds prior to treatment. Additional nonnative fish species that re- invaded one or more of the 35 ponds included common carp, goldfish, sand shiner, white sucker, black bullhead, and mosquitofish (Table 15). Nonnative fish 31