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numbers of oligochaete worms and the amphipod, Crangonvx sp. Pool habitat diversity is consistent with last year's sampling. '- Riffle habitat diversity dropped from 2.34 to 1.22, but this may be explained by the difficulties encountered in finding a true riffle habitat for this station during the 1981 sampling. Riffle ,- habitats typically have more taxa and greater diversity than pool habitat (Haynes, 1973). Station 3 was primarily oligochaetes and chironomids in the pool habitat. Riffle habitat was dominated by these two organisms but also contained notable numbers of amphipods (Hvalella azteca) and dipterans of the family Cratopogonidae (Table 1). Diversities for this station's pool and riffle habitat were very similar to that found in 1980 (Table 2). Riffle habitat diversity values for the three most recent sampling years are noticeably higher than the 1975 diversity value, yet the 1975 and 1981 density figures and number of taxa are very similar. This is probably because a very large percentage of the total number of organisms collected in 1975 were amphipods (Harney-White Ecological Consultants, 1981). Foidel Creek None of the stations on Foidel Creek contained a flowing `- riffle habitat that could be sampled. Stations 3 and 4 were completely dry, so a Station 5 was established in a downstream beaver pond. The stability of the beaver pond habitat versus i. the intermittent stream channel is reflected in the total number of organisms being nearly thirty times higher than found in the nearby dry stream channel (Table 3). However, this high number of chironomids (44,828 out of 48,017 organisims) results in an extremely low diversity as only 3 taxa were present. Throughout all three samples collected, oligochaetes predominated and were followed in abundance by the dipteran families Chironomidae and Ceratopogonidae. Pool habitat diversities for stations 1 and 2 ranged slightly higher than previous samplings (Table 4). Number of taxa was equivalent to 1980 findings and slightly less than 1979 values. Middle Creek Stations 1 and 2 on Middle Creek provide a prime example of the lower diversity associated with a pool habitat versus an adjacent riffle habitat (Table 5). In both cases, pool habitat contained only 4 taxa versus 18 and 13 taxa for riffle samples from stations 1 and 2, respectively. This resulted in diversity values of 1.06 versus 2.71 and 2.62 for the pool versus riffle 15