Proceedings of the Oklahoma Academy of Science

The Tall Grass Prairie Preserve was established by the Nature Conservancy in 1989. This land is located in Osage County of north-central Oklahoma and currently includes 30,000 acres (12,000 ha). Previously, the land was grazed by cattle, and some oil field activity presently occurs. This study focuses on the aquatic macroinvertebrate community inhabiting the Sand Creek stream ecosystem which drains the area.

Aquatic macroinvertebrate communities are often studied in conjunction with stream investigations. Frequently these studies are conducted to determine species composition of a stream or its drainage basin. Several such investigations have taken place in Oklahoma (1-13). However, there have been no such efforts in the Sand Creek drainage basin of the Tall Grass Prairie Preserve.

Benthic macroinvertebrate communities have also served as indicators of water quality in streams (14-18). Characteristics of macrobenthic organisms which makes them especially useful for water quality studies include: 1) long life cycles which may reflect conditions for an extended period of time; 2) low motility; 3) various ranges of tolerance to varying environmental conditions; and 4) occupancy of central positions in aquatic food chains (19).

Species diversity indices have been used to analyze community structure of benthic macroinvertebrates. Shannon's diversity index (d) (20) is possibly the most widely accepted as it reflects the eveness of taxa distribution, is dimensionless, and is relatively independent of sample size (16). Other studies have shown the usefulness of Shannon's diversity index (17,18,21). Sorenson's index of similarity (22) has been used to compare faunal similarity between sampling sites (18).

The objectives of this investigation were to: 1) determine the taxonomic composition and relative abundance of the macroinvertebrate community; 2) establish seasonal trends occurring in the macroinvertebrate community; and 3) provide baseline water quality data, based on macroinvertebrates and several physicochemical measurements, to better understand and manage the watershed of the Sand Creek drainage basin.

METHODS

Macroinvertebrate communities in the Sand Creek drainage basin were investigated for an annual period. Six sampling sites were established (Figure 1) and visited bimonthly: May, July, September, November, January, and March. Four quantitative samples were collected at each site during each collection using a Surber net. Qualitative

{Page 4}

collections were also made by examining rocks, wood debris, leaf debris, and other microhabitats by hand in the stream for 45 minutes at each sampling site during May and December. This has been demonstrated to be an effective sampling method in combination with traditional sampling equipment (23), especially in streams such as these which contain a diversity of microhabitats.

All invertebrate collections were preserved in the field and returned to the laboratory for sorting, identification, and enumeration. Statistical analysis, including a modification of Shannon's diversity index (16,24) and community similarity (22) were determined.

Physicochemical conditions at each station were also monitored during each collection period. These parameters included water temperature (Celsius thermometer), dissolved oxygen concentration (Winkler method), pH (pocket pH meter), and conductivity (conductivity meter).

RESULTS and DISCUSSION

Ranges of the physicochemical parameters are listed in Table 1. The minimum water temperature recorded, 2 °C, occurred during January at site 6 while the maximum water temperature observed, 35 °C, occurred during July at site 3. Minimum dissolved oxygen concentration, 5.0 mg/l, was recorded from site 5 during July and maximum dissolved oxygen concentration, 9.9 mg/1, occurred at site 3 during January. The pH ranged from 7.0 at site 3 in January to 8.3 at site 1 in March. Conductivity varied from a low of 285 µS/cm at site 2 in September to a high of 520 µS/cm at site 2 in January. These results, especially water temperature and dissolved oxygen concentration, seem more related to differences between seasons than to differences between sites. Usually the variation among sites sampled at a given time was less than that for a given site sampled at different times. Generally, these values were within ranges expected in this

{Page 5}

region of Oklahoma (25) and indicate conditions capable of supporting a diverse biota (26).

A total of 9010 individuals representing 134 taxa were encountered during this study (Table 2, page 7). In terms of both number of individuals and number of taxa, insects were dominant.

More individuals were collected annually from sites 3 and 4 than at other sites (Table 2 [Page 7, Page 8, Page 9]). However, this may be misleading since more collections actually occurred at sites 3 and 4. A more accurate view may be to observe the number of individuals collected per sample annually. When viewed in this manner site 6 contained the highest number of individuals, probably because it was further downstream where more nutrients may have been present and conditions were generally more stable (27). The fewest individuals collected per sample was at site 4. This was expected since this site experienced stressful conditions (higher conductivity values (Table 1) and reduced flow) during part of the study period. Regarding the number of taxa collected over the annual period, sites 2 and 5 showed the highest numbers. This may be due to the presence of larger amounts of microhabitat in confined areas at the sampling sites (23,28).

Annual species diversity values (Table 3) were high at all sampling sites. This usually indicates that good water quality and a healthy aquatic environment exist in the streams (16). A general pattern emerges when the species diversity at each site for each collection is observed. These values were lowest in July and mostly increased following the summer months through the autumn, winter, and spring. The depressed diversity values in July may have been due to emergence of adults or the occurrence of higher temperatures limiting some species (28).

Similarity analysis (Table 4) revealed that the greatest similarity occurred between sites 2 and 3 and the least similarity between sites 1 and 5. Sites 2 and 3 were located near each other and possessed similar substrates, an important factor to aquatic invertebrates. Sites 1 and 5 were far apart and had very different physical conditions; the presence of different taxa is not surprising.

A great diversity of aquatic macroinvertebrates was present in these streams. Dominant taxa included the oligochaete Limnodrilus, the mayflies Baetis and Caenis, and the chironomids Dicrotendipes and Orthocladius. These taxa were present at all stations during most collections. Other common taxa included Nais, Physa, Stenonema, Enallagma, Sialis, Stenelmis, Bezzia, Cladotanytarsus, Cricotopus bicinctus, Endochironomus, Microtendipes pedellus, Polypedilum halterale, Procladius, and Tanytarsus. Aquatic insects, especially the dipterans, were the most abundant major group (Table 2 [Page 7, Page 8, Page 9]).

The chironomid Fittkauimyia is reported for the first time in North America outside of Florida. Ninety-three larvae of this genus were collected among decaying leaves in pools at sites 5 and 6 during November.

Overall, the water quality of these streams was generally high. This may be illustrated by the high species diversity, the presence of many pollution-intolerant macroinvertebrates, and the fact that aquatic insects were so much more prevalent than oligochaetes.

ACKNOWLEDGMENTS

The author thanks Caryn Vaughn for providing logistical assistance and Vince Walker for help in the field. This project was funded by the Oklahoma Natural Heritage Inventory in cooperation with the Nature Conservancy. The University of Central Oklahoma provided released time to conduct this research.

REFERENCES

1. Harrel, R.C., Benthic invertebrates of the Otter Creek drainage basin, northcentral Oklahoma. Southw. Nat. 14, 231-248 (1969).

2. McKinley, R.E., Prins, R. and Jech, L.E., Occurrence and distribution of arthropods in Platt National Park, Murray County, Oklahoma. Proc. Okla. Acad. Sci. 52, 49-52 (1972).

3. Reisen, W.K., The ecology of Honey Creek, Oklahoma: Spatial and temporal distributions of

{Page 6}

the macroinvertebrates. Proc. Okla. Acad. Sci. 55, 25-31 (1975).

4. Morris, W.K. and Madden, M.P., Benthic macroinvertebrates communities and water quality evaluation of the Washita River. Proc. Okla. Acad. Sci. 58, 93-97 (1978).

5. Wilhm, J.L., Cooper, J. and Burks, S., Species composition of algae and benthic macroinvertebrates in the Blue and Kiamichi Rivers. Proc. Okla. Acad. Sci. 59, 85-88 (1979).

6. Margraf, F.J. and Plitt, D.W., The aquatic fauna and water quality of Cottonwood Creek, Oklahoma. Proc. Okla. Acad. Sci. 62, 1-6 (1982).

7. Orth, D.J., Jones, R.N. and Maughan, O.E., Species composition and relative abundance of benthic macroinvertebrates in Glover Creek, southeast Oklahoma. Proc. Okla. Acad. Sci. 62, 18-21 (1982).

8. Cheper, N., Survey of aquatic invertebrates of south-central Oklahoma. I. Lotic animals. Proc. Okla. Acad. Sci. 65, 35-37 (1985).

9. Gore, J.A. and Bryant, R.M., Changes in fish and benthic macroinvertebrate assemblages along the impounded Arkansas River. J. Freshw. Ecol. 3, 333-345 (1986).

10. Bass, D., A survey of aquatic invertebrates from the Wichita Mountain streams. Proc. Okla. Acad. Sci. 70, 35-36 (1990).

11. Hoover, J.J., Larval midges (Diptera: Chironomidae) from northeastern Oklahoma. Proc. Okla. Acad. Sci. 70, 39-40 (1990).

12. Bryant, R., and Wilhm, J., Species diversity of benthic macroinvertebrates in Salt Creek, Oklahoma. Proc. Okla. Acad. Sci. 70, 9-12 (1990).

13. Bass, D., and Walker, V., A preliminary report of invertebrates from hyporheic sediments of the North Canadian River. Proc. Okla. Acad. Sci. 72, 3-4(1992).

14. Gaufin, A.R., and Tarzwell, C.M., Aquatic invertebrates as indicators of stream pollution. Pub. Health Rep. 67, 57-64 (1952).

15. Wilhm, J.L, and Dorris, T.C., Species diversity of benthic macroinvertebrates in a stream receiving domestic and oil refinery effluents. Am. Midl. Nat. 76, 427-449 (1966).

16. Wilhm, J.L. and Dorris, T.C., Biological parameters for quality criteria. Bioscience 18, 477-481 (1968).

17. Harrel, R.C., and Dorris, T.C., Stream order, morphometry, physico-chemical conditions, and community structure of benthic macroinvertebrates in an intermittent stream system. Am. Midl. Nat. 80, 220-251 (1968).

18. Bass, D., and Harrel, R.C., Water quality of a southeast Texas stream. Hydrobiologia 76, 69-79 (1980).

19. Keup, L.E., Ingram, W.M., and MacKenthum, K.M., The role of bottom-dwelling macrofauna in water pollution investigations. US Dept. of Health, Educ., and Welfare, Cincinnati, Ohio. (1966) 23 pp.

20. Shannon, C.E., A mathematical theory of communication. Bell Syst. Tech. J. 27, 379-434, 623-656 (1948).

21. Harrel, R.C., and Duplechin, J.L., Stream bottom organisms as indicators of ecological change. Texas A&M Univ. OWRR Project B-189-TEX. (1976) 49 pp.

22. Sorenson, T., A method of establishing groups of equal amplitude in a plant society based on similarity of species content. K. Danske Vidensk. Selsk. 5, 1-34 (1948).

23. Bass, D., Habitat ecology of chironomid larvae of the Big Thicket streams. Hydrobiologia 134, 29-41 (1986).

24. Patten, B.C., Species diversity in net phytoplankton of Raritan Bay. J. Mar. Res. 20, 57-75 (1962).

25. Blazs, R.L., Walters, D.M., Coffey, T.E., White, D.K., and Boyle, D.L., Water resources data for Oklahoma. United States Geological Survey Rep. No. USGS/WRD/HD-91/303 (1991) 517 pp.

26. American Public Health Association, Standard Methods for the Examination of Water and Wastewater, 16th ed. American Public Health Association, Washington, D.C. (1985) 1268 pp.

27. Vanote, R.L., Minshall, G.W., Cummins, K.W., Sedell, J.R., and Cushing, C.E., The river continuum concept. Canad. J. Fish. Aquat. Sci. 37, 130-137 (1980).

28. Hynes, H.B.N., The Ecology of Running Waters. Univ. Toronto Press, Toronto (1970) 555 pp.