Correlations Between Stream Order and Diversity of Fishes in the Blackburn Fork Drainage, Tn.

1. Correlations Between Stream Order and Diversity of Fishes in the Blackburn Fork Drainage, Tn. Michael H. Graf Undergraduate Student Fisheries Biology Concentration, Department of Biology, Tennessee Tech. Univiversity , Cookeville, TN 38505

2. Introduction • In 1957, Arthur Newell Strahler was the first person to publish a paper that defined stream size based on a hierarchy of its tributaries. • He was the person who coined the term “stream order” to classify streams.

3. Introduction • Stream Order (Strahler 1957) has been used to describe some variations in stream fish assemblages, and several authors have observed a strong association between stream order and fish species richness (Smith and Kraft 2005).

4. Introduction • As biotic and abiotic stream characteristics change from low-order headwater streams to high-order downstream locations, the distribution and abundance of fish species may also change (Matthews and Robinson 1998).

5. Diagram of Strahler’s Stream Order

6. Strahler’s Stream Order 1st order streams are headwater streams 2nd order occur at the confluence of two 1st order streams 3rd order occur at the confluence of two 2nd order streams The order can only increase if two streams of the same order intersect. Streams of lower order joining a higher order stream do not change the order of the higher stream.

7. Objective/Hypothesis • Objective – The objective of the experiment was to determine if stream order had an effect on the diversity of stream fishes. • Hypothesis – Stream order will have an effect on diversity of fish populations.

8. Method of Collection • Stream orders of 2 and 4 were used as the test, while a third order stream was used as the control. • Seining was done to sample the fish species in both the test and control streams. • For both the control and test streams, a section 100 meters (328.08 ft) long was marked off and sampled using a 10 foot (3.048 meter) seine.

9. Materials • 10 Foot (3.048 meter) seine • 5 Gallon (18.93 liter) buckets • Dip Net • Marking tape • Tape measure • Dichotomous Key (Fishes of Tennessee by Etnier and Starnes) • Data Form

10. Third Order Sample Site • The control stream location was where Gainsboro Grade crosses the Blackburn Fork.

11. Fourth Order Sample Site • This site is where Cummings Mill Rd. crosses the Blackburn Fork. • It is a Fourth order stream that I used as test.

12. Second Order Sample Site • This is the Second Order test location. • It is located where Gainsboro Grade crosses Little Creek

13. First Order Stream(Location not sampled)

14. Results • The table below lists the species that were detected at the sample sites and the overall richness. • The site with the greatest diversity was the third order stream, with a total of nine species found. • I failed to accept the hypothesis,

15. Discussion • There could be a number of reasons the results did not prove the hypothesis. • The local habitat of the three locations varied greatly between the sides and was probably of much more significance that the order of the stream.

16. Discussion • The third order most definitely had the most suitable habitat for fish when compared to the other two sites. The amount of physical structure is closely related to the abundance of certain species of fish (Orth and White 1999). The complexity of physical habitats is often correlated with diversity of fishes and resilience of fish assemblages (Pearsons et al. 1992). This site had the most structure such as submerged tree limbs, boulders, and root wads along the bank, which may account for why it had the highest diversity. It may have also had the most suitable spawning habitat. Many stream fish spawn over or in rock material of special sizes (Shirvell and Dungey 1983).

17. Discussion • The fourth order site was mostly open bedrock and shallow gravel bars, with very little structure. • The second order site had the highest amount of sedimentation, which may explain why it had the least species richness.

18. Discussion • Landscape attributes are often successful predictions of broad patterns of fish assemblages at large spatial extents but may fail under specific circumstances (Smith and Kraft 2005). • Fish assemblages are clearly influenced at small scales by local biotic and abiotic factors (Jackson et al. 2001). • The sites of my research may not be a fair and true representation of the entire watershed.

19. Conclusions • The stream order of the three locations did not seem have as much effect as the local habitat factors. The characteristics of the streams were very different. In order to make a correlation between stream order and the diversity of fish assemblages, the study would need to be broadened to include as many habitat types as possible within each stream order.

20. Literature Cited • Bowlby, J. L. , and J. C. Roff. 1996. Trout biomass and habitat relationships in southern Ontario, Canada, streams. Transactions of the American Fisheries Society 115: 503-514. • Gorman, O. T. 1986. Assemblage organization of stream fishes: the effect of adventitious streams. The American Naturalist 128: 611-616. • Jackson, D. A., P. R. Peres Neto, and J. D. Olden. 2001. What controls who is where in freshwater fish assemblages: the roles of biotic, a biotic, and spatial factors. Canadian Journal of Fisheries a nd Aquatic Sciences 58: 157-170. • Matthews, W. J., and H. W. Robinson. 1998. Influence of drainage connectivity, drainage area, and regional s pecies richness on fishes of the interior highlands in Arkansas. American Midland Naturalist 139: 1-19 • Orth, D. J., and R. J. White. 1999. Stream Habitat Management. Pages 249-281 in C. C. Kohler and W. A. Hubert, editors. Inland Fisheries Management in North America, 2nd edition. American Fisheries Society, Bethesda, Maryland. • Pearsons, T. N., H. W. Li, and G. A. Lamberti. 1992. Influence of habitat complexity on resistance to flooding and resilience of stream fish assemblages. Transactions of the American Fisheries Society 121: 427-436. • Poff, N. L. 1997. Landscape filters and species traits: towards mechanistic understanding and prediction in stream ecology. Journal of the North American Benthological Society 16: 134-145. • Smith, T. A., and C. E. Kraft. 2005. Stream Fish Assemblages in Relation to Landscape Position and Local Habitat Variables. Transactions of the American Fisheries Society 134: 430-440. • Shirvell, C. S. and R. G. Dungey. 1983. Microhabitats chosen by brown trout for feeding and spawning in rivers. Transactions of the American Fisheries Society 112: 355-367. • Strahler, A. N. 1957. Dynamic basis of geomorphology. Geological Society of America Bulletin, 63, 923 – 938.

21. Poster

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