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

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. 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. He was the person who coined the term “stream order” to classify streams.

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). 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).

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). 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).

Diagram of Strahler’s Stream Order

Strahler’s Stream Order 1 st order streams are headwater streams 2 nd order occur at the confluence of two 1 st order streams 3 rd order occur at the confluence of two 2 nd 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.

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

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

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 Data Form

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

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.

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

First Order Stream (Location not sampled)

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

Discussion There could be a number of reasons the results did not prove the hypothesis. 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. 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.

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). 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).

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

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). 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). 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. The sites of my research may not be a fair and true representation of the entire watershed.

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. 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.

Literature Cited Bowlby, J. L., and J. C. Roff Trout biomass and habitat relationships in southern Ontario, Canada, streams. Transactions of the American Fisheries Society 115: Bowlby, J. L., and J. C. Roff Trout biomass and habitat relationships in southern Ontario, Canada, streams. Transactions of the American Fisheries Society 115: Gorman, O. T Assemblage organization of stream fishes: the effect of adventitious streams. The American Naturalist 128: Gorman, O. T Assemblage organization of stream fishes: the effect of adventitious streams. The American Naturalist 128: Jackson, D. A., P. R. Peres Neto, and J. D. Olden What controls who is where in freshwater fish assemblages: the roles of biotic, a biotic, and spatial factors. Canadian Journal of Fisheries and Aquatic Sciences 58: Jackson, D. A., P. R. Peres Neto, and J. D. Olden What controls who is where in freshwater fish assemblages: the roles of biotic, a biotic, and spatial factors. Canadian Journal of Fisheries and Aquatic Sciences 58: Matthews, W. J., and H. W. Robinson 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 Matthews, W. J., and H. W. Robinson 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 Stream Habitat Management. Pages in C. C. Kohler and W. A. Hubert, editors. Inland Fisheries Management in North America, 2nd edition. American Fisheries Society, Bethesda, Maryland. Orth, D. J., and R. J. White Stream Habitat Management. Pages 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 Influence of habitat complexity on resistance to flooding and resilience of stream fish assemblages. Transactions of the American Fisheries Society 121: Pearsons, T. N., H. W. Li, and G. A. Lamberti Influence of habitat complexity on resistance to flooding and resilience of stream fish assemblages. Transactions of the American Fisheries Society 121: Poff, N. L Landscape filters and species traits: towards mechanistic understanding and prediction in stream ecology. Journal of the North American Benthological Society 16: Poff, N. L Landscape filters and species traits: towards mechanistic understanding and prediction in stream ecology. Journal of the North American Benthological Society 16: Smith, T. A., and C. E. Kraft Stream Fish Assemblages in Relation to Landscape Position and Local Habitat Variables. Transactions of the American Fisheries Society 134: Smith, T. A., and C. E. Kraft Stream Fish Assemblages in Relation to Landscape Position and Local Habitat Variables. Transactions of the American Fisheries Society 134: Shirvell, C. S. and R. G. Dungey Microhabitats chosen by brown trout for feeding and spawning in rivers. Transactions of the American Fisheries Society 112: Shirvell, C. S. and R. G. Dungey Microhabitats chosen by brown trout for feeding and spawning in rivers. Transactions of the American Fisheries Society 112: Strahler, A. N Dynamic basis of geomorphology. Geological Society of America Bulletin, 63, 923 – 938. Strahler, A. N Dynamic basis of geomorphology. Geological Society of America Bulletin, 63, 923 – 938.

Poster

The End