E-mail: rlj@astate.edu

ACADEMIC TRAINING

B.S. in Marine Biology at Cal. St. Univ., Long Beach - 1977

M.A. in Biology at University of Northern Colorado - 1981

D.A. in Biology at University of Northern Colorado - 1984

RESEARCH AREAS AND INTERESTS

o Environmental Genetics

o Molecular Systematics

o Fish Health Assessment

o Stream Systems Analysis

RESEARCH

Arkansas State University's location adjacent to three physiographic regions provides for a rich variety of waterways, and, therefore, a high diversity of freshwater fauna. Man's activities have impacted the environment in numerous ways, resulting in range reduction in some species and expansion in range for other species. My research focus has been on the population genetics of groups which have been environmentally impacted by stocking/harvesting programs and other anthropogenic effects. Much of my research has been investigating the genetics of the blackbasses (Micropterus) and catfishes (Ictalurus) by way of allozyme and mitochondrial DNA analysis. Additionally, bivalves are species rich and have been impacted more than any other freshwater group; water quality changes and shell harvesting can dramatically effect genetic diversity and structure. I have also been involved in several projects studying stream dynamics of sportfishes.

 

CURRENT GRADUATE STUDENTS

Joy Trauth, Ph.D. A metapopulation study of gene flow and genetic structuring of the Illinois Chorus Frog (Pseudacris streckeri illinoensis) in Arkansas

Tiffany Sanders, M.A.  Phylogenetic analysis of certain unionid species of Lampsilis.

Travis Harmon, M.S.  A survey of the macroinvertebrates and brown trout feeding habits within the Little Red River, AR.

 

Michael Weston, M.S.  Patterns of movement at multiple spatial scales and population estimates of Etheostoma moorei Raney and Suttkus (Pisces: Percidae).

 

SELECTED PUBLICATIONS

S.D. Henry, S.W. Barkley and R.L. Johnson. 2005. Exploitation of Nile Tilapia in a closed system, public fishing reservoir in northern Arkansas. North American Journal of Fisheries Management 25:853-860.

J. B. Trauth, S. E. Trauth, and R. L. Johnson. 2005. Precision land leveling silences the Illinois chorus frog (Pseudacris streckeri illinoensis) of northeastern Arkansas. Wildlife Society Bulletin (in press).

A. Sako, C.M. O’Reilly, R. Hannigan, N. Bickford and R.L. Johnson. 2005. Stock identification of two clupeid species, Stolothrissa tanganicae and Limnotrhrissa miodon in Lake Tanganyika using otolith microchemistry. J. Association of Exploration Geochemists 5:91-97.

R. L. Johnson and G. L. Harp. 2004. Spatio-temporal changes of benthic macroinvertebrates in a cold Arkansas tailwater. Hydrobiologia 537:15-24.

R.L. Johnson and T. Fulton. 2004. Incidence of Florida largemouth alleles in two northern Arkansas populations of largemouth bass, Micropterus salmoides Lacepede. American Midland Naturalist 152:225-229.

R.L. Johnson and K. A. Williams. 2003. Genetic relationships of some common Arkansas freshwater sunfishes (Centrarchidae: Lepomis) inferred from restriction endonuclease analysis of mitochondrial DNA. Arkansas Academy of Sciences 57:95-99.

R.L. Johnson and C. F. Cavenaugh. 2003. Genetic similarity of shadow and Ozark basses (Ambloplites) as determined by mitochondrial DNA analysis. Arkansas Academy of Sciences 57:204-208.

Johnson, R.L., J. Magee and T. A. Hodge. 2002. Phylogenetics of freshwater black basses (Centrarchidae: Micropterus) inferred from restriction endonuclease analysis of mitochondrial DNA. Biochemical Genetics 39:396-406.

Mitchell, R.M., R.L. Johnson and G.L. Harp. 2002. Population structure of an endemic species of yellowcheek darter, Etheostoma moorei (Raney and Suttkus), of the upper Little Red River, Arkansas. American Midland Naturalist 148:129-137.

Johnson, R.L. and R.S. Staley. 2001. Identification of Florida largemouth bass alleles in Arkansas public and private aquaculture ponds. Arkansas Academy of Sciences 55:82-85.

Johnson, R.L., D. Ward and R. S. Grippo. 2000. Physicochemical and macroinvertebrate assemblages of riffles upstream and downstream of a streambank impacted by unrestricted cattle access. Arkansas Academy of Sciences 54:68-76.

Johnson, R.L. and W.T. Fulton. 1999. Persistence of Florida largemouth bass alleles in a northern Arkansas population of largemouth bass. Ecology of Freshwater Fish 8:35-42.

Johnson, R.L., F.Q. Liang, C.D. Milam and J.L. Farris. 1999. Genetic diversity and cellulolytic activity among several species of Unionid bivalves in Arkansas. Journal of Shellfish Research 17:(5):1375-1382.

Johnson, R.L., F.Q. Liang and J.L. Farris. 1999. Genetic relationships of several Amblemini species (Bivalvia: Unionidae) in Arkansas. Journal of Shellfish Research 17: 1237-1242.

Johnson, R.L., F.Q. Liang, and J.L. Farris. 1998. Genetic diversity among four Amblemini species (Bivalvia: Unionidae) in the Cache and White rivers, Arkansas. Southwestern Naturalist 43(3):321-332.

Johnson, R.L. and R.M. Davis. 1997. Age, growth and condition of largemouth bass, Micropterus salmoides, of Lake Ashbaugh, Arkansas. Arkansas Academy of Sciences 51:95-102.

Johnson, R.L. and J. Pignatare. 1994. Restriction fragment length polymorphisms in the largemouth bass, Micropterus salmoides salmoides, in a small Massachusetts kettlehole. American Midland Naturalist 133:364-367.
 

SELECTED GRANTS

Arkansas Game and Fish Commission. Genetic and Morphologic Diversity and Relatedness in and Among Populations of Illinois Chorus Frogs (Pseudacris streckeri illinoensis) and Strecker’s Chorus Frogs (P. s. streckeri) in Arkansas. Co-author. 9/1/04-present. $65,994.

US Fish and Wildlife Service. Migration of yellowcheek darters (Etheostoma moorei) in the Little Red River watershed. Completed 2004. $17,000.

US Fish and Wildlife Service. Gene flow and genetic structuring of yellowcheek darters (Etheostoma moorei) in the Little Red River watershed. Completed 2005. $5,000.

Arkansas Game and Fish Commission. A bioenergetic and food web analysis of factors limiting brown trout growth in the Little Red River, AR tailwaters: Potential for management options? Co-author. Completed 2003. $2,500.

Arkansas Game and Fish Commission. Species limits and phylogeography of Lampsilinae (Bivalvia: Unionidae) in Arkansas with emphasis on species of Lampsilis. Co-author. Completed 2004. $58,935.

ASU Faculty Research Grant. Relationship of gene flow to geographic distance in two species of polychaetes with different dispersal capabilities.  $8,200. Completed 2001.

Arkansas Game and Fish Commission. A survey of the macroinvertebrates and brown trout feeding habits within the Little Red River. $10,764. Completed 2001.

Arkansas Soil and Water Conservation Commission. Demonstration of streambank restoration on the Southfork of the Spring River, Arkansas. Co-author. $60,000. Completed 2002.

Arkansas Science and Technology Authority. Genetic distance of and evolution of  the Micropterid basses as determined by mitochondrial DNA analysis. $35,406. Completed 1996.