Effects of natural and artificial barriers on the genetic diversity of game species: a review.

Bendegúz Mihalik, Szilvia Kusza, Viktor Stéger, George Wanjala, Zsolt Németh


Barriers are various natural or artificial borders that fragment the landscape. They reduce the habitat, block pathways and separate the populations into smaller segments. A natural barrier may be a sierra, a valley, a river, a sea, the distance between optimal habitats etc. Human-related barriers are the roads, fences and cities.

The following hypothesis was tested: the barrier-effect’s strength depends on the barrier itself as well as on the size, migratory behavior and other properties of the affected species. This review was written with the focus on the species size, the barrier type and the effect’s strength in the case of multiple species and barriers.

The results are mostly in agreement with this hypothesis, but it is revealed that the evaluation is not fully standardized yet. Wright’s Fst value is an exact number, but researchers have handled it differently. In some cases they were more permissive and ascribed less impact (mostly in the case of low Fst values). On the other hand, there are authors who valorized the low Fst values because of the possible cascade effect caused by genetic division and changing behaviour.

This review describes the possible effects of barriers, but every species and habitat is unique, therefore the method described should not be regarded as 100% accurate. With this comparing technique the effects may be predicted more precisely prior to carrying out the impact studies, thus the additional costs and the impact on the actual species will be easier to estimate.


natural barrier, artificial barrier, game, genetic diversity, review

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Allcock, A.L., Brierley, A.S., Thorpe, J.P., Rodhouse, P.G. (1997). Restricted gene flow and evolutionary divergence between geographically separated populations of the Antarctic octopus Pareledone turqueti. Marine Biology 129: 97-102.

Andrews, A. (1990). Fragmentation of Habitat by Roads and Utility Corridors: A Review. Australian Zoologist 26(3&4), 130-141.

Aresco, M. J. (2005). The effect of sex-specific terrestrial movements and roads on the sex ratio of freshwater turtles. Biological Conservation, 37–44.

Ballók Zs. (2011). A vonalas létesítmények szerepe a gímszarvas területhasználatában. Doktori értekezés, Sopron. 83 pp.

Bernardi, G. (2000). Barriers To Gene Flow In Embiotoca Jacksoni, A Marine Fish Lacking A Pelagic Larval Stage. Evolution, 226–237.

Bhattacharya, M., Primack, R.B., Gerwein, J. (2003). Are roads and railroads barriers to bumblebee movement in a temperate suburban conservation area? Biological Conservation 109: 37-45.

Bihari, Z., Antal, Zs., Gyüre P. (2011). Természetvédelmi ökológia. Debreceni Egyetem, Debrecen. 60 pp.

Carr, L.W. & Fahrig, L. (2001). Effect of road traffic on two amphibian species of differing vagility. Conservation Biology 15(4): 1071-1078.

Castella, V., Ruedi, M., Excoffier, L., Ibáñez, C., Arlettaz, R., & Hausser, J. (2000). Is the Gibraltar Strait a barrier to gene flow for the bat Myotis myotis(Chiroptera: Vespertilionidae)? Molecular Ecology 9, 1761–1772.

Caswell, H. (2001). Matrix Population Models: Construction, Analysis and Interpretation, second ed. Sinauer Associates, Sunderland, MA.

Caughley, G., Grigg, G.C., Caughley, J., Hill, G.J.E. (1980). Does dingo predation control the densities of kangaroos and emus? Australian Wildlife Research 7, 1-12.

Clark, R. W., Brown, W. S., Stechert, R., & Zamudio, K. R. (2010). Roads, Interrupted Dispersal, and Genetic Diversity in Timber Rattlesnakes. Conservation Biology, 1059–1069.

Clevenger, A.P., Chruszcz, B., Gunson, K.E. (2003). Spatial patterns and factors influencing small vertebrate fauna road-kill aggregations. Biological Conservation 109, 15-26.

Corlatti, L., Hacklander, ,. K., & Frey-Roos, F. (2009). Ability of Wildlife Overpasses to Provide Connectivity and Prevent Genetic Isolation. Conservation Biology, 548–556.

Coulon, A., Guillot, G., Cosson, J-F., Angibault, J.M.A., Aulagnier, S., Cargnelutti, B., Galan, M., Hewison, A.J.M. (2006). Genetic structure is influenced by landscape features: empirical evidence from a roe deer population. Molecular Biology 15, 1669-1679.

Crispo, E., Bentzen, P., Reznick, D. N., Kinnison, M. T., & Hendry, A. P. (2006). The relative influence of natural selection and geography on gene flow in guppies. Molecular Ecology, 49-62.

Cushman, S. A., McKelvey, K. S., Hayden, J., & Schwartz, M. (2006). Gene Flow in Complex Landscapes: Testing Multiple Hypotheses with Causal Modeling. The American Naturalist, 486-499.

D'Amico, M., Périquet, S., Román, J. & Revilla, E. (2016). Road avoidance responses determine the impact of heterogeneous road networks at a regional scale. Journal of Applied Ecology 53, 181–190.

Dodd, Jr. C.K., Barichivich, W.J., Smith, L.L. (2004). Effectiveness of a barrier wall and culverts in reducing wildlife mortality on a heavily traveled highway in Florida. Biological Conservation 118, 619-631.

Epps, C. W., Palsbøll, J. P., Wehausen, J. D., Roderick, G. K., Ramey II, R. R., & McCullough, D. R. (2005). Highways block gene flow and cause a rapid decline in genetic diversity of desert bighorn sheep. Ecology Letters, 1029–1038.

Ernest, H. B., Boyce, W. M., Bleich, V. C., May, B., Stiver, S. J., & Torres, S. G. ( 2003). Genetic structure of mountain lion (Puma concolor) populations in California. Conservation Genetics , 353–366.

Feischmidt M. & Szerbhorváth Gy. (2017). Mezsgyevilágok helyett kerítések: felügyelet és biopolitika. Néprajzi Látóhatár 1-4. 206-233

Ferreira E, Souto L, Soares AMVM, Fonseca C (2006) Genetic structure of the wild boar (Sus scrofa L.) population in Portugal. Wildl Biol Pract 2:17–25

Ferreira E, Souto L, Soares AMVM, Fonseca C (2009) Genetic structure of the wild boar population in Portugal: evidence of recent bottleneck. Mamm Biol 74:274–285

Forman, R. T., & Alexander, L. (1998). Roads And Their Major Ecological Effects. Annu. Rev. Ecol. Syst., 207–231.

Forman, R.T.T. & Deblinger, R.D. (1998). The ecological road-effect zone for transportation planning and Massachusetts highway example. ICOWET 1998, February 9-12. 78-96.

Forman, R.T.T. & Deblinger, R.D. (2000). The ecological road-effect zone of a Massachusetts (U.S.A.) suburban highway. Conservation Biology 14(1): 36-46.

Frantz, A. C., Bertouille, S., Eloy, M. C., Licoppe, A., Chaumont, F., & Flamand, M. C. (2012). Comparative landscape genetic analyses show a Belgian motorway to be a gene flow barrier for red deer (Cervus elaphus), but not wild boars (Sus scrofa). Molecular Ecology, 1-13.

Funk , W. C., Blouin , M. S., Corn, P. S., Maxell , A. B., Pilliod , S. D., Amish , S., & Allendorf , W. F. (2005). Population structure of Columbia spotted frogs (Rana luteiventris) is strongly affected by the landscape. Mol Ecol., 483-96.

Garamszegi L.Zs., Hargitai R., Hegyi G., Michl, G., Rosivall, B., Szigeti, B., Szöllősi, E., Tóth L., Török J. (2009). Egy összetett szignalizációs mechanizmus: a madárének lokális, regionális és evolúciós mintázatai. OTKA Project Report. 9 pp.

Genov P., Nikolov H., Massei G. and Gerasimov S. 1991. Craniometrical analyses of Bulgarian wild boar. Journal of Zoology, London 225: 309–325.

Gerlach, G., & Musolf, K. (2000). Fragmentation of Landscape as a Cause for Genetic Subdivision in Bank Voles. Conservation Biology, 1066–1074.

González-Candelas, F. &Francino, M.P. (2012). Barriers to horizontal gene transfer: fuzzy and evolvable boundaries. IN: Francino, M.P. (editor): Horizontal gene transfer in microorganisms. Carister Academic Press, Norfolk, UK. 47-73.

Hartl G. B., Markov G., Rubin A., Findo S., Lang G. and Willing R. 1993. Allozyme diversity within and among populations of three ungulate species (Cervus elaphus, Capreolus capreolus, Sus scrofa) of South-eastern and Central Europe. Zeitschrift für Säugetierkunde 58: 352–361.

Hels, T., & Buchwald, E. (2001). The effect of road kills on amphibian populations . Biological Conservation, 331–340.

Hermansen, J.S., Saether, S.A., Elgvin, T.O., Borge, T., Hjelle, E., Saetre, G-P. (2011). Hybrid speciation in sparrows I: phenotypic intermediacy, genetic admixture and barriers to gene flow. Molecular Ecology 20: 3812-3822.

Hershkovitz, P. (1977). Living New World monkeys (Platyrrhini) with an introduction to primates. University of Chicago Press, Chicago.

Hitchings, S.P. & Beebee, T.J.C. (1996). Genetic substructuring as a result of barriers to gene flow in urban Rana temporaria (common frog) populations: implications for biodiversity conservation. Heredity 79: 117-127

Irwin, D.E. (2002). Phylogeographic breaks without georgraphic barriers to gene flow. Evolution 56(12): 2383-2394.

Ito, T. Y., Okada, A., Buuveibaatar, B., Lhagvasuren, B., Takatsuki, S., & Tsunekawa, A. (2008). One-sided barrier effect of an international railroad on Mongolian gazelles. Journal of Wildlife Management, 72, 940–943.

Ito, T. Y., Lhagvasuren, B., Tsunekawa, A., Shinoda, M., Takatsuki, S., Buuveibaatar, B., et al. (2013). Fragmentation of the habitat of wild ungulates by anthropogenic barriers in Mongolia. PLoS ONE, 8, e56995.

Janás L. (2017). Az országos közutak 2016. évre vonatkozó keresztmetszeti forgalma. One Planet Mérnökiroda Kft. Budapest. 407 pp.

Kociolek, A. & Clevenger, A. (2007). Highway median impacts on wildlife movement and mortality. IN: Proceedings of the 2007 International Conference on Ecology and Transportation, edited by Irwin, C.L., Nelson, D., McDermott, K.P. 609-612

Kornilev, Y. V., Price, S. J., & Dorcas, M. E. (2006). Between a rock and a hard place: Responses of eastern box turtles (Terrapene carolina) when trapped between railroad tracks. Herpetological Review 37, 145–148

Lasky, J.R., Jetz, W., Keitt, T.H. (2011). Conservation biogeography of the US-Mexico border: a transcontinental risk assessment of barriers to animal dispersal. Diversity and Distributions 17, 673-687

Lesbarreres, D., Primmer, R.C., Lodé, T., Merila, J. (2006): The effects of 20 years of highway presence on the genetic structure of Rana dalmatina populations. Ecoscience 13(4): 531-538

Lugon-Moulin, N. & Hausser, J. (2002). Phylogeographical structure, postglacial recolonization and barriers to gene flow in the distinctive Valais chromosome race of the common shrew (Sorex araneus). Molecular Ecology 11: 875-794

Macnab, J. (1983). Wildlife Management as a scientific experimentation. Wildlife Society Bulletin 11(4), 397-401

Markov G. 1954. On the systematic of the wild boar in Bulgaria. Bulletin de l’ Institut Zoologique de l’Academie Bulgare des Sciences 3: 221–223

McRae, B.H., Beier, P., Dewald, L.E., Huynh, L.Y., Keim, P. (2005). Habitat barriers limit gene flow and illuminate historical events in a winde-ranging carnivore, the American puma. Molecular Ecology 14, 1965-1977

Moore, G. T., & Mangel, M. (1996). Traffic related mortality and the effects on local populations of barn owls Tyto alba. In: Evink, G.L., Garrett, P., Zeigler, D., Berry, J. (Eds.), Trends in Addressing Transportation Related Wildlife Mortality. Proceedings of the Transportation Related Wildlife Mortality Seminar. Florida Department of Transportation Report FL-ER-58-96

Murphy, S.M. & Curatolo, J.A. (1987). Activity budgets and movements of caribou encountering pipelines, roads and traffic in northern Alaska. Canadian Journal of Zoology 65: 2483-2490

Németh A., Krnács Gy., Tamás Á., Vajda Z. (2015). A délvidéki földikutya (Nannospalax montanosyrmiensis) magyarországi állományainak alapállapot felmérése. Report for the Raptorspreslife LIFE+ tender. 15 pp.

Nikolov I. S., Gum B., Markov G. and Kuehn R. 2009. Population genetic structure of wild boar Sus scrofa in Bulgaria as revealed by microsatellite analysis. Acta Theriologica 54: 193–205

Olson, K. A. (2013). Saiga crossing options: Guidelines and recommendations to mitigate barrier effects of border fencing and railroad corridors on saiga antelope in Kazakhstan. Smithsonian Conservation Biology Institute.

Olson, K. A., & van der Ree, R. (2015). Railways, roads and fences across Kazakhistan and Mongolia threaten the survival of wide-ranging wildlife. In R. van der Ree, D. J. Smith, & C. Grilo (Eds.), Handbook of road ecology. 472–478

Ostfeld, R.S. (1994). The fence effect reconsidered. Oikos 70(3): 340-348

Patton, J. L., Malcolm, J. R., & Da Silva, M. N. (1994). Gene Genealogy And Differentiation Among Arboreal Spiny Rats (Rodentia: Echimyidae) Of The Amazon Basin: A Test Of The Riverine Barrier Hypothesis. Evolution. , 1314-1323

Pérez-Espona, S., Pérez-Barbería, F.J., McLeod, J.E., Jiggins, C.D., Gordon, I.J., Pemberton, J.M. (2008). Landscape features affect gene flow of Scottish Highland red deer (Cervus elaphus). Molecular Ecology 17: 981-996

Randi, E., Massei, G. and Genov, P. 1992. Allozyme variability in Bulgarian wild boar populations. Acta Theriologica 37: 271–278

Reesa, C. Y., & Mill, L. S. (2003). Highway as a potential barrier to movement and genetic exchange in small mammals. University of Montana: Wildlife Biology program.

Riley, S. P., Pollinger, J. P., Sauvajot, R. M., York, E. C., Cassity, B., Fuller‡, T. K., & Wayne, R. K. (2006). A southern California freeway is a physical and social barrier to gene flow in carnivores. Molecular Ecology, 1733–1741

Rosell, C., Navas, F., Pou, M.F., Carol, J. (2008). Wild boar vehicle collisions. Spatial and temporal patterns and measures for the mitigation of the conflict. Proceedings of the 7th International Symposiumon Wild Boar (Sus scrofa) and Sub-order Suiformes: 91-93

Rosell, C., Fernández-Bou, M., Camps, F., Boronat, C., Navás, F., Martínez, M., Sorolla, A. (2013). Animal-vehicle collisions: a new cooperative strategy is needed to reduce the conflict. Proceedings of the 2013 International Conference on Ecology and Transportation, 2-14

Rosen, P. C., & Lowe, C.H, H. C. (1994). Highway mortality of snakes in the Sonoran desert of southern Arizona. Sonoran desert of southern Arizona, 143–148

Rueness, E. K., Stenseth, N. C., Donoghue, M. O., Boutin, S., Ellegren, H., & Jakobsen, K. S. (2003). Ecological and genetic spatial structuring in the Canadian lynx. NATURE, 69-72

Sanchez-Montes, G., Wang, J., Arino, A. H., & Martınez-Solano, I. (2017). Mountains as barriers to gene flow in amphibians: Quantifying the differential effect of a major mountain ridge on the genetic structure of four sympatric species with different life history traits. Journal of Biogeography. 2017, 1-14

Sawaya, M., Kalinowski, S. T., & Clevenger, A. P. (2014). Genetic connectivity for two bear species at wildlife crossing structures in Banff National Park. Proc Biol Sci., 1-10

Scandura M., Iacolina L., Crestanello B., Peccholi E., Benedetto M. F., Di Russo V., Davoli R., Apollonio M. and Bertorelle G. 2008. Ancient vs. recent processes as factors shaping the genetic variation of the European wild boar: are the effects of the last glaciation still detectable? Molecular Ecology 17: 1745–1762

Seiler, A. (2001). Ecological Effects of Roads; A review. Grimsö Wildlife Research Station, Dept. of Conservation Biology, University of Agricultural Sciences, 1-39

Shaw, P. W., Carvalho, G. R., Magurran, A. E., & Seghersf, B. H. (1994). Factors affecting the distribution of genetic variability in the guppy, Poecilia reticulata. Jounal of FIsh Bology, 875-888

Shirk, A.J., Wallin, D.O., Cushman, S.A., Rice, C.G., Warheit, K.I. (2010): Inferring landscape effects on gene flow: a new model selection framework. Molecular Ecology: 3603-3619

Sprem N, Safner T, Treer T, Florijancic T, Jurić J, Cubric-Curic V et al. (2016). Are the dinaric mountains a boundary between continental and mediterranean wild boar populations in Croatia? Eur J Wildl Res 62: 167–177

Steele, C. A., Baumsteiger, J., & Storfer, A. (2009). Influence of life-history variation on the genetic structure of two sympatric salamander taxa. Molecular Ecology, 1629–1639

Vallinoto, M., Araripe, J., do Rego, P. S., Tagliaro, C. H., Sampaio, I., & Schneider, H. (2006). Tocantins river as an effective barrier to gene flow in Saguinus niger populations. Genetics and Molecular Biology, 215-219.

Vanak, A.T., Thaker, M., Slotow, R. (2010). Do fences create an edge-effect on the movement patterns of a highly mobile mega-herbivore? Biological Conservation 143, 2631-2637

Vernesi C., Crestanello B., Pecchioli E., Tartari D., Caramelli D., Hauffe H. and Bertorelle G. 2003. The genetic impact of demographic decline and reintroduction in the wild boar (Sus scrofa): A microsatellite analysis. Molecular Ecology 12: 585–595

Wanjala, G., Mihalik B., Stéger V., Kusza Sz. (2017): Lake Balaton as a geographical barrier for gene flow between wild boar (Sus scrofa) populations in Hungary. Acta Agronomica Óváriensis 58(2): 36-55

Willey, R. B., & Willey, R. L. (1967): Barriers To Gene Flow In Natural Populations Of Grasshoppers. Psyche.

Wright, S. (1978): Evolution and the genetics of populations. vol. 4 variability within and among natural populations. University of Chicago Press, Chicago. 590 pp.

Zhan, A., Li, C., & Fu, J. (2009): Big mountains but small barriers: Population genetic structure of the Chinese wood frog (Rana chensinensis) in the Tsinling and Daba Mountain region of northern China. BMC Genetics, 10,17

DOI: http://dx.doi.org/10.15679/bjwr.v5i1.61


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