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Grazing pressure and the interaction dynamics of the endemic Cyprus Warbler Sylvia melanothorax and its recently colonising congener the Sardinian Warbler S. melanocephala

Published online by Cambridge University Press:  27 April 2020

MARTIN A. HELLICAR
Affiliation:
Dept. of Biological Sciences, University of Cyprus, PO Box 20537, Nicosia 1678, Cyprus. BirdLife Cyprus, PO Box 12026, Nicosia 2340, Cyprus.
ALEXANDER N.G. KIRSCHEL*
Affiliation:
Dept. of Biological Sciences, University of Cyprus, PO Box 20537, Nicosia 1678, Cyprus.
*
*Author for correspondence; email: [email protected]

Summary

The recent classification of the endemic Cyprus Warbler to a Species of European Conservation Concern by BirdLife International has renewed interest in its interaction with the Sardinian Warbler, a widespread Sylvia that was first confirmed as breeding in Cyprus in the 1990s and has since expanded in numbers and range. In areas where the Sardinian Warbler has become established, there has been a reduction in the abundance of the Cyprus Warbler, leading some researchers to suggest the recently arrived species is outcompeting its endemic congener. However, clear evidence of competition between the two species has not been found, and more recent research has suggested the closely related warbler species show preferences for subtly different scrub habitats, which might be influenced by the extent of grazing. We carried out line transect surveys during the breeding season at 48 scrub and open woodland sites across Cyprus in 2012, 2014 and 2016, recording Cyprus Warblers and Sardinian Warblers in order to estimate their densities. In addition, we recorded vegetation characteristics and estimated grazing pressure at these 48 sites. Our analysis showed that the Sardinian Warbler continues to increase in abundance over time and its higher abundances were associated with lower Cyprus Warbler abundances. Sardinian Warbler however was negatively associated with all but very low grazing pressure, whereas the Cyprus Warbler was more tolerant of grazing. Our findings suggest continued grazing of scrub sites is important for the maintenance of suitable habitat for the endemic warbler, which will help improve its conservation status.

Type
Research Article
Copyright
© The Author(s), 2020. Published by Cambridge University Press on behalf of BirdLife International

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References

Agra, H. and Ne’eman, G. (2009) Woody species as landscape modulators: their effect on the herbaceous plants in a Mediterranean maquis. Plant Ecol. 205: 165-177.CrossRefGoogle Scholar
Allen, H. D. (2001) Mediterranean ecogeography. Harlow, UK: Pearson Education limited.Google Scholar
Begon, M., Townsend, C. R. and Harper, J. L. (2006) Ecology, from individuals to ecosystems. Oxford, UK: Blackwell Publishing.Google Scholar
Bibby, C. J., Burgess, N. D., Hill, D. A. and Mustoe, S. H. (2000) Bird census techniques. London, UK: Academic Press.Google Scholar
BirdLife International (2004) Birds in Europe: population estimates, trends and conservation status. Cambridge, UK: BirdLife International.Google Scholar
BirdLife International (2017) European birds of conservation concern: populations, trends and national responsibilities. Cambridge, UK: BirdLife International Google Scholar
Blondel, J. and Aronson, J. (1999) Biology and wildlife of the Mediterranean region. Oxford, UK: Oxford University Press.Google Scholar
Brown, W. L. Jr. and Wilson, E. O. (1956) Character displacement. Syst. Zool. 5: 49-64.CrossRefGoogle Scholar
Carroll I, T., Cardinale, B. J. and Nisbet, R. M. (2011) Niche and fitness differences relate the maintenance of diversity to ecosystem function. Ecology 92: 1157-1165 CrossRefGoogle ScholarPubMed
Christodoulou, D. (1959) The evolution of the rural land use pattern in Cyprus – The world land use survey Monograph 2. Bude, UK: Geographical Publications.Google Scholar
Cody, M. L. (1969) Convergent characteristics in sympatric species: a possible relation to interspecific competition and aggression. Condor 71: 222-239.CrossRefGoogle Scholar
Cottam, G. and Curtis, J. T. (1956) The use of distance measures in phytosociological sampling. Ecology 37: 451-460.CrossRefGoogle Scholar
Cozens, V. and Stagg, A. (1998) The status of Sardinian Warbler and Cyprus Warbler in the northwest of Cyprus. Royal Air Force Ornithol. Soc. J. 2: 25-29.Google Scholar
Cozens, V., Stewart, P. and Pomeroy, D. (2000) Why has Sardinian Warbler Sylvia melanocephala invaded Cyprus? Sandgrouse 22: 6-9.Google Scholar
Economides, S. (1997) Cyprus country chapter. Pp. 49-52 in Thomson, R., von Kaufman, H., Pun, L., Treacher, T. and van Hauten, H, eds. Global agenda for livestock research. Proceedings of a Consultation on Setting Livestock Research Priorities in West Africa and North Africa (WANA) Region . Aleppo, Syria: International Centre for Agricultural Research in the Dry Areas.Google Scholar
Eliades, N., Andreou, M., Kounnamas, C., Avraam, E., Parisi, Z., Maliotis, S. and Kyriazopoulos, A. (2016) Assessment of grazing capacity and preparation of grazing management plan for the Akamas Peninsula. Nicosia, Cyprus: A. M. Filagrotiki Consultants Ltd.Google Scholar
FAO Global Forests Resource Assessment (2010) Country Report Cyprus. Rome: FAO report for the Global Forest Resources Assessment 2010.Google Scholar
Flint, P. and McArthur, A. (2014) Is the Sardinian Warbler Sylvia melanocephala displacing the endemic Cyprus Warbler S. melanothorax on Cyprus? Sandgrouse 36: 63-109.Google Scholar
Flint, P. R. and Stewart, P. F. (1992) The birds of Cyprus. 2nd Edition. Tring, UK: British Ornithologists’ Union.Google Scholar
Freschi, P., Musto, M., Paolino, R., Cosentino, C. (2015) Grazing and biodiversity conservation: highlights on a Natura 2000 Network site. Pp. 271-288 in Vastolam, A. ed. The sustainability of agro-food and natural resource systems in the Mediterranean Basin. Heidelebrg: Springer Open Google Scholar
Frost, R. (1995) The Sardinian Warbler breeding in Cyprus. Cyprus Ornithological Society (1957) 41st Annual Report 1994: 7981.Google Scholar
Giourga, H., Margaris, N. and Vokou, D. (1998) Effects of grazing pressure on succession process and productivity of old fields on Mediterranean Islands. Environ. Manage. 22: 589-596.Google ScholarPubMed
Grether, G. F., Anderson, C. N., Drury, J. P., Kirschel, A. N. G., Losin, N. and Okamoto, K. (2013) The evolutionary consequences of interspecific aggression. Ann. N.Y. Acad. Sci. 1289: 48-68.CrossRefGoogle ScholarPubMed
Gross, N., Suding, K.N., Lavorel, S. and Roumet, C. (2007) Complementarity as a mechanism of coexistence between functional groups of grasses. J. Ecol. 95: 1296-1305.CrossRefGoogle Scholar
Grove, A. T and Rackham, O. (2001) The nature of Mediterranean Europe, An ecological history. London: Yale University Press.Google Scholar
Harris, S. E. (2007) Colonial forestry and environmental history: British policies in Cyprus, 1878–1960. PhD Thesis. The University of Texas at Austin.Google Scholar
Hellicar, M. A. and Ieronymidou, C. (2017) Ten years of the BirdLife Cyprus Common Bird Monitoring Scheme, 2006–2015. Bird Census News 30/1: European Monitoring News 17-23.Google Scholar
Hellicar, M. A. and Kirschel, A. N. G. (2019) How grazing and other disturbance factors influence biodiversity in Cyprus, with a focus on breeding bird communities. bioRxiv. http://dx.doi.org/10.1101/860296 CrossRefGoogle Scholar
Hellicar, M. A., Anastasi, V., Beton, D. and Snape, R. (2014) Important Bird Areas of Cyprus. Nicosia, Cyprus: BirdLife Cyprus.Google Scholar
Hellicar, M. A., Honold, J. and Kirschel, A. N. G. (2019) Comparison of land cover and farming intensity-based models for mapping High Nature Value farmland in Cyprus. Bird Study 66: 317-328.CrossRefGoogle Scholar
Ieronymidou, C. (2012) Avian land-use associations in the Eastern Mediterranean. PhD Thesis. University of East Anglia.Google Scholar
Ieronymidou, C., Collar, N. J. and Dolman, P. M. (2012) Endemic Cyprus Warbler Sylvia melanothorax and colonizing Sardinian Warbler Sylvia melanocephala show different habitat associations. Ibis 154: 248-259 CrossRefGoogle Scholar
Jetz, W., Wilcove, D. S. and Dobson, A. P. (2007) Projected impacts of climate and land-use change on the global diversity of birds. PLoS Biol. 5: e157.CrossRefGoogle Scholar
Jones, V. R. (2006) Comparative ecology of the endemic Cyprus Warbler and the congeneric Sardinian Warbler: implications of recent coexistence. PhD thesis. University of Cambridge.Google Scholar
Kirschel, A. N. G., Blumstein, D. T. and Smith, T. B. (2009) Character displacement of song and morphology in African tinkerbirds. Proc. Natl. Acad. Sci. USA 106: 8256-8261.CrossRefGoogle Scholar
Kirschel, A. N. G., Seddon, N., and Tobias, J. A. (2019) Range-wide spatial mapping reveals convergent character displacement of bird song. Proc. R. Soc. B. Lond. 286: 20190443Google ScholarPubMed
Krebs, C. J. (1999) Ecological Methodology. 2nd Edition. Menlo Park: Benjamin Cummings.Google Scholar
Malcolm, J. R., Liu, C., Neilson, R. P., Hansen, L. and Hannah, L. (2006) Global warming and extinctions of endemic species from biodiversity hotspots. Conserv. Biol. 20: 538-548.CrossRefGoogle ScholarPubMed
MARDE (2017) Review of goat and sheep rearing 2016. Report by the Cyprus Ministry of Agriculture, Rural Development and Environment (MARDE), Department of Agriculture. Nicosia.Google Scholar
Mitchell, K. (2007) Quantitative analysis by the point-centered quarter method. Downloaded from http://people.hws.edu/mitchell/PCQM.pdf Google Scholar
Mooney, H. A. and Cleland, E. E. (2001) The evolutionary impact of invasive species. Proc. Natl. Acad. Sci. U.SA. 98: 5446-5451.CrossRefGoogle ScholarPubMed
Nwankwo, E. C., Mortega, K. G., Karageorgos, A., Ogolowa, B. O., Papagregoriou, G., Grether, G. F., Monadjem, A., and Kirschel, A. N. G. (2019) Rampant introgressive hybridization in Pogoniulus tinkerbirds (Piciformes: Lybiidae) despite millions of years of divergence. Biol. J. Linn. Soc. 127: 125-142 CrossRefGoogle Scholar
Papanastasis, V. P. and Kazaklis, A., (1998) Land use changes and conflicts in the Mediterranean – type ecosystems of western Crete. Pp. 141-154 in Rundel, P. W., Montenegro, G. and Jaksic, F M., eds. Landscape degradation and biodiversity in Mediterranean–type ecosystems. Berlin: Springer Verlag. Ecological Studies, Vol. 136.CrossRefGoogle Scholar
Papanastasis, V. P., Kyriakakis, S. and Kazakis, G. (2002) Plant diversity in relation to overgrazing and burning in mountain Mediterranean ecosystems . J. Mediterranean Ecol. 3: 353-363.Google Scholar
Pomeroy, D. and Walsh, F. (2000) Is Sardinian Warbler Sylvia melanocephala displacing Cyprus Warbler S. melanothorax in Cyprus? Sandgrouse 22: 44-49.Google Scholar
Pomeroy, D. and Walsh, F. (2002) A European endemic warbler under threat? Population changes in Sylvia warblers on the island of Cyprus. Oryx 36: 342-348.CrossRefGoogle Scholar
Pomeroy, D., Walsh, F., Flint, P., Hellicar, M. and Shaw, P. A. (2016) A sustained decline in Cyprus Warbler Sylvia melanothorax numbers in western Cyprus, coinciding with the colonisation of its breeding range by the Sardinian Warbler S. melanocephala . Bird Conserv. Internatn. 26: 436-450.CrossRefGoogle Scholar
Team, R Core (2019) R: A language for statistical computing. Vienna: Austria: R Foundation for Statistical Computing.Google Scholar
Sales-Baptista, E., D’Abreu, M. C. and Ferraz-De-Oliveira, M. I. (2016) Overgrazing in the Montado? The need for monitoring grazing pressure at the paddock scale. Agroforest. Syst. 90: 57. https://doi.org/10.1007/s10457-014-9785-3CrossRefGoogle Scholar
Schielzeth, H. (2010) Simple means to improve the interpretability of regression coefficients. Methods Ecol. Evol. 1: 103-113.CrossRefGoogle Scholar
Shachak, M., Boeken, B., Gruner, E., Kadmon, R., Lubin, Y., Meron, E., Ne’eman, G., Perevolotsky, A. and Shkedy, Y. (2008) Woody species as landscape modulators and biodiversity patterns. Bioscience 58: 209-221.CrossRefGoogle Scholar
Shirihai, H., Gargallo, G. and Helbig, A. J. (2001) Sylvia warblers. London, UK: Christopher Helm.Google Scholar
Stylianou, J. (2016) Cyprus bird report 2014. Nicosia, Cyprus: BirdLife Cyprus.Google Scholar
Stylianou, J. (2017) Cyprus bird report 2015. Cyprus. Nicosia: BirdLife Cyprus.Google Scholar
Stylianou, J. (2018) Cyprus bird report 2016. Nicosia, Cyprus: BirdLife Cyprus.Google Scholar
Sutherland, W. J., ed. (2000) Ecological census techniques, a handbook. Cambridge, UK: Cambridge University Press.Google Scholar
Thomas, L., Buckland, S. T., Rexstad, E. A., Laake, J. L., Strindberg, S., Hedley, S. L., Bishop, J. R. B., Marques, T. A. and Burnham, K. P. (2010). Distance software: design and analysis of distance sampling surveys for estimating population size. J. Appl. Ecol. 47: 5-14.CrossRefGoogle ScholarPubMed
Tucker, G. M. and Evans, M. I. (1997) Habitats for birds in Europe: a conservation strategy for the wider environment. Cambridge, UK: BirdLife International. (BirdLife Conservation Series no.6).Google Scholar
Wilkinson, D. M. (1999) The disturbing history of intermediate disturbance. Oikos 84: 145-147 CrossRefGoogle Scholar