Management of Free-Roaming Horses Cassandra M.V
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Natural Resource Ecology and Management Natural Resource Ecology and Management Publications 2016 Management of Free-Roaming Horses Cassandra M.V. Nuñez Iowa State University, [email protected] Alberto Scorolli Universidad Nacional del Sur Laura Lagos Universidad de Santiago de Compostela David Berman Australian Wild Horse Management Services Albert J. Kane U.S. Department of Agriculture Follow this and additional works at: https://lib.dr.iastate.edu/nrem_pubs Part of the Natural Resources and Conservation Commons, Natural Resources Management and Policy Commons, and the Terrestrial and Aquatic Ecology Commons The ompc lete bibliographic information for this item can be found at https://lib.dr.iastate.edu/ nrem_pubs/280. For information on how to cite this item, please visit http://lib.dr.iastate.edu/ howtocite.html. This Book Chapter is brought to you for free and open access by the Natural Resource Ecology and Management at Iowa State University Digital Repository. It has been accepted for inclusion in Natural Resource Ecology and Management Publications by an authorized administrator of Iowa State University Digital Repository. For more information, please contact [email protected]. Management of Free-Roaming Horses Abstract The modern horse (Equus caballus) evolved in North America about four million years ago, dispersing into Eurasia approximately two to three million years ago. Following this emigration, several extinctions occurred in North America, as did additional migrations to Asia and return migrations to North America (see chap. 8). The final North American extinction occurred between 13,000 and 11,000 years ago (Hunt 1992). Eurasian populations persisted, and humans began domestication ~6,000-5 ,500 years ago (Outram et al. 2009) on the western Eurasian Steppe (Warmuth et al. 2012) and perhaps on the Iberian Peninsula (Warmuth et al. 2011; Achilli et al. 2012). Today, European free-roaming horse populations can be grouped into three classes: (1) traditional popu· lations, (2) true feral populations, and (3) introduced populations (for the purposes of conservation management). We consider traditional popu· lations to be free-roaming, long-established horses that are harvested by local people (United Kingdom, Spain, Portugal). Atlantic ponies from the North Iberian Peninsula and the North Atlantic Islands make up a large proportion of these animals; some consider them remnants of wild horses living in the region since the Pleistocene (Barcena 2012). Feral populations are domestic animals that were abandoned by local farmers and today live largely unmanaged (Romania, Russia), and introduced populations are used as components of various habitat restoration proj· ects across Europe (Latvia, the Netherlands) (Rewilding Europe 2012). In North America, horses reintroduced in 1493 spread across the plains after escape or release, forming feral herds throughout the United States and Canada (see chap. 8). In South America, horses introduced by the Spanish and Portuguese during the sixteenth century spread north into the Pampas, Patagonia, and the mountainous Andean regions. And in Australia, horses introduced by European settlers in 1787 spread into the hills around Sydney and into the north, west, and south as pastoral settlement spread across the continent (see chap. 8). In more recent history, the extirpation of their natural predators has led to even further feral horse expansion, resulting in increased human conflict as feral horses more heavily affected livestock, industry, and native wildlife. Disciplines Natural Resources and Conservation | Natural Resources Management and Policy | Terrestrial and Aquatic Ecology Comments This is a chapter from Nuñez, C.M.V., A. Scorolli, L. Lagos, D. Berman, A. Kane. 2016. Management of freeroaming horses in J.I. Ransom and P. Kaczensky, eds. Wild Equids. The oJ hns Hopkins University Press. Rights Works produced by employees of the U.S. Government as part of their official duties are not copyrighted within the U.S. The onc tent of this document is not copyrighted. This book chapter is available at Iowa State University Digital Repository: https://lib.dr.iastate.edu/nrem_pubs/280 Management of Free-Roaming Horses CASSANDRA M.V. NUNEZ, ALBERTO SCOROLLI, LAURA LAGOS, DAVID BERMAN, AND ALBERT J. KANE he modern horse (Equus caballus) evolved in North America about Tfour million years ago, dispersing into Eurasia approximately two to three million years ago. Following this emigration, several extinc tions occurred in North America, as did additional migrations to Asia and return migrations to North America (see chap. 8). The final North American extinction occurred between 13,000 and 11,000 years ago (Hunt 1992). Eurasian populations persisted, and humans began domes tication ~6,000-5 ,500 years ago (Outram et al. 2009) on the western Eur asian Steppe (Warmuth et al. 2012) and perhaps on the Iberian Peninsula (Warmuth et al. 2011; Achilli et al. 2012). Today, European free-roaming horse populations can be grouped into three classes: (1) traditional popu· lations, (2) true feral populations, and (3) introduced populations (for the purposes of conservation management). We consider traditional popu· lations to be free-roaming, long-established horses that are harvested by local people (United Kingdom, Spain, Portugal). Atlantic ponies from the North Iberian Peninsula and the North Atlantic Islands make up a large proportion of these animals; some consider them remnants of wild horses living in the region since the Pleistocene (Barcena 2012). Feral populations are domestic animals that were abandoned by local farmers and today live largely unmanaged (Romania, Russia), and introduced populations are used as components of various habitat restoration proj· ects across Europe (Latvia, the Netherlands) (Rewilding Europe 2012). In North America, horses reintroduced in 1493 spread across the plains after escape or release, forming feral herds throughout the United States and Canada (see chap. 8). In South America, horses introduced by the Spanish and Portuguese during the sixteenth century spread north into the Pampas, Patagonia, and the mountainous Andean regions. And in Australia, horses introduced by European settlers in 1787 spread into the hills around Sydney and into the north, west, and south as pastoral settle ment spread across the continent (see chap. 8). In more recent history, the extirpation of their natural predators has led to even further feral horse expansion, resulting in increased human conflict as feral horses more heavily affected livestock, industry, and native wildlife. In this chapter, we focus on the management of free-roaming horse populations occurring in different parts of the United States, South America (in Argentina), Europe (in the United Kingdom, Portugal, Spain, the Netherlands, Romania, and Russia), and Australia (in the Northern 134 History and Management Number of individuals • < 100 • 101 -1,000 • 1,001-10,000 • 10,001-100,000 e populations considered in this chapter O documented populations not considered in this chapter Fig. 10.1 The distribution of feral horse populations in the United States (A), South America (8), Europe (C), and Australia• (D). So lid circles represent the populations discussed in this chapter; open circles represent documented populations that are not discussed. Circle size denotes the estimated number of feral horses in the different populations. Sources: (A) Rubenstein and Nunez 2009, BLM 2013b, North Carolina Coastal Reserve and National Estuarine Research Reserve 2013, National Park Service 2013, Southern States 2013, Ransom et of. 2014a; (B) Pacheco and Herrera 1997, Scorolli and Zoratti 2007, Walton 2008, Scorolli and Lopez Cazorla 2010; (C) Iglesia 1973, Murphy and Gonzalez Faraco 2002, Prieditis 2002, Dartmoor Park Authority 2006, Leblond eta/. 2007, Tupac-Yupanqui eta/. 2011, Matos Vieira Leite 2012, Verderers of the New Forest 2013, Winton eta/. 2013, M. Brewer, unpublished data, M. lnza, unpublished data, L. Lorenzo, unpublished data, 0 . Rosu , unpublished data, Roztocze National Park, unpublished data, N. Spasskaya, unpublished data, van Dierendonck, unpublished data; (D) Dobbie eta/. 1993 Territory) (fig. 10.1). The management strategies em ployed in different countries are largely dependent Ecological and Human Conflict upon local laws, logistics, public opinion, the specific Around the world, free -roaming horses can adversely challenges horses pose in an area, and on the social affect the local ecology. In Australia, for example, and cultural importance of free-roaming horses. Sig where there are no natural predators, feral horses can nificant variation in management policy exists, and de have particularly detrimental impacts, including the pending on where they occur, horse populations are alteration of bird community composition; declines treated differently. Here we discuss human interven in reptile and amphibian abundance; soil loss, compac tion with free-roaming horses in different regions as tion, and erosion; vegetation trampling; reduction in case studies of the various management options avail plant biodiversity; tree death; damage to bog habitats able. Several strategies are explored; however, what is and waterholes; and the expansion of invasive weeds feasible or acceptable often varies depending on the (Nimmo and Miller 2007). region, and our ability to effectively control popula Feral horses can have similar impacts in other areas tions with certain methods has not been sufficiently