title: Effectiveness of fencing and hunting to control Lama guanicoe browsing damage: Implications for Nothofagus pumilio regeneration in harvested forests.
abstract: Browsing damage by native ungulates is often to be considered one of the reasons of regeneration failure in Nothofagus pumilio silvicultural systems. Fencing and hunting in forests at regeneration phase have been proposed to mitigate browsing effects. This study aims to determine effectiveness of these control methods in harvested forests, evaluating browsing damage over regeneration, as well as climate-related constraints (freezing or desiccation). Forest structure and regeneration plots were established in two exclosures against native ungulates (Lama guanicoe) by wire fences in the Chilean portion of Tierra del Fuego island, where tree regeneration density, growth, abiotic damage and quality (multi-stems and base/stem deformation) were assessed. Exclosures did not influence regeneration density (at the initial stage with < 1.3 m high, and at the advanced stage with >1.3 m high). However, sapling height at 10-years old was significantly lower outside (40-50 cm high) than inside exclosures (80-100 cm), and also increased their annual height growth, probably as a hunting effect. Likewise, quality was better inside exclosures. Alongside browsing, abiotic conditions negatively influenced sapling quality in the regeneration phase (20%-28% of all seedlings), but greatly to taller plants (as those from inside exclosure). This highlights the importance of considering climatic factors when analysing browsing effects. For best results, control of guanaco in recently harvested areas by fencing should be applied in combination with a reduction of guanaco density through continuous hunting. The benefits of mitigation actions (fencing and hunting) on regeneration growth may shorten the regeneration phase period in shelterwood cutting forests (30-50% less time), but incremental costs must be analysed in the framework of management planning by means of long-term studies.
authors.affiliation: Centro Austral de Investigaciones Científicas (CADIC) - Agroforestry Resource Laboratory, Houssay 200 (9410) Ushuaia, Tierra del Fuego, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Rivadavia 1917 (1033) Ciudad de Buenos Aires, Buenos Aires, Argentina. Electronic address: gpastur@conicet.gov.ar.
authors.forename: Guillermo
authors.initials: G
authors.lastname: Martínez Pastur
authors.affiliation: Centro Austral de Investigaciones Científicas (CADIC) - Agroforestry Resource Laboratory, Houssay 200 (9410) Ushuaia, Tierra del Fuego, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Rivadavia 1917 (1033) Ciudad de Buenos Aires, Buenos Aires, Argentina.
authors.forename: Rosina
authors.initials: R
authors.lastname: Soler
authors.affiliation: Centro Austral de Investigaciones Científicas (CADIC) - Agroforestry Resource Laboratory, Houssay 200 (9410) Ushuaia, Tierra del Fuego, Argentina.
authors.forename: Horacio
authors.initials: H
authors.lastname: Ivancich
authors.affiliation: Centro Austral de Investigaciones Científicas (CADIC) - Agroforestry Resource Laboratory, Houssay 200 (9410) Ushuaia, Tierra del Fuego, Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Rivadavia 1917 (1033) Ciudad de Buenos Aires, Buenos Aires, Argentina.
authors.forename: María V
authors.initials: MV
authors.lastname: Lencinas
authors.affiliation: INTA EEA Santa Cruz, Mahatma Ghandi 1322 (9400) Río Gallegos, Santa Cruz, Argentina; Universidad Nacional de la Patagonia Austral (UNPA), Lisandro de la Torre 1070 (9400) Río Gallegos, Santa Cruz, Argentina.
authors.forename: Héctor
authors.initials: H
authors.lastname: Bahamonde
authors.affiliation: Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Rivadavia 1917 (1033) Ciudad de Buenos Aires, Buenos Aires, Argentina; INTA EEA Santa Cruz, Mahatma Ghandi 1322 (9400) Río Gallegos, Santa Cruz, Argentina; Universidad Nacional de la Patagonia Austral (UNPA), Lisandro de la Torre 1070 (9400) Río Gallegos, Santa Cruz, Argentina.
authors.forename: Pablo L
authors.initials: PL
authors.lastname: Peri
mesh_terms: D000704:Analysis of Variance; D065136:Animal Culling / Q000379:methods*; D000818:Animals; D002161:Camelids, New World; D002677:Chile; D003247:Conservation of Natural Resources / Q000379:methods*; D016468:Forestry / Q000379:methods*; D065928:Forests; D019684:Magnoliopsida / Q000254:growth & development*; D036226:Seedlings / Q000254:growth & development
keywords: Browsing; Exclosures; Forest harvesting; Plant quality; Regeneration growth; Silviculture