Effect of population density on diet composition and dietary niche breadth of guanaco (Lama guanicoe, Müller 1776) in northeastern Patagonian steppes
The optimal foraging theory postulates that as animal population density increases, the progressive decline in preferred forage availability results in changes in diet composition and widening of dietary niche breadth. For sedentary guanaco populations, some authors proposed a mechanism of populatio...
| Autores principales: | , , , , |
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| Formato: | info:ar-repo/semantics/artículo |
| Lenguaje: | Inglés |
| Publicado: |
Elsevier
2019
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| Materias: | |
| Acceso en línea: | http://hdl.handle.net/20.500.12123/6512 https://www.sciencedirect.com/science/article/pii/S0140196318307675 https://doi.org/10.1016/j.jaridenv.2019.104000 |
| _version_ | 1855035689358327808 |
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| author | Rodriguez, María Victoria Marino, Andrea Ivana Borrelli, Laura Beatriz Bay Gavuzzo, Alhue Pazos, Gustavo Enrique |
| author_browse | Bay Gavuzzo, Alhue Borrelli, Laura Beatriz Marino, Andrea Ivana Pazos, Gustavo Enrique Rodriguez, María Victoria |
| author_facet | Rodriguez, María Victoria Marino, Andrea Ivana Borrelli, Laura Beatriz Bay Gavuzzo, Alhue Pazos, Gustavo Enrique |
| author_sort | Rodriguez, María Victoria |
| collection | INTA Digital |
| description | The optimal foraging theory postulates that as animal population density increases, the progressive decline in preferred forage availability results in changes in diet composition and widening of dietary niche breadth. For sedentary guanaco populations, some authors proposed a mechanism of population density limitation below the environmental carrying capacity, mediated through territoriality. Under the optimal foraging theory, increased density would lead to changes in guanaco diet selectivity and composition. Conversely, under the self-regulation hypothesis, guanacos would not affect preferred forage availability and no differences in guanaco diet would be expected. We tested these contrasting hypotheses by assessing both the differences in the proportion of grasses
and shrubs present in guanaco diet and dietary niche breadth at three contrasting densities in northeastern Patagonian steppes. We did not find guanaco density effects on preferred forage availability, grass-shrub proportions in the diet and diet selectivity. Guanacos showed a mixed diet composed by plant species of both high and low nutritional quality independently of population density. The lack of changes in diet composition suggests that guanacos did not perceive a restriction in forage availability in terms of either biomass or nutritional content, regardless the observed increase in population density. |
| format | info:ar-repo/semantics/artículo |
| id | INTA6512 |
| institution | Instituto Nacional de Tecnología Agropecuaria (INTA -Argentina) |
| language | Inglés |
| publishDate | 2019 |
| publishDateRange | 2019 |
| publishDateSort | 2019 |
| publisher | Elsevier |
| publisherStr | Elsevier |
| record_format | dspace |
| spelling | INTA65122019-12-13T17:53:07Z Effect of population density on diet composition and dietary niche breadth of guanaco (Lama guanicoe, Müller 1776) in northeastern Patagonian steppes Rodriguez, María Victoria Marino, Andrea Ivana Borrelli, Laura Beatriz Bay Gavuzzo, Alhue Pazos, Gustavo Enrique Guanaco Nutrición Animal Preferencias Alimentarias Densidad de la Población Herbívoros Guanacos Animal Nutrition Feeding Preferences Population Density Herbivores Preferencia de Forrajes Región Patagónica The optimal foraging theory postulates that as animal population density increases, the progressive decline in preferred forage availability results in changes in diet composition and widening of dietary niche breadth. For sedentary guanaco populations, some authors proposed a mechanism of population density limitation below the environmental carrying capacity, mediated through territoriality. Under the optimal foraging theory, increased density would lead to changes in guanaco diet selectivity and composition. Conversely, under the self-regulation hypothesis, guanacos would not affect preferred forage availability and no differences in guanaco diet would be expected. We tested these contrasting hypotheses by assessing both the differences in the proportion of grasses and shrubs present in guanaco diet and dietary niche breadth at three contrasting densities in northeastern Patagonian steppes. We did not find guanaco density effects on preferred forage availability, grass-shrub proportions in the diet and diet selectivity. Guanacos showed a mixed diet composed by plant species of both high and low nutritional quality independently of population density. The lack of changes in diet composition suggests that guanacos did not perceive a restriction in forage availability in terms of either biomass or nutritional content, regardless the observed increase in population density. Estación Experimental Agropecuaria Bariloche Fil: Rodriguez, María Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto Patagónico para el Estudio de los Ecosistemas Continentales; Argentina Fil: Marino, Andrea Ivana. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto Patagónico para el Estudio de los Ecosistemas Continentales; Argentina Fil: Borrelli, Laura Beatriz. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bariloche; Argentina Fil: Bay Gavuzzo, Alhue. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Bariloche; Argentina Fil: Pazos, Gustavo Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto Patagónico para el Estudio de los Ecosistemas Continentales. Universidad Nacional de la Patagonia San Juan Bosco; Argentina 2019-12-13T17:46:27Z 2019-12-13T17:46:27Z 2019-11 info:ar-repo/semantics/artículo info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion http://hdl.handle.net/20.500.12123/6512 https://www.sciencedirect.com/science/article/pii/S0140196318307675 0140-1963 https://doi.org/10.1016/j.jaridenv.2019.104000 eng info:eu-repo/semantics/restrictedAccess application/pdf Elsevier Journal of Arid Environments 170 : 104000 (November 2019) |
| spellingShingle | Guanaco Nutrición Animal Preferencias Alimentarias Densidad de la Población Herbívoros Guanacos Animal Nutrition Feeding Preferences Population Density Herbivores Preferencia de Forrajes Región Patagónica Rodriguez, María Victoria Marino, Andrea Ivana Borrelli, Laura Beatriz Bay Gavuzzo, Alhue Pazos, Gustavo Enrique Effect of population density on diet composition and dietary niche breadth of guanaco (Lama guanicoe, Müller 1776) in northeastern Patagonian steppes |
| title | Effect of population density on diet composition and dietary niche breadth of guanaco (Lama guanicoe, Müller 1776) in northeastern Patagonian steppes |
| title_full | Effect of population density on diet composition and dietary niche breadth of guanaco (Lama guanicoe, Müller 1776) in northeastern Patagonian steppes |
| title_fullStr | Effect of population density on diet composition and dietary niche breadth of guanaco (Lama guanicoe, Müller 1776) in northeastern Patagonian steppes |
| title_full_unstemmed | Effect of population density on diet composition and dietary niche breadth of guanaco (Lama guanicoe, Müller 1776) in northeastern Patagonian steppes |
| title_short | Effect of population density on diet composition and dietary niche breadth of guanaco (Lama guanicoe, Müller 1776) in northeastern Patagonian steppes |
| title_sort | effect of population density on diet composition and dietary niche breadth of guanaco lama guanicoe muller 1776 in northeastern patagonian steppes |
| topic | Guanaco Nutrición Animal Preferencias Alimentarias Densidad de la Población Herbívoros Guanacos Animal Nutrition Feeding Preferences Population Density Herbivores Preferencia de Forrajes Región Patagónica |
| url | http://hdl.handle.net/20.500.12123/6512 https://www.sciencedirect.com/science/article/pii/S0140196318307675 https://doi.org/10.1016/j.jaridenv.2019.104000 |
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