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1.
Ecosyst People (Abingdon) ; 17(1): 400-410, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34396139

RESUMEN

We studied food security and biodiversity conservation from a social-ecological perspective in southwestern Ethiopia. Specialist tree, bird, and mammal species required large, undisturbed forest, supporting the notion of 'land sparing' for conservation. However, our findings also suggest that forest areas should be embedded within a multifunctional landscape matrix (i.e. 'land sharing'), because farmland also supported many species and ecosystem services and was the basis of diversified livelihoods. Diversified livelihoods improved smallholder food security, while lack of access to capital assets and crop raiding by wild forest animals negatively influenced food security. Food and biodiversity governance lacked coordination and was strongly hierarchical, with relatively few stakeholders being highly powerful. Our study shows that issues of livelihoods, access to resources, governance and equity are central when resolving challenges around food security and biodiversity. A multi-facetted, social-ecological approach is better able to capture such complexity than the conventional, two-dimensional land sparing versus sharing framework.

2.
Environ Manage ; 67(4): 717-730, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33591406

RESUMEN

Ensuring food security while also protecting biodiversity requires a governance system that can address intra- and intersectoral complexity. In this paper, we sought to explore the governance challenges surrounding food security and biodiversity conservation through an empirical study in Jimma zone, southwestern Ethiopia. We used bottom-up snowball sampling to identify stakeholders and then held semi-structured interviews with 177 stakeholders across multiple levels of governance. We also conducted 24 focus group discussions with local people. Data were transcribed and thematically analyzed for its contents. Challenges in the structure of institutions and policy incoherence were the key challenges identified for the governance of food security and biodiversity conservation. The challenges around institutional structure included incompatibilities of the nature of governing institutions with the complexity inherent within and between the two sectors examined. Incoherences in policy goals, instruments, and contradictions of policy output relative to the actual problems of food security and biodiversity further hampered effective governance of food security and biodiversity conservation. Notably, many of the challenges that influenced an individual sector also posed a challenge for the integrated governance of food security and biodiversity conservation, often in a more pronounced way. Based on our findings, we argue that governance in our case study area requires a more integrated and collaborative approach that pays attention to institutional interplay in order to ensure institutional fit and consistency across policy goals.


Asunto(s)
Conservación de los Recursos Naturales , Seguridad Alimentaria , Biodiversidad , Etiopía , Humanos
3.
Food Secur ; 11(1): 167-181, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30931047

RESUMEN

Households combine capital assets in a process involving human agency and resourcefulness to construct livelihood strategies and generate well-being outcomes. Here, we (1) characterized types of livelihood strategies; (2) determined how different capital assets are associated with different livelihood strategies; and (3) determined how livelihood strategies differed in food security outcomes. We conducted a survey in southwestern Ethiopia and used principal component and cluster analyses. Five types of livelihood strategies, which differed mainly in food and cash crops comprising the strategy, were identified. These were, in order of decreasing food security: 'three food crops, coffee and khat', n = 68; 'three food crops and khat', n = 59; 'two food crops, coffee and khat', n = 78; 'two food crops and khat', n = 88; and 'one food crop, coffee and khat', n = 44. The livelihood strategy 'three food crops, coffee and khat' was associated with a wide range of capital assets, particularly having larger aggregate farm field size and learning from other farmers. A generalized linear model showed that livelihood strategies were significantly associated with food security outcomes. Particularly, a high number of food crops in a strategy was linked with relatively high food security. In this context, diversified livelihood strategies primarily through having a mix of food crops for subsistence, in combination with cash crops for income, are important for food security. This suggests a need to rethink dominant policy narratives, which have a narrow focus on increasing productivity and commercialization as the primary pathway to food security.

4.
Conserv Lett ; 11(3): e12429, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30034527

RESUMEN

Agricultural land use is a key interface between the goals of ensuring food security and protecting biodiversity. "Land sparing" supports intensive agriculture to save land for conservation, whereas "land sharing" integrates production and conservation on the same land. The framing around sparing versus sharing has been extensively debated. Here, we focused on a frequently missing yet crucial component, namely the governance dimension. Through a case-study in Ethiopia, we uncovered stakeholder preferences for sparing versus sharing, the underlying rationale, and implementation capacity challenges. Policy stakeholders preferred sparing whereas implementation stakeholders preferred sharing, which aligned with existing informal institutions. Implementation of both strategies was limited by social, biophysical, and institutional factors. Land use policies need to account for both ecological patterns and social context. The findings from simple analytical frameworks (e.g., sparing vs. sharing) therefore need to be interpreted carefully, and in a social-ecological context, to generate meaningful recommendations for conservation practice.

6.
Trends Ecol Evol ; 32(5): 335-345, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28284373

RESUMEN

Given the serious limitations of production-oriented frameworks, we offer here a new conceptual framework for how to analyze the nexus of food security and biodiversity conservation. We introduce four archetypes of social-ecological system states corresponding to win-win (e.g., agroecology), win-lose (e.g., intensive agriculture), lose-win (e.g., fortress conservation), and lose-lose (e.g., degraded landscapes) outcomes for food security and biodiversity conservation. Each archetype is shaped by characteristic external drivers, exhibits characteristic internal social-ecological features, and has characteristic feedbacks that maintain it. This framework shifts the emphasis from focusing on production only to considering social-ecological dynamics, and enables comparison among landscapes. Moreover, examining drivers and feedbacks facilitates the analysis of possible transitions between system states (e.g., from a lose-lose outcome to a more preferred outcome).


Asunto(s)
Agricultura , Biodiversidad , Conservación de los Recursos Naturales , Abastecimiento de Alimentos , Ecosistema
8.
Proc Biol Sci ; 282(1814)2015 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-26336169

RESUMEN

Apex predators perform important functions that regulate ecosystems worldwide. However, little is known about how ecosystem regulation by predators is influenced by human activities. In particular, how important are top-down effects of predators relative to direct and indirect human-mediated bottom-up and top-down processes? Combining data on species' occurrence from camera traps and hunting records, we aimed to quantify the relative effects of top-down and bottom-up processes in shaping predator and prey distributions in a human-dominated landscape in Transylvania, Romania. By global standards this system is diverse, including apex predators (brown bear and wolf), mesopredators (red fox) and large herbivores (roe and red deer). Humans and free-ranging dogs represent additional predators in the system. Using structural equation modelling, we found that apex predators suppress lower trophic levels, especially herbivores. However, direct and indirect top-down effects of humans affected the ecosystem more strongly, influencing species at all trophic levels. Our study highlights the need to explicitly embed humans and their influences within trophic cascade theory. This will greatly expand our understanding of species interactions in human-modified landscapes, which compose the majority of the Earth's terrestrial surface.


Asunto(s)
Cadena Alimentaria , Actividades Humanas , Conducta Predatoria , Animales , Ciervos , Perros , Zorros , Modelos Teóricos , Dinámica Poblacional , Rumanía , Ursidae , Lobos
10.
Biol Lett ; 10(1): 20130889, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24429681

RESUMEN

Changes in telomere length are believed to reflect changes in physiological state and life expectancy in animals. However, much remains unknown about the determinants of telomere dynamics in wild populations, and specifically the influence of conditions during highly mobile life-history stages, for example migration. We tested whether telomere dynamics were associated with migratory behaviour and/or with stress during reproduction in free-living seabirds. We induced short-term stress during reproduction in chick-rearing, black-legged kittiwakes (Rissa tridactyla), tracked winter migration with geolocators and measured telomere length before and after winter migration. We found that time spent at wintering grounds correlated with reduced telomere loss, while stress during reproduction accelerated telomere shortening. Our results suggest that different life-history stages interact to influence telomere length, and that migratory patterns may be important determinants of variation in an individual's telomere dynamics.


Asunto(s)
Migración Animal , Aves/fisiología , Reproducción , Estrés Fisiológico , Telómero , Animales , Aves/genética
11.
J Exp Biol ; 213(Pt 17): 2958-66, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20709924

RESUMEN

Despite the widespread use of the doubly labelled water (DLW) method in energetic studies of free-ranging animals, effects of the method on study animals are rarely assessed. We studied behavioural effects of two alternative DLW protocols. During two consecutive breeding seasons, 42 parent black-legged kittiwakes received either the commonly used two-sample (TS) or the less invasive single-sample (SS) DLW treatment. A third group served as a non-treated control. We evaluated the effect of treatment with respect to the time birds took to return to their nest after treatment and recaptures, and the nest attendance during DLW measurement periods. We found that TS kittiwakes took on average 20 times longer to return to their nest than SS kittiwakes after initial treatment, and nest attendance was reduced by about 40% relative to control birds. In contrast, nest attendance did not differ between control and SS kittiwakes. Estimates of energy expenditure of SS kittiwakes exceeded those of TS kittiwakes by 15%. This difference was probably caused by TS birds remaining inactive for extended time periods while at sea. Our results demonstrate that the common assumption that the TS DLW method has little impact on the behaviour of study subjects is in some circumstances fallacious. Estimates of energy expenditure derived by the SS approach may thus more accurately reflect unbiased rates of energy expenditure. However, the choice of protocol may be a trade-off between their impact on behaviour, and hence accuracy, and their differences in precision. Adopting procedures that minimize the impact of TS protocols may be useful.


Asunto(s)
Conducta Animal/fisiología , Charadriiformes/fisiología , Metabolismo Energético/fisiología , Marcaje Isotópico/métodos , Agua/metabolismo , Animales , Metabolismo Basal/fisiología , Modelos Lineales , Comportamiento de Nidificación/fisiología , Modelos de Riesgos Proporcionales , Factores de Tiempo
12.
J Anim Ecol ; 79(1): 205-13, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19817918

RESUMEN

1. The rate at which free-living animals can expend energy is limited but the causes of this limitation are not well understood. Theoretically, energy expenditure may be intrinsically limited by physiological properties of the animal constraining its capacity to process energy. Alternatively, the limitation could be set extrinsically by the amount of energy available in the environment or by a fitness trade-off in terms of reduced future survival associated with elevated metabolism. 2. We measured daily energy expenditure (DEE) using the doubly labelled water method in chick-rearing black-legged kittiwakes (Rissa tridactyla) at a study site close to the northern limit of their breeding range over 5 years. We measured breeding success, foraging trip duration and diet composition as proxies of resource availability during these years and estimated the probability of parent kittiwakes to return to the colony in relation to their energy expenditure in order to determine whether kittiwakes adjust their DEE in response to variation in prey availability and whether elevated DEE is associated with a decrease in adult survival. 3. We found that DEE was strikingly similar across all five study years. There was no evidence that energy expenditure was limited by resource availability that varied considerably among study years. Furthermore, there was no evidence of a negative effect of DEE on adult return rate, which does not support the hypothesis of a survival cost connected to elevated energy expenditure. 4. The additional lack of variation in DEE with respect to ambient temperature, brood size or between sexes suggests that kittiwakes at a time of peak energy demands may operate close to an intrinsic metabolic ceiling independent of extrinsic factors.


Asunto(s)
Charadriiformes/fisiología , Metabolismo Energético/fisiología , Animales , Ecosistema , Reproducción/fisiología , Factores de Tiempo
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