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1.
PLoS One ; 18(7): e0288115, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37494325

RESUMO

Crop loss to wildlife, particularly elephants, threatens livelihoods and support for conservation around many protected areas in Africa and Asia. Low-cost elephant barriers have been successfully deployed in savannas but seldom tested around isolated forest parks where the stakes are high for local farmers and isolated elephant populations. We measured the effectiveness of a series of ≥3 m deep trenches dug by farmers neighboring Kibale National Park, Uganda. We monitored trench quality and crop loss to elephants weekly for a year across 47 transects in four park-adjacent communities, and conducted controlled, before-and-after comparisons of verified damage. Elephants damaged or destroyed >4 ha of crops during 48 independent foraging events, the majority <220m from the forest boundary. The frequency of damage varied significantly between and within communities. The majority of trenches were not breached by elephants but five suffered ≥4 breaches. Elephant-breached trenches and their neighboring trenches were lower quality than those not breached in the same week (Wilcoxon test: p<0.001). Trenches were also more likely to be breached where people had planted more crops favored by elephants (Wilcoxon test: p = 0.014). Thus, trench quality and the draw of palatable crops both appeared to influence elephant damage. Although trenches may deter elephants, challenges include heavy labor and difficulties of digging in rocky and swampy areas. Trenches alone will not prevent conflict but this strategy holds promise for hot-spots of conflict at forest edges. Given the stakes for farmers and biodiversity, we call for systematic assessment of crop losses and offer recommendations on monitoring and analysis. Such data will allow for stronger inference about effectiveness before investment of effort and resources in interventions.


Assuntos
Elefantes , Animais , Uganda , Parques Recreativos , Conservação dos Recursos Naturais , Florestas , Produtos Agrícolas
2.
Sci Total Environ ; 891: 164324, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37230363

RESUMO

Free-roaming dogs are an important concern for public health, livestock production and the environment. Human behaviors-such as allowing pets to roam, abandoning dogs, or feeding stray animals-could influence free-roaming dog abundance and the frequency of occurrence of dog-caused problems. Here we aim to determine patterns of free-roaming dog abundance in urban and rural areas, to reveal spatial variation in human behaviors underlying the free-roaming dog problem, and to test for associations between free-roaming dog abundance and related problems. We conducted our study in Chile, where dogs are a major environmental issue. In Chile, as in many other Global South countries, many people leave their dogs to roam, partly due to norms and to lax enforcement of dog control laws. To address our objectives, we counted dogs in 213 transects in urban and rural areas to model dog abundance using N-mixture models. Then we conducted interviews in 553 properties around the transects to determine people's dog management, their behavior towards free-roaming dogs and the prevalence of dog-caused problems. Dog abundance was higher in transects where a higher number of owned dogs was allowed to roam, as well as in lower-income neighborhoods (based on property tax valuation). Meanwhile, rural citizens were more likely to let their dogs' roam. Dog abandonment was reported more frequently in lower-income urban neighborhoods and rural areas. Not surprisingly, we found that several problems-such as dog bites-were more frequent where we detected more free-roaming dogs. Our results highlight that the owned dog population is a central component of the free-roaming dog problem, and that human behavior is the key driver underlying the problem. Dog management programs should promote responsible dog-ownership, with a strong message focused on keeping dogs inside properties and preventing abandonment.


Assuntos
Animais Selvagens , Gado , Animais , Humanos , Cães , Chile/epidemiologia , Causalidade , Propriedade
3.
World Dev ; 136: 105124, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32834395

RESUMO

Payments for Ecosystem Services (PES) are now a prominent policy instrument for conserving tropical forests. PES are voluntary, direct, and contractual: an ES buyer pays an ES steward for adopting conservation practices for a fixed term. A defining feature of PES is its 'quid pro quo' conditionality, e.g. stewards are paid only if they deliver contracted conservation outcomes. Most studies on PES effectiveness focus on the steward's compliance with contract conditions. By contrast, the buyer's compliance has received scant attention despite the fact that PES programs across the globe have delayed payments, suspended re-enrollment, or shut down altogether. 'Use-restricting' PES depend on the continued flow of funding to pay for conservation; however, institutional, political, and economic factors can disrupt or terminate PES funding. What happens when the PES money unexpectedly runs out? Do stewards continue to conserve or revert to their former practices? We use mixed methods to study equity concerns and forest outcomes of an unexpected, two-year interruption in conservation payments to 63 private landowners residing in Ecuador's Amazon and enrolled in the Socio Bosque program, compared to similar landowners who did not enroll. Using quasi-experimental methods, we found that during the payment suspension period enrolled properties did not maintain their conservation outcomes where deforestation pressures were high (e.g. close to roads). Where deforestation pressures were low, enrolled properties continued to conserve more, on average, than similar properties not enrolled. Findings from 40 interviews and 26 focus groups conducted before, during, and after the payment suspension exposed profound landowner uncertainty regarding their contract rights. Poor official communication and imbalanced PES contract terms reinforced power inequalities between the state and rural ES stewards. Our work highlights the need to plan for financial volatility and to protect participants' rights in PES contract design.

4.
Science ; 364(6443): 832-833, 2019 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-31147509
5.
J Environ Manage ; 229: 67-75, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30143314

RESUMO

Free-ranging dogs (Canis familiaris) significantly threaten wildlife, including endangered species. Although this problem resembles threats from other invasive animals, managing roaming dogs is even more fraught due to their close association with humans. Here we use interviews (n = 166) to document patterns of dog ownership and care and to measure public attitudes toward management strategies to control free-roaming dogs that threaten wildlife in rural areas of southern Chile. We compare attitudes toward lethal control and fines in scenarios where dogs attack livestock, children or wild animals or enter protected areas. We also test for variation in attitudes according to gender, age, education and proximity to urban areas. Most respondents (98.1%) opposed lethal control for at least one scenario and they were more likely to accept killing dogs that attacked sheep than those attacking wildlife. Similarly, support for fines was higher when dogs attacked livestock or people versus wild animals. Respondents consistently favored fining the owner over eliminating the problem dog. When asked about their management preferences, many respondents indicated that the movement of problem dogs-including to a lesser extent those threatening wildlife-should be restricted. However, in practice most dog-owners allowed one or more of their dogs to move freely at least part of the time. Finally, the wildlife species of concern mattered, e.g. 40% thought no action was necessary when dogs attack foxes, but this dropped to 12% for pudu (a small deer). In sum, participants had significantly more concern for livestock and human safety than for wildlife protection. We close by discussing management and policy implications.


Assuntos
Animais Selvagens , Cães , Opinião Pública , Animais , Chile , Feminino , Humanos , Gado , Masculino , Propriedade , Ovinos
7.
Environ Manage ; 58(2): 297-311, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27179802

RESUMO

Many researchers have tested whether protected areas save tropical forest, but generally focus on parks and reserves, management units that have internationally recognized standing and clear objectives. Buffer zones have received considerably less attention because of their ambiguous rules and often informal status. Although buffer zones are frequently dismissed as ineffective, they warrant attention given the need for landscape-level approaches to conservation and their prevalence around the world-in Peru, buffer zones cover >10 % of the country. This study examines the effectiveness of buffer zones in the Peruvian Amazon to (a) prevent deforestation and (b) limit the extent of mining concessions. We employ covariate matching to determine the impact of 13 buffer zones on deforestation and mining concessions from 2007 to 2012. Despite variation between sites, these 13 buffer zones have prevented ~320 km(2) of forest loss within their borders during the study period and ~1739 km(2) of mining concessions, an outcome associated with the special approval process for granting formal concessions in these areas. However, a closer look at the buffer zone around the Tambopata National Reserve reveals the difficulties of controlling illegal and informal activities. According to interviews with NGO employees, government officials, and community leaders, enforcement of conservation is limited by uncertain institutional responsibilities, inadequate budgets, and corruption, although formal and community-based efforts to block illicit mining are on the rise. Landscape-level conservation not only requires clear legal protocol for addressing large-scale, formal extractive activities, but there must also be strategies and coordination to combat illegal activities.


Assuntos
Conservação dos Recursos Naturais , Florestas , Mineração , Conservação dos Recursos Naturais/legislação & jurisprudência , Conservação dos Recursos Naturais/métodos , Órgãos Governamentais , Regulamentação Governamental , Mineração/legislação & jurisprudência , Indústria de Petróleo e Gás , Peru
8.
Conserv Biol ; 28(3): 851-60, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24527992

RESUMO

Lion (Panthera leo) populations are in decline throughout most of Africa. The problem is particularly acute in southern Kenya, where Maasai pastoralists have been spearing and poisoning lions at a rate that will ensure near term local extinction. We investigated 2 approaches for improving local tolerance of lions: compensation payments for livestock lost to predators and Lion Guardians, which draws on local cultural values and knowledge to mitigate livestock-carnivore conflict and monitor carnivores. To gauge the overall influence of conservation intervention, we combined both programs into a single conservation treatment variable. Using 8 years of lion killing data, we applied Manski's partial identification approach with bounded assumptions to investigate the effect of conservation treatment on lion killing in 4 contiguous areas. In 3 of the areas, conservation treatment was positively associated with a reduction in lion killing. We then applied a generalized linear model to assess the relative efficacy of the 2 interventions. The model estimated that compensation resulted in an 87-91% drop in the number of lions killed, whereas Lion Guardians (operating in combination with compensation and alone) resulted in a 99% drop in lion killing.


Assuntos
Conservação dos Recursos Naturais/métodos , Leões , Animais , Conservação dos Recursos Naturais/economia , Cultura , Quênia , Modelos Lineares
9.
Environ Manage ; 52(6): 1320-32, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24026255

RESUMO

Crop and livestock losses to wildlife are a concern for people neighboring many protected areas (PAs) and can generate opposition to conservation. Examining patterns of conflict and associated tolerance is important to devise policies to reduce conflict impacts on people and wildlife. We surveyed 398 households from 178 villages within 10 km of Ranthambore, Kanha, and Nagarahole parks in India. We compared different attitudes toward wildlife, and presented hypothetical response scenarios, including killing the problem animal(s). Eighty percent of households reported crop losses to wildlife and 13 % livestock losses. Higher crop loss was associated with more cropping months per year, greater crop variety, and more harvest seasons per year but did not vary with proximity to the PA, suggesting that PAs are not necessarily "sources" for crop raiders. By contrast, complaints of "depredating carnivores" were associated with people-grazing animals and collecting resources from PAs. Many households (83 %) engaged in mitigation efforts. We found that only fencing and guard animals reduce crop losses, and no efforts to lower livestock losses. Contrary to our expectations, carnivores were not viewed with more hostility than crop-raiding wildlife. Households reported greater inclination to kill herbivores destroying crops or carnivores harming people, but not carnivores preying on livestock.Our model estimated probability of [corrected] crop loss was 82 % across surveyed households (highest in Kanha),while the livestock loss experienced was 27 % (highest in Ranthambore). Our comparative study provides insights into factors associated with conflict loss and tolerance, and aids in improving ongoing conservation and compensation efforts.


Assuntos
Agricultura/estatística & dados numéricos , Animais Selvagens , Conservação dos Recursos Naturais/métodos , Adulto , Animais , Carnívoros/fisiologia , Conservação dos Recursos Naturais/estatística & dados numéricos , Feminino , Herbivoria/fisiologia , Humanos , Índia , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Comportamento Predatório/fisiologia , Opinião Pública
10.
Conserv Biol ; 27(2): 315-23, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23293913

RESUMO

Understanding individual attitudes and how these predict overt opposition to predator conservation or direct, covert action against predators will help to recover and maintain them. Studies of attitudes toward wild animals rely primarily on samples of individuals at a single time point. We examined longitudinal change in individuals' attitudes toward gray wolves (Canis lupus). In the contiguous United States, amidst persistent controversy and opposition, abundances of gray wolves are at their highest in 60 years. We used mailed surveys to sample 1892 residents of Wisconsin in 2001 or 2004 and then resampled 656 of these individuals who resided in wolf range in 2009. Our study spanned a period of policy shifts and increasing wolf abundance. Over time, the 656 respondents increased agreement with statements reflecting fear of wolves, the belief that wolves compete with hunters for deer (Odocoileus virginianus), and inclination to poach a wolf. Endorsement of lethal control of wolves by the state and public hunting of wolves also increased. Neither the time span over which respondents reported exposure to wolves locally nor self-reported losses of domestic animals to wolves correlated with changes in attitude. We predict future increases in legal and illegal killing of wolves that may reduce their abundance in Wisconsin unless interventions are implemented to improve attitudes and behavior toward wolves. To assess whether interventions change attitudes, longitudinal studies like ours are needed. Análisis Longitudinal de las Actitudes Hacia Lobos.


Assuntos
Atitude , Conservação dos Recursos Naturais , Lobos , Animais , Feminino , Humanos , Estudos Longitudinais , Masculino , Inquéritos e Questionários , Wisconsin
11.
Proc Natl Acad Sci U S A ; 108(34): 13919-24, 2011 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-21873178

RESUMO

We use field data linked to satellite image analysis to examine the relationship between biodiversity loss, deforestation, and poverty around Kibale National Park (KNP) in western Uganda, 1996-2006. Over this decade, KNP generally maintained forest cover, tree species, and primate populations, whereas neighboring communal forest patches were reduced by half and showed substantial declines in tree species and primate populations. However, a bad decade for forest outside the park proved a prosperous one for most local residents. Panel data for 252 households show substantial improvement in welfare indicators (e.g., safer water, more durable roof material), with the greatest increases found among those with highest initial assets. A combination of regression analysis and matching estimators shows that although the poor tend to be located on the park perimeter, proximity to the park has no measureable effect on growth of productive assets. The risk for land loss among the poor was inversely correlated with proximity to the park, initial farm size, and decline in adjacent communal forests. We conclude the current disproportionate presence of poor households at the edge of the park does not signal that the park is a poverty trap. Rather, Kibale appears to provide protection against desperation sales and farm loss among those most vulnerable.


Assuntos
Conservação dos Recursos Naturais/economia , Ecossistema , Pobreza/economia , Árvores/crescimento & desenvolvimento , Características da Família , Geografia , Fatores de Tempo , Uganda
12.
Am J Primatol ; 62(2): 55-69, 2004 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-14983464

RESUMO

Understanding the determinants of animal abundance has become more vital as ecologists are increasingly asked to apply their knowledge to the construction of informed management plans. However, there are few general models are available to explain variation in abundance. Some notable exceptions are studies of folivorous primates, in which the protein-to-fiber ratio of foods has been shown to predict biomass. Here we examine the generality of Milton's [American Naturalist 114:363-378, 1979] protein/fiber model by providing a detailed analysis of diet selection in black-and-white colobus monkeys (Colobus guereza), and applying the model to populations shown to be stable; an assumption not previously examined. Based on observations of two groups of black-and-white colobus in Kibale National Park, Uganda, and one group in a forest fragment, we documented that the animals selected young leaves that had more protein, were more digestible, and had a higher protein-to-fiber ratio than mature leaves. The mature leaves did not differ from young leaves with respect to secondary compounds or mineral content (with the exceptions of copper and zinc). All of the colobus groups selected foods with a high protein-to-fiber ratios. However, one group also selected more digestible foods, and in another group, foraging efforts were positively related to zinc and negatively related to potassium. Previous studies that examined Milton's protein/fiber model did not demonstrate that the study populations were stable. If some populations were not at carrying capacity, then the correlations drawn between food availability and/or quality and folivore biomass may have been spurious. To address this issue, we censused a series of forest fragments in 1995 and again in 2000. We found that the populations in these fragments had declined from 165 in 1995 to 119 animals in 2000. However, based on evidence of population stability and lack of forest disturbance, we concluded that five of the original populations were stable. The biomass of these populations was related to the protein-to-fiber ratio of the fragment's trees. Combining our data with published data, we demonstrate that the protein-to-fiber ratios of mature leaves available to these folivorous primates accounted for 87% of the variance in their biomass.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Biomassa , Colobus/fisiologia , Comportamento Alimentar/fisiologia , Modelos Biológicos , Análise de Variância , Animais , Fibras na Dieta , Proteínas Alimentares , Dinâmica Populacional , Oligoelementos , Árvores , Uganda
13.
Ambio ; 32(4): 269-74, 2003 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12956592

RESUMO

Amazonian deforestation rates vary regionally, and ebb and flow according to macroeconomic policy and local social factors. We used remote sensing and field interviews to investigate deforestation patterns and drivers at a Peruvian frontier during 1986-1991, when rural credit and guaranteed markets were available; and 1991-1997, when structural adjustment measures were imposed. The highest rate of clearing (1.5% gross) was observed along roads during 1986-1991. Roadside deforestation slowed in 1991-1997 (0.7% gross) and extensive regrowth yielded a net increase in forest cover (0.5%). Deforestation along rivers was relatively constant. Riverside farms today retain more land in both crops and forest than do roadside farms where pasture and successional growth predominate. Long-term residents maintain more forest on their farms than do recent colonists, but proximity to urban markets is the strongest predictor of forest cover. Future credit programs must reflect spatial patterns of development and ecological vulnerability, and support the recuperation of fallow lands and secondary forest.


Assuntos
Agricultura/estatística & dados numéricos , Conservação dos Recursos Naturais/estatística & dados numéricos , Ecossistema , Árvores/crescimento & desenvolvimento , Análise de Variância , Monitoramento Ambiental , Peru , Política Pública , Fatores Socioeconômicos , Astronave , Estatísticas não Paramétricas , Clima Tropical
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