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Stacy A. Lischka Tara L. Teel Heather E. Johnson Courtney Larson Stewart Breck Kevin Crooks 《Conservation biology》2020,34(6):1383-1392
Conflicts between people and wild animals are increasing globally, often with serious consequences for both. Local regulations or ordinances are frequently used to promote human behaviors that minimize these conflicts (risk-reducing behaviors), but compliance with ordinances can be highly variable. While efforts to increase compliance could be improved through applications of conservation psychology, little is known about the relative influence of different factors motivating compliance. Using concepts from psychology and risk theory, we conducted a longitudinal study pairing data from mail surveys with direct observations of compliance with a wildlife ordinance requiring residents to secure residential garbage from black bears (Ursus americanus). We assessed the relative influence of beliefs and attitudes toward bears and bear proofing, perceived behavioral control, perceived risks and benefits assigned to bears, norms, trust in management, previous experience with conflicts, and demographics on compliance behavior (i.e., bear proofing). Data on previous experience were obtained through direct observation and survey reports. We found that higher compliance rates were associated with more observed conflicts on a respondent's block. Counter to expectations, however, residents were less compliant when they were more trusting of the management agency and perceived more benefits from bears. We suggest that messages have the potential to increase compliance when they empower residents by linking successful management of conflicts to individual actions and emphasize how reducing conflicts could maintain benefits provided by wildlife. Modifying existing educational materials to account for these psychological considerations and evaluating their impact on compliance behavior over time are important next steps in changing human behaviors relevant to the globally important problem of human-wildlife conflict. 相似文献
94.
Nikos Nanos Kajsa Larson Matias Millerón Sara Sjöstedt-de Luna 《Ecological modelling》2010,221(20):2415-678
The estimation of the dispersal kernel for the seedling and sapling stages of the recruitment process was made possible through the application of inverse modeling to dispersal data. This method uses the spatial coordinates of adult trees and the counts of seedlings (or saplings) in small quadrats to estimate the dispersal kernel. The unknown number of recruits produced by an adult tree (the fecundity) is estimated - simultaneously with the dispersal kernel - via an allometric linear model relating the unknown quantity with a (easily) measured characteristic of the adult tree (usually the basal area). However, the allometric relation between tree size and reproductive success in the sapling (or seedling) stage may not be strong enough when numerous, well-documented, post-dispersal processes (such as safe-site limitation for recruitment) cause large post-dispersal seedling mortality, which is usually unrelated to the size of the tree that dispersed them. In this paper we hypothesize that when tree size and reproductive success in the seedling/sapling stage are not well correlated then the use of allometry in inverse modeling is counter-productive and may lead to poor model fits. For these special cases we suggest using a new model for effective dispersal that we term the unrestricted fecundity (UF) model that, contrary to allometric models, makes no assumptions on the fecundities; instead they are allowed to vary freely from one tree to another and even to be zero for trees that are reproductively inactive. Based on this model, we examine the hypothesis that when tree size and reproductive success are weakly correlated and the fecundities are estimated independently of tree size the goodness-of-fit and the ecological meaning of dispersal models (in the seedling or sapling stage) may be enhanced. Parameters of the UF model are estimated through the EM algorithm and their standard errors are approximated via the observed information matrix. We fit the UF model to a dataset from an expanding European beech population of central Spain as well as to a set of simulated dispersal data were the correlation between reproductive success and tree size was moderate. In comparisons with a simple allometric model, the UF model fitted the data better and the parameter estimates were less biased. We suggest using this new approach for modeling dispersal in the seedling and sapling stages when tree size (or other adult-specific covariates) is not deemed to be in strong relation to the reproductive success of adults. Models that use covariates for modeling the fecundity of adults should be preferred when reproductive success and tree size guard a strong relationship. 相似文献
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Chad C. Smith 《Behavioral ecology and sociobiology》2007,61(9):1349-1358
Operational sex ratio (the ratio of sexually active males to fertilizable females) has a major influence on male competition
for mates and male–female interactions. The contributions of male and female density per se to mating system dynamics, however,
are rarely examined, and the fitness consequences are often inferred rather than quantified. Male mosquitofish (Gambusia affinis) compete aggressively and frequently harass females for copulations, a behavior thought to reduce female fitness. Female
fitness can also be reduced by increases in female density, which may affect food availability, cannibalism rates, and chemical
interactions between females. I manipulated male and female densities of G. affinis to measure their effects on male–male aggression, male harassment toward females, and female fitness. I found that males
chased rivals more often and attempted fewer copulations when female density decreased, but surprisingly male density had
no significant effect on the frequency of these male behaviors. In contrast, males’ agonistic displays toward other males
increased with male density, but display behavior was unaffected by female density. These results suggest that male and female
density do not always contribute equally or at all to the patterns of behavior we observe. Female fitness declined as female
density increased, the opposite pattern expected if male harassment is costly to females. This suggests that a strong, negative
effect of female density overwhelmed any potential costs of male harassment. Sources of female density dependence and the
consequences of changes in male and female density to patterns of male behavior are discussed. 相似文献
97.
Can policies designed to maximize exploitation by elites benefit the people who live in forests? Forestry policy throughout the developing world originates from European “scientific” forestry traditions exported during the colonial period. These policies were implemented by foreign and local elite whose interest was to maximize and extract profit. In spite of reforms since the end of the colonial period, policies on the environment usually remain biased against rural communities. Even when more recent policies are fair, the rural poor face severe biases in implementation. In addition, they must compete on an uneven playing field of ethnic and other social inequities and economic hurdles. This article examines how forestry policy and implementation maintain double standards on this uneven playing field in a manner that permanently excludes the rural poor from the natural wealth around them—producing poverty in the process. Change that would support poverty alleviation for forest-based communities requires a radical rethinking of forest policy so as to counterbalance widespread regressive policies and structural asymmetries. 相似文献
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99.
Chad Furl H.O. Sharif Muhammad Alzahrani Almoutaz El Hassan Newfel Mazari 《Journal of the American Water Resources Association》2014,50(1):74-82
This study examines precipitation accumulation and intensity trends across a region in southwest Saudi Arabia characterized by distinct seasonal weather patterns and mountainous terrain. The region is an example of an arid/semiarid area faced with maintaining sustainable water resources with a growing population. Annual and seasonal trends in precipitation amount were examined from 29 rain gages divided among four geographically unique regions from 1945/1946 to 2009. Two of the regions displayed significantly declining annual trends over the time series using a Mann‐Kendall test modified for autocorrelation (α < 0.05). Seasonal analysis revealed insignificant declining trends in at least two of the regions during each season. The largest and most consistent declining trends occurred during wintertime where all regions experienced negative trends. Several intensity metrics were examined in the study area from four additional stations containing daily data from 1985 to 2011. Intensity metrics included total precipitation, wet day count, simple intensity index, maximum daily annual rainfall, and upper/lower precipitation distribution changes. In general, no coherent trends were found among the daily stations suggesting precipitation is intensifying across the study area. The work represents the first of its size in the study area, and one of few in the region due to the lack of available long‐term data needed to properly examine precipitation changes. 相似文献
100.
Tracy J.B. Yager Edward T. Furlong Dana W. Kolpin Chad A. Kinney Steven D. Zaugg Mark R. Burkhardt 《Journal of the American Water Resources Association》2014,50(2):343-357
In 2007, a 1.5‐year field‐scale study was initiated by the U.S. Geological Survey to evaluate the dissipation of contaminants of emerging concern (CECs) following a first agronomic biosolids application to nonirrigated farmland. CECs with the greatest decrease in concentration in the surface biosolids at 180 days post‐application included indole, d‐limonene, p‐cresol, phenol, and skatol. CECs that were present in the largest concentration in 180‐day‐weathered biosolids included stanols, nonylphenols, bisphenol A, bis(2‐ethylhexyl) phthalate, hexahydrohexamethyl cyclopenta‐benzopyran (HHCB), and triclosan. CECs that were detected in pre‐application soil were 3‐beta coprostanol, skatol, acetophenone, beta‐sitosterol, beta‐stigmastanol, cholesterol, indole, p‐cresol, and phenol, most of which are biogenic sterols or fragrances that have natural plant sources in addition to anthropogenic sources, yet their concentrations increased (in some cases, substantially) following biosolids application. Preliminary data indicate the nonylphenols (including NPEO1, NPEO2), OPEO1, benzo[a]pyrene, diethyl phthalate, d‐limonene, HHCB, triclosan, and possibly 3‐beta coprostanol, skatol, beta‐sitosterol, cholesterol, indole, and p‐cresol, migrated downward through the soil by 468 days post‐application, but indicated little uptake by mature wheat plants. This study indicates that some CECs are sufficiently persistent and mobile to be vertically transported into the soil column following biosolids applications to the land surface, even in semiarid regions. 相似文献