Department of Fish, Wildlife and Conservation Biology, Colorado State University, Fort Collins, CO 80523, USA.
Conserv Biol. 2011 Oct;25(5):1002-9. doi: 10.1111/j.1523-1739.2011.01713.x. Epub 2011 Jul 25.
Declines in economic activity and associated changes in human livelihood strategies can increase threats of species overexploitation. This is exemplified by the effects of economic crises, which often drive intensification of subsistence poaching and greater reliance on natural resources. Whereas development theory links natural resource use to social-economic conditions, few empirical studies of the effect of economic downturns on wild animal species have been conducted. I assessed the relations between African elephant (Loxodonta africana) mortality and human-caused wounds in Samburu, Kenya and (1) livestock and maize prices (measures of local economic conditions), (2) change in national and regional gross domestic product (GDP) (measures of macroeconomic conditions), and (3) the normalized difference vegetation index (NDVI) (a correlate of primary productivity). In addition, I analyzed household survey data to determine the attitudes of local people toward protected areas and wild animals in the area. When cattle prices in the pastoralist study region were low, human-caused wounds to and adult mortality of elephants increased. The NDVI was negatively correlated with juvenile mortality, but not correlated with adult mortality. Changes in Kenyan and East Asian (primary market for ivory) GDP did not explain significant variation in mortality. Increased human wounding of elephants and elephant mortality during periods of low livestock prices (local economic downturns) likely reflect an economically driven increase in ivory poaching. Local but not macroeconomic indices explained significant variation in mortality, likely due to the dominance of the subsistence economy in the study area and its political and economic isolation. My results suggest economic metrics can serve as effective indicators of changes in human use of and resulting effects on natural resources. Such information can help focus management approaches (e.g., antipoaching effort or proffering of alternative occupational opportunities) that address variation in local activities that threaten plant and animal populations.
经济活动的减少以及人类生计策略的相应变化可能会增加物种过度开发的威胁。经济危机就是一个很好的例子，它通常会导致生存性偷猎的加剧以及对自然资源的更大依赖。虽然发展理论将自然资源的利用与社会经济条件联系起来，但很少有关于经济衰退对野生动物物种影响的实证研究。我评估了肯尼亚桑布鲁的非洲象（Loxodonta africana）死亡率与人为造成的伤口之间的关系，并研究了（1）牲畜和玉米价格（当地经济状况的衡量标准），（2）国家和地区国内生产总值（GDP）的变化（宏观经济状况的衡量标准），以及（3）归一化差异植被指数（NDVI）（初级生产力的相关指标）。此外，我分析了家庭调查数据，以确定当地居民对该地区保护区和野生动物的态度。当牧民研究区的牛价较低时，人为造成的大象伤口和成年大象的死亡率增加。NDVI 与幼象死亡率呈负相关，但与成年大象死亡率无关。肯尼亚和东亚（象牙的主要市场）GDP 的变化并不能解释死亡率的显著变化。在牲畜价格较低（当地经济衰退）期间，大象受到的人为伤害和大象的死亡率增加，可能反映了出于经济目的的象牙偷猎活动的增加。当地而非宏观经济指标解释了死亡率的显著变化，这可能是由于研究区以自给经济为主，以及其政治和经济孤立。我的研究结果表明，经济指标可以作为人类利用自然资源和由此对其产生影响变化的有效指标。这些信息可以帮助确定管理方法（例如，反偷猎工作或提供替代职业机会），以解决威胁动植物种群的当地活动的变化。
