Demographic and phenotypic effects of human mediated trophic subsidy on a large Australian lizard (Varanus varius): meal ticket or last supper?
Demographic and phenotypic effects of human mediated trophic subsidy on a large Australian lizard (Varanus varius): meal ticket or last supper?
复制标题
DOI：
10.1371/journal.pone.0034069
复制
发表时间：
2012
期刊：
影响因子：
3.7
通讯作者：
Dempster T
中科院分区：
文献类型：
--
作者：
Jessop TS;Smissen P;Scheelings F;Dempster T
人类越来越多地通过改变营养循环和生产力来补贴和改变自然食物网。在人类营养补贴集中并持续存在于自然环境的地方，它们的消费可能会通过改变影响种群动态的栖息地偏好、表型和适应属性而对野生动物产生复杂的后果。人类营养补贴在概念上为获得更多热量和改变营养投入的动物创造了成本和收益。在这里，我们评估了一种常见的陆地人类营养补贴-人类食物垃圾-对澳大利亚南部一种大型捕食性蜥蜴(∼2 m长)的种群和表型参数(包括形态和生理健康指标)的影响，并与未接受人类营养补贴的个体进行了比较。在人类营养补贴地点，与天然林中的对照地点相比，蜥蜴的数量显著增加，性别比例高度男性偏向。接受人类营养补贴的蜥蜴明显更长、更重，身体状况也更好。血液寄生虫在人类营养补贴蜥蜴中明显较低。总而言之，我们的结果表明，人类营养补贴部位对成年男性蕾丝监测器特别有吸引力，并具有很大的表型效应。然而，我们不能排除在人类营养补贴地点聚集男性偏向的大型监视器，可能会通过配偶竞争和后代存活，以及通过更多地暴露于卵和幼体被捕食而导致生殖适合度降低。这些可能性可能会对人口产生负面影响。这些大型捕食者的聚集也可能通过提高捕食水平对周围的食物网动态产生流动影响。鉴于能量和营养物质流入食物网是调节种群及其群落的核心，我们主张对人类营养补贴进行进一步研究，以评估这一重大人类环境变化可能带来的巨大生态影响。
Humans are increasingly subsidizing and altering natural food webs via changes to nutrient cycling and productivity. Where human trophic subsidies are concentrated and persistent within natural environments, their consumption could have complex consequences for wild animals through altering habitat preferences, phenotypes and fitness attributes that influence population dynamics. Human trophic subsidies conceptually create both costs and benefits for animals that receive increased calorific and altered nutritional inputs. Here, we evaluated the effects of a common terrestrial human trophic subsidies, human food refuse, on population and phenotypic (comprising morphological and physiological health indices) parameters of a large predatory lizard (∼2 m length), the lace monitor (Varanus varius), in southern Australia by comparison with individuals not receiving human trophic subsidies. At human trophic subsidies sites, lizards were significantly more abundant and their sex ratio highly male biased compared to control sites in natural forest. Human trophic subsidies recipient lizards were significantly longer, heavier and in much greater body condition. Blood parasites were significantly lower in human trophic subsidies lizards. Collectively, our results imply that human trophic subsidized sites were especially attractive to adult male lace monitors and had large phenotypic effects. However, we cannot rule out that the male-biased aggregations of large monitors at human trophic subsidized sites could lead to reductions in reproductive fitness, through mate competition and offspring survival, and through greater exposure of eggs and juveniles to predation. These possibilities could have negative population consequences. Aggregations of these large predators may also have flow on effects to surrounding food web dynamics through elevated predation levels. Given that flux of energy and nutrients into food webs is central to the regulation of populations and their communities, we advocate further studies of human trophic subsidies be undertaken to evaluate the potentially large ecological implications of this significant human environmental alteration.
登录
查看更多内容
影响因子：
4.8
作者：
ARCESE, P;SMITH, JNM
通讯作者：
SMITH, JNM
影响因子：
5.9
作者：
Fedriani, JM;Fuller, TK;Sauvajot, RM
通讯作者：
Sauvajot, RM
影响因子：
5.2
作者：
Cotter, Sheena C.;Simpson, Stephen J.;Wilson, Kenneth
通讯作者：
Wilson, Kenneth
影响因子：
2.3
作者：
Meretsky, VJ;Mannan, RW
通讯作者：
Mannan, RW
影响因子：
1.7
作者：
Oro, D;Genovart, X;GarciaGans, J
通讯作者：
GarciaGans, J