Department of Forestry and Natural Resources, Purdue University, West Lafayette, Indiana, United States of America.
PLoS One. 2012;7(7):e40473. doi: 10.1371/journal.pone.0040473. Epub 2012 Jul 6.
Timber harvesting has been shown to have both positive and negative effects on forest dwelling species. We examined the immediate effects of timber harvests (clearcuts and group selection openings) on ectotherm behavior, using the eastern box turtle as a model. We monitored the movement and thermal ecology of 50 adult box turtles using radiotelemetry from May-October for two years prior to, and two years following scheduled timber harvests in the Central Hardwoods Region of the U.S. Annual home ranges (7.45 ha, 100% MCP) did not differ in any year or in response to timber harvests, but were 33% larger than previous estimates (range 0.47-187.67 ha). Distance of daily movements decreased post-harvest (from 22 m±1.2 m to 15 m±0.9 m) whereas thermal optima increased (from 23±1°C to 25±1°C). Microclimatic conditions varied by habitat type, but monthly average temperatures were warmer in harvested areas by as much as 13°C. Animals that used harvest openings were exposed to extreme monthly average temperatures (∼40°C). As a result, the animals made shorter and more frequent movements in and out of the harvest areas while maintaining 9% higher body temperatures. This experimental design coupled with radiotelemetry and behavioral observation of a wild ectotherm population prior to and in response to anthropogenic habitat alteration is the first of its kind. Our results indicate that even in a relatively contiguous forested landscape with small-scale timber harvests, there are local effects on the thermal ecology of ectotherms. Ultimately, the results of this research can benefit the conservation and management of temperature-dependent species by informing effects of timber management across landscapes amid changing climates.
采伐木材对森林栖息物种既有正面影响，也有负面影响。我们以东部箱龟（eastern box turtle）为模型，研究了木材采伐（皆伐和块状皆伐）对变温动物行为的直接影响。在 scheduled timber harvests 之前的两年和之后的两年，我们使用无线电遥测技术监测了 50 只成年箱龟的运动和热生态学。每年的家域（7.45 公顷，100% MCP）在任何一年或对木材采伐都没有差异，但比以前的估计大 33%（范围为 0.47-187.67 公顷）。每日活动距离在采伐后减少（从 22 米±1.2 米减少到 15 米±0.9 米），而热最佳值增加（从 23±1°C 增加到 25±1°C）。微气候条件因栖息地类型而异，但收获区的月平均温度要高 13°C。使用收获开口的动物暴露在极端的月平均温度（约 40°C）下。结果，动物在收获区内外进行了更短、更频繁的移动，同时保持了 9%更高的体温。这种实验设计加上对野生动物种群在人为改变栖息地前后的无线电遥测和行为观察，是首例。我们的研究结果表明，即使在相对连续的森林景观中进行小规模的木材采伐，也会对变温动物的热生态学产生局部影响。最终，这项研究的结果可以通过了解气候变化中景观层面上的木材管理对温度依赖物种的影响，为这些物种的保护和管理提供信息。
