Bergman Eric J, Garrott Robert A, Creel Scott, Borkowski John J, Jaffe Rosemary, Watson E G R
Ecology Department, Montana State University, Bozeman, Montana 59717, USA.
Ecol Appl. 2006 Feb;16(1):273-84. doi: 10.1890/04-1532.
Within predator-prey systems behavior can heavily influence spatial dynamics, and accordingly, the theoretical study of how spatial dynamics relate to stability within these systems has a rich history. However, our understanding of these behaviors in large mammalian systems is poorly developed. To address the relationship between predator selection patterns, prey density, and prey vulnerability, we quantified selection patterns for two fine-scale behaviors of a recovering wolf (Canis lupus) population in Yellowstone National Park, Wyoming, USA. Wolf spatial data were collected between November and May from 1998-1999 until 2001-2002. Over four winters, 244 aerial locations, 522 ground-based telemetry locations, 1287 km of movement data from snow tracking, and the locations of 279 wolf kill sites were recorded. There was evidence that elk (Cervus elaphus) and bison (Bison bison) densities had a weak effect on the sites where wolves traveled and made kills. Wolf movements showed a strong selection for geothermal areas, meadows, and areas near various types of habitat edges. Proximity to edge and habitat class also had a strong influence on the locations where elk were most vulnerable to predation. There was little evidence that wolf kill sites differed from the places where wolves traveled, indicating that elk vulnerability influenced where wolves selected to travel. Our results indicate that elk are more vulnerable to wolves under certain conditions and that wolves are capable of selecting for these conditions. As such, vulnerability plays a central role in predator-prey behavioral games and can potentially impact the systems to which they relate.
在捕食者 - 猎物系统中，行为会严重影响空间动态，因此，关于空间动态如何与这些系统中的稳定性相关的理论研究有着丰富的历史。然而，我们对大型哺乳动物系统中这些行为的理解还很不完善。为了研究捕食者选择模式、猎物密度和猎物脆弱性之间的关系，我们对美国怀俄明州黄石国家公园一个正在恢复的狼群（Canis lupus）的两种精细尺度行为的选择模式进行了量化。狼群的空间数据是在1998 - 1999年至2001 - 2002年的11月至5月期间收集的。在四个冬天里，记录了244个空中位置、522个地面遥测位置、来自雪地追踪的1287公里移动数据以及279个狼捕杀地点的位置。有证据表明，麋鹿（Cervus elaphus）和野牛（Bison bison）的密度对狼的活动地点和捕杀地点的影响较弱。狼的活动对地热区、草地以及各类栖息地边缘附近的区域表现出强烈的选择性。与边缘和栖息地类型的接近程度也对麋鹿最易被捕食的位置有很大影响。几乎没有证据表明狼的捕杀地点与它们的活动地点不同，这表明麋鹿的脆弱性影响了狼选择活动的地点。我们的结果表明，麋鹿在某些条件下更容易受到狼的攻击，而且狼能够选择这些条件。因此，脆弱性在捕食者 - 猎物行为博弈中起着核心作用，并可能对它们所涉及的系统产生潜在影响。
