Doctorado en Ciencias Biológicas y de la Salud, Universidad Autónoma Metropolitana, Ciudad de México, Mexico.
Departamento El Hombre y su Ambiente, División de Ciencias Biológicas y de la Salud, Universidad Autónoma Metropolita-Unidad Xochimilco, Coyoacán, Mexico City, Mexico.
PLoS One. 2021 Dec 1;16(12):e0260325. doi: 10.1371/journal.pone.0260325. eCollection 2021.
Resource partitioning, and especially dietary partitioning, is a mechanism that has been studied for several canid species as a means to understand competitive relationships and the ability of these species to coexist. Coyotes (Canis latrans) and gray foxes (Urocyon cinereoargenteus) are two canid species that are widely distributed, in Mexico, and they are sympatric throughout most of their distribution range. However, trophic dynamic and overlap between them have not been thoroughly studied. In order to better understand their ecological relationship and potential competitive interactions, we studied the trophic niche overlap between both canids in a temperate forest of Durango, Mexico. The results are based on the analysis of 540 coyote and 307 gray fox feces collected in 2018. Both species consumed a similar range of food items, but the coyote consumed large species while the gray fox did not. For both species, the most frequently consumed food categories throughout the year and seasonally were fruit and wild mammals (mainly rodents and lagomorphs). Coyotes had higher trophic diversity in their annual diet (H' = 2.33) than gray foxes (H' = 1.80). When analyzing diets by season, trophic diversity of both species was higher in winter and spring and tended to decrease in summer and autumn. When comparing between species, this parameter differed significantly during all seasons except for summer. Trophic overlap throughout the year was high (R0 = 0.934), with seasonal variation between R0 = 0.821 (autumn) and R0 = 0.945 (spring). Both species based their diet on the most available food items throughout each season of the year, having high dietary overlap which likely can lead to intense exploitative competition processes. However, differences in trophic diversity caused by differential prey use can mitigate competitive interactions, allowing these different sized canid species to coexist in the study area.
资源分区，特别是饮食分区，是一种已被研究用于几种犬科物种的机制，以了解它们的竞争关系和共存能力。郊狼（Canis latrans）和灰狐（Urocyon cinereoargenteus）是两种分布广泛的犬科动物，在墨西哥，它们在大部分分布范围内是同域分布的。然而，它们之间的营养动态和重叠并没有被彻底研究过。为了更好地了解它们的生态关系和潜在的竞争相互作用，我们研究了两种犬科动物在墨西哥杜兰戈州一个温带森林中的营养生态位重叠。研究结果基于对 2018 年收集的 540 只郊狼和 307 只灰狐粪便的分析。两种物种都食用了相似范围的食物，但郊狼吃大型物种，而灰狐不吃。对于这两种物种，全年和季节性最常食用的食物类别都是水果和野生动物（主要是啮齿动物和兔形目动物）。郊狼的年度饮食中营养多样性较高（H' = 2.33），而灰狐的饮食多样性较低（H' = 1.80）。当按季节分析饮食时，两种物种在冬季和春季的营养多样性较高，而在夏季和秋季则呈下降趋势。在物种间比较时，除了夏季，该参数在所有季节都有显著差异。全年的营养重叠率较高（R0 = 0.934），季节性变化范围为 R0 = 0.821（秋季）至 R0 = 0.945（春季）。两种物种的饮食都基于每年每个季节最易获得的食物，具有很高的饮食重叠率，这可能导致激烈的掠夺性竞争过程。然而，由于捕食者利用的不同，营养多样性的差异可以减轻竞争相互作用，使这些不同大小的犬科物种能够在研究区域共存。
