Why is the Northern Idaho Ground Squirrel Rare?

IF 0.5 4区 环境科学与生态学 Q4 ECOLOGY
E. Yensen, Elizabeth J. Dyni
{"title":"Why is the Northern Idaho Ground Squirrel Rare?","authors":"E. Yensen, Elizabeth J. Dyni","doi":"10.3955/046.094.0101","DOIUrl":null,"url":null,"abstract":"Abstract Urocitellus brunneus (northern Idaho ground squirrel) has a geographic range of approximately 1,600 km2 in west-central Idaho. It was listed as Threatened under the US Endangered Species Act in 2000. To assist recovery efforts, we tested three hypotheses that might explain its rarity: 1) specialization on a now uncommon habitat; 2) competition with a larger congener, U. columbianus (Columbian ground squirrel); and 3) anthropogenic impacts. We explored the habitat specialization hypothesis by comparing attributes of sites occupied exclusively by each species with areas occupied alternately by each. Sites occupied by U. brunneus had significantly more bare ground; shallower, rockier, harder soils; higher soil temperatures during the active season; less plant cover; shorter vegetation; lower net annual aboveground productivity; and fewer shrubs than sites occupied by U. columbianus. Discriminant analysis showed U. brunneus could occupy some areas used by U. columbianus, but U. columbianus seldom occupied areas occupied by U. brunneus. U. brunneus also occurred in earlier successional communities and could occupy mesic meadows with high water tables not utilized by U. columbianus. In field observations and arena trials, U. brunneus avoided U. columbianus. In two removal experiments U. brunneus expanded into areas from which U. columbianus had been removed, but vacated when U. columbianus returned. Anthropogenic impacts included habitat conversion, conifer invasion of meadows resulting from timber management and fire suppression practices, systematic poisoning, target shooting, and invasive species; grazing appears to have mixed impacts. U. brunneus is rare due to a combination of habitat specialization, competition, and anthropogenic impacts.","PeriodicalId":49743,"journal":{"name":"Northwest Science","volume":"94 1","pages":"1 - 23"},"PeriodicalIF":0.5000,"publicationDate":"2020-04-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"4","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Northwest Science","FirstCategoryId":"93","ListUrlMain":"https://doi.org/10.3955/046.094.0101","RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"ECOLOGY","Score":null,"Total":0}
引用次数: 4

Abstract

Abstract Urocitellus brunneus (northern Idaho ground squirrel) has a geographic range of approximately 1,600 km2 in west-central Idaho. It was listed as Threatened under the US Endangered Species Act in 2000. To assist recovery efforts, we tested three hypotheses that might explain its rarity: 1) specialization on a now uncommon habitat; 2) competition with a larger congener, U. columbianus (Columbian ground squirrel); and 3) anthropogenic impacts. We explored the habitat specialization hypothesis by comparing attributes of sites occupied exclusively by each species with areas occupied alternately by each. Sites occupied by U. brunneus had significantly more bare ground; shallower, rockier, harder soils; higher soil temperatures during the active season; less plant cover; shorter vegetation; lower net annual aboveground productivity; and fewer shrubs than sites occupied by U. columbianus. Discriminant analysis showed U. brunneus could occupy some areas used by U. columbianus, but U. columbianus seldom occupied areas occupied by U. brunneus. U. brunneus also occurred in earlier successional communities and could occupy mesic meadows with high water tables not utilized by U. columbianus. In field observations and arena trials, U. brunneus avoided U. columbianus. In two removal experiments U. brunneus expanded into areas from which U. columbianus had been removed, but vacated when U. columbianus returned. Anthropogenic impacts included habitat conversion, conifer invasion of meadows resulting from timber management and fire suppression practices, systematic poisoning, target shooting, and invasive species; grazing appears to have mixed impacts. U. brunneus is rare due to a combination of habitat specialization, competition, and anthropogenic impacts.
为什么北爱达荷地松鼠罕见?
摘要Urochitellus bruneus(爱达荷州北部地松鼠)在爱达荷州中西部的地理范围约为1600平方公里。2000年,根据美国《濒危物种法》,它被列为濒危物种。为了帮助恢复工作,我们测试了三个可能解释其罕见性的假设:1)在一个现在不常见的栖息地专门化;2) 与更大的同类哥伦比亚松鼠竞争;以及3)人为影响。我们通过比较每个物种单独占据的地点和每个物种交替占据的区域的属性,探索了栖息地专门化假说。布伦纽斯大学占用的场地裸露得多;较浅、岩石较多、较硬的土壤;活跃季节土壤温度较高;植物覆盖较少;植被较短;年地上净生产力较低;灌木比哥伦比亚大学占据的场地少。判别分析表明,布鲁纽虫可以占据一些哥伦比亚纽虫使用的区域,但哥伦比亚纽虫很少占据布鲁纽鱼使用的区域。布伦纽虫也出现在早期的演替群落中,可以占据哥伦比亚纽虫没有利用的地下水位高的mesic草地。在野外观察和竞技场试验中,布鲁纽斯大学避开了哥伦比亚大学。在两次移除实验中,布鲁纽斯猪笼草扩展到了已经移除哥伦比亚猪笼草的区域,但当哥伦比亚猪笼菜回来时,它们就腾空了。人为影响包括栖息地转换、木材管理和灭火措施导致的针叶树对草地的入侵、系统中毒、打靶和入侵物种;放牧的影响似乎喜忧参半。由于栖息地的特殊性、竞争性和人为影响,布鲁纽斯是罕见的。
本文章由计算机程序翻译,如有差异,请以英文原文为准。
求助全文
约1分钟内获得全文 求助全文
来源期刊
Northwest Science
Northwest Science 环境科学-生态学
CiteScore
1.30
自引率
0.00%
发文量
23
审稿时长
>36 weeks
期刊介绍: The pages of Northwest Science are open to original and fundamental research in the basic, applied, and social sciences. All submissions are refereed by at least two qualified peer reviewers. Papers are welcome from authors outside of the Pacific Northwest if the topic is suitable to our regional audience.
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
确定
请完成安全验证×
copy
已复制链接
快去分享给好友吧!
我知道了
右上角分享
点击右上角分享
0
联系我们:info@booksci.cn Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术官方微信