干旱区生态环境知识资源中心(Arid): Structure and projected decline of a Karoo dwarf tortoise population

Arid

DOI	10.1002/jwmg.22159
	Structure and projected decline of a Karoo dwarf tortoise population
	Loehr, Victor J. T.; Keswick, Toby
通讯作者	Loehr, VJT
来源期刊	JOURNAL OF WILDLIFE MANAGEMENT
ISSN	0022-541X
EISSN	1937-2817
出版年	2022
卷号	86 期号:2
英文摘要	Inconspicuous, secretive, or sparsely distributed species receive relatively little research attention, potentially leading to uncertainty about their status and lack of efforts to conserve them. Karoo dwarf tortoises (Chersobius boulengeri) are endemic to South Africa, spend most of the time in retreats at remote arid locations, and are seldom seen. We conducted a 3-year (2018-2020) mark-recapture study to investigate the size and structure of the only Karoo dwarf tortoise population currently known to exist. The population in the 16-ha core of our study site consisted primarily of adult males and females, at a density of 3.3 individuals/ha. Many individuals had severely worn shells and appeared old. Small individuals (straight carapace length <65 mm) represented just 8% of the population and were mostly recent hatchlings. Overall, tortoises had high estimated survival rates (0.77-0.95; lower 95% confidence limit for the smallest tortoises was 0.16), despite a 15-month drought. The lack of small individuals may reflect low levels of recruitment and population decline. Predation by corvids was an obvious threat to all size classes. We estimated that the local population across the 250-ha study area was 800-900 males and females, and recommend precautionary conservation measures focused on reducing human-subsidized avian predation.
英文关键词	Chersobius boulengeri citizen science corvids demography mortality population dynamics predation recruitment
类型	Article
语种	英语
开放获取类型	hybrid
收录类别	SCI-E
WOS记录号	WOS:000739925200001
WOS关键词	HOMOPUS-SIGNATUS-SIGNATUS ; ARID-ZONE TORTOISE ; GOPHERUS-AGASSIZII ; ACTIVITY PATTERNS ; MODEL SELECTION ; CONSERVATION ; SURVIVAL ; DENSITY ; DESERT ; PREDATION
WOS类目	Ecology ; Zoology
WOS研究方向	Environmental Sciences & Ecology ; Zoology
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/376598
推荐引用方式 GB/T 7714	Loehr, Victor J. T.,Keswick, Toby. Structure and projected decline of a Karoo dwarf tortoise population[J],2022,86(2).
APA	Loehr, Victor J. T.,&Keswick, Toby.(2022).Structure and projected decline of a Karoo dwarf tortoise population.JOURNAL OF WILDLIFE MANAGEMENT,86(2).
MLA	Loehr, Victor J. T.,et al."Structure and projected decline of a Karoo dwarf tortoise population".JOURNAL OF WILDLIFE MANAGEMENT 86.2(2022).