干旱区生态环境知识资源中心(Arid): Reproductive investments of a small, arid zone tortoise Chersobius signatus: Follicle and egg development

Arid

DOI	10.1111/azo.12269
	Reproductive investments of a small, arid zone tortoise Chersobius signatus: Follicle and egg development
	Hofmeyr, Margaretha D.; Henen, Brian T.; Loehr, Victor J. T.
通讯作者	Hofmeyr, MD (corresponding author), Univ Western Cape, Dept Biodivers & Conservat Biol, ZA-7535 Bellville, South Africa.
来源期刊	ACTA ZOOLOGICA
ISSN	0001-7272
EISSN	1463-6395
出版年	2020
卷号	101 期号:1 页码:39-50
英文摘要	We used ultrasonography and radiography to evaluate whether body size (BS), body condition (BC) and environmental factors influenced reproductive investments by Chersobius signatus in September 2000 and from September 2003 to November 2004. Follicle volume increased with increasing BS, BC and rainfall but decreased with increasing temperature. Egg volume averaged 8.8% of body volume, increased allometrically with BS, but was not affected by BC, rainfall or temperature and did not differ between first and second clutches. Most females produced at least one single-egg clutch per year, even when BC was low. Many females produced two, possibly more, clutches but some forfeited reproduction in some years. Females often retained large follicles from one season to the next with 18%-71% carrying pre-ovulatory sized follicles in different times of the year. Increasing temperatures likely influenced timing of first ovulations in August while decreasing water and food availability, linked with high temperatures, possibly terminated ovulations by November. The gravid season was short compared to other winter-rainfall tortoises in South Africa. We propose that the females' small bodies may constrain investments in eggs, resulting in low fecundity, which is countered by producing large hatchlings with high survivorship in an arid habitat.
英文关键词	Homopus radiography reptile South Africa ultrasonography Winter-rainfall X-ray
类型	Article
语种	英语
收录类别	SCI-E
WOS记录号	WOS:000607415000004
WOS类目	Anatomy & Morphology ; Zoology
WOS研究方向	Anatomy & Morphology ; Zoology
资源类型	期刊论文
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/348684
作者单位	[Hofmeyr, Margaretha D.; Henen, Brian T.; Loehr, Victor J. T.] Univ Western Cape, Dept Biodivers & Conservat Biol, Chelonian Biodivers & Conservat, Bellville, South Africa; [Henen, Brian T.] MCAGCC, Marine Air Ground Task Force Training Command, Environm Affairs, Twentynine Palms, CA USA; [Loehr, Victor J. T.] Homopus Res Fdn, Ijsselstein, Netherlands
推荐引用方式 GB/T 7714	Hofmeyr, Margaretha D.,Henen, Brian T.,Loehr, Victor J. T.. Reproductive investments of a small, arid zone tortoise Chersobius signatus: Follicle and egg development[J],2020,101(1):39-50.
APA	Hofmeyr, Margaretha D.,Henen, Brian T.,&Loehr, Victor J. T..(2020).Reproductive investments of a small, arid zone tortoise Chersobius signatus: Follicle and egg development.ACTA ZOOLOGICA,101(1),39-50.
MLA	Hofmeyr, Margaretha D.,et al."Reproductive investments of a small, arid zone tortoise Chersobius signatus: Follicle and egg development".ACTA ZOOLOGICA 101.1(2020):39-50.