Nesting Ecology of West African Dwarf Crocodiles in a Heavily Disturbed Landscape in Chirehin, Ghana
Nesting Ecology of West African Dwarf Crocodiles in a Heavily Disturbed Landscape in Chirehin, Ghana
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加纳奇雷欣严重受干扰景观中西非矮鳄的筑巢生态
DOI：
10.1155/2021/8871631
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发表时间：
2021
期刊：
影响因子：
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通讯作者：
James Perran Ross
中科院分区：
文献类型：
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作者：
Emmanuel Amoah;E. Danquah;James Perran Ross
西非侏儒鳄（Osteolaemus sp. nov. cf. tetraspis）是世界上最受威胁的鳄鱼之一，由于不受管制的狩猎和栖息地丧失相关的人口下降。尽管如此，许多关于其基本生态的问题仍然没有答案，这些数据不足阻碍了有效的侏儒鳄鱼管理。我们描述孵化温度，筑巢成功，孵化率，和西非矮鳄鱼的窝卵数。我们监测了来自2017年和2018年筑巢季节的18个巢穴，这些巢穴位于加纳气候过渡区的Chigalin社区土地上，这是一个高度干扰的农业基质。我们使用流浪汉tidbit®数据记录器来监测蛋室温度以及环境温度对巢穴温度的影响。研究期间记录的每日平均孵育温度为30.7 ℃（±SD = 0.8 ℃，n = 240，范围= 28-33 ℃），与该种属的报告值一致。研究结果表明，矮鳄孵化温度与环境温度之间存在弱的正相关或无相关性，表明巢温几乎不受环境温度的影响。我们发现平均窝卵数为每窝8枚（SD = ±2;范围= 5-13; n = 17），支持以前的报告，该属具有低窝卵数。两个季节的平均筑巢成功率和孵化成功率分别为77.8%和75.3%（SD = ±41.9，n = 18）。三个巢穴被洪水摧毁，一个被一种未知的捕食者摧毁，怀疑是西非尼罗河巨蜥。一般来说，矮鳄选择森林斑块内的高度干扰的景观筑巢，表明需要保护其余的森林斑块。应该努力在这个物种的范围内重复研究，以更好地了解其筑巢生态。
West African dwarf crocodiles (Osteolaemus sp. nov. cf. tetraspis) are among the most threatened crocodilians in the world due to unregulated hunting and habitat loss-related population decline. Despite this, many questions about their basic ecology remain unanswered and this inadequate data hampers effective dwarf crocodile management. We describe incubation temperature, nesting success, hatching rate, and clutch size of West African dwarf crocodiles. We monitored 18 nests from the 2017 and 2018 nesting seasons in the Chirehin Community Land—a highly disturbed agricultural matrix in the climatic transition zone of Ghana. We used Hobo tidbit® data loggers to monitor egg chamber temperature and the effect of ambient temperature on nest temperature. The daily mean incubation temperature recorded during the study was 30.7°C (±SD = 0.8°C, n = 240, range = 28–33°C) and it is congruent with the reported value for the species. The findings from this study suggest a weak positive to no correlation between dwarf crocodile incubation temperature and ambient temperature indicating nest temperature is almost independent of ambient temperature. We found a mean clutch size of 8 eggs per nest (SD = ±2; range = 5–13; n = 17) supporting previous reports that this genus has a low clutch size. The mean nesting success and hatching success across the two seasons were 77.8% and 75.3% (SD = ±41.9, n = 18), respectively. Three nests were destroyed by flood and one by an unknown predator suspected to be a West African Nile monitor lizard. Generally, dwarf crocodiles selected forest patches within the highly disturbed landscape for nesting indicating the need to protect the remaining forest patches. Efforts should be made to repeat the study across this species’ range for an improved understanding of its nesting ecology.