Bioko: critically important nesting habitat for sea turtles of West Africa
Bioko: critically important nesting habitat for sea turtles of West Africa
复制标题
比奥科：西非海龟极其重要的筑巢栖息地
DOI：
--
复制
发表时间：
2010
影响因子：
3.4
通讯作者：
J. Raga
中科院分区：
文献类型：
--
作者：
J. Tomás;B. Godley;J. Castroviejo;J. Raga
我们评估了赤道几内亚(中部非洲)比奥科岛海龟筑巢种群的保护状况和面临的威胁。对海滩进行了监测，以获得详细的海龟巢统计数据，并在可能的情况下对成年雌性海龟进行了标记。在该地区发现了四种筑巢的海龟：绿海龟(Cheronia Mydas)、棱皮龟(Dermochelys Coriacea)、橄榄(Lappochelys Olivacea)和鹰嘴龟(Eretmochelys Imbricata)；前两种海龟的筑巢数量具有区域重要性。筑巢活动集中在11月至2月，高峰期在12月至1月。连续两个季节的标记和重新捕获的绿海龟表明，估计在该地区筑巢的雌性海龟分别为560只(四分位数范围：420-1,681)和414只(四分位数范围：190-1,255)。据估计，第一季和第二季棱皮鸟的筑巢数量分别为123至215只和243至293只。其他两种数量较少(橄榄：19-29和28-43只；鹰嘴龟：4-10只和2只)。数据与该地区最近的调查进行了比较，并与与人类有关的威胁信息进行了背景分析。尽管筑巢种群的规模很大，但在筑巢地点持续允许和非法捕获成年海龟对这些繁殖群体构成了严重威胁。此外，整个几内亚湾的TAG返回表明，区域渔业的捕捞水平也可能是一个主要威胁。
We evaluate the conservation status and threats faced by sea turtle nesting populations at Bioko Island, Equatorial Guinea (Central Africa). Beaches were monitored to obtain a detailed sea turtle nest census and, where possible, tagging of adult females was undertaken. Four sea turtle species were found nesting in the area: the green turtle (Chelonia mydas), the leatherback (Dermochelys coriacea), the olive ridley (Lepidochelys olivacea) and the hawksbill (Eretmochelys imbricata); with the former two species nesting in regionally important numbers. Nesting activity was concentrated between November and February, with a peak in December–January. Tagging and recapture of green turtles in two consecutive seasons suggested an estimated 560 (interquartile range: 420–1,681) and 414 (interquartile range: 190–1,255) nesting females in the area, respectively. Estimated numbers of nesting leatherbacks ranged from 123 to 215 and 243 to 293 in the first and second season, respectively. The other two species were less abundant (olive ridley: 19–29 and 28–43; hawksbill: 4–10 and 2 turtles). Data were compared with more recent surveys in the area and contextualised with information on human related threats. Despite the size of nesting stocks, ongoing permitted and illegal take of adult turtles at the nesting site constitutes a serious threat for these breeding aggregations. Additionally, tag returns from throughout the Gulf of Guinea suggest that the level of take in regional fisheries may also be a major threat.