Hainan Gibbons – the world’s rarest ape species

版权所有杰西卡·布莱恩特（Jessica Bryant）

它的凌晨4点，黑色和我醒来后，我醒来后一周在陡峭的山坡上跋涉，在不宽容的景观上徒步旅行。在中国海南岛上嘲笑国家自然保护区，这是一种荣幸，但这是艰难而艰难的工作。

一个小时的徒步旅行将我和我的森林看守团队带到了一个高架的听力帖子，我们在那里等待着聆听一首难以捉摸的动物的歌。当太阳升起时，我们听到的是，雄性海南长臂猿的呼唤升起了清晨的蝉合唱的球拍上方。这是地球上最稀有的歌曲。

关于the Hainan gibbon

The Hainan gibbon (Nomascus hainanus) is the world’s rarest ape, and probably the rarest mammal, with only one surviving population of just 25 individuals.

Historically, the species was widespread across Hainan, numbering in the thousands, but intensive hunting for Traditional Chinese Medicine and rapid, aggressive forest clearance for industry led to a precipitous decline in the 1950s-1980s.

其余的人口限制为bawanging，而没有圈养的人，对该物种的保护是全球哺乳动物保护的重点。

前往地球上最稀有的歌曲

Getting a fix on the song direction, we tear off towards the gibbons, racing against time, thorny undergrowth and slippery slopes to reach the group before they move on. After some hairy moments, we finally locate the group in a large fig tree.

Conventionally, gibbons are known to live in small, monogamous family groups consisting of one adult male, one adult female, and 1-2 offspring. However, for the Hainan gibbon, we see this polygynous (multi-female to one male) structure.

但是，不仅是一名男性，一名女性和他们的后代构成了这一群体。她的后代还有第二位女性。

This is not the traditional picture of a gibbon social group. Conventionally, gibbons are known to live in small, monogamous family groups consisting of one adult male, one adult female, and 1-2 offspring. However, for the Hainan gibbon, we see this polygynous (multi-female to one male) structure in all of the existing groups. We also see larger overall groups, consisting of six or more members.

通过跟踪群体在整个景观中的范围，很明显，海南长臂猿的家居范围要大得多（估计在1.5-10公里之间²）比大多数长臂猿物种（约0.40 km²).

The drivers behind these apparently anomalous ranging and social habits are not clear, but one explanation is that theymay be a response到当前的外部压力。较大的房屋范围可能是质量有限和/或较差的栖息地的结果，大型，一夫多妻制的群体可能是由于当前人口规模很小而产生的可用伴侣。

This ambiguity makes it difficult to know what the best course of conservation action is for the species. This is a concern because for species that are on the very brink of extinction,time is of the essence- 决定性的行动可能意味着保护成功故事与物种灭绝之间的区别。

关于the research

To clarify things, we conducted a comparative analysis employing data from 39 populations of the 19 currently recognised gibbon species to identify intrinsic versus extrinsic drivers of variation in home range size, social group size, and mating system across the gibbon family.

We found that all three traits showed a strong phylogenetic signal, which means that gibbon species which are more closely related have similar home ranges, group sizes and mating system than expected just by chance.

But, by contextualizing what we see for the Hainan gibbon within the variation in these traits across all gibbons, we were also able to determine that the remnant groups at Bawangling do have larger home ranges than expected (relative to all other gibbon species). It seems that this is likely a result of the critically low population density at this site, rather than issues of habitat quality.

相反，尽管海南长臂猿具有较大的群体大小，但没有观察到的长臂猿大小（对于任何物种 /种群）与我们仅基于它们的系统发育关系所期望的明显不同。

Furthermore, there is no evidence that the polygynous mating system observed for the Hainan gibbon is driven by any existing external factors. This suggests that large, polygynous groups may be the norm for this species.

这对保护意味着什么？

通过取笑海南长臂猿的自然生态和行为特征，我们揭示了保护计划的重要考虑因素。

任何潜在的保护活动都必须将物种的复杂，一夫多妻制结构视为其生物学的内在组成部分。

首先，很明显，仅旨在改善栖息地质量的行动就不太可能解决当前对海南长臂猿人口恢复的限制，因此可能需要更密集的管理。

Second, any potential conservation activities must consider the complex, polygynous social structure of the species as an intrinsic component of its biology.

我们目前正在与Bawangling管理人员合作，以确保将这些发现纳入海南长臂猿的保护管理中，以期保留和恢复最后一个幸存的人口，并最终可以建立其他人口。

Perhaps, with careful but proactive conservation action based upon this sort of sound scientific evidence, in the near future the Hainan gibbon’s song can echo through the valleys of many Hainanese mountains once again.