雄性獵豹在“貓吧”留言。 了解這些地方有助于拯救物種
當(dāng)農(nóng)民將牛群從獵豹通訊中心移走時(shí)，他們失去的小牛減少了

???? 2020 年 12 月 7 日 作者：Virginia Morell

新的研究表明，非洲的特定樹木和大石頭就像雄性獵豹的酒吧。大型貓科動物利用這些地方尋找配偶并向其他雄性發(fā)送信號，有效地使它們成為其物種的交流中心。研究表明，它們也可能是從憤怒的農(nóng)民手中拯救動物的關(guān)鍵。

“向他們致敬！”布里斯托大學(xué)的行為生態(tài)學(xué)家蒂姆·卡羅 (Tim Caro) 談到了研究人員的工作。他指出，這項(xiàng)研究表明，在做出保護(hù)管理決策之前了解野生動物的行為非常重要。

Caro 的早期研究是獵豹研究的起點(diǎn)。在 1980 年代，他發(fā)現(xiàn)大型貓科動物在哺乳動物中擁有獨(dú)特的社會系統(tǒng)：獨(dú)居的雌性貓科動物分布在巨大的區(qū)域內(nèi)，包括雄性貓科動物擁有的較小領(lǐng)土。雄性之間爭奪領(lǐng)地的競爭非常激烈，它們經(jīng)常與一兩個(gè)不相關(guān)的雄性結(jié)成聯(lián)盟來保衛(wèi)自己的土地。沒有領(lǐng)地的雄性（稱為漂浮物）四處游蕩，希望接管這些財(cái)產(chǎn)之一。

卡羅還指出，雄性貓有不同的位置，通常是樹或大石頭，它們經(jīng)常用氣味標(biāo)記。在這項(xiàng)新研究中，由萊布尼茨動物園和野生動物研究所空間生態(tài)學(xué)家 Joerg Melzheimer 領(lǐng)導(dǎo)的科學(xué)家們意識到，這些地方正在發(fā)生一些重要的事情。

2007 年至 2018 年期間，Melzheimer 及其同事為生活在納米比亞中部近 11,000 平方公里牧場的 106 只成年獵豹安裝了無線電項(xiàng)圈。研究小組發(fā)現(xiàn)，領(lǐng)地雄性有一半的時(shí)間在這些樹木或巖石上，經(jīng)常用尿液標(biāo)記它們。與此同時(shí)，漂浮物定期訪問這些網(wǎng)站，但只是停下來聞一聞。雌性偶爾也會檢查，在發(fā)情時(shí)留下痕跡。梅爾茨海默說，每個(gè)這樣的地點(diǎn)通常都位于雄性領(lǐng)地的中心，其功能“就像一個(gè)受歡迎的酒吧，在那里你可能有更好的機(jī)會找到交配對象”。

隨著時(shí)間的推移，這些中心是穩(wěn)定的。即使當(dāng)新的雄性接管一個(gè)領(lǐng)地時(shí)，它們也會使用與前任主人相同的氣味標(biāo)記位置。
獵豹連續(xù)領(lǐng)土持有者的數(shù)字地圖，帶有指示通信樞紐的圖標(biāo)

一只獵豹通訊樞紐的地圖。在 A 中，從黑色到黃色到藍(lán)色到紅色的連續(xù)彩色圓點(diǎn)可以看出，男性領(lǐng)地持有者隨著時(shí)間的推移發(fā)生了變化。在 B 中，綠色星星代表通信樞紐周圍的獵豹標(biāo)記位置。Melzheimer 等人。

從保護(hù)的角度來看，這可能很重要。和大多數(shù)大型貓科動物一樣，獵豹也面臨著危險(xiǎn)的未來。棲息地喪失、獵物減少以及與人的沖突使它們的數(shù)量從 1975 年的 14,000 只減少到今天的約 7000 只。大多數(shù)現(xiàn)在在東部和南部非洲保護(hù)區(qū)以外的農(nóng)田上發(fā)現(xiàn)；亞洲獵豹幾乎滅絕。

雖然獵豹不是牲畜的主要?dú)⑹?，但它們會獵殺幼崽，特別是當(dāng)它們找不到自己的野生獵物——羚羊、瞪羚、黑斑羚和疣豬時(shí)。在納米比亞和其他地方，農(nóng)民會先發(fā)制人地殺死獵豹，或者為了報(bào)復(fù)攻擊他們的牲畜或獵物。這種與農(nóng)場有關(guān)的殺戮被認(rèn)為是對獵豹的主要威脅。

Melzheimer 的團(tuán)隊(duì)與 35 名因獵豹而失去牲畜的農(nóng)民合作。其中，有六個(gè)在他們的土地上有一個(gè)獵豹通信中心，并且有充分記錄的獵豹攻擊。 Melzheimer 認(rèn)為獵豹在這些地點(diǎn)收集的信息非常重要，如果農(nóng)民將動物轉(zhuǎn)移到其他地方，貓就不會跟隨牲畜。盡管六位農(nóng)民持懷疑態(tài)度，但他們同意將帶乳牛的牛群轉(zhuǎn)移到遠(yuǎn)離這些中心的地區(qū)。研究小組今天在《美國國家科學(xué)院院刊》上報(bào)告說，隨后被獵豹捕食的小牛數(shù)量平均減少了 86%。

伊利諾伊大學(xué)厄巴納-香檳分校的食肉動物生態(tài)學(xué)家馬克西米利安艾倫說，這是一個(gè)“驚人的”下降，他沒有參與這項(xiàng)研究。 “似乎這些發(fā)現(xiàn)可以應(yīng)用于獵豹與農(nóng)業(yè)和畜牧業(yè)重疊的任何領(lǐng)域?！?br>
梅爾茨海默同意。 “我們發(fā)現(xiàn)不存在‘問題動物’，”他說，而是“‘問題區(qū)域’?！彼a(bǔ)充說，“[在納米比亞這一地區(qū)]擁有通信中心的每個(gè)農(nóng)民現(xiàn)在都在實(shí)施我們的建議， "而且該國還有更多的農(nóng)民正在參與這項(xiàng)研究。

其他貓有不同的社會結(jié)構(gòu)和中心，所以這項(xiàng)研究不會直接幫助它們。但這項(xiàng)工作確實(shí)提出了一種思考人類與野生動物沖突的新方法——這是“絕對值得探索的東西”，艾倫說。

*更正，12 月 8 日，上午 10:15：本文已更改，以反映所有貓科動物，無論是野生的還是家養(yǎng)的，都會標(biāo)記其領(lǐng)土；不過，它們的做法與獵豹不同。

Farmers lost fewer calves when they moved herds away from cheetah communication hubs

Specific trees and large rocks in Africa are like bars for male cheetahs, new research reveals. The big cats use these places to find mates and send signals to other males, effectively making them communication hubs for their species. They may also be key to saving the animals from angry farmers, the study suggests.

"Hats off to them!" Tim Caro, a behavioral ecologist at the University of Bristol, says of the researchers' work. The study shows the importance of understanding the behavior of wild animals before making conservation management decisions, he notes.

Caro's earlier research served as a starting point for the cheetah study. In the 1980s, he discovered that the big cats have a unique social system among mammals: Solitary females range over huge areas that encompass the smaller territories held by males. Competition among males for their domains is fierce, and they often form coalitions with one or two unrelated males to defend their land. Males without territories (called floaters) roam around looking to take over one of these holdings.

Caro also noted that the male cats had distinct locations, typically a tree or large rock, they regularly marked with their scents. In the new study, scientists led by Joerg Melzheimer, a spatial ecologist at the Leibniz Institute for Zoo and Wildlife Research, realized something important was afoot at these locales.

Between 2007 and 2018, Melzheimer and colleagues attached radio collars to 106 adult cheetahs living in central Namibia on nearly 11,000 square kilometers of cattle ranches. Territorial males spent half their time at these trees or rocks, marking them frequently with urine, the team found. Meanwhile, floaters visited the sites regularly, but only stopped by to sniff. Females also occasionally checked in, leaving their mark when in estrus. Each such site was typically found in the center of a male's territory and functioned "like a popular bar, where you might have a Better chance of finding mating partners," Melzheimer says.

These hubs were stable over time. Even when new males took over a territory, they used the same scent-marking location as the previous owners.

That could be important from a conservation standpoint. Like most big cats, cheetahs are facing a perilous future. Habitat loss, dwindling prey, and conflicts with people have halved their numbers from 14,000 in 1975 to about 7000 today. Most are now found in eastern and southern Africa on farmlands outside of protected areas; the Asiatic cheetah is nearly extinct.

Although cheetahs aren't known as major livestock killers, they will hunt young calves, particularly if they can't find their own wild prey—antelope, gazelles, impalas, and warthogs. In Namibia and elsewhere, farmers kill cheetahs either preemptively or in retaliation for attacking their livestock or game animals. Such farm-related killings are considered the main threat to cheetahs.

Melzheimer's team collaborated with 35 farmers who had lost stock to cheetahs. Of these, six had a cheetah communication hub on their land, and well-documented cheetah attacks. Melzheimer thought the information the cheetahs gathered at these sites was so important, the cats would not follow the livestock if farmers moved their animals elsewhere. Although the six farmers were skeptical, they agreed to move their herds with suckling calves to areas away from these hubs. The number of calves subsequently lost to predation by cheetahs decreased by 86% on average, the team reports today in theProceedings of the National Academy of Sciences.

That's an "astounding" drop, says Maximilian Allen, a carnivore ecologist at the University of Illinois, Urbana-Champaign, who was not involved in the study. "It seems these findings can be applied in any areas where cheetahs overlap with agriculture and livestock."

Melzheimer concurs. "We've discovered there aren't ‘problem animals,'" he says, but "‘problem areas.'" He adds that "every farmer [in this part of Namibia] who has a communication hub is now implementing our advice," and that additional farmers in the country are participating in the research.

Other cats have different social structures and hubs, so the study won't directly help them. But the work does suggest a new way to think about human-wildlife conflicts—something "definitely worth exploring," Allen says.

*Correction, 8 December, 10:15 a.m.: This article has been changed to reflect the fact that all felines, wild or domestic, mark their territories; they do so differently, though, from cheetahs.