研究顯示，土狼喜歡吃貓和人類的垃圾

研究顯示，土狼喜歡吃貓和人類的垃圾

City-dwelling coyotes will eat just about anything – especially your pet cat.

居住在城市的土狼幾乎會吃任何東西——尤其是你的寵物貓。

According to a collaborative study from researchers at California State University, Northridge (CSUN) and the National Park Service (NPS), canines in Los Angeles are less picky than their suburban and rural cousins, opting to dine on the finer things in life like garbage, fruit, and domestic cats. Such dietary adaptations have contributed to coyotes’ success in urban environments in nearly every city in North America.

加州州立大學(xué)北嶺分校(CSUN)和國家公園管理局(NPS)的研究人員進行的一項合作研究顯示，洛杉磯的狗狗不像郊區(qū)和農(nóng)村的狗狗那么挑剔，它們會選擇吃生活中比較好的食物，比如垃圾、水果和家貓。這種飲食上的適應(yīng)性使得郊狼在北美幾乎每個城市的城市環(huán)境中都獲得了成功。

Madison Dapcevich

“They are omnivores, which means they will eat practically anything that fits in their mouths,” CSUN biology professor Tim Karels said in a statement. “Because they will eat anything, coyotes can live practically anywhere — from downtown LA to the urban neighborhoods around CSUN, to the mountains that surround the region and everywhere in between. While they eat a lot of garbage, they also eat a lot of the fruit found on the ground and, yes, domestic cats.”

“它們是雜食動物，這意味著它們幾乎可以吃進嘴里任何東西，”CSUN生物學(xué)教授Tim Karels在一份聲明中說。“因為它們什么都吃，所以土狼幾乎可以生活在任何地方——從洛杉磯市中心到CSUN附近的城市社區(qū)，再到該地區(qū)周圍的山脈，以及這兩者之間的任何地方。雖然它們吃很多垃圾，但它們也吃很多在地上找到的水果，是的，還有家貓。”

Karels collaborated with biology graduate student Rachel N. Larson, and Justin L. Brown and Seth P. D. Riley of Santa Monica Mountains National Recreation Area, as well as 150 citizen science volunteers to determine what food sources coyotes relied on and how urban coyotes eat differently than those further removed from the city. Researchers dissected scat, the poop of wild animals, found at sites across Los Angeles and the neighboring cities of Westlake Village and Thousand Oaks looking for fur, feathers, bones, seeds, and insects – anything to identify what the animals were eating. They also collected and analyzed whiskers collected by NPS to determine their stable isotope ratios to determine the type and quantity of chemicals from food sources. Their findings were published in PLOS ONE.

Karels與生物學(xué)研究生Rachel N. Larson、圣塔莫尼卡山國家娛樂區(qū)的Justin L. Brown和Seth P. D. Riley，以及150名公民科學(xué)志愿者合作，以確定郊狼的食物來源，以及城市郊狼的飲食與那些遠(yuǎn)離城市的郊狼有何不同。研究人員解剖了野生動物糞便scat，這是在洛杉磯、鄰近城市韋斯特萊克村和千棵棵橡樹上發(fā)現(xiàn)的，尋找皮毛、羽毛、骨頭、種子和昆蟲——任何能確定這些動物吃什么的東西。他們還收集和分析了NPS收集的晶須，以確定它們的穩(wěn)定同位素比率，從而確定來自食物來源的化學(xué)物質(zhì)的種類和數(shù)量。他們的研究結(jié)果發(fā)表在《公共科學(xué)圖書館·綜合》雜志上。

Such dietary adaptations have contributed to coyotes’ success in urban environments in nearly every city in North America. Tim Karels/CUSN

“What we were looking for was corn, which is very distinctive from plants naturally found in Southern California. Corn is the base of the American diet. People eat corn. Corn syrup is used in many processed foods, including bread. Corn is fed to livestock and poultry, which humans, in turn, eat,” said Larsen.

“我們要找的是玉米，它與自然生長在南加州的植物非常不同。玉米是美國人飲食的基礎(chǔ)。人們吃玉米。玉米糖漿用于許多加工食品，包括面包。玉米被用來喂養(yǎng)牲畜和家禽，而人類反過來又吃它們。”拉森說。

“If the coyote whiskers had high levels of carbon-13, which signifies the presence of corn, then it could only have come from coyotes eating lots of human food,” Larson explained. “Needless to say, for those coyotes living in urban Los Angeles, we found they were eating a lot of human food, mostly found in the trash we humans leave behind.”

拉爾森解釋說:“如果土狼的胡須中含有大量的碳13，這意味著玉米的存在，那么這些碳13只能來自于吃了大量人類食物的土狼。”“不用說，對于那些生活在洛杉磯市區(qū)的土狼來說，我們發(fā)現(xiàn)它們吃了很多人類的食物，大部分是在我們?nèi)祟悂G棄的垃圾中發(fā)現(xiàn)的。”

It was thought that both urban and rural coyotes would be shown to eat similar amounts of human-related food. Rather, suburban coyotes were much pickier eaters. Around two-thirds of urban coyotes had evidence of human-related items in their scat as opposed to just one-third of suburban coyotes. In particular, ornamental fruits and cats were eaten by coyotes, though it is thought that most of the cats were feral (but not all). Human trash was not commonly found in the scat but whisker analysis showed that up to 38 percent of both urban and rural coyotes’ diet could be human food leftovers. Though urban coyotes stuck largely to their traditional rabbit and rodent diet, the canines still ate a lot of garbage.

人們曾認(rèn)為，城市和農(nóng)村的郊狼會吃同樣數(shù)量的與人類有關(guān)的食物。相反，郊區(qū)的郊狼更挑食。大約三分之二的城市土狼的糞便中有與人類相關(guān)的物質(zhì)，而只有三分之一的郊區(qū)土狼有此證據(jù)。特別是，觀賞水果和貓被土狼吃，雖然人們認(rèn)為大多數(shù)貓是野生的(但不是所有的)。人類垃圾在糞便中并不常見，但whisker的分析顯示，多達38%的城市和農(nóng)村郊狼的飲食可能是人類的食物殘渣。雖然城市土狼在很大程度上仍以兔子和嚙齒動物為食，但它們?nèi)猿源罅坷?/p>

“Coyotes are part of the urban environment,” said Karels. “We’ve created this ecosystem, it’s a new ecosystem from an evolutionary point of view, but it is one that some species are quickly adapting to. Skunks, raccoons, and opossums have all adapted to living in an urban environment. A carnivore, the coyote, has adapted as well.”

“郊狼是城市環(huán)境的一部分，”Karels說。“我們創(chuàng)造了這個生態(tài)系統(tǒng)，從進化的角度來看，這是一個新的生態(tài)系統(tǒng)，但有些物種很快就適應(yīng)了。臭鼬、浣熊和負(fù)鼠都已經(jīng)適應(yīng)了城市生活。食肉動物郊狼也適應(yīng)了。”