好英语网过剩动物的两难选择：节育或安乐死
Zookeepers around the world, facing limited capacity and pressure to maintain diverse and vibrant collections of endangered species, are often choosing between two controversial methods: birth control and euthanasia.
面临有限的容量和保持濒危物种多样性及活力的压力，世界各地的动物园管理者往往会在两种有争议的方法中选其一：节育或者安乐死。
In the United States, the choice is contraception. Chimps take human birth control pills, giraffes are served hormones in their feed, and grizzly bears have slow-releasing hormones implanted in their forelegs. Even small rodents are included.
美国的选择是给动物避孕。黑猩猩吃人类的避孕药，长颈鹿的饲料中掺有激素，灰熊的前腿被植入缓释型激素。即使是小型啮齿类动物也没能幸免。
Cheryl Asa, who directs the Association of Zoos and Aquariums’ Wildlife Contraception Center at the St. Louis Zoo, said euthanasia was not a comfortable fit for zoos here. “On an emotional level, I can’t imagine doing it and I can’t imagine our culture accepting it,” she said.
美国动物园和水族馆协会(Association of Zoos and Aquariums)设在圣路易斯动物园(St. Louis Zoo)的野生动物节育中心(Wildlife Contraception Center)主任谢里尔·阿萨(Cheryl Asa)说，美国动物园不适合对动物实施安乐死。她说，“感情上，我不能想象这么做，我也不能想象我们的文化能够接受这种做法。”
But in Europe, some zookeepers would rather euthanize unneeded offspring after they mature than deny the animal parents the experience of procreating and nurturing their young.
但在欧洲，一些动物园管理者宁愿等一些过剩的动物仔长大后对其实施安乐死，也不愿剥夺动物父母生育和抚养后代的体验。
“We’d rather they have as natural behavior as possible,” said Bengt Holst, director of conservation for the Copenhagen Zoo. “We have already taken away their predatory and antipredatory behaviors. If we take away their parenting behavior, they have not much left.”
“我们希望它们的行为越自然越好，”哥本哈根动物园(Copenhagen Zoo)的动物保护主任本特·霍尔斯特(Bengt Holst)说道。“我们已经剥夺了它们猎杀和反猎杀天性。如果我们再夺走它们养育的习性，它们就没什么剩下的了。”
So he and many of his European counterparts generally allow animals to raise their young until an age at which they would naturally separate from parents. It is then that zoo officials euthanize offspring that do not figure in breeding plans.
因此，一般情况下，霍尔斯特和他的很多欧洲同行都会让动物自然养育后代，等到小动物和父母自然分开，动物园人员再对那些繁育计划以外的动物实施安乐死。
This spring, the Copenhagen Zoo put down, by lethal injection, two leopard cubs, about 2 years old, whose genes were already overrepresented in the collective zoo population. Leopards are considered near threatened by the International Union for the Conservation of Nature. But as part of a breeding plan to maintain the genetic diversity of this species, the cubs’ fate was determined before they were born.
今年春天，哥本哈根动物园以注射方式，结束了两只约2岁的美洲豹幼崽的生命，原因是它们的基因在整个动物园圈子已经过剩。国际自然保护联盟(International Union for the Conservation of Nature)将美洲豹列为近危物种。但为保持该物种的基因多样性，作为繁育计划的一部分，这些幼崽的命运在出生前就已经被决定。
“We promised the species coordinator that the offspring would never leave the zoo,” Mr. Holst said, meaning they would not be bred with leopards from other zoos. The Copenhagen Zoo, he said, annually puts to death some 20 to 30 healthy exotic animals — gazelles, hippopotamuses, and on rare occasions even chimps.
“我们向物种协调员承诺，这些后代不会离开动物园，”霍尔斯特说，意思是它们不会和其他动物园的美洲豹交配。他说，哥本哈根动物园每年会杀死大约20到30只健康的稀有动物——瞪羚、河马，个别情况下甚至有黑猩猩。
The thinking is that this strategy mimics what would have occurred in the wild, where some 80 percent of feline offspring die from predation, starvation or injury, he said.
他说，这么做的思路是，这种策略模仿了大自然会发生的情况——大约80%的猫科动物后代因猎杀、饥饿或者受伤而夭折。
International guidelines on the ethics of breeding zoo animals have been elusive, in part because philosophies vary, said Dave Morgan, chairman of the Population Management Committee at the World Association of Zoos and Aquariums. The African association of zoos lists euthanasia as a population management tool, whereas the precepts of Hinduism and Buddhism make the killing of even terminally ill animals difficult.
世界动物园和水族馆协会(World Association of Zoos and Aquariums)种群管理委员会主席戴夫·摩根(Dave Morgan)称，有关动物园动物繁育伦理的国际指导原则一直难以出台，部分原因是各地的哲学不同。非洲动物园协会(African association of zoos)将安乐死列为一件种群管理工具，而佛教和印度教的戒律甚至不允许杀死得了绝症的动物。
Both the United States and Europe tolerate the euthanasia of feral cats and dogs. Euthanasia is permitted under the American zoo association’s regulations, but is mainly reserved for ill or elderly animals, said Steve Feldman, the association’s spokesman.
美国和欧洲都允许对野猫和野狗实施安乐死。美国动物园协会发言人史蒂夫·费尔德曼(Steve Feldman)称，根据该协会规定，可以实施安乐死，但主要针对生病或者年老的动物。
Although reliable data on the use of contraception is not kept by zoo associations, officials say that it is much more prevalent in North America but that it is starting to expand in Europe.
尽管动物园协会没有保存关于对动物采取节育措施的可靠数据，但有关人员称，这种措施在北美普遍得多，但也开始在欧洲流行起来。
There was a time when no one could have imagined that contraception would be needed for the Mexican wolf, a species hunted nearly to extinction in the 1970s. Zoos began with only seven survivors and bred a captive colony of nearly 300 wolves, saving the species. Ninety-two were reintroduced into the wild by the federal government starting in 1998, but then four years ago, the government used up the limited space that had been allotted for the program in New Mexico and Arizona.
有一段时间，人们无法想象墨西哥狼也会需要避孕措施，该物种上世纪70年代在捕杀之下几近灭绝。动物园最初只有7只幸存的墨西哥狼，后来通过繁育，形成一个将近300只的笼养群体，拯救了该物种。从1998年开始，联邦政府又将其中的92只重新放回了大自然，但4年前，政府用尽了在新墨西哥州和亚利桑那州分配给该计划的有限空间。
So, for the last four years, birth control has helped the zoos breed selectively to maximize genetic diversity but not run out of holding space.
因此，过去4年间，动物园利用节育措施，选择性繁育墨西哥狼，以最大限度提高基因多样性，同时不用尽放养空间。
Genetic diversity is key to long-term species survival because it prevents inbreeding and preserves a broad array of traits that animals might one day need to survive in the wild.
基因多样性对物种的长期生存有关键作用，因为它防止了近亲繁殖，保留了动物也许有朝一日在野外生存所需的各种习性。
Terry Maple, the former director of Zoo Atlanta and co-editor of “Ethics on the Ark,” said that by meticulously planning their populations, zoos will eventually avoid a surplus of animals and ensure that most breed and raise offspring. “I am not saying management euthanasia is wrong,” he said. “It is just not the best solution.”
亚特兰大动物园(Zoo Atlanta)前园长、《方舟上的伦理》(Ethics on the Ark)联席主编特里·梅普尔(Terry Maple)说，通过精心的种群管理计划，动物园最终将能避免动物过剩，并保证多数动物能够繁衍并养育后代。“我并没有说有管理的安乐死是错误的，”他说道。“只不过它不是最好的解决办法。”
Contraceptive science for most exotic animals, Dr. Asa notes, is not as advanced as for apes, which are more closely linked to humans. And side effects can and do occur. Large cats and canines on early hormonal implants were susceptible to uterine infections and tumors. Other animals like elephants have trouble restarting their reproductive cycle once they come off birth control.
阿萨指出，面向多数稀有动物的避孕科学，不如面向猿这种和人类较为相近物种的避孕方法先进。副作用是可能而且确实会有的。早期被植入激素的大型猫科和犬科动物的子宫容易感染，并产生子宫肌瘤。大象等其他动物则在停止节育措施后难以重启其生殖周期。
European zoos that prefer euthanasia cite health risks of contraception as well as the enrichment of parenting — although putting down an animal can sometimes be controversial.
更愿意采用安乐死的欧洲动物园指出，避孕措施带有健康风险，而养育有助于丰富动物的体验——尽管杀死一只动物有时可能引发争议。
Denmark embraces the policy and is very open about educating its public. Germany, by contrast, allows euthanasia only in “reasonable” circumstances, which can be hard to define, said Lesley Dickie, executive director of the European Association of Zoos and Aquaria.A few years ago at Zoo Magdeburg in northern Germany, it was discovered that a male tiger was a hybrid of two tiger subspecies, rendering the cubs it had sired genetically useless. When the three cubs were born, the zoo euthanized them immediately.
丹麦拥护安乐死政策，并且十分坦诚地教育公众。与此形成反差的是，据欧洲动物园和水族馆协会(European Association of Zoos and Aquaria)执行主任莱斯利·迪基(Lesley Dickie)介绍，德国只允许在“合理”的情况下实施安乐死，而这一点可能很难界定。几年前，在德国北部的马格德堡动物园(Zoo Magdeburg)，一只雄老虎被发现是两个老虎亚种杂交的产物，这意味着它尚未出生的幼崽在基因意义上无用。三只虎崽出生后，动物园便立即对它们实施了安乐死。
Dr. Dickie characterized the decision as “courageous,” but animal rights advocates disagreed and had the zoo director and three employees prosecuted for violating the euthanasia law. They received suspended sentences.
迪基认为那个决定“很有勇气，”但是动物权利倡导者不这么认为，他们推动对动物园园长和另外三名工作人员提起公诉，罪名是触犯安乐死法。这些人被判处缓刑。
Even when zoos wait to euthanize animals until their parents have had a chance to raise them, questions can come up. It might seem suspiciously convenient for zoos to destroy an animal just after it has completed its most adorable phase — given that baby animals are a top zoo attraction.
即使动物园等到动物的父母有机会抚养它们之后再对其实施安乐死，也有可能引发问号。在一只动物度过了它最可爱的时期后杀掉它，对动物园来说似乎两头占便宜（动物幼崽是动物园最大的看点），动机可疑。
But Dr. Holst emphasized that the timing is dictated by nature. Zookeepers know it is time when the young leopards start picking fights with their mother.
但霍尔斯特强调称，什么时候实施安乐死是由自然决定的。当年幼的美洲豹开始试图和妈妈打斗时，动物园管理者就知道是时候了。
“It may be painful for us,” he said, “but more natural to them.”
“对我们来说可能很痛苦，”他说，“但对它们来说这样更加自然。”