我回答里的内容大部分来自于美国一个名为 Clipped Ear Cat Sanctuary (大概翻译为剪耳猫避难所) 的猫咪保护组织。这个组织主要做的事情就是提供无家可归的猫咪一个安全的居住场所，该组织拥有一片私人森林，所有被他们救助的猫咪就被半放养在这片森林里。TNR就是他们的主要救助方式。
首先很重要的一点是他们明确定义了stray cat (流浪猫) 和 feral cat (野猫) 的概念。两者的重要区别就是他们与人的社会化程度。流浪猫是被丢失或被遗弃了的宠物猫。野猫则是那些走丢或被遗弃的宠物猫或其他没有绝育的野猫的后代。 流浪猫适应与人类接触并且很温顺，而野猫则不适应与人类的接触并且通常野性难驯。流浪猫有可能会与主人重聚或被其他家庭领养，而野猫则通常很难或者不可能和宠物猫一样与人类接触。
猫的繁殖速度非常快。猫在5个月大的时候就有可能怀孕了，而一只母猫一年可以产仔两到三次。野猫的幼崽会维持他们的野性，因为他们在幼年期不太可能接触到人类。而猫一旦过了幼年期就再也难以社会化了。这样一来，如果人类不进行干预，野猫的数量就会急速增长。（野猫数量过大的危害这里就不具体讨论了）
而没有人类的照顾，野猫的生存条件实际上是非常糟糕的。母猫在5个月大的时候就可能怀孕而且还可能一年生产两三次。对于年轻的母猫来说，生产如此的频繁让他们更难存活。如果没有人类的干涉，多于一半的猫咪幼崽会死亡。公猫则是因为交配权和领土而经常打斗然后受伤，同时也极易通过咬伤传播疾病给其他猫。
然后就不得不提到TNR-Trap-Neuter-Return(捕捉，绝育，放归)。这里还强调TNR是一种以不伤害猫咪性命为前提的减少野猫数量的策略。同时也可以提高野猫的生存条件，以及保护鸟类，野生动物，和人类。TRN主要是针对野性难驯的野猫，而流浪猫或小部分温顺的野猫还是以领养的救助方式为主。而TNR除了绝育还包括打疫苗以及剪耳朵。
What is ear-tipping and why is it important?
为什么要剪耳朵以及为什么剪耳朵很重要？
Ear-tipping is a widely accepted means of marking a feral cat who has been sterilized. It also often identifies them as being part of a cared colony. Ear-tipping is the humane surgical removal of 1/4 tip of the left ear. The procedure is performed by a licensed veterinarian, typically during the spay/neuter surgery. Ear-tipping is completely safe and rarely requires special aftercare. Ear-tipping is especially important as it prevents an already spayed or neutered cat the stress of re-trapping and more importantly, an unnecessary surgery.
剪耳朵是一种被广泛接受的方法，用来表明该野猫已绝育。剪耳朵同样也表明该野猫所依附的族群受到了照管。剪耳朵是以人道的手术方式减去猫左耳朵尖的1/4。手术由一位持证兽医主刀，通常会和绝育手术一同完成。剪耳朵是完全安全的而且也极少要求特殊的术后照料。剪耳朵尤其重要因为能够防止一只已经绝育的猫咪重新经历被捕捉的压力以及不必要的手术。
Why can't animal shelters rescue feral cats?
为什么动物收容所不能救助野猫？
Animal shelters already care for and try to find homes for thousands of lost, injured, abandoned and relinquished pet cats. Whether the shelter is an independent non-profit organization or is an animal care and control agency funded by the municipality, many do not have the resources to do TNR.
动物收容所已经致力于照顾成千上百只被遗弃的，走丢的，或受伤的宠物猫。不论收容所是独立的非盈利机构或者是政府管控的动物控制中心，许多机构没有足够的资源进行TNR。
Animal shelters that receive complaint calls or calls of concern from the public may attempt to humanely trap and remove feral cats. Or, they may provide information and loan traps to citizens interested in humanely trapping feral cats.
如果动物收留所收到公众大量的投诉或关心野猫的电话，他们也许会试图捕捉并灭除野猫。或者他们会提供信息或捕捉工具给希望人道捕捉野猫的民众。
If there is a local group helping feral cats, the shelter may refer callers to that group.
如果有一个本地的野猫救助机构，收留所也许会介绍给打电话的民众。
Feral cats brought to the shelter, especially those who cannot be identified as members of a known TNRed colony, are likely to be put down right away or after a mandatory holding period. It is difficult to accurately identify a feral cat without a holding period, yet safely caring for a feral cat in a typical shelter cage, is very stressful for a feral cat. In addition, if space is limited at the shelter, an adoptable cat may be put down to make room to hold a feral cat.
被带到收留所的野猫，尤其是那些无法识别是否属于某个已被TNR救助的族群的野猫，通常会被立刻安乐死或者在一段强制收容期之后被安乐死。如果没有强制收容期，通常是很难准确判断一只野猫所属族群的。但是对一只野猫来说，即便是被安全的关在一个普通的收留所笼子里也会带来极大的压力。其次，如果收留所的位置有限，一只有可能被领养的猫咪也许会被安乐死以便于腾出位置来安置野猫。
Would it be better if feral cats were euthanized?
把野猫直接安乐死是不是会更好呢？
Some people feel sorry for feral cats because of their difficult and dangerous life. Others are annoyed by the cats' behaviors and want the cats removed. But many people don't feel that the cats should be euthanized. Even if there were enough people and money to remove and euthanize feral cats, other feral cats would move into the vacant territory to take advantage of the food source and shelter now made available. It's an endless cycle.
有些人同情野猫因为他们艰难而且危险的生活。另外一些人反感野猫的某些行为并且希望除去他们。但是大多数人不认为野猫应该被安乐死。即使我们有足够的人力和资金给一整个族群的野猫安乐死，新的野猫会占领空出来的领地兵并且夺取食物资源和收留所的空位置。这只会是一个无尽的循环。
The alternative is Trap-Neuter-Return. When feral cats are TNRed, their health improves because they no longer have kittens and fight over mates, and nuisance behaviors are greatly reduced or eliminated. The colony's dedicated caretaker provides food, water and shelter, watches over the health of the cats and removes any newcomers for TNR (if feral) or adoption (if tame).
替代方案就是TNR。野猫经过TNR之后，他们的健康状况提高因为他们不再继续生育或者为了交配而打斗。他们惹人厌的行为也会急剧减少甚至消失。整个族群的照顾者可以提供食物、水、和遮风避雨的地方，并且监测野猫的健康以及为新加入族群的猫做TNR或者为温顺的猫咪找到领养。
TNR improves the quality of life for existing colonies, prevents the birth of more cats, and reduces the number of cats over time. Additionally, many groups that provide resources for TNR have calculated that the costs associated with TNR are considerably less than those associated with removal, shelter care, and euthanasia of feral cats.
TNR提高了已经存在的猫族群的生活质量，防止了更多猫咪的出生，并且随着时间推移会减少野猫的数量。另外，许多提供TNR的组织证实TNR的花费比给猫咪搬家、提供收留所或者安乐死要少得多。
