Wildlife and Working Animals｜Species / Breeds and Lifespan | Evidence chain

FAQ

Do zoo animals live longer than animals in the wild?

Not necessarily. Most mammals, reptiles and birds do live longer in captivity thanks to veterinary care and the absence of predators, but elephants are an important counterexample: a peer-reviewed study reports that the median lifespan of elephants in European zoos is about half that of conspecifics in protected populations in range countries.

動物園の動物は野生より長生きしますか。 — そうとは限りません。多くの哺乳類、爬虫類、鳥類は確かに獣医療と天敵の不在によって飼育下で長生きしますが、ゾウは重要な反例です。査読付き研究は、ヨーロッパの動物園のゾウの寿命の中央値が、原産国の保護区にいる同種個体群のおよそ半分であると指摘しています。

Do zoo animals live longer than animals in the wild? — Not necessarily. Most mammals, reptiles and birds do live longer in captivity thanks to veterinary care and the absence of predators, but elephants are an important counterexample: a peer-reviewed study reports that the median lifespan of elephants in European zoos is about half that of conspecifics in protected populations in range countries.

Guide dogs work for 8.5 years. Is that their lifespan?

No, that is years of service. The study reports that the majority (84%) of guide dogs retire after about 8.5 years of work. The retirement thresholds for other working roles such as police, search and rescue and detection dogs may differ, and in practice they depend on institutional rules and the degree of occupational wear on the individual.

盲導犬が 8.5 年働くというのは、その寿命ですか。 — いいえ、稼働年数です。この研究は大多数（84%）の盲導犬が約 8.5 年の稼働の後に引退したと指摘しています。警察犬、捜索救助犬、麻薬探知犬など他の使役役割の引退の目安は異なる場合があり、実際には施設の規定と個体の職業的消耗の程度によって異なります。

Guide dogs work for 8.5 years. Is that their lifespan? — No, that is years of service. The study reports that the majority (84%) of guide dogs retire after about 8.5 years of work. The retirement thresholds for other working roles such as police, search and rescue and detection dogs may differ, and in practice they depend on institutional rules and the degree of occupational wear on the individual.

Can I look up one general figure for the lifespan of wild animals?

No, lifespan varies enormously between species. The direction that "lifespan in the wild is generally far shorter than in captivity" broadly holds for most small wild animals, but it is not universal; the allowlisted sources do not provide species-by-species comparison figures, and applying a single ratio of your own is not permitted.

野生動物の寿命は共通の数値を調べられますか。 — できません。寿命は種によって差が極めて大きいためです。「野生下の寿命は飼育下より一般に大幅に短い」という方向性は多くの小型野生動物でおおむね当てはまりますが、どこでも通用するわけではありません。種ごとの比較数値は許可リストの出典に示されておらず、独自に単一の比率を当てはめることも禁じられています。

Can I look up one general figure for the lifespan of wild animals? — No, lifespan varies enormously between species. The direction that "lifespan in the wild is generally far shorter than in captivity" broadly holds for most small wild animals, but it is not universal; the allowlisted sources do not provide species-by-species comparison figures, and applying a single ratio of your own is not permitted.