動物園のゾウの生存率が損なわれている
Ros Clubb1, Marcus Rowcliffe, Phyllis Lee
1Royal Society for the Prevention of Cruelty to Animals (RSPCA), Wilberforce Way, Southwater, West Sussex, RH13 9RS, UK.
Science (New York, N.Y.)
|December 17, 2008
まとめ
欧州の動物園のゾウは,保護された野生の集団のゾウよりも寿命がかなり短い. この生存のギャップは特にアジアゾウで顕著であり,高乳児死亡率と動物園で生まれた個体では生存率が低い.
科学分野:
- 獣医科学 獣医科学 獣医科学 獣医科学 獣医科学
- 動物学 動物学
- 動物福祉科学 動物福祉科学
背景:
- 動物園の施設にいるゾウは,野生のゾウと比べると,環境や健康上の課題が異なっていることが多い.
- ゾウの長寿に影響する要因を理解することは,保護と福祉の取り組みにとって極めて重要です.
研究 の 目的:
- ヨーロッパ動物園のゾウの平均寿命を,範囲国における保護集団の同種のゾウと比較する.
- 動物園に収容されているゾウ,特にアジアゾウの生存率の低下に貢献する特定の危険因子を特定する.
主な方法:
- 4500頭以上の象のデータを分析した.
- 動物園に収容されているゾウと,保護されている野生のゾウの生存率の比較.
- ゾウの死亡率に影響を与える人口統計的および管理関連の要因の特定.
主要な成果:
- 欧州の動物園のゾウは,保護された野生の集団のゾウの平均寿命の約半分を示しています.
- 動物園にあるアジアゾウは,アフリカゾウとは異なり,幼児死亡率が非常に高く,成人の生存率が停滞している.
- 施設間での象の移動と母親の早期分離は,特にアジアゾウの生存に悪影響を及ぼします.
- 動物園で生まれたアジアゾウは,成人の生存率が低いため,産前または幼児期の影響が示唆されています.
結論:
- 動物園の環境はゾウの生存に重大なリスクをもたらし,アジアゾウは特に脆弱である.
- 機関間移転や人生の初期経験などの管理慣行は,重要なリスク要因です.
- ストレスおよび/または肥満は,動物園ゾウで観察された生存率の低下に寄与する可能性があると提案されています.
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