北極熊英文介紹(更新版)
【正文】 emale seals Reproduction and lifecycle ? Courtship and mating take place on the sea ice in April and May ? A male may follow the tracks of a breeding female for 100 km (62 mi) or more ? after finding her engage in intense fighting with other males over mating rights, fights which often result in scars and broken teeth ? Polar bears have a enerally polygynous mating system Maternity denning（穴居） and early life ? After mating, the fertilized egg remains in a suspended state until August or September. ? Between November and February, cubs are born blind, covered with a light down fur, and weighing less than kg ( lb), Life expectancy ? Polar bears rarely live beyond 25 years. ? The oldest wild bears on record died at age 32, whereas the oldest captive was a female who died in 1991, age 43. THANK YOU FOR LISTENING BBC之殺戮戰(zhàn)場(chǎng)
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