natural mortality

基本解释

This year, because of the higher natural mortality among pups in the south, Canada's Department of Fisheries has reduced the quota for the hunt to 270,000 seals, from 335,000 last year.
今年由于南部的小海豹自然死亡率较高，加拿大渔业部门已将猎杀海豹配额从去年的335000只减少到270000只。
Evidence suggested that people with bipolar disorderhave a higher mortality from natural causes compared to people in the general population of similar age and gender but without mental illness.
证据表明双相情感障碍患者，比起同年龄同性别的无精神疾病的普通人口，有更高的自然原因引起的死亡率。
A new method for estimating fish natural mortality coefficient(M), based on the extended survivors method, using a catch-at-age data and an abundant index(catch per unit effort, CPUE) was proposed.
基于扩展残存资源量法，提出一种根据分年龄组渔获量以及资源量指数（单位捕捞努力量渔获量，CPUE）求算鱼类的自然死亡系数（M）的新方法。

Whale researchers use population models that factor a species' reproductive rate and its natural mortality to come up with an estimate of how many are likely dying.
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