北方豹蛙在3月至6月的春季繁殖。男性采取打鼾般的隆隆声来吸引女性。一旦雌性选择雄性,该对配对一次。交配后,雌性在水中产下多达6500个卵。鸡蛋是凝胶状的,圆形,中心较深。卵孵化成淡褐色的蝌蚪,有黑色斑点。孵化和发育的速度取决于温度和其他条件,但从卵到成虫的发育通常需要70到110天。在这个时候,蝌蚪会变大,发展肺部,长腿,并最终失去尾巴。世界自然保护联盟将北方豹蛙的保护状况归类为“最不关心”。研究人员估计,数十万或数百万只青蛙生活在北美洲。然而,自20世纪70年代初以来,人口一直在迅速下降,特别是在落基山脉。实验室研究表明,区域衰退的可能解释与高于正常温度对拥挤和细菌感染的影响有关。其他威胁包括栖息地丧失,引入物种(特别是牛蛙)的竞争和捕食,农业化学品(例如阿特拉津)的激素效应,狩猎,诱捕研究和宠物贸易,污染,恶劣天气和气候变化。

加拿大新斯科舍Essay代写:激素效应

Northern leopard frogs breed in the spring from March to June. Men use a snoring rumble to attract women. Once the female selects the male, the pair is paired once. After mating, the female produces up to 6,500 eggs in the water. Eggs are gelatinous, round and deep in the center. The eggs hatch into a pale brown sputum with black spots. The rate of incubation and development depends on temperature and other conditions, but it usually takes 70 to 110 days to develop from egg to adult. At this time, the cockroach will grow bigger, develop the lungs, long legs, and eventually lose the tail. The World Conservation Union classifies the protection of northern leopard frogs as “the least concerned.” Researchers estimate that hundreds of thousands or millions of frogs live in North America. However, the population has been declining rapidly since the early 1970s, especially in the Rocky Mountains. Laboratory studies have shown that the possible explanation for regional recession is related to the effects of higher than normal temperatures on crowding and bacterial infections. Other threats include habitat loss, competition and predation of introduced species (especially bullfrogs), hormonal effects of agricultural chemicals (such as atrazine), hunting, trapping research and pet trade, pollution, bad weather and climate change.

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