Monarch蝴蝶数量几乎达到30年来的最低点;保护论者列举了生境损失、气候变化。 Monarch butterfly numbers hit near 30-year low; conservationists cite habitat loss, climate change.

君主蝴蝶人口大幅下降,接近30年来的最低点。 The monarch butterfly population has seen a dramatic decline, nearing its lowest point in 30 years. 养护者警告说,生境丧失和气候变化是导致这种下降的关键因素。 Conservationists warn that habitat loss and climate change are key factors contributing to the decline. 保护乳草的努力是君主毛虫的主要食物来源,保护其移徙路线对物种的生存至关重要。 Efforts to protect milkweed, the primary food source for monarch caterpillars, and preserve their migration routes are crucial for the species' survival.