譯/莊蕙嘉 核稿/樂慧生
加州搶救帝王斑蝶
Known for their windowpane wing design and bright orange color, Western monarch butterflies add a dash of magic to the California coast, where they spend the winter. Now a coalition of conservation groups, the California Department of Fish and Wildlife, and the environmentalist organization River Partners are working together to extend a lifeline to the monarchs, whose population has been dwindling drastically.
西部帝王斑蝶以窗玻璃般的翅膀花樣和鮮豔橘色聞名，為牠們度過冬季的加州海岸增添些許魅力。現在，一個保育團體聯盟，「加州魚類及野生動物管理局」和環保組織「河流夥伴」正攜手合作，為數量急遽減少的帝王斑蝶提供一線生機。
The groups have embarked on an effort to add 30,000 milkweed plants across the state to provide the butterflies with places to breed and acquire the sustenance for migration.
這些組織已展開一項行動，在加州各地增植3萬株乳草，提供蝴蝶繁殖場所及遷徙所需糧食。
The Western monarchs' California population has fallen 99% since the 1980s, The San Francisco Chronicle reported. A major factor in that drop has been a decline in milkweed caused by farming and pesticide use. Milkweed is vital to monarchs as a place to lay eggs and as a food source for their caterpillars.
舊金山紀事報報導，加州西部帝王斑蝶數量自1980年代以來已減少99%，一大原因是，農作和使用農藥使得乳草減少。乳草對帝王斑蝶十分重要，是產卵之處，也是幼蟲食物來源。
Monarch butterflies do something called "overwintering" on the coast of California — spending time there from October to March before migrating farther inland to breed.
帝王斑蝶有所謂的「越冬」行為，在遷徙到更內陸地區繁殖之前，從10月到3月待在加州海岸。
Every year around Thanksgiving, volunteers count the migrating monarchs at the coastal overwintering sites, said Cheryl Schultz, a biology professor at Washington State University who works with the River Partners project. In 2019, 29,000 butterflies overwintered in California. A year later, that number was just 2,000, she said.
和河流夥伴合作專案的華盛頓州立大學生物學教授雪柔•休茲說，每年感恩節前後，志工在沿海越冬地點計算遷徙的帝王斑蝶數目。她說，2019年有2萬9000隻蝴蝶在加州越冬，一年後，數目只有2000隻。
In response, California put forward a $1 million state-funded initiative to restore the Western monarchs' natural habitat — and hopefully the population itself — by planting 600 acres of milkweed statewide.
為因應此一變化，加州祭出由州政府提供100萬美元經費的計畫，透過在州內各處種植600英畝的乳草，重建西部帝王斑蝶的自然棲息地，也希望能恢復數量。
"It's going to take time for that habit to establish," Schultz said. "It's not like we can plant milkweed today and poof, you know, three months from now we have 40 functioning habits for monarchs. Different areas will take different amounts of time to come online."
「那樣的棲息地需要花時間建立。」休茲說，「可不是我們今天種下乳草，然後咻的一下，三個月後就有40個可派上用場的帝王斑蝶棲息處。不同地區需要花不同的時間來達到可用狀態。」
Although monarch butterflies are faced with extinction, the species is not federally protected because other species are a higher priority.
帝王斑蝶雖面臨滅絕危機，卻並未受到聯邦保護，因為有其他物種排在前面。
According to the U.S. Forest Service, milkweed is a wildflower known for being "a mega food market for insects." Almost 500 types of insects, including butterflies, feed on some part of the milkweed plant — its sap, leaves and flowers all provide nutrition.
根據美國國家森林局的資料，乳草是一種野花，以「昆蟲的食物大賣場」聞名。包括蝴蝶在內，將近500種昆蟲以乳草的某個部分為食，它的汁液、葉子和花皆能提供養分。
Schultz said that, aside from being a source of food, milkweed contains cardenolides, enzymes that when digested by monarch caterpillars make them toxic to predators like birds.
休茲說，除了作為食物來源，乳草還含有強心甾，這些酶被帝王斑蝶幼蟲消化後，會使幼蟲對牠們的掠食者如鳥類而言具有毒性。
