囧研究：早起的鳥兒有蟲吃？可不一定！

The early bird really does catch the worm… but he saves it for dinner.
早起的鳥兒真的是在捉蟲，但卻在晚上才吃掉。

Blue tits, great tits and other small garden Birds scout for food in the morning but only return to eat it in the late afternoon, a study found.
研究發現，藍山雀、大山雀和其他花園鳥類在早上找食，但只在臨近傍晚的時候才吃掉。

The Oxford University researchers believe the strategy allows them to stock up on food while avoiding the clutches of predators.
牛津大學的研究人員認爲，鳥類用這種方式來囤積食物，同時也爲了免於被獵食動物吃掉。

A full belly in the morning would slow them down in the hunt for food and make them easy prey.
要是早上吃飽了的話，在找食的時候飛得慢，容易被獵食動物吃掉。

So they search out food when lean and lithe and then dine in the evening to ensure they have a big enough store of fat to survive through the night.
所以鳥類趁身子輕盈的時候，在早上出去尋找食物，卻在晚上吃掉，這樣能保證體內存儲大量脂肪來過夜。

The ‘early bird’ strategy was revealed in an experiment in which over 2,000 birds were fitted with tiny radio tags which activated when they landed on feeders hidden in Wytham Woods, near Oxford.
針對超過2000只鳥的實驗揭示了這種“早起鳥” 捕食策略方式，試驗中給鳥兒安裝了微型無線電標籤，把餵食器藏在牛津附近的威薩姆森林裏，鳥兒只要落在餵食器上微型無線電標籤就會被激活。

The feeders were moved around over the course of the day and the researchers noted when the birds landed on them. This revealed that the birds were much better at finding the feeders’ new locations in the morning. However, they waited until the afternoon to get tucked in.
白天，研究人員會移動餵食器的位置，觀察鳥兒落在餵食器上的情況。經觀察發現鳥類在早上更容易找到餵食器的新位置。不過，他們等到下午才把捕來的蟲子吃掉。

The researchers said the complex strategy acts as an insurance policy, with birds remaining light yet still able to get enough fat to survive the night. It is particularly important in winter when the risks of predation are high and just one day without food can make the difference between life and death for small birds.
研究人員說，這種捕食策略複雜一些則保險一些，鳥類要在保持身子輕盈的同時還要保證過夜所需的脂肪量充足。 特別是冬季，捕食風險很高，小鳥就一天沒有吃的，就得面臨被餓死的境地。

Zoologist Damien Farine said: ‘Birds have to store body fat to avoid starving during the cold winter nights, but this can make them slower and less manoeuvrable so they are more likely to be caught by predators.
動物學家Damien Farine說：“鳥類體內儲存脂肪爲了免於在寒冷的冬夜裏挨餓受凍，但吃飽了身子不夠靈活就會飛得慢，所以，更有可能被獵食動物吃掉。”

‘So there is a trade-off, where birds need to remain lean enough in order to “outrun” their predators during the day but also store enough fat to survive each night.’ Writing in the Royal Society journal Biology Letters, he added that the study shows that rather than ‘idly waiting’ to until the afternoon, the birds start searching out food in the morning.
“所以，鳥類也要遵循權衡法則，爲了‘逃脫’被捕食動物吃掉，就要保持身子輕盈，還要在白天儲存夠過夜的脂肪。” 該研究報告發表在《英國皇家學會生物學快報》雜誌上，他還補充說，據研究鳥兒們並不是“無所事事”地空等到下午，它們從早上就開始尋找食物。

‘Our results show these birds display very different patterns of food discovery in the morning and afternoon; very few new food sources were found during the afternoon, whereas nearly every new food source we put out during the morning was quickly discovered.
“我們的研究結果顯示這些鳥類在早上和下午找食物的模式大不一樣，在下午很少能找到新的食物源，而我們在早上放出去的食物幾乎每一個新的食物源都很快就被發現了。”

‘It supports the idea of an ‘early bird’ strategy of scouting for food early on so they can return to feast a couple of hours before dusk in preparation for a long winter’s night.’
“這項研究爲‘早起鳥’利用早上找食的策略性方法提供了實驗依據，這樣它們可以趕在黃昏前飛回來吃掉爲度過漫長的冬夜做準備。”