據(jù)1月15日的《科學(xué)》雜志報道說,，北極濱鳥每年都會精疲力竭地長途遷徙到它們的在荒蕪遙遠(yuǎn)的北極的繁殖地區(qū)?？茖W(xué)家們報告說,，它們這樣做確實(shí)也會得到回報。 這些鳥所下的蛋因此而不容易被狐貍及其它掠食動物吃掉,。 在北極筑巢的鳥具有令人印象深刻的遷徙策略,，例如，它們會從其在南美洲的南端,、非洲和大洋洲的南部的過冬場所飛到其在北極的繁殖場所,。 這些鳥在長途旅行時在體力上所付出的代價已經(jīng)被人們作了深入的研究，人們也對這些鳥是如何設(shè)法完成這一旅行的方式做了大量的研究,。
正如一篇相關(guān)的Perspective文章所寫的,，人們對這些鳥為什么要作如此遠(yuǎn)距離的旅行仍然不清楚。 為了測試掠食行為可能會在較高緯度的地方有所減少這一假設(shè),，Laura McKinnon及其同僚在1500個人工鳥巢中放入了鳥蛋,，并將這些人工巢置放在沿著一段北極地帶的7個濱鳥繁殖場所，該地帶由南至北的長度超過3000公里,。 研究人員對這些鳥巢進(jìn)行了至少2個夏天的監(jiān)控后發(fā)現(xiàn),，處在越北面的鳥巢越不容易受到掠食動物的侵害。 在一篇相關(guān)的Perspective中,，Olivier Gilg和Nigel G. Yoccoz對掠食行為是如何影響北極生物多元性的議題進(jìn)行了詳盡的解釋,。（生物谷Bioon.com）
生物谷推薦原始出處：
Science 15 January 2010: DOI: 10.1126/science.1183010
Lower Predation Risk for Migratory Birds at High Latitudes
L. McKinnon,1,* P. A. Smith,2 E. Nol,3 J. L. Martin,4 F. I. Doyle,5 K. F. Abraham,6 H. G. Gilchrist,7 R. I. G. Morrison,2 J. Bêty1
Quantifying the costs and benefits of migration distance is critical to understanding the evolution of long-distance migration. In migratory birds, life history theory predicts that the potential survival costs of migrating longer distances should be balanced by benefits to lifetime reproductive success, yet quantification of these reproductive benefits in a controlled manner along a large geographical gradient is challenging. We measured a controlled effect of predation risk along a 3350-kilometer south-north gradient in the Arctic and found that nest predation risk declined more than twofold along the latitudinal gradient. These results provide evidence that birds migrating farther north may acquire reproductive benefits in the form of lower nest predation risk.
1 Département de Biologie, Université du Québec à Rimouski and Centre d’Etudes Nordiques, Rimouski, Québec, G5L3A1, Canada.
2 Environment Canada, National Wildlife Research Centre, Ottawa, Ontario, K1A0H3, Canada.
3 Ecology and Conservation Group, Environment and Life Sciences Graduate Program and Biology Department, Trent University, Peterborough, Ontario, K9J7B8, Canada.
4 Département Dynamique des Systèmes Ecologiques, Centre d'Ecologie Fonctionnelle et Evolutive, Centre National de la Recherche Scientifique, Montpellier, France.
5 Wildlife Dynamics Consulting, Telkwa, British Colombia, V0J2X0, Canada.
6 Wildlife Research & Development Section, Ontario Ministry of Natural Resources, Peterborough, Ontario, K9J7B8, Canada.
7 Environment Canada, National Wildlife Research Centre and Department of Biology, Carleton University, Ottawa, Ontario, K1S5B6, Canada.
