Guerra Patrick A, Parlin Adam F, Matter Stephen F
Department of Biological Sciences University of Cincinnati Cincinnati Ohio USA.
Department of Environmental Biology, College of Environmental Science and Forestry State University of New York Syracuse New York USA.
Ecol Evol. 2022 Nov 16;12(11):e9498. doi: 10.1002/ece3.9498. eCollection 2022 Nov.
How first-time animal migrants find specific destinations remains an intriguing ecological question. Migratory marine species use geomagnetic map cues acquired as juveniles to aide long-distance migration, but less is known for long-distance migrants in other taxa. We test the hypothesis that naïve Eastern North American fall migratory monarch butterflies (), a species that possesses a magnetic sense, locate their overwintering sites in Central Mexico using inherited geomagnetic map cues. We examined whether overwintering locations and the abundance of monarchs changed with the natural shift of Earth's magnetic field from 2004 to 2018. We found that migratory monarchs continued to overwinter at established sites in similar abundance despite significant shifts in the geomagnetic field, which is inconsistent with monarchs using fine-scale geomagnetic map cues to find overwintering sites. It is more likely that monarchs use geomagnetic cues to assess migratory direction rather than location and use other cues to locate overwintering sites.
首次迁徙的动物如何找到特定目的地仍然是一个引人入胜的生态学问题。洄游海洋物种利用幼年期获得的地磁地图线索来辅助长途迁徙，但对于其他分类群中的长途迁徙者，人们了解得较少。我们检验了这样一个假设：北美东部秋季迁徙的初出茅庐的帝王蝶（一种具有磁感的物种）利用遗传的地磁地图线索在墨西哥中部找到它们的越冬地点。我们研究了2004年至2018年地球磁场自然变化时，帝王蝶的越冬地点和数量是否发生了变化。我们发现，尽管地磁场发生了显著变化，但迁徙的帝王蝶仍继续在既定地点以相似的数量越冬，这与帝王蝶利用精细的地磁地图线索来寻找越冬地点的情况不一致。帝王蝶更有可能利用地磁线索来评估迁徙方向而非位置，并利用其他线索来定位越冬地点。
