Why Does a Hawk Build with Green Nesting Material? Author(s): Bernd Heinrich Source: Northeastern Naturalist, 20(2):209-218. 2013. Published By: Eagle Hill Institute DOI: http://dx.doi.org/10.1656/045.020.0202 URL: http://www.bioone.org/doi/full/10.1656/045.020.0202

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Why Does A Hawk Build With Green Nesting Material? Bernd Heinrich* Abstract - Most hawks construct the frame of their nest from coarse dry branches and OLQHLWZLWK¿QHUPDWHULDOVEHIRUHWKHHJJVDUHODLG+RZHYHUButeo platypterus (BroadZLQJHG +DZN  DQG VRPH RWKHU KDZN VSHFLHV UHVXPH WR EXLOG RQ WKH QHVW OLQLQJ LQ WKH QHVWOLQJVWDJHE\DGGLQJIUHVKVSULJVRIJUHHQYHJHWDWLRQ9DULRXVK\SRWKHVHVIRUWKHODWWHUEHKDYLRUKDYHEHHQVXJJHVWHG,H[DPLQHGWKHFRQWHQWVRID%URDGZLQJHG+DZNQHVW LQZHVWHUQ0DLQHUHSHDWHGO\WRJDLQLQVLJKWVLQWRWKHIXQFWLRQRIWKHJUHHQVSULJV7KH ELUGVDGGHGRQDYHUDJHWZRODUJHIUHVKJUHHQIURQGVHDFK±FPLQOHQJWK SHUGD\ WRWKHQHVWGXULQJWKH¿UVWGD\VDIWHUWKHLU\RXQJKDWFKHGDQGWKH\FRQWLQXHGWRDGG DERXWIURQGWZLJZLWKIUHVKOHDYHVSHUGD\GXULQJWKHODVWGD\VWKHFKLFNZDVLQWKH QHVW7KHVHIUHVKJUHHQVFRQVLVWHGRIWHQVSHFLHVRISODQWVLQFOXGLQJ¿YHVSHFLHVRIIHUQV DQGWZRVSHFLHVRIFRQLIHU2IP\QLQHH[DPLQDWLRQVRIWKHQHVWLQDOOEXWWKHODVWRQH the nest mold was lined with either ferns or Thuja occidentalis1RUWKHUQ:KLWH&HGDU  ,FRPSDUHGWKHSHUFHQWDJHVRIWKHVHJUHHQVZLWKWKHLUORFDODYDLODELOLW\QHDUWKHQHVWDQG FRQFOXGHWKDWWKHELUGVVHOHFWHGIRUDÀDWEXWIHDWKHU\OHDIVWUXFWXUH7KHOLWHUDWXUHVXJJHVWVYDULRXVSRVVLEOHIXQFWLRQVRIJUHHQHU\LQQHVWV,GLVWLQJXLVKEHWZHHQJUHHQVDGGHG RQWRWKHQHVWDQGJUHHQVDGGHGODWHURQSRVWKDWFKLQJLQWRWKHQHVWOLQLQJDVDOD\HUDQG FRQFOXGHWKDWQHVWK\JLHQHLVWKHPRVWSODXVLEOHH[SODQDWLRQIRUJUHHQYHJHWDWLRQLQKDZN QHVWOLQLQJV

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