Date: Tue, 30 Jan 2001 17:54:32 +0200
Reply-To: Conchologists of America List <CONCH-L@LISTSERV.UGA.EDU>
Sender: Conchologists of America List <CONCH-L@LISTSERV.UGA.EDU>
From: Henk and Zvia Mienis <mienis@NETZER.ORG.IL>
Subject: once more shell throwing birds
Although shell dropping by gulls and crows is well documented, shell dropping by Ospreys is hardly known. However, Ospreys on Tiran Island, at the southern tip of the Gulf of Aqaba, Red Sea, have been seen dropping adult Lambis truncata sebae from a height of 30-40 m on an oildrum filled with cement. According to the numerous broken shells scattered all around the drum they are excellent marksmen. A living adult Lambis has a weight of about one kilogram and should cause quite an impact when dropped from such a height.For the "bibliophiles" among you here are some references:
Ilani, G., & Shalmon, B., 1984. Osprey tactics. Israel-Land and Nature, 9 (2): 81.
Leshem, Y., 1985. Shell-dropping by Ospreys. British Birds, 78 (3): 143.
Mienis, H.K., 1993. [Predation on Lambis truncata sebae by Ospreys on Tiran Island, Egypt.] De Kreukel, 29 (2): 31-32. (Sorry, its written in Dutch!)
Henk K. Mienis
National Mollusc Collection
Dept. Evolution, Systematics & Ecology
Hebrew University of Jerusalem
IL-91904 Jerusalem, Israel