Aqueous Transport of Gull Nests and Eggs: Taphonomic Implications for Fossil Amniote Nests

Abstract

We report the flooding and transport of glaucous-winged gull (Larus glaucescens) nests and eggs in response to high tides at a nesting colony in Washington State. Affected nests were located on the beach bordering a small marina. Flooding and transport most commonly occurred during very high tides. Nests with eggs, nests without eggs, and eggs without nests were observed floating offshore. Our observations have implications for the interpretation of fossilized amniote nests and eggs, namely that a given fossil nest cannot be assumed a priori to have been preserved in situ without careful consideration of nest structure and lithological features of the preservation site. Also, prior to preservation, a fossil egg or egg clutch may have been transported by a floating nest functioning as a transport vessel, even if at the time of discovery evidence for the nest has disappeared.