Abstract:
:Albatrosses (Diomedeidae) do not occur in the North Atlantic Ocean today except as vagrants, although five species were present in the early Pliocene. No fossil breeding sites of albatrosses were known previously. The timing of extinction of albatrosses in the North Atlantic was likewise unknown. Deposits that formed near present-day sea level along the southeastern shore of Bermuda contain remains of a former breeding colony and include intact eggshells and bones of embryos, juveniles, and adults of Short-tailed Albatross (Phoebastria albatrus), a critically endangered species now confined to a few islets in the northwestern Pacific Ocean. These deposits are correlated with the middle Pleistocene Lower Town Hill Formation, which at other sites have a radiometric age of 405,000 years ago. This equates with the marine isotope stage 11 interglacial, which culminated in a rise in sea-level to >+20 m. Bones of a juvenile Short-tailed Albatross were also found in beach deposits at +21.3 m from this same interglacial. We interpret the extirpation of albatrosses on Bermuda as probably resulting from lack of nesting sites protected from storm surges over the little emergent land that remained at the height of the marine isotope stage 11 sea level rise.
journal_name
Proc Natl Acad Sci U S Aauthors
Olson SL,Hearty PJdoi
10.1073/pnas.1934576100keywords:
subject
Has Abstractpub_date
2003-10-28 00:00:00pages
12825-9issue
22eissn
0027-8424issn
1091-6490pii
1934576100journal_volume
100pub_type
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