Pliocene Right Whale Fossil from Tjörnes, Iceland

The Tjörnes Formation in northeastern Iceland contains the island’s only substantial pre-Quaternary marine sedimentary exposure. Although the formation is known for its rich fossil mollusc record, vertebrate fossils had rarely been documented there.

In July 2011, Dr. Jakob Vinther discovered a partial skull of a large right whale weathering out of a cliff on the western edge of the Tjörnes Peninsula. A Yale Peabody Museum field crew subsequently excavated the fossil.

The specimen, catalogued as IMNH 9598, was found in situ in the middle of the Mactra Zone. It dates to the Pliocene, approximately 4.63 to 3.4 million years ago. The 2017 study identified it as the first whale fossil recovered in situ from the Pliocene Tjörnes Formation and the oldest marine vertebrate fossil then known from Iceland.

IMNH 9598 consists of an isolated right squamosal, a bone from the skull’s temporal region. Its anatomical features identify it as a member of Balaenidae, the family that includes right whales and bowhead whales. Researchers assigned the specimen to cf. Eubalaena, indicating a probable but not definitive relationship to the right whale genus Eubalaena.

The fossil was weathering out of a cliff approximately 7 meters above sea level. To reach it safely, the crew rappelled from a fixed point approximately 30 meters above the specimen. Excavation took roughly two weeks. A pulley system was then used to lower the fossil to sea level before it was transported to the Yale Peabody Museum for preparation.

In the 2017 scientific description, IMNH 9598 was the northernmost Pliocene balaenid then known. Its occurrence also supported the possibility that right whales and bowhead whales occupied broadly overlapping latitudinal ranges during the Pliocene, unlike the more separated distributions of their living counterparts.

Field Documentation

Amanda Fornal assisted the field team and photographed and filmed the excavation. The project produced the documentary short Whale Fossil from the Pliocene of Iceland.

Watch the documentary short

Scientific Publication

The fossil was formally described in 2017 in Palaeontology:

Daniel J. Field et al. “The Oldest Marine Vertebrate Fossil from the Volcanic Island of Iceland: A Partial Right Whale Skull from the High Latitude Pliocene Tjörnes Formation.” Palaeontology 60(2): 141–148. DOI: 10.1111/pala.12275.