A fossilised otter skull trawled from the bottom of the North Sea off the coast of the Netherlands last year is approximately 9000 years old. This otter fossil was found together with the remains of mammoths and other mammals dating from the ice age. 14C dating shows that this carnivore did not live between 50,000 and 30,000 years ago on the Mammoth Steppe in today’s North Sea basin alongside woolly mammoths, rhinos, steppe bison and giant deer, but much more recently amongst ‘modern’ man, European bison, red deer, elk, beavers and wild boar.
This emerges from the article written by Dick Mol and Hans van de Plicht that appears in the March edition of ‘Straatgras’, the journal published by the Natural History Museum Rotterdam. For many years there has been uncertainty as to how old fossilised otter remains from the North Sea basin actually are. The otter (Lutra lutra) is still extant in the Netherlands and Western Europe but is rare.
Mol and Van der Plicht examined a six-centimetre fragment of an otter skull that was trawled on 9 September 2011 by the Eurokotter BRA 7 at a depth of 25 meter in the sand extraction area of the Maasvlakte 2, about 15 kilometres west of the Hook of Holland. The skull was dated using the 14C method in the Center for Isotope Research of the University of Groningen.
Late last year during archaeological research at the site of the present Maasvlakte traces of human habitation dating from the same period as the otters, approximately 9,000 years ago, were found. Both finds confirm the theory that during this period the water and river delta, rich in fish, was teeming with life.
Fishing for fossils
Since 2009 fossil fishing trips to hunt for fossils and archaeological objects have been organised under the auspices of the Port of Rotterdam in the sand extraction area for the Maasvlakte 2, the land reclamation project for the port of Rotterdam. Thanks to the suction hopper dredgers that are opening up new and deeper parts of the sea floor, there have been some particularly spectacular fossil finds: about 350 top-quality mammal remains have been added to the collection of the Natural History Museum.
Three quarters of these come from the woolly mammoth (Mammuthus primigenius), including the longest mammoth thigh bone ever found, two virtually complete and exceptionally large pelvises, and a tusk. Other mammal species from the Late Pleistocene of which fossils have been fished out of the Maasvlakte 2 sand extraction area are reindeer, steppe wisent, giant deer, red deer, woolly rhino, harp seal and cave lion. In 2010 the nets pulled out a first: fossilised hyena dung. The otter skull fished out last year is one of the few finds from the recent geological period, the Early Holocene.
Dredging Today Staff, March 30, 2012; Images: portofrotterdam