330-million-year-old burrows discovered in the Burren, Co Clare 

The discovery was made by Dr Eamon Doyle, geologist for the Burren and Cliffs of Moher UNESCO Global Geopark and Clare County Council.

A piece of history has been uncovered in Co Clare as abandoned fossil burrows dating back 330 million years have been found in limestone rock on the coast of Doolin.

The burrows date back to 100 million years before the appearance of the first dinosaurs and come from a time when Clare had a climate that was very different to the West coast weather we are currently used to.

During this period, the county was located near the Equator and looked and felt a lot like the Bahamas today.

The discovery was made by Dr Eamon Doyle, geologist for the Burren and Cliffs of Moher UNESCO Global Geopark and Clare County Council. Dr Doyle said the burrows were excavated by marine creatures in a very shallow sea.

They are the oldest known occurrence of this particular type of fossil burrow anywhere in the world.

An abandoned fossil burrow in County Clare dating back 330 million years. Image: Dunphy Communications

“The abandoned burrows are filled with coarse sand made of fossil debris and were most likely filled in during a storm event that moved large amounts of coastal sand around,” Dr Doyle explained.

This storm may have forced the creatures to abandon their burrows, he said.

The particular type of fossil burrow is known as Psilonichnus and they are considered to be trace fossils, which is the remains of the activity of a creature rather than the remains of the creature itself.

"The burrows are most similar to the burrows of modern shrimp and crabs, however, while early relatives of shrimp had evolved at that time and are the most likely makers, crabs didn't evolve until millions of years later,” Dr Doyle said.

"As no burrowing creatures were found in the burrows it must remain an open question as to who actually made the burrows, for now. The investigation continues," concluded Dr Doyle.

An artist's impression of an abandoned fossil burrow in County Clare dating back 330 million years, 100 million years before the appearance of the first dinosaurs. Image: Dr John Murray, NUIG

Pat Dowling, Chief Executive of Clare County Council said the discovery, along with previous discoveries, highlight the “uniqueness” of the ancient landscape in the Burren.

“Clare County Council is pleased to support the work of the Burren and Cliffs of Moher UNESCO Global Geopark,” he said.

A research paper entitled “The earliest occurrence of the ichnogenus Psilonichnus: a new record from the Mississippian of the West of Ireland” co-authored by Dr Eamon Doyle is published in the international scientific journal, Ichnos.