Ancient boreal bird fossil discovered in Catalan Prades Mountains after 24,000 years

A new study, led by the Catalan Institute for Human Paleoecology and Social Evolution (IPHES-CERCA) and published in the academic journal Geobios, has found that two caves in Mont-ral, in the southern Catalan Prades Mountains, served as feeding sites and shelter for the bird species pine grosbeak (Pinicola enucleator) more than 30,000 years ago.

The species was native to the Arctic forests of northern Europe, and the findings provide evidence of the cold climate that affected southern Europe during the Pleistocene epoch, or the Ice Age.

The study was conducted by researcher Mario Marqueta with Drs. Rosa Huguet and Josep Maria Vergès of IPHES-CERCA, and Dr. Carmen Núñez-Lahuerta, from the University of the Basque Country (UPV/EHU).

“What we have found in the Prades Mountains is an expectational natural archive that allows us to reconstruct, with great precision, what ecosystems were like during one of the coldest periods of the Ice Age,” said Mario Marqueta, the lead author of the study, in a statement.

He added that the presence of northern birds in Catalonia shows “how profoundly global climate cooling events transformed the habitats of southern Europe.”

Findings from the caves

The research focused on two caves, Cova del Cudó and Cova dels Galls Carboners, in the southern Catalan town of Mont-ral, where researchers analyzed more than 450 bird fossils.

Through detailed taphonomic analysis, the group was able to gain a better understanding of how the remains got there and who their predators were.

In the Cova del Cudó, most of the fossils were of smaller birds. And in 41% of the cases, the bones showed signs of digestion.

According to the study, this suggests that predatory birds such as owls or falcons used the cave as a feeding and resting place.

The Cova dels Galls Carboners, on the other hand, showed a predominance of immature pidgeo remains, suggesting that it may have been a breeding site. Many of the bones had tooth marks, indicating that predators could have been foxes or the Iberian lynx.

The pattern of systematic predation on bird chicks by small carnivores is unusual for European Pleistocene sites, and it “opens new avenues of research into the hunting and feeding strategies” of the small animals in caves.

It also shows that caves had multiple uses and that nesting birds, birds of prey, and carnivores coexisted and competed for resources.

Evidence of extreme climate cooling

Toward the end of the Ice Age, a series of massive ice discharges known as the Heinrich Events took place, causing a sudden cooling of the entire Northern Hemisphere.

The third Heinrich Event, around 30,000 years ago, was particularly intense and transformed southern European ecosystems to landscapes typical of the northern tundra.

At present, the bird lives in the Artic areas of northern Europe, which indicates that the climate of the Catalan area used to be much colder and drier, with open forests and weather conditions much more typical of the north.

Gaining understanding of the Ice Age

The study is part of a broader research project on the ecological dynamics of the Iberian Peninsula during the Ice Age.

“Through taphonomic studies such as this one, we get a better understanding not only of the past climate, but also of the animals’ behavior and their ecological relations,” said Rosa Huguet in a statement.