Roman era birds feast on thousands of frogs in England

Scientists from Bournemouth University and the Museum of London Archaeology identified birds of prey as the cause of a mass frog die-off dating back 1,700 years.

Researchers examined 8,000 frog bones discovered in a ditch during the construction of the A14 road between Cambridge and Huntingdon between 2016 and 2018. Dr. Paul Clarkson from Bournemouth University and Dr. Vicky Owens from the Museum of London Archaeology analyzed the damage on the bones to determine how the frogs died.

They concluded that birds of prey, likely short-eared owls and buzzards, hunted and ate the frogs. The team used a new analytical method by measuring the humerus bones of the frogs to determine their age. They found that most of the frogs were young and died during their first winter. The research also explained how human activity shaped the environment for these animals. Radiocarbon dating by the University of Vienna placed the remains in the Roman era.

During this time, people cleared large areas of forest to create pastures for livestock. This created open grasslands where frogs thrived in receding marshes but lost their tree cover, making them easy prey for birds that hunt in open spaces. The researchers believe that seasonal human movement and lower-density activity in the area provided the ideal conditions for this ecological event.