Old Oswestry was once the stronghold of the Celtic tribe known as the Cornovii – but earlier this month a new band of citizens took command of its formidable ramparts for the day.

On July 1, naturalists and volunteers scaled the hillfort’s lush slopes in beautiful sunshine on the hunt for wildlife as part of a landmark survey.

Specialists in moths, bats, birds, bees, beetles, spiders and small mammals came from all over Shropshire to take part in the BioBlitz.

The aim was to take a snapshot of the hillfort’s flora and fauna over 24 hours, most likely the first major ecological study in its 3,000-year history.

BioBlitzers young and old foraged carefully for specimens to identify and record, safely releasing collected fauna, including insects, moths and spiders, back on the ramparts.

The findings will update and expand records compiled over the years by experts from the Shropshire Wildlife Trust and Shropshire Botanical Society which both supported the event. Data will also help guide on-going landscape maintenance to ensure it safeguards the hillfort’s archaeological structures and thriving ecology.

More than 400 species of flora or fauna were logged on the day, including an encouraging number not previously recorded.

Experts identified no fewer than 23 spider species, including 16 not listed in existing site data, and 23 beetle species, none of which had been recorded on the hillfort before.

Volunteers also collected samples of diptera – small flies and mosquitos – which is set to add to the species list after analysis by the county recorder.

Clare Knight, the event organiser and an ecologist at Turnstone Ecology, said: “The BioBlitz was a huge success with many different and notable species recorded thanks to a fantastic range of local experts and volunteers kindly giving their time to support the event.

“We are still collating the data but we estimate between 400 and 500 species were recorded, which has far exceeded our expectations and is a brilliant result.”

Anyone interested in future hillfort events or volunteering organised by the Oswestry Heritage Gateway should contact 01691 652918 or email OHGateway@gmail.com