Jersey's agile frog population jumping back after successful breeding season

  • Conservationists have recorded a strong breeding season for Jersey's agile frog. Picture courtesy of Marco Sonnati and Giovanni Fiorani

Jersey is the only place in the British Isles that the agile frog calls home.

The local 'army', a collective noun for the amphibian, is small compared to our European neighbours. It is thought that anywhere between 80 and 300 adult agile frogs call the island home.

The true scale of the population is hard to measure due to the frog's small size and being predominantly nocturnal.

But what makes this frog different is in its name - it has long legs, allowing it to jump distances up to two metres when escaping predators.

Experts have seen fluctuations in agile frog spawn clumps in Jersey during the last decade. Credit: ITV Channel

Agile frogs begin their breeding season at the start of the year, laying their eggs - known as spawn clumps - in late January and February.

Spawn clumps found in Channel Island ponds can hold anywhere between 400 to 500 individual eggs, whereas those found in Europe can see up to 1,800 eggs in one space.

These eggs will remain in shallow ponds for around two to three months, before turning into tadpoles.

The agile frog faces a lot of challenges in the early stage of its life, at the mercy of several predators.

Tim Liddiard goes to survey Jersey's protected sites twice a week, looking for new frog spawn. Credit: ITV Channel

Tim Liddiard, Environment Manager at Jersey's Natural Environment Department, explained: "Around 95% of the tadpoles are eaten along the way, it's a difficult life for frogs."

But for decades, the department has worked alongside Durrell Wildlife Conservation Trust to help the spawn have a better chance at reaching adulthood.

Tim added: "For the last 20 years, we've been collecting or harvesting spawn clumps to take to Durrell. What that does in effect is that the survival rate increases massively because they have a near 100% success rate and so the recruitment is bumped up massively."

Durrell have been helping to increase survival rates for agile frog spawn for more than 20 years. Credit: ITV Channel

Experts have seen fluctuations in the number of spawn clumps being laid at Ouaisne on Jersey's south-west coast in the last decade, but they are starting to spot a promising climb.

Once the frogs reach adulthood, they play an important role in maintaining Jersey's local environment.

Erin Cowham from the Jersey Amphibian and Reptile Group said: "Agile frogs are an important predator in the ecosystem.

"It predates on a lot of the invertebrates, it keeps their populations down. They also form an important prey for other species, so things like grass snakes and herons.

"Agile frogs are also known as what's called an 'umbrella species', which means that by protecting them and their habitats, you're protecting the habitats of lots of other important species too."

Due to its small stature, the agile frog is seen as a tasty treat for several predators found at Ouaisne.

Erin explained: "It's probably considered to be in the middle of the food chain, perhaps slightly further down.

"It would eat a lot of insects, but the tadpoles are an important source of food for predators, lots of things will eat tadpoles."

Erin Cowham from Jersey's Amphibian and Reptile Group says "agile frogs are an important predator in the ecosystem". Credit: ITV Channel

Islanders are being asked to keep "wild areas" in their gardens and outdoor spaces, not just for agile frogs which are a protected species, but for other wildlife too.

Erin added: "Agile frogs are great natural pest managers. They'll take slugs, they'll take all of those typically unwanted creatures from people's gardens, so there's no need to use pesticides or herbicides.

"Outside of the south-west, toads need our help too. Toads love ponds, so it doesn't matter where you live in the island, a wildlife pond is always a good idea."