Sefton Coast Wildlife

Garden Tiger Moth

Arctia caja

UK Amber ListEasy to see📍 Formby NT Pinewoods
Season
July–August. One generation.
Best time of day
After dark — nocturnal; caterpillars visible in spring and summer
Sefton Coast
Present in dune scrub; most obvious as the hairy 'woolly bear' caterpillar
UK population
Declining significantly — amber-listed; formerly very common

Tap image to enlarge · Wikimedia Commons

Overview

The Garden Tiger Moth has declined by around 90% in Britain over the last 50 years — one of the steepest declines of any moth, linked to climate change (warmer, wetter winters killing overwintering caterpillars). It used to be one of the most familiar moths of gardens and countryside. The adult is spectacular — brown and white mottled forewings, vivid orange-red hindwings with black spots, red-and-black body. The hairy black caterpillar is the 'woolly bear' familiar from paths in late summer.

At a Glance

OrderLepidoptera
FamilyErebidae
HabitatDune scrub · Rough grassland · Garden · Hedgerow
DietAdults: minimal. Larvae: nettles, dock, plantain — the 'woolly bear' caterpillar.
UK populationDeclining significantly — amber-listed; formerly very common
Sefton CoastPresent in dune scrub; most obvious as the hairy 'woolly bear' caterpillar
ConservationUK Amber List

Where to See It

Dune scrub and rough grassland with nettles and dock throughout the Sefton Coast.

Identification

Large moth. Brown and white mottled forewings. Vivid orange-red hindwings with blue-black spots. Red-and-black abdomen. Very striking. Caterpillar: hairy, black with red-orange sides ('woolly bear').

Viewing & Photography Tips

The hairy 'woolly bear' caterpillar crossing paths in late summer is often the first sign — the adult flies in July and August and comes to moth traps.

Conservation Status

UK Amber List

This species is of moderate conservation concern. Population monitoring and habitat management on the Sefton Coast support its continued recovery.

Frequently Asked Questions

Why has the Garden Tiger Moth declined so dramatically?

The Garden Tiger Moth overwinters as a small caterpillar and is vulnerable to mild, wet winters — conditions that cause drowning, disease and inability to survive extended warm periods. As UK winters have become milder and wetter due to climate change, winter survival of caterpillars has plummeted. This is one of the most clearly documented cases of climate change directly driving moth decline.

Related Species

Plan your visit to the Sefton Coast

Marshside RSPB, Formby pinewoods, Ainsdale NNR — practical guides to getting there, what to bring, and the best spots for each season.