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They may be small, but these creepy crawlies are a vital part of our ecosystem. From bright blue butterflies to bees that burrow beneath the ground, what can you spot from the towpath?
Our canals are teeming with insects – from the buzzing buff-tailed bumblebee to the elusive emperor dragonfly, these canal insects play a crucial role in supporting the local wildlife. So, what are the most common insects on UK canals?
Bombus terrestris
The largest of the common bumblebees, buff-tails are regularly seen buzzing from flower to flower in the summer. Buff-tailed bumblebee identification can be easy once you spot its distinctive markings.
Appearance: One of the most recognisable canal insects, buff-tailed bumblebees are about 2-2.2cm with a yellow band on the collar and the abdomen. Queens have a buff-coloured tail, giving the bees their name, while workers have white tails. Males have black facial hair with buff-tinged tails.
Behaviour: Buff-tailed bumblebees have short tongues, so often feed on open flowers, like daisies, to more easily reach its nectar.
Where to see: Often found in lowland areas, buff-tailed bumblebees are widespread and common. Their queens are some of the first to emerge in the spring.
Lucanus cervus
Known for its impressive jaws, the stag beetle gets its name from it's deer-like behaviour when the male uses its powerful jaws to fight off rivals when mating. The stag beetle is one of the common canal insects in the UK, often found in decaying wood along canal banks.
Appearance: Males have massive antler-like jaws and red-brown bodies; females are smaller and have similar brown wings.
Behaviour: Despite their large jaws, the stag beetle's bite is actually quite weak and are relatively harmless to humans.
Where to see: Stag beetles like to nest in dead and rotting wood – they're largely found in the south of England. Our conservation efforts in areas like Caen Hill's Diamond Jubilee Woods and Albert’s Memorial Garden in Birmingham aim to provide food and shelter for these creatures, and others.
Coenonympha pamphilus
Small heath butterflies are often spotted near waterways and canals. They're important pollinators, and their presence suggests the health of an ecosystem.
Appearance: With a wingspan of between 3-3.5cm, the small heath is a dull orange-brown colour with a single eyespot near the tip.
Behaviour: On the wing from May to September, small heaths fly close to the ground and spend much of their time basking in the sun or resting on grass stems with their wings closed, making them hard to spot.
Where to see: A highly adaptable butterfly, the small heath is found along our canals in grasslands, heathlands, meadows, woodland edges, and urban areas. They prefer open, sunny environments with short grass where they can bask in the sun.
Cupido minimus
The small blue butterfly is a rare species that thrives in specific canal habitats, and is highly sensitive to changes in the environment. Their presence is an indicator of healthy habitats with abundant kidney vetch.
Appearance: As its name suggests, the small blue is very small, with a wingspan of just 1.6-2.7cm, making it the smallest butterfly in the UK. Males have dusty blue wings with dark edges; females have brown-grey wings.
Behaviour: With a weak, fluttery flight, small blues stay close to the ground and, as such, are often hard to spot.
Where to see: Small blues thrive in open, sunny spaces, like grasslands, quarries and canals. They’re often found where kidney vetch – their preferred food – grows.
Erynnis tages
Often mistaken for a moth, dingy skippers have muted colours and a low, skimming flight.
Appearance: With a wingspan of 2-3cm, the dingy skipper is a small butterfly that’s brown, grey and yellow in colour – giving it the ‘dingy’ appearance that inspires its name. The forewings have faint white spots, and both wings have a scalloped edge.
Behaviour: Adults feed on the nectar of wildflowers, including dandelions, buttercups, bugles and thyme.
Where to see: Dingy skipper prefer open, sunny areas with sparse vegetation – like grassland, heathland and some canal banks. You can often find the dingy skipper butterfly along canal towpaths, where they feed on wildflowers like bird’s-foot trefoil, which is their preferred food as larvae.
Pyrrhosoma nymphula
Easily be confused with small red damselflies, large red damselflies have black legs, while the former has orange ones.
Appearance: The large red damselfly is medium-sized, despite its name. Males are bright red with black bands, while females often appear completely black.
Behaviour: Most adults emerge within three weeks of each other in the early spring.
Where to see: Widespread across the UK, they're often seen in gardens or around ponds, lakes, ditches, and canals – they like wetland habitats, but avoid fast-flowing water. Large reds are the earliest damselfly to appear in April.
Anax imperator
One of the best places to see emperor dragonflies is along your local canal, where they are commonly seen flying high in the air in search of prey.
Appearance: One of the largest species in the UK, the emperor dragonfly measures 7.8cm long. Males are pale blue with a green thorax and black stripe along the body. Females are a slightly duller blue. Both have green-blue eyes and are recognised by their impressive size.
Behaviour: Emperor dragonflies are impressive and large creatures, often eating prey on the wing.
Where to see: These dragonflies are widespread in England and Wales. Often found by canals from May to October, emperor dragonflies are rarely seen far from the water's edge, and can be seen along your local canal or by garden ponds.
Ephemera danica
The common mayfly is often found in UK waterways, especially around unpolluted canals and ponds.
Appearance: These small and delicate insects measure around 1.5-3cm. The common mayfly has broad and transparent wings, short antennae and three long, thin tails. They have a pale green abdomen with brown markings.
Behaviour: Nymphs live in water, feeding on algae and vegetation. As adults, common mayflies don't have functioning mouths. Instead of feeding, adults focus on breeding.
Where to see: The common mayfly is widespread among wetlands, preferring fresh, unpolluted waters.
Tyria jacobaeae
The striking cinnabar moth flies during the day, frequently spotted on canal banks. As caterpillars, they feed on ragwort plants, and are a key species in controlling the spread of this toxic weed.
Appearance: The cinnabar has predominantly black forewings with bright red stripes and vivid red hindwings with black borders.
Behaviour: The adult moths are typically seen from May to July, flying during the day, especially in sunny weather. They’re also active at night and can sometimes be attracted to lights.
Where to see: Cinnabars are mostly found in sunny spots in grasslands, meadows and along canal towpaths and road verges. They’re common where ragwort is abundant.
Most animals on the planet are insects, and there are around 24,000 known species in the UK. But what do they all have in common?
Firstly, insects are all invertebrates. This means they lack a backbone. Remember that not all invertebrates are insects, though – for example, spiders, harvestmen, woodlice, centipedes and millipedes are all invertebrates but not insects.
Secondly, all adult insects have six jointed legs and three main body parts – i.e. a head, thorax and abdomen. They all have an outer armour, known as an exoskeleton, rather than an internal skeleton, like most other animals.
This shield is made from chitin, a complex carbohydrate similar to plant cellulose, and protects the body from drying out, anchors the muscles and guards against bacteria and fungi.
These canal insects thrive along the water’s edge, making our canals a perfect spot for wildlife enthusiasts. Look for the buff-tailed bumblebee buzzing from flower to flower or the delicate small blue butterfly fluttering near kidney vetch. Common canal insects, like the stag beetle and dingy skipper butterfly, can often be spotted on sunny days, resting on plants or flying low to the ground.
To identify these creatures, look for their distinctive features, such as the small heath butterfly's single eyespot or the bright red markings of a cinnabar moth. By paying attention to the plants and habitats around you, you can identify these vital pollinators along our canals.
Identify footprints and read fascinating facts about the creatures who make their homes along our canals and rivers
Last Edited: 07 March 2025
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