Nothing on the Aar is guaranteed—and that is part of the fun. Look for a colour, shape or behaviour before trying to name it. Get closer with your eyes and your zoom: the best sighting is one that does not change the animal’s life.
Mute swan
An orange bill, black knob and massive white silhouette. It feeds mainly on aquatic vegetation and likes to keep a generous bubble of space around itself.
Quick clue
A very long S-shaped neck and a black forehead extending into a knob above the bill.
Mallard
The male has an iridescent green head and a narrow white neck-ring; the female is mottled brown. To reach plants underwater, it tips right up, tail towards the sky.
Quick clue
The blue-violet speculum edged in white on the wing helps identify both sexes.
Eurasian coot
A slate-black body, white bill and white frontal shield. Its long toes have lobes that act like little paddles when it swims.
Quick clue
When taking off, it runs noisily across the water before finally lifting clear of the surface.
Common moorhen
A red bill with a yellow tip, a white stripe along its flank and long greenish toes. It hugs the margins, flicks its tail and quickly slips beneath the vegetation.
Quick clue
Smaller and more colourful than a coot; its raised tail reveals two white patches.
Common kingfisher
A compact body, long bill and dazzling blue back. It waits on a perch before diving for small fish; its flight just above the water may last no more than a second.
Quick clue
Listen for a high whistle, then look for a very low, very fast turquoise arrow.
Great cormorant
A large, dark bird with a metallic sheen, hooked bill and webbed feet. It chases fish underwater before returning to a branch or riverbank.
Quick clue
Wings spread at rest: its signature pose helps with drying and temperature regulation.
Grey heron
A tall grey wading bird with long legs and a lightning-fast jab of the bill. It can remain motionless for many minutes before springing into action.
Quick clue
In flight, it folds its neck into an S—unlike storks, which fly with their necks extended.
Coypu
A large semi-aquatic rodent with a white muzzle, prominent whiskers and orange incisors. It swims quite high in the water, with its head and sometimes its back showing.
Quick clue
Its tail is long and cylindrical—nothing like a beaver’s broad paddle.
Egyptian goose
A goose-like shape, pink legs and chocolate-brown patches around the eye and on the chest. Native to Africa, it readily settles on urban lakes and rivers.
Quick clue
The brown eye patch and large green wing speculum are two striking signatures.
Banded demoiselle
This large damselfly patrols slow-moving water. The male gleams metallic blue-green and has a broad dark band across each wing; the female is more understated.
Quick clue
Its fluttering flight and coloured wings distinguish it from fast dragonflies with transparent wings.
A pocket guide to lookalikes
| Torn between… | Look closely at | The deciding detail |
|---|---|---|
| Coot / moorhen | The bill and forehead | Entirely white on a coot; red and yellow on a moorhen. |
| Coypu / beaver | The tail and waterline | A round tail and visible back on a coypu; a broad, flat tail on a beaver. |
| Heron / stork in flight | The neck | Folded on a heron, extended on a stork. |
| Demoiselle / dragonfly | The wings at rest | A damselfly often holds them together above its body. |
When should you look?
Spring: families make the riverbanks sensitive. Summer: dragonflies, young birds and flashes of blue. Autumn: movement and migration. Winter: more waterbirds, but a less predictable kingfisher.
Stealth mode
Slow down before you get close, keep a wide course, never give chase and let your zoom do the work. If the animal changes direction, calls or flees, you are already too close.
A documented presence, never a promise
On a municipal route published in 2018, a moorhen, a female duck with her young and a pair of swans were observed on the Aar. This is a snapshot, not a permanent inventory. The other profiles cover species suited to Strasbourg’s urban waterways or already photographed by Crusoé Kayak.