Meet the ancestors

Get to know two very similar water birds. Two birds that betray an evolutionary link to dinosaurs more obviously than other birds are cormorants and shags.

With their distinctive upright stance, black plumage and long necks, these two somewhat prehistoric looking birds can easily be confused.

However, there are some key differences both in look and behaviour. Follow these tips and you’ll soon get to know which is which.

Cormorant

Cormorants can be found on the coast and inland, where they fish in rivers and lakes. These are the birds famed for their Liver Bird pose, resting on a rock, wings outstretched, nobly surveying the water around them. Cormorants are larger than shags.

Identification

  • Large bird with black feathers
  • Stronger thicker bill than shag and flatter head
  • Large white cheek patch and prominent yellow patch in juveniles
  • During breeding season, adults have a white leg patch
  • In flight neck looks thick and kinked

 

Flight

Cormorants are rather goose-like in flight, although they tend to have a shallower wingbeat which is broken by short glides. Watch for them flying low over water.

Behaviour

Look for cormorants along the coast and on inland waters, diving and resurfacing a few feet away as they fish for food. You can also see them perched, wings outstretched, as they dry their feathers.  

Nesting

Cormorants can be found around the coast, where they nest on cliff ledges. Increasingly though they are also commonly seen inland, with many choosing to nest in trees near lakes, rivers and gravel pits. Outside of the breeding season, they will often gather in huge communal roosts in trees – reminiscent of a rookery. Intriguingly, “morvran”, a Cornish name for cormorant translates as sea crow.

Where to look

Wherever there is water it is worth a look, as these adaptable birds can be found both inland and on the coast. Look out for cormorants on rocky shores, coastal lagoons, estuaries, reservoirs, lakes and gravel pits.

Shag

Smaller than cormorants, shags are true seabirds and are only rarely seen inland. In the breeding season adults have a prominent crest on their heads – the “shag” of feathers that gives then their name.  

 

Identification

  • Dark, glossy plumage – adults have a greenish tinge during the breeding season
  • Slender bill either dull yellow or dark in colour
  • More rounded head than cormorant with crest of feathers
  • Adults have prominent yellow gape (base of bill)
  • In flight neck looks narrow and straight

Flight

Shags can also be seen flying close to the water, but without the brief glides that characterise cormorants.

Behaviour

Watch for shags sitting out at sea on rocks. They will often sit with cormorants so look for their crests and smaller, more delicate build. They can also be seen fishing, diving with a leap from the surface of the water.

Nesting

Shags nest in loose colonies on coastal cliffs. They are not as widespread as cormorants, with more than half of the UK shag population found at fewer than 10 sites, mainly in the north and west.

Where to look

In Scotland, there are large colonies on Orkney, Shetland, the Inner Hebrides and the Firth of Forth. Elsewhere they can be seen around the coasts of Wales and South West England (especially Devon and Cornwall).

Helping shags to thrive

Shag video screenshot

European shags are one of our less-loved seabirds – but they’re in trouble. Laura Bambini, Seabird Recovery Officer, reports on the work we're doing to help them.

Blue tit (l), Great tit (m) and Coal tit (r) | The RSPB

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