Anyone who spends time by rivers, lagoons and lakes has surely seen it: a large dark shape, motionless on a post or a dead branch, with its wings spread in the sun. The great cormorant (Phalacrocorax carbo) is one of the easiest waterbirds to watch in Italy and also one of the most controversial: as beautiful as it is a little “hated” by those who, like me, love fishing.
How to recognise the great cormorant
It is a large bird: it is 80 to 100 cm long, has a wingspan of about 130-160 cm and weighs around 2-3 kg. The neck is long and sturdy, the bill is strong and hooked at the tip, and there is a yellow patch at its base.
The adult looks almost black, and indeed the Latin name carbo means “charcoal”, but the wing feathers are edged in bronze, which makes them stand out. In the breeding season a white patch appears on the thigh. In their first year of life, on the other hand, young birds have pale feathers on the belly.
Its behaviour also helps to identify it. It swims low in the water with its bill tilted slightly upwards, and often gives a little leap before diving. It is usually silent, though it makes guttural sounds in its colonies.
Great cormorant or pygmy cormorant?
The most obvious difference is size: the pygmy cormorant measures 45-55 cm, about half the size of a great cormorant, and has a wingspan of 80-90 cm. On the coast you may also come across the European shag, which is smaller and slimmer than the great cormorant and has a thinner bill.
Why do cormorants spread their wings?
Unlike many waterbirds, the cormorant has plumage that is not fully waterproof and so gets wet when it dives. It may seem like a flaw, but it helps the bird go down faster and chase fish. The price is that it has to dry off after fishing, which is why you so often see it in the sun or wind with its wings spread.
How it fishes and how much fish it eats
The great cormorant catches fish by chasing them underwater and seizing them with its hooked bill. Dives often last 20-30 seconds and can exceed a minute. They usually take place a few metres down, but it can go deeper than 10 metres.
It is a very voracious animal: its needs are estimated at about 400 to 700 grams of fish a day, which can be around a fifth of its body weight. Its diet varies widely from place to place because it tends to follow the fish available. A study of three lakes in Lazio, based on analysing pellets (regurgitated balls of undigested remains), found mainly sand smelt, mullet and cyprinids at Lake Fondi, sand smelt and cyprinids at Bracciano, and pumpkinseed at Vico.
Where it lives and where to watch it
It frequents coasts, lagoons, estuaries, lakes and large rivers, and can even venture into cities: it has been studied, for example, along the urban stretch of the Tiber in Rome. In Italy it occurs as a migrant and winter visitor in every region, while it breeds in a more limited number of places. Winter is therefore the best time to watch it.
The great cormorant is a very social species: at dusk it gathers, sometimes in hundreds, at “roosts” in large trees near the water, where it spends the night. Watching them arrive from a respectful distance is one of the best ways to observe it without disturbing it.
How and where it nests
It nests in colonies, on trees and cliffs near aquatic habitats rich in food for its young, sometimes alongside herons. The nest is a large platform of branches, in which 3-4 eggs are usually laid. Incubation lasts about a month. Where a colony stays for a long time, the accumulated droppings can end up killing the trees that host it.
Is the cormorant a protected species?
Yes. By the late 1970s, after long persecution, only a few thousand pairs were left in Europe. The Birds Directive has protected it since 1979 and the species has recovered, so much so that it was later removed from Annex I, the list of species requiring special conservation measures. Today Europe is estimated to have between 1.5 and 2 million individuals, and breeding pairs in Italy have also increased, from about 880 in 2000 to more than 3,000 according to a 2022 document.
In Italy the cormorant cannot be hunted, but the regions can authorise culling under derogation to limit damage, with specific plans and the involvement of ISPRA, the national environmental institute. In 2026 ten European Union countries asked for it to be added to the list of huntable species, while the Commission pointed out that the current rules already allow action and that non-lethal methods should be tried first.
Why is the cormorant so controversial?
The problem is real above all where fish are concentrated and easy to catch, such as in fish farms, fishing lagoons and small basins. Even a fish that is only injured can become unsaleable. In watercourses, predation on prized species such as the marble trout can also be a concern.
The picture, however, changes from place to place. Several European studies have not found a general depletion of fish in natural habitats, and in the Lazio lakes mentioned above a good share of the prey consisted of abundant species, including some non-native ones. Environmental groups also point out that other factors weigh on fish populations. As a fishing enthusiast I understand the frustration, but it is worth looking at the data for each individual habitat before putting all the blame on the cormorant.
You can find more encounters with birds in mybird gallery and in the article on the common kingfisher, another skilled fisher of our waterways.
