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Great cormorant

size:

80-100 centimeters
wingspan: 130-160 centimeters

weight:

between 2.6 and 3.7 kilograms

color:

adult: black with white cheek and yellow throat patch; white thigh patch in breeding season
juvenile: grayish black with a white belly

food:

primarily small fish, such as ruff, gobies, lesser sandeel and juvenile flatfish

threats:

overpopulation, leading to possible fututre regulations to limit the numbers

Dutch status:

nesting bird; seen year round, migratory and winter guest

habitat

freshwater and coastal regions

reproduction:

3-4 eggs, usually nests in large colonies in trees or on rocky cliffs

life span:

11 years (maximum known age: + 23.5 years)

special nature:

often seen sitting in the open air with wings spread wide in order to dry them

  • Dut: Aalscholver (schollevaar, zeeraaf, stinker, butstekker (B), preekheer (B), scholvader (B))
  • Eng: Great cormorant
  • Fren: Grand Cormoran
  • Ger: Kormoran
  • Dan: Skarv
  • Nor: Storskarv
  • Frisian: Ielgoes
  • Ital: Cormorano o Marangone
  • Lat: Phalacrocorax carbo
Great cormorant, Jeroen Reneerkens (jeroenreneerkens@hetnet.nl

Great cormorant

Great cormorants eat fish and are known for their excellent diving skills. They forage in fresh as well as saline or brackish water. They can rotate their eyes, something most other birds are unable to do. Unlike other water fowl, their plumage is not oily. They absorb lots of water, so they need to spread their wings to dry after a swim. This bird has not had an easy life in the Netherlands. Because it was considered a rival for fishermen, they were shot, poisoned, chased away and even hung in huge numbers,

On Texel


In the early part of the 20th century, the cormorant had been exterminated as a nesting bird on Texel. In fact, the great nature conservationist Jac P. Thijsse was present by the happening. In 1999, cormorants started nesting again on the island. Since 2007, their numbers were more than 1000 pairs. They like to nest where spoonbills nest. Texelaars call cormorants 'kontekloppers' (bum beaters). This nickname has to do with the jerky take-off when they want to ascend out of the water. They tend to throw their legs back several times in a row, as if they are getting a running start. After taking off, their rear end repeatedly hits the water.

  • Bad reputation

    Cormorants have suffered greatly due to their bad reputation. In a zoological book dated 1812, the cormorant was described as the following: "The cormorant smells more repllent than all other birds. Its form is disgusting, it sound hoarse and husky and its character is even less."

    In the beginning of the 20th century, even nature conservationists were not happy with cormorants because the trees in which they nested often died from their excrement. There is an anecdote whereby the Dutch nature conservationist Jac. P. Thijsse, together with several school children, disturbed the last nesting pair of cormorants on Texel in 1904 so much that the birds never returned. It took almost a century before the cormorant came back to Texel to nest.

    Since 1985, the cormorant has been a protected bird in the Netherlands. The colonies around the IJsselmeer in particular grew so rapidly that the species was removed from the Red List in 1994. In the meantime, cormorants nest again on various Wadden Islands. Cormorants still fall under protection of the European Bird Directive and other international regulations.

  • Folklore
    Great cormorant, foto fitis, sytske dijksen

    In Northern Norway, cormorants are semi-sacred and a sign of good luck when they gather in one's village. The traditional belief is that those who have died at sea and whose bodies were never recovered spend eternity on the island Utrøst, an island difficult if not impossible for humans to find. However the inhabitants of Utrøst are able to visit their former homes in the form of a cormorant.

  • Foraging
    Great cormorant, foto fitis, sytske dijksen

    Cormorants are often seen trailing small fishing boats, just like gulls. However they don't eat the fish wastes; they dive for the fish that are disturbed during the fishing operation. Cormorants eat any fish they manage to catch. In the Wadden Sea, that means primarily flatfish. Sometimes they are too greedy and suffocate in their own prey. Dead cormorants have been found with a large fish sticking halfway out of their throat. Studies of these dead birds have shown that 48-centimeter long zander is the largest fish cormorants can safely swallow. Larger fish can't pass through their throat.

    Unfortunately, it isn't just the size of the fish that causes swallowing problems. In January 2009, a dead cormorant was found with a fish in its throat. The zander was 46 centimeters long and should not have been a problem swallowing. When the cormorant was investigated, it became clear what the cause of death was. The fish had a bright green hook in its mouth and the hook caught on the upper palate of the cormorant. This prohibited the fish from being swallowed and followed in death.

  • Competition for the fishermen?
    Food choice of cormorants in the Wadden Sea, Ecomare

    Cormorants have always been pursued because one believed that it was a formidable competitor for the fisheries. Fish lovers say that all the kilos of fish the cormorants now consume would otherwise be available for the fisheries. But bird lovers say that cormorants eat mostly species which fishermen are not interested in. In the IJsselmeer, cormorants eat around just as much zander as what people catch. The Productschap Vis (representators for the fishermen) estimate the damage for the IJsselmeer fisheries at around 7.5 million euros per year.

  • Food
    Great cormorant, foto fitis, sytske dijksen

    In the Dutch Wadden Sea, the diet of the cormorant varies per season. In April, they eat both freshwater as well as sea fish. In May, the menu consists mostly of sea fish, such as lesser sandeel, flounder and sole.

  • Protection
    • National legislation: Flora and Fauna Regulation
    • European Agreement: Bird Directive;
    • International: Agreement on the Conservation of African-Eurasian Migratory Waterbirds (AEWA), Bern Convention