The Cormorant
The Cormorant is a large, mostly black, social waterbird you might have spotted with its wings spread out near the coast or a body of water. The wingspread of the cormorant is arguably one of the most recognisable characteristics of this bird. Cormorants were once known as birds of the sea, but factors such as overfishing in oceans were a means for utilising areas abundant in fish such as quarries.
The wing spread of this bird was a question for many years. Was this to aid in thermoregulation, balance, digestion, or maybe wing-drying? The bird has been observed by many and the prioritized reason is for drying their feathers after a deep dive to catch fish. The Cormorant feathers are not fully waterproof like some other waterbirds, so having a trick for a quick manual dry will defiantly be beneficial; especially when ensuring the ease of flight in times of danger. These birds can dive for as long as 70 seconds and to depths of 147 feet. Thermoregulation does also come into play as drying off quickly will further ensure the bird's temperature can increase faster.
There are around 30 species of the Cormorant with only 2 here in the UK, The Great Cormorant, and the closely related Common Shag (similar, but noticeably smaller and completely black). The cormorant has a stunning blue sheen to its feathers and a long hooked black and yellow beak.
Cormorants are smart birds and are well-utilised in countries such as Japan. For decades, fishermen have used these fish-catching professionals to retrieve fish for a reward; said to be fish and even massages! In a specific case in Japan, the birds were trained to count to 7 catches and then would receive a meal in return. The birds would refuse to do any more work until they got their prize. Their intelligence proves to be top-class.
Reference:
British Trust for Ornithology. (2015). Cormorant. [online] Available at: https://www.bto.org/understanding-birds/birdsfacts/cormorant. [Accessed: 23 April 2023].
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