International Guillemot Appreciation Day: Common Guillemot

The 27th June is International Guillemot Appreciation Day. To mark this, and the 350th anniversary of Francis Willughby’s Ornithologia, this post focuses on the description in Ornithologia of the Common Guillemot.

In Ornithologia, Willughby provided various local names for this species. He noted that the Welsh and the Manx called it a Guillem. Those in Northumberland and Durham called it a Guillemot or Seahen. Around Scarborough in Yorkshire it was called a Skout and, finally, the Cornish called it a Kiddaw. Willughby and John Ray believed it to be the same bird described under the name of Lomwia Hoieri by Carolus Clusius. In 1763, Erik Pontoppidan gave it the official taxonomical name of Colymbus aalge and it was later moved into the genus Uria to give the modern binomial name of Uria aalge.

Guillemot in Francis Willughby's Ornithologia

In Ornithologia, the Guillemot was described as having a length, from bill to tail, of 18½ inches (46.9cm) with a wingspan of 30 inches (76.2cm). The bill was straight, sharp-pointed and black and the inside of the mouth was yellow. The feet were situated very far back and were of a black colour, as were also the claws, and it lacked the back toe. Its head, upper side of the neck, back, wings, tail and beside the chin as far as the middle of the throat were of a dark brown or a blackish-ash colour. Its belly, breast and the rest of its throat were white. The tips of the 11 outermost prime wing feathers were white. The tail was 2 inches long (5cm) and consisted of 12 feathers. The middlemost tail feathers were the longest and the rest by degrees were shorter.

Common Guillemot (subspecies albionis) off Skomer Island, Pembrokeshire, Wales, 2021. Photograph taken by Charles J. Sharp, CC BY-SA 4.0, via Wikimedia Commons.

Willughby and Ray also noted in Ornithologia that Mr Ralph Johnson of Brignall in Yorkshire observed and reported to them that these birds varied somewhat in colour with some having black backs, some brown or bay. Willughby wondered whether the difference was due to the sex of the bird but he was incorrect. The modern explanation for this is because they were observing different subspecies. Around England, Wales and the Isle of Man the subspecies Uria aalge albionis is dominant and it is dark brown in colour. However, the dominant subspecies in Scotland, Faroe Islands and Iceland is Uria aalge aalge, which is a sooty-black colour. The area where the two subspecies overlap is around Northumberland and the Farne Islands and thus Mr Johnson had seen both subspecies.

Guillemots (Uria aalge) by Anne Burgess (subspecies aalge), 2016, CC BY-SA 2.0, via Wikimedia Commons.

The Guillemot lived together with the Razorbills and Puffins, breeding in the same manner and in the same places. It bred yearly on the steep cliffs and inaccessible rocks of the Isle of Man, likewise on Godrevy Island not far from St Ives in Cornwall and also on Prestholm Island (Puffin Island), which was about a league (about 3 miles) from Beaumaris on the Isle of Anglesey. Furthermore, this bird frequented and, in the summer months, built its nest on the Farne Islands near the coast of Northumberland and the cliffs around Scarborough. The eggs of this bird were more than 3 inches long (7.6cm), very sharp at one end and blunt at the other and of a bluish green colour and some were varied with black spots or strokes.

Further Reading: John Ray, Francis Willughby's Ornithologia, 1678, p.324, T65.

Author - Debbie Jordan, Middleton Hall Volunteer.

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