Specimen of the Week 351: The carrion crow

Hello everyone! I’m very sad to say that this is my last Specimen of the Week post because my internship finishes at the end of July. My final specimen is a carrion crow, and it was collected from a road on the Isle of Anglesey, Wales in 1993, and then donated to us in 2008 by the Museum of London. The purpose of the donation was “to fill a gap in the bird teaching material”. Read on to find out more about this magnificent bird…

Bird is the word

The English translation of the carrion crow’s taxonomic name, Corvus corone, is “raven crow” – from the Latin “Corvus” (raven) and the Greek “korone” (crow). Corvus corone was also the original name given by Carl Linnaeus in his groundbreaking 18^th century book “Systema Naturae”. Carrion crows are found throughout Europe and East Asia, and are a very common sight. They have black feathers but closer examination reveals that they possess a greenish-purple sheen. Their wingspan is 84-100 cm and they are 44-51 cm long [1]. Carrion crows will often perch on a high point and call three to four times; here’s an audio recording of their croaking call.

Diet and lifestyle

These birds have a varied diet and will eat carrion (decayed flesh), eggs, small vertebrates, molluscs, insects, and even vegetables and grains in the winter [2]. Sometimes they drop hard food, such as shelled animals and nuts, from a great height to crack them open – more on that later! Carrion crows have a large breeding territory with a nest at the centre. Although they are solitary nesters, they will often work together with their neighbours to fight off threats [3]. Carrion crows start breeding at three years old and form lifelong pairs. Eggs are laid in April and the female incubates them while the male brings them food. Chicks fledge after 35 days but will still stay close to their parents for extra food [4].

Bird-brained

There are many scientific papers about the intelligence of corvids (a family of birds that includes crows, ravens, magpies, rooks, etc.), and crows and ravens have even been called the “earth’s smartest birds”. Crows are able to recognise human faces and will hold grudges if someone has threatened them in the past [5]. Some crows have figured out how to open nuts with very hard shells. They drop the nuts on pedestrian crossings in the hope that a car will run them over, then when the traffic lights turn red, they can safely collect the cracked nuts. You can watch the video of this behaviour here.

Museum conservation

The museum records show that this specimen has gone through quite a few conservation treatments over the past nine years. It has been brushed to remove dust and frass (a type of powdery residue produced by pests), has had its wings adjusted and has been frozen to combat pest activity. Last year, this specimen underwent major treatment as part of our Fluff It Up: Make Taxidermy Great Again project. Its makeover involved:
-A new wooden base
-Extensive cleaning with a museum vacuum
-The removal and replacement of pest damaged feathers
-A replacement toe made from sculpting clay

Very superstitious

I decided to blog about this specimen because today is Friday the 13^th and there are some interesting superstitions surrounding the carrion crow. A fairly well-known fact is that a group of crows is called a murder. Also, an old superstition states that the number of crows you see will determine your luck: one crow is bad luck, two crows are good luck, three crows mean health, five crows mean wealth, and six crows mean death is nearby. However, not all crow superstitions are doom and gloom! In ancient Greece, crows had an important relationship with Apollo, the son of Zeus, and they were also used in divination. If a crow was seen flying from the east or south, it was a favourable omen [6].

Nadine Gabriel is the Museum Intern at the Grant Museum of Zoology

References

[1] Mullarney K., Svensson L., Zetterstrom D. and Grant P. J., 1999. Collins Bird Guide. London: Harper Collins Publishers Ltd.
[2] Lack P., 2010. The Atlas of Wintering Birds in Britain and Ireland. A&C Black
[3] Carrion Crow, BTO – British Trust for Ornithology https://www.bto.org/volunteer-surveys/gbw/gardens-wildlife/garden-birds/a-z-garden-birds/carrion-crow
[4] Wilmore S. B., 1979. Crows, Jays, Ravens and Their Relatives. London: David and Charles Publishers Ltd.
[5] Ravens, Crows, Parrots, and More – Meet the Most Intelligent Birds: https://news.nationalgeographic.com/2018/03/year-of-the-bird-brains-intelligence-smarts/
[6] Crow and Raven Folklore, Magic and Mythology: https://www.thoughtco.com/the-magic-of-crows-and-ravens-2562511