Corey’s recent posts from Europe mentioned the native Red Squirrel and the problems it’s facing from the introduced and more aggressive North American Grey Squirrel. Introduced species are rarely beneficial (eg see Mike’s post on the Common Myna): ecosystems are complex things and build up over thousands of years, and whilst we over here would like to stop the Grey Squirrel from rampaging through our parks, most North Americans in turn would like to see efforts focussed on eradicating the overseas trio of Feral Pigeon, House Sparrow, and Starling from theirs.

The traffic in introduced birds isn’t just across the Atlantic of course, and one species that is currently jumping ship in ports across the world is the House Crow, which ludicrously has been given the scientific name of Corvus splendens: the ‘Splendid Crow’. For those of you thinking that having a ‘Splendid Crow’ in their neighbourhood might not be such a bad thing, read on…

 

One of the first “ticks” that birders from Europe and the US will get on a trip to the Indian sub-continent is the House Crow Corvus splendens. Bold, noisy, abundant and almost totally unafraid of people House Crows fill a similar ecological niche to the more northerly Carrion Crow Corvus corone, but have spread out from rural habitats and are now found in every city, often scrabbling in large flocks through piles of garbage at the sides of roads.

Chennai, southern India

 

In many parts of India House Crows are regarded as beneficial because of their scavenging habits - but in other parts of the world they’re not so welcome. Considered by some to be overly aggressive and detrimental to indigenous bird populations, this intelligent bird is expanding its range considerably. For example, ships passing through the Suez Canal – possibly warships returning from the Gulf War – provided an opportunity for the House Crow to reach Europe. The first European record was from Gibraltar in March 1991, and a small breeding colony has since become established in Holland. House Crows are now in Israel, South Africa, Singapore…the list goes on and non. Whilst the following excerpts are by no means intended to be an exhaustive survey, they perhaps give some indication of why the addition of House Crow to the national bird list might not always be seen as a cause for rejoicing.

 

Dhaka, Bangladesh

 

www.gisp.org/casestudies/S E Asia:
As an avian invader, the Indian House Crow is undesirable for a host of reasons. It is an aggressive and opportunistic feeder, and has a devastating impact on indigenous bird populations by eating eggs and chicks, and mobbing other birds that might compete with it. It threatens the local wildlife by preying heavily on frogs, lizards, small mammals, fish, crabs and insects. The crow was introduced to Malaysia as a biocontrol agent of rhino beetles in oil palm estates.It affects agricultural productivity by stripping fruit trees in orchards and decimating grain crops, eating chicks of domestic poultry, and has even been known to peck out the eyes of sheep and pigs. It is unafraid of humans, and may enter houses to steal food, dive-bomb people walking past the nest, and frighten children by snatching food from their hands. House Crows have also been blamed for causing power cuts in some areas, as they often construct nests out of wire in electric pylons.

rmbr.nus.edu.sg/Singapore:
The House Crow is not an indigenous bird of Singapore. Its natural distribution extends from South Asia which covers Pakistan, India and Sri Lanka to southern China and some parts of Indochina that include southern-western Thailand (Madge & Bum, 1994). This crow has become widespread by introduction or self-introduction to many countries
around the Indian Ocean and other parts of the world. In the 1920s, an attempt to introduce the House Crow in Singapore was unsuccessful (Bucknill & Chasen, 1927). The present established population in Singapore originated from introduced birds that were probably transported by ships from India and Sri Lanka in 1940s (Hails & Jarvis, 1987; Madge & Bum, 1994).

National Geographic, January 2007: “Ripping apart garbage bags, rummaging through leftovers, scavenging cafés and food stands, crows have earned the enmity of sanitation- obsessed Singaporeans. The tiny Asian island nation is infamous for its strict rules to promote cleanliness, including a ban on most chewing gum in public places.
And when it comes to crows, neatness isn’t the only concern, as dive-bombings have been known to leave Singaporeans smarting…”

 

  
Bombay, India

 

www.durban.gov.za/Durban:
Corvus splendens, the Indian House Crow, is an exotic bird, which is rapidly becoming semi-localised in cities along the east coast of Africa. It has become a major problem in countries such as Mozambique, Kenya, Tanzania, Malaysia and Mauritius. The first ever report of its presence in South Africa was in 1972, when a flock of 60 birds was situated at Sodwana Bay. It’s emergence in Durban has come at a time when most Durbanites are aware of the problems created by the Indian Myna infestations. Although there are relatively large numbers of house crows in the Metro area (and further afield), it is still possible to control their numbers effectively, although at this stage total eradication would be preferred.

www.tau.ac.il/Israel:
The Indian House Crow (Corvus splendens) first appeared in Elat in 1976 (Paz, 1987) where about 300 individuals are living presently, and is occasionally seen north of Elat along the Arava Valley.

 

Kolkata, India

 

Additionally, there is a fascinating post on James Wolstencroft’s wonderful blog, Birdman, consisting of email exchanges on the population of House Crows on the Tanzanian coast (where the birds were introduced by British civil servants who apparently hoped they would help keep the streets clean).

 

All photographs on this page © Charlie Moores