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Potential Impacts of Invasive House Crows
(Corvus Splendens) Bird Species in Ismailia
Governorate, Egypt: Ecology, Control and Risk
Management
A. M. Kamel Faculty of Veterinary Medicine, Suez Canal University, Ismailia, Egypt
Email: [email protected]
Abstract—House crows (Corvus splendens) have become
well-established in Ismailia Governorate, Egypt, where they
pose several and serious impacts on native biodiversity,
ecosystems and humans health. However, there is a lack of
literature on the status and effects of invasive birds in Egypt.
Over the past 10 years in Ismailia, House crow have
increased at a rate approaching (60000 birds) 15% per
annum; if this were allowed to continue, the population now
10909 birds and will exceed more by 2014, probably
accompanied by an increase in geographical distribution in
all Suez canal regions and an exacerbation of the problems
caused. Population control is recommended, involving
improvements in urban hygiene and the capture of adult
crows using stupefying baits. Suitable baits and stupefacient
doses were identified and these should be used annually, just
before the breeding season. Control should be accompanied
by studies of relevant aspects of the biology of house crows
in Ismailia Governorate.
Index Terms—environmental impact, non-native invasive
species, house crow birds, risk management, ismailia-egypt
I. INTRODUCTION
The house crow (Corvus splendens) is native to India
and parts of its neighboring countries where it is closely
associated with people and has some negative impacts on
their communities, However, the effects of house crows
are so significant in the 25 or more countries throughout
Africa, the Middle East and South East Asia where the
bird has been introduced [1]-[3], and it is now regarded as
one of the world’s most invasive bird species [4].
Introduced house crows continue to spread across the
region of their introduction [5] with negative effects on
agriculture, tourism, human health, traffic, transport, and
biodiversity [2]. House crows eat crops and damage
orchards [6], [7]; disturb tourists and local citizens with
their loud calls, as well as their heavy defecation and
aggressive attacks when attempting to steal food [6];
transmit pathogens, which affect people and domestic
animals [8], [9] and also pose a bird strike risk to aero
planes [2]. The crows are also responsible for the
Manuscript received May 10, 2014; revised December 10, 2014.
reduction or severe depletion of small reptiles and
amphibians, 1. birds and mammals, insects, fish and
domestic animals [4] disturbances. However, in the areas
that are newly colonized by this bird species, the impact
is believed to be high. In most of the affected countries,
no control projects against the house crow are undertaken. The success of the House crow is considered to be the
cause of the decline of some other bird species inhabiting
Ismailia and surrounding areas, such as Lesser kestrel,
Hooded crow, Brown-necked raven, Fan-tailed raven,
Hoopoe, laughing dove, collard dove, Robin, White
throat kingfisher, pied avocet, white and yellow wagtail.
The species is also causing harassment to visitors at some
of the hotels along Fayed beaches, and reportedly may
cause economic losses by inflicting damage to main crops
and poultry (Atef, personnel communication). In
Addition, the species has been reported to be a possible
carrier and transmitter of diseases, such as cholera,
dysentery and West Nile Virus [8]. It is virtually
impossible to monitor the success of control or
eradication programs without any basic data on the
current distribution and numbers of the house crow. At
Present, no reliable data available on the number of crows
in and around Ismailia Governorate. As recommended,
there is need for more research into the House crow. The
aims of the present study were to: (1) to count the total
number of crows that roost on Ismailia and surrounding
cities & localities. (2) to assess which areas these crows
mainly come from., (3) to study the group size and
behavior at Study areas, and (4) to study the impact of
house crow on socio-economic and agriculture,
biodiversity and environment and Human health and
general amenity.
II. METHODOLOGY
A. Study Site: Ismailia
Ismailia is the East Gate of Egypt to pass to the Arab
countries and other Asian countries, it is in the middle of
Suez Canal territory which includes Canal It is Ismailia is
situated at 30.61° North latitude, 32.28° East longitude
and 14 meters elevation above the sea level.
Journal of Life Sciences and Technologies Vol. 2, No. 2, December 2014
2014 Engineering and Technology Publishing 86doi: 10.12720/jolst.2.2.86-89
B. Bird (Corvidae) Species
Four species of corvids were considered the most
common species in Ismailia Governorate, Brown necked
ravens (Corvus ruficollis), Fan-tailed Raven (Corvus
rhipidurus), Hooded Crow (Corvus cornix) and House
Crow (Corvus splendens) are in huge amounts attracted.
The birds are very aggressive and showed to be a serious
pest. They spread germs and diseases for human health
and food production. Therefore, the birds need to be
controlled.
C. Bird Census
Birds monitoring patterns in Ismailia and surrounding
urban and rural areas (Abu souir and El maniaf,) were
carried out throughout study. Data were collected and
analyzed in a comprehensive database. On August 2013,
from 4.30 p.m. to 7.00 p.m., counts were made of all
crows sitting at Ismailia Governorate and surrounding
urban and rural localities, where daily activity patterns
increase. Counts were made by observers stationed
strategically at four observation points around the
Governorate the crows were counted per intervals of 15
minutes. Since most birds arrived in small to larger
groups, the number of birds present in each group was
recorded (although sometimes it was difficult to tell what
was one group). Counting was sometimes aided by the
use of binoculars, but most counts were performed by
naked eye. The position of the different counting stations
was chosen as to minimize the risk of double counts.
III. RESULTS
A. Current Bird Populations at Ismailia Governorate
and Other Locations
Table I and Fig. 1 and Fig. 2 summarize the results of
the counts. In total, we counted 10909 House Crows
roosting and flying across Ismailia Governorate and the
other five (5) observation sites between 16.30 and 19.00
p.m. Besides House Crows, only5 Hooded Crows and (3)
Brown –necked raven and 1 Brown-necked raven were
observed during were located at Old Suez Canal
University, whereas 1772 birds from Ismailia city
(16.24%), whereas in Suez Canal University old building
was 7443 (68%). It shows the distribution of the House
crow in the 5 study locations, with the peak of fling was
between 17.45 and 18.00 p.m.. Data for each individual
counting sites yielded similar temporal patterns and from
this figure it becomes clear that the counting period
covered nearly all the activities of House crow and that
the number of birds which counted prior to 16.30 pm and
after 19.00 (when it became too dark to count anything) is
likely to be insignificant. Prior to roosting, the birds
appeared to be in groups over trees, roofs of Suez Canal
University (Old and new buildings) and other high
buildings in Ismailia, and electrically poles & wires.
After their aggregations and had reached a certain size,
they started crossing to other areas or buildings as a large
groups. The size of each groups varies considerably, but
usually ranged from 4-10 birds during crossing areas and
increase up to 20-30 birds during roosting (go nesting).
This was most noticeable during peak period of roosting,
that is between 17.45 and 18.30 p.m.
Figure 1. Total number of house crow in thousands counted in all locations for each time interval in all locations.
Figure 2. Total number of House crow counted in five study locations
during time interval.
TABLE I. RESULTS OF COUNTS OF HOUSE CROW CROSSING AND ROOSTING IN ISMAILIA GOVERNORATE, SUEZ CANAL UNIVERSITY OLD BUILDING
AND SURROUNDING URBAN, RURAL AND LAKES AT THE 5 OBSERVATION POINTS DURING THE DIFFERENT TIME INTERVAL (DATE 1AGUST 2013 TIME: )
Time Interval Ismailia Abu Souwair Almanaif Suez Canal University Old Building Suez Canal Lakes Total
16.30-16.45 166 50 28 280 90 614
16.45-17.00 180 33 44 310 77 644
17.00-17.15 205 45 60 955 45 1210
17.15-17.30 153 33 75 1180 69 1510
17.30-17.45 244 66 33 1690 91 2124
17.45-18.00 190 37 60 1010 82 1329
18.00-18.15 99 88 55 930 65 1237
18.15-18.30 220 58 41 450 44 813
18.30-18.45 177 45 59 440 67 788
18.45-19.00 138 64 67 198 73 640
Total 1772 519 522 7443 642 10909
Journal of Life Sciences and Technologies Vol. 2, No. 2, December 2014
2014 Engineering and Technology Publishing 87
B. Ecological Impacts
The results show that, It seems reasonable to suggest
that the impacts of Indian house crows in Ismailia
Governorate would be comparable to those experienced
elsewhere. It was observed at Fishing Point and fish
farms, which is about 30 km north Timsah and Bitter
lakes, Ismailia. (Subsequent searching failed to detect the
bird. These impacts are like to be in the following areas:
Agriculture. The house crows are considered
significant pests throughout their range in Ismailia
Governorate, mainly due to their high abundance
in villages, towns and cities, where they create
considerable noise and are perceived as a risk to
human health and their crops. They have damaged
fruit crops (including mango, guava, dates, fig,
tomato, cucumber, grape, Cantaloupe, strawberry,
watermelon, and stone fruits e,g, peach),There is
also risk of damage to grain crops (,including
wheat, green beans, Cabbage, barley, peanuts, rice,
olives. especially in Abou Sowier and AlManif
cities, Serapium and other rural areas as well as
Timsah and Bitter lakes) they are considered a
serious threat to nesting seabirds.
Biodiversity & Environment. There is likely to be
reduced abundance of certain bird species,
especially urban species, because of predation of
eggs and chicks and competition for food. Are
likely to face strong competition with other bird
species identified in Ismailia Governorate.
Human health. There is significant community
concern about the risk of House crow bird-
transmitted diseases (West Nile virus).
IV. DISCUSSION
This study provides highlight and detailed record of
numbers of house crow in Ismailia Governorate (Suez
canal lakes and beaches, old Suez canal university) and
around (Abu Souweir and Al Manaif cities) that was
counted (10909 birds) does not include other cities, and
other birds move and form gregarious rooting to other
side of Suez canal channel (Al kantara) which remains
yet to be studied. Preliminary monitoring indicate that
most and main of the House crow roosting sit was the old
Suez Canal University, around slaughter house, hospitals,
railway station and gardens and Suez Canal beaches
where a strong and high trees were located and the crow
aggregate in groups (6-10 birds) then fly to other building
and cities around Ismailia. Indian house crows are
considered significant pests throughout their range,
mainly due to their high abundance in villages, towns and
cities, where they create considerable noise and are
perceived as a risk to human health [10]. There have
damaged fruit crops (including mango, guava, dates, fig,
tomato, cucumber, grape, Cantaloupe, strawberry,
watermelon, and stone fruits e,g, peach), especially in
Abou Sowier and Al Manif cities, but potentially in other
rural areas as well. There is also risk of damage to grain
crops (, including wheat, green beans, barley, peanuts,
rice, olives, Egg plant, green pepper, potatoes, cotton,
sesame, Maize, corn and sunflowers. Some losses of
poultry, newborn calves and newborn goats are possible.
[6] and [10]; reported that they have damaged fruit trees
(e.g. mango, guava, pawpaw, fig, apple, pear, grape and
stone fruits) and have raided grain crops, including wheat,
corn and sunflowers [11],[12]. House crows also reported
in Ismailia Governorate to kill poultry, pigeon, destroy
other bird nests, the same as reported by [12].
V. CONCLUSION
Bird monitoring suggests Indian house crows are well-
suited to most Ismailia governorate and surrounding
urban and rural areas. Since Indian house crows are well
established in Ismailia Governorate, there is an
opportunity to becoming a major pest. Successful risk
management will rely on detection and effective public
awareness. In particular, keen birdwatchers can play a
vital role in detection, as they can differentiate house
crows from native crows and ravens.
ACKNOWLEDGEMENTS
The authors would like to thank all of the local peoples
and University of Suez Canal students (volunteers)
involved in house crow census, regardless of the capacity
in which they helped. We are indebted to all local
residents at census cities for their encourage and helping
me to prepare this paper to identify how big the impacts
and census of the house crow.
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Journal of Life Sciences and Technologies Vol. 2, No. 2, December 2014
2014 Engineering and Technology Publishing 88
Kamel A. M., Head of Wildlife Management and Zoo Medicine Department, Faculty of Veterinary Medicine, Suez Canal University,
Ismailia, Egypt
Journal of Life Sciences and Technologies Vol. 2, No. 2, December 2014
2014 Engineering and Technology Publishing 89