Crucian carp invasion of Turkish & Iraqi inland waters The crucian carp, a small hardy freshwater fish native to Europe and Asia, was unintentionally introduced to inland waters in Turkey and Iraq in the 2000s. It has since become the dominant fish species in some aquatic systems, comprising up to 70% of fish in some Iraqi waters. The crucian carp tolerates a wide range of habitats and water conditions, and strongly competes with native fish for food and space. Its rapid population growth and predatory impact on plankton and other fish species pose a serious threat to the biodiversity of native Turkish and Iraqi inland fisheries. Management efforts are needed to control the spread and impact of this invasive cruc

1. Crucian Carp invasion
of Turkish & Iraqi
inland waters
Firas Abdul Malik
Fish Biologist
1

2. Introduction:
Crucian carp (Carassius carassius) (Linnaeus, 1758) the most
freshwater fish that inhabits in every place of Japan, China and most of
Europe including Russia (Copp & Sayer, 2010). The Crucian Carp is the
smallest of the Carp family It is easily distinguished from a small common
carp by the absence of barbels. They live in lakes or stagnant areas of
rivers. This fish small head and mouth and an up-turned lower lip. It tends to
be rusty-bronze in color with a gold-orange colored belly (Jasim,2009). Basic
cyprinid characteristics include no teeth on the jaws, a single dorsal fin,
pelvic fins in an abdominal position, pectoral fins low on the side, and no
adipose fin. (Aydin, et al., 2011 & Pamela, et al., 2006). Crucian carp can
grow to about (20-30) cm maximum length, they can live up to 10 years,
although older-living individuals have been known (Taran, et al., 2000).
Crucian carp prefer small, nutrient-rich ponds and lakes. They are very hardy
fish: has an amazing ability to survive for months with almost no oxygen.
This is an adaption to allow survival in ponds that are frozen over and
covered with snow - survive water temperatures up to (38oC) (Yilmaz, et al.,
2004). and can live in acidic waters where the pH can be as low as 4.
Crucian carp are also very tolerant of pollution, especially organic types
(Radi,2012). 2

3. Kingdom: Animalia
Phylum: Chordata
Subphylum: Vertebrata
Class: Actinopterygii
Order: Cypriniformes
Family: Cyprinidae
Genus: Carassius
Species: carassius
Local name: Shokhatt
3
Classification:

4. External Anatomy:
Figure (1): Crucian carp anatomy.
Source: Jasim,(2009).
4

5. Figure (2): A. Crucian Vs. Gold fish.
5
Fish Distinguish:
Figure (3): A. Crucian Vs. common carp.
Source: (Radi,2012).

6. 6
Video (1): Crucian carp - YouTube.

7. Distribution:
Source: (Pamela, et al., 2006).
Figure (4): Native distribution of Crucian carp (in dark blue). 7

8. Main producer countries :
Source: (Freyhof & Kottelat, 2008).
Figure (5): Crucian carp inhabits lakes, rivers and reservoirs
in various countries in Asia and Europe. (in orange).
8

9. Figure (6): Global aquaculture production of Crucian carp. 9
Source: (Freyhof & Kottelat, 2008).

10. Crucian carp in Turkey:
C. carassius is native to Turkey. Species of the genus
Carassius were transported to numerous inland water
bodies throughout Turkey perhaps because of the physical
similarity of the species to the native common carp
(Cyprinus carpio Linnaeus, 1758). As a result of mis-
identification, the expansion of species were not noticed.
These species are now common in natural habitats, altered
waters, park and garden ponds in various parts of Turkey.
(Innal,2011) Introduction of fish species in Turkey, like
elsewhere in the world, has had both positive and negative
implications. But the impact of most introductions of fishes is
still unknown. Abundance and distribution of Carassius
species in Turkey continuous to increase steadily, and are
now considered a threat factor for native fish species.
10

11. Ecosystem typeCityLocalities
Reservoir‐PondBalıkesirİkizcetepeler
Reservoir‐Pond & Natural LakeIspartaKaracaören I & Kovada
Natural LakeBurdurKarataş
Stream‐CreekKarsKars
Reservoir‐PondKütahyaKayaboğazı
Reservoir‐Pond & RiverAntalyaKöprüçay Kepez I
Natural LakeAdapazarıKüçük Akgöl
Natural LakeManisaMarmara
Reservoir‐PondSinopMuhsinli & Nisa
Reservoir‐PondMuğlaMumcular
11
Source: (Innal,2011)
Table (1): Distribution of C. carassius in the
inland waters of Turkey:

12. Table (1): Distribution of C. carassius in the
inland waters of Turkey:
Ecosystem typeCityLocalities
Natural LakeVanNazik
LagoonEdirnePamuklu
Natural LakeAdapazarıSapanca
Reservoir‐PondAfyonSelevir
Natural LakeAdapazarıTaşkısığı
Natural LakeBursaUluabat
Reservoir‐PondHatayYarseli
Reservoir‐PondKütahyaYedigölller
Natural LakeBoluYeniçağa
Stream‐CreekKayseriZamantı
12
Source: (Innal,2011)

13. Table (2): Environmental characteristics of
Crucian carp:
ReferenceCharacteristics
5,18Adapt to natural waters
4Adapt to altered waters
4,5,18Adapt to various physical and chemical factors
5High reproductive potential
3,4,5,18Dominancy
5Invasive tendency
3, 5,19Harmful competition with native species
5Hybridization with native species
2,12Host or a intermediate host of parasites
5Interspecific competition
References included in Table (2): , [2] Aydogdu, (2006); [3] Balik & Ustaoglu,
(2006); [4] Becer et al., (1998); [5] Cetinkaya et al., (1999); [12] Koyun, (2001);
[18] Taran et al., (2000); [19] Yilmaz, (2004).
13

14. Crucian carp in Iraq:
C. carassius is one of the scavengers fish. It can eat
anything in the aquatic body like brushwood. This fish
maturate in less than one year while other local fish
maturation extend four years like shabout & Gattan or two
year like Bunni. (Radi, 2012). Inhabit and sweeping of
environment affecting on the growth and life of original fishes.
Because all local Iraqi fish don't tolerate turbidity because this
type is bottom-feeder besides the ability of crucian to
reproduce with other cyprinids type making sterile
individuals in some cases (Fahd, 2012). So, it is important to
obtain the balanced between this fish and other original fishes
by controlling the release of this fish from Turkish dams and
other aquatic bodies in order not to invade these bodies by
foreign type with decreasing the main fish types.(Mohamed et
al., 2006). 14

15. No. Fish type %
1. Crucian Carp 70%
2. Common carp 15%
3. Shabout 4%
4. Toueni 3%
5. Gattan 3%
6. Bizz 2%
7. Catfish 2%
8. Beyah 1%
Table (3): The ratio of crucian carp against the
native Iraqi fishes.
Source: Radi,(2012)
15
Source: EPIB & Al-Jader, (2013).

16. Figure (7): Length groups of the crucian carp. 16
Crucian carp is fishing all the year. Length group (10-20) cm most
dominant group which contain (78.6%) from total fishing.
Source: Mohamed et al., (2006)

17. Country Lmax (cm) Wmax (Kg)
Iraq 25.7 2.6
Turkey 23 2.1
Finland 64 6.4
Poland 41 3.9
Netherlands 43 4.2
Denmark 40 3.2
China 14.8 1.4
Nepal 17.5 1.7
Sources: Fahd,(2012), Onsoy et al.,(2011) & Aydin et al.,(2007)
17
Source: EPIB & Al-Jader, (2013).
Table (4): Length and weight of Crucian carp by
Countries.

18. Food Ingredients:
Table (5) : Main food
for crucian carp
juveniles & adults.
Age stage Diet
Juvenile Zooplankton
Adults mollusks, worms,
various insects,
crustaceans and some
plant material
Notes: opportunistic feeders, utilize
any available food source, sucking
bottom sediments while feeding.
18
Video (2): Showing the
Crucian carp Feeding
Frenzy - YouTube.

19. 19
Video (3): An Interesting Hybrid, crucian carp with
fantail! – YouTube.

20. 1. This fish consider chieftain of Tigris & Euphrates fishes.
2. The Crucian carp was introduced to Iraq by unintentional release
from Turkish dams throw 2005.
3. Tolerant and hardy fish that thrive in a wide variety of aquatic
habitats.
4. Strongly compete with the young of most cyprinid fish species for
food and space.
5. Crucian carp is known as one of the most hazardous fish species
for native fish communities.
6. Currently the largest (3/4 of all fish production is crucian carp).
7. It appears to occupy an unexpected ecological niche or even lead
to unexpected changes in the behavior of native species.
8. Predate heavily on phytoplankton and zooplankton.
9. Appear to be a serious competitor of native fish species.
10. Population density of the Carassius species have increased
rapidly in the inland waters of Turkey & Iraq , and now it is the
dominant fish species of some aquatic systems.
20
Conclusions:

21. References:
Aydin, H.; , Gaygusuz, O.; Tarkan, A.; Top, O.; Ciğdem G.& Gaygusuz, C. (2011).
Invasion of freshwater bodies in the Marmara region (northwestern Turkey) by
nonnative gibel carp, Carassius gibelio (Bloch, 1782). Turk J Zool.(6)-35:c
TUBİTAK.doi:10.3906/zoo-1007-31.pdf(829-836)pp.
Aydogdu, A. (2006). Variations in the infections of two Monogenean species parasitizing
the gills of the crucian carp (Carassius carassius), in relation to water temperature
over a period of one year in Gölbasi Dam Lake, Bursa, Turkey. Bulletin of European
Association of Fish Pathologists 26(3):112-118
Balik, S.; Ustaoglu, M. (2006). Fish introducing studies in Lakes, Ponds and Reservoirs
of Turkey and their results (In Turkish with English Summary). I. Symposium on
Management of Reservoirs and Fish Stocking, MARA, Mediterranean Fisheries,
Production and Education Institute, pp: 1‐10.
Becer ,Z. A.; Kır, I. & Cubuk, H. (1998). Some reproductive charecteristics of the
Carassius carassius L., 1758 (Isparta‐ Burdur) in the Karacaören I Dam Lake (In
Turkish with English Summary). XIV. Ulusal Biyoloji Kongresi, Samsun, pp: 126‐138.
Cetinkaya, O.; Elp, M. & Sen, F. (1999). Studies on crucian carp (Carassius carassius
L.) introduced into Lake Nazik (Ahlat‐ Bitlis, Turkey) (In Turkish with English
Summary). X. Ulusal Su Urunleri Sempozyumu, Adana, pp: 814‐825.
Copp, G.H. and Sayer, C.D. (2010). Norfolk Biodiversity Action Plan – Local species
action plan for crucian carp (Carassius carassius). Norfolk Biodiversity Partnership
Reference: LS/3. Centre for Environment, Fisheries and Aquaculture Science-
Lowestoft. 9 pp.
21

22. References:
EPIB(Environmental Protection & Improvement Board) & Al-Jader, Firas A. M.
(2013). Preliminary Survey of fish species in Duhok Governorate Borders.
Fahd, Kamel K. (2012). Some aspects of ecological and biological in the crucian carp
Carassius carassius in Al-Baddah Dam,Thi-Qar Iraq. Thi- Qar J.Agric. Res., 1 ( 1 )
2012.11p.
Freyhof, J. & Kottelat, M. (2008). Carassius carassius. In: IUCN 2012. IUCN Red List of
Threatened Species. Version 2012.2. <www.iucnredlist.org>. Downloaded on 24
April 2013.
Innal, D. (2011). Distribution and impacts of Carassius species (Cyprinidae) in Turkey: a
review. ISSN 1989‐8649 Manag. Biolog. Invasions, 2011, 2.
www.managementofbiologicalinvasions.net. Department of Biology, Mehmet Akif
Ersoy University, 15100, Burdur, Turkey. Copyrights 2011owned by The Authors
innald@yahoo.com.57-68pp.
Jasim, Ali, A.(2009). Fecundity, sex ratio and age at sexual maturity of crucian carp
,carassius carassius l.,1758 in tigris river,mosul-iraq. Fish & Mar.Res.Dept./College of
Agriculture /University of Basrah. Mesopotamia J. of Agric. (ISSN 1815-316X) Vol. (
37) No. ( 2) 2009.pdf:8p.
Koyun, M. (2001). The helminthofauna of some fishes in Enne Dam Lake (In Turkish
with English Summary). Phd Thesis, Uludag University, 119 pp.
Lorenzoni, M.; Corboli, M.; Ghetti, L.; Pedicillo, G. and Carosi, A. (2007). Growth and
reproduction of Carassius : a case study from Italy. Gherardi: Biological Invaders in 22

23. Mohamed, A. R. M., Al-Noor, S. S. and Faris, R. A. K.(2006). Analytical Study Of The
Fisheries In The Lower Reaches Of The Tigris River, North Qurna, Basrah, Iraq.
Department of Fisheries And Marine Resources, Agriculture College, Basrah
University, Iraq & Basrah Agriculture Directorate, Agriculture Ministry, Iraq. Iraq J.
Aqua (2006) 1, 57-73.
Onsoy, B.; Tarkan, A.S.; Filiz, H. & Bilge, G.; (2011). Determination of the best length
measurement of fish, North‐western Journal of Zoology 7 (1): on first.
Pamela, J.; Schofield, J.; Williams, D.; Leo, G.; Nico, P. F., and Matthew, R. T,
(2005). Foreign Nonindigenous Carps and Minnows (Cyprinidae) in the United States
- A Guide to their Identification, Distribution, and Biology. Southeast Ecological
Science Center.U.S. Department of the Interior |U.S. Geological Survey URL:http ://
fl. Biology .usgs. Gov / Carp_ID /index .html
Page Contact Information: Buck Albert - Web Administrator.
Radi, Enas M. (2012). Project of developing fish resources in Iraq. © University of
Babylon 2010-2011. All rights reserved. Part of :UOB-IT Operations.
Taran, H.; Kucuk, F.; Becer, Z.; (2000). The investigation of population structure and
some reproduction charecters of crucian carp (Carassius carassius L., 1758) in Lake
Egirdir (In Turkish with English Summary). Ulusal Ogrenci Su Urunleri Sempozyumu,
pp: 11.
Yilmaz, F. (2004). Physico‐chemical features of Mumcular Dam Lake (Muğla‐Bodrum)
(In Turkish with English Summary). Ekoloji 13 (50): 10‐17.
References:
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