ICHTHYOCENOSIS OF INTERNATIONAL WETLANDS
OF ALMA–GOL, ADJI–GOL AND ALA–GOL,
NORTH OF IRAN; IMPLICATIONS OF ALIEN FISH SPECIES
FOR CONSERVATION AND MANAGEMENT OF WETLANDS
R. Patimar*, B. H. Kiabi**
*Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran,
**ShahidBeheshtyUniversity, Teharn, Iran, E-mail: email@example.com
Key words: Ichthyocenosis, alien species, wetland, Iran
Р. Патимар*, Б. Х. Киаби**
*Джорданский Университет сельского хозяйства и природных ресурсов, Джордан, Иран,
**Университет Шахид Бехешти, Тегеран, Иран, E-mail: firstname.lastname@example.org
Ключевые слова: ихтиоценоз, интродуцированные виды, водно-болотные угодья, Иран
The introduction of exotic fishes to inland aquatic ecosystems is often associated with decline in native species to those water. Biologists concerned that many species are being lost through habitat disturbance and destruction and many exotic species introduced in many situations, where they appear to have competitive advantage over native taxa. In relation with this case, a study was conducted to explore and understand ecological aspects of alien species in the international wetlands of Golestan province during September 2000 until August 2002. The wetlands represent a group of three small and rather isolated brackish and freshwater lakes (Scott, 1995).
The results revealed that out of 10 sampled fish species, belonging to 3 families, 5 species including Sharp belly Hemiculter leucisculus, Silver Crucian carp Carassius auratus, Topmouth gudgeon Pseudorasbora parva, Mosquito fish Gambusia holbrooki, Common carp Cyprinus carpio were alien. At regional level, Alma–Gol and Ala–Gol contained 90,9 % and 82,2 % (of total frequency of fishes) exotic species respectively. Two alien species H. leucisculus and C. auratus comprised 58,0 % and 77,6 % of overall fish frequencies, were far the most abundant species in Alma–Gol and Ala–Gol accordingly. H. leucisculus is an exotic fish for the Caspian basin and inland water of Iran as well. Concerning the H. leucisculus, it seems that the situation is rather ambiguous in this area, as Borisova (1972) blamed this species for the partial displacement of native species. One of the more frequent species in the wetlands is C. auratus. It is well known as aggressive species in inland waters, which counted for decrease of native fish stocks (Kukuradze and Mariash, 1975).
It is believed that non-indigenous species threaten native biodiversity, ecosystem function and taxa health (Meyers et al., 2000). Recent studies suggest that the success and spread of an invasive alien species in a natural system depends on different factors like life history, their ability to respond to natural selection, demographic traits and interspecies interactions (Lee, 2000; Mayle et al., 1986).
Two mentioned exotic species had high frequency in the wetlands that might be a serious competitor for food and space with the juvenile and adults of native fish and also could be effect the native fish taxa, as decreased frequency of native species implies these concepts. Although, the case study presented here had a wetland focus, our assertion is that native fish taxa in other region of south Caspian Sea may be more at risk, as Abdoli (1999) and Kiabi et al. (1999) cited many exotic fish species inhabiting these areas. Therefore more in depth works needed to determine whether measure to control alien species reproduction and their distribution.
Zoocenosis — 2005
Біорізноманіття та роль зооценозу в природних і антропогенних екосистемах: Матеріали ІІІ Міжнародної наукової конференції. – Д.: Вид-во ДНУ, 2005. – С. 87-88.