Esenias and Dias Scientific Conference and 10th Esenias Workshop, 7 - 09 December 2021
Delice
River is the one of our long stream is decharging to Kızılırmak River. It has
been appeared with the small tributaries from the South-east of Yozgat province.
the improtant tributaries of Delice River are Kanak, Karasu, Koyunluyusufözü, Killiközü,
Budaközü and etc. In particular, with the merging of Kanak and Karasu Streams
in the district of Sefaatli, it takes the name of Delice River.
Delice
River shows flow characteristics between Çankırı, Yozgat, Kırşehir and
Kırıkkale provinces. Its surface area is approximately 78.189 km², its annual
water volume is 6 billion m³, and its average flow rate is 30,352 m3/sec.
In
this study, 22 stations were determined on the Delice River and its tributaries
via Field observation. Seasonally, fish samples were taken from these stations
between March 2019 and February 2020. For the fish catching back type
electrofisher device and various meshes were used.
It
is identified that 2 invasive species belonging to 2 families which are Poeciliidae
and Cyprinidae. Gambusia holbrooki is
used in mosquito control. It is considered like the rapidly spreading and
invasive species in Turkey's inland waters.
G. holbrooki individuals had been caught in only one station with a low
population in next to Kızılırmak and Delice River joint point. G. holbrooki entered the Delice River
lately and there is no information about routes of the entry. Although, There
is only one record from Kızılırmak River, not any record from Delice River. It
is very important to be the first record from Delice River. It is thought that
it has not spread over a wide area in the Delice River yet, but it may have
negative effects on other species due to the species' invasiveness and rapid
spread.
Pseudorasbora parva
individuals, had been caught in 5 stations which were far form each other with
low population. It has been observed that it can be found in areas with
different physicochemical parameters indicates its high environmental tolerance
and adaptability. It has been understood that P. parva individuals generally live in the same habitats with
Cyprinidae species. It has been observed that the individuals have not yet
spread in the majority of the stations in the Delice River and their population
density is very low compared to other species. In addition, P. parva records has been reported by
researchers from Kızılırmak River and Gelingüllü Dam Lake.
It
is thought that invasive species do not pose a significant threat in Delice
River yet, but when compared with the other water systems, they will cause
habitat shrinkage for other species if they spread in this water system.
However, in fact it has been prooved that Delice River has good conditions to
these invasive individuals for growing new populations. In the near future, it
can be tought that they can easily spread in Delice River and its tributaries.