First Confirmed Record for the Lepomis gibbosus ( L . , 1758 ) in The Lower Sakarya River Basin ( Turkey )

This paper is the first reference of pumpkinseed (Lepomis gibbosus) in the lower Sakarya River basin (Turkey). The data were obtained from samplings carried out between April 2017 and July 2017. L. gibbosus is currently found in only two regions of Turkey, its introduced range is expanding rapidly, and for this reason it is important to monitor the impacts of this introduced species on natural ecosystems.


Introduction
Lepomis gibbosus has a high and laterally compressed body shape.The maximum size is up to 40 cm of total length (TL) in its native area (Page and Burr 1991), but is smaller in European water bodies (Copp et al. 2004).Unique colouration helps L. gibbosus stand out from other members of the sunfish family.The breast and underside of pumpkinseeds are orange to red-orange, while the back and sides are brown to olive.On some individuals, speckles of orange, yellow, blue and emerald may be found on the sides, back, anal and caudal fins.L. gibbosus have seven to eight irregular vertical bands on their sides.Radiating back from the snout and over the opercula are several wavy stripes (Jordan et al. 2009).
The native range of L. gibbosus is restricted to North America.The species was originally found from New Brunswick down the Atlantic seaboard as far as northeastern Georgia.The species also occurred west of the Appalachian Mountains from southern Quebec to southern Ohio, west to northern Missouri, and north through eastern South Dakota to eastern Manitoba, including western Ontario (Scott and Crossman 1973).

Material and Methods
The Sakarya River Basin is Turkey's third largest river basin, with a total area of 58.160 km 2 .It is 824 km long and its drainage basin covers 7.5% of Turkey's acreage.Its average flow rate is about 190 m 3 per second.The water temperature changes between 7 to 24 °C throughout the year.The river basin is divided into three regions named Lower, Mid and Upper Basin (Sengorur and Isa 2001).
This study was conducted in three separate regions of Lower Sakarya Basin (Figure 1  Samples of L. gibbosus (Figure 2) were collected with gill-nets (22-36 mm mesh size) and electroshock (SAMUS1000) in Lower Sakarya River between April 2017 and July 2017.
Overall, 26 samples from L. gibbosus was examined in the lower Sakarya River in Turkey.Samples brought to laboratory and were measured by boards.Total length (TL) was recorded to the nearest centimetre (0.1 cm), and bodyweight (W) was recorded to the nearest gram (0.01 g).

Result and Discussion
In this study, total length and weights were found that 8.7 (min) -14.7 (max) cm and 13.53 (min) -75.74 (max) g respectively for L. gibbosus (Table 1).
According to local fisherman, this fish started to be seen in the Sakarya river since 2016.L. gibbosus has been reported mainly for Mediterranean countries, where their diet has included endemic mollusc subspecies (García-Berthou and Moreno-Amich 2000) and fish eggs (García de Jalón et al. 1993).Although L. gibbosus is currently found in only two geographic regions of Turkey (Ozcan 2007), its introduced range is expanding rapidly.The severe ecological and economic damage by L. gibbosus in the Sakarya river must alert the authorities to monitor the effects of this introduced species on natural ecosystems.Contact and communication with local stakeholders (citizen scientists, fisherman, local authorities) may provide an effective mechanism for the early detection of invasive species in a new area.Efforts should also be made to build coherent databases to track progress in the region.

Table 1 .
Minimum-maximum and mean length and weight of the L. gibbosus collected in Sakarya River, Turkey.