Yuksel, Fahrettin; Cilbiz, Mehmet; Demirol, Ferhat; Capkin, Kadir; Bektas, Zubeyde Hanoi; Gunduz, Fatih

Narrow-clawed crayfish (Astacus leptodactylus Eschscholtz, 1823) is native species to Turkey and the most important shellfish because of its commercial value and ecological role in ecosystem. The knowledge on bio-ecological features of narrow-clawed crayfish is limited. In this study, total length (TL), carapace length (CL), carapace width (CW), abdomen length (AL), abdomen width (AW), chela length (ChL) and chela width (ChW) of narrow-clawed crayfish were compared in two different habitats (Egirdir Lake and Keban Dam Lake). According to linear regression analysis, the highest relation was between TL and AL (R2=0.987) of the female in Egirdir Lake and the weakest relationship was between AW and ChL (R2=0.084) in Keban Dam Lake. Overall, the biometric features of A. leptodactylus populations in Egirdir Lake and Keban Dam Lake were different and these differences were significant in mid-length groups. These findings clearly demonstrated the impact of commercial catching on the length distribution of the crayfish stocks.

AtıfScopus5

İncele

Yuksel, Fahrettin; Gunduz, Fatih; Demirol, Ferhat

A study was conducted to determine the selectivity of monofilament gillnets with mesh sizes of 50, 60, and 70 mm that are used in Keban Dam Lake for fishing Luciobarbus esocinus (Heckel, 1843). During the study, a total of 394 L. esocinus were caught. Selectivity parameters were estimated using the indirect estimation method developed by Holt (1963). Optimum selection lengths for L. esocinus were calculated to be 36.61, 43.94 and 51.26 cm for gillnets with mesh sizes of 50, 60, and 70 mm, respectively. Common selectivity factor was estimated to be 7.32, with standard deviation 4.58. Length at first maturity of female L. esocinus (50 cm) was compared to the optimum selection lengths of gillnets with mesh sizes of 50, 60, and 70 mm. Results indicate that gillnets with mesh size of 70 mm would be appropriate for harvesting L. esocinus in the Keban Dam Lake, as the optimum selection length (51.26 cm) is greater than length at first maturity.

AtıfWoS4

İncele

Coban, Mehmet Zulfu; Yuksel, Fahrettin

This study was aimed to investigate the some growth properties of Acanthobrama marmid Heckel, 1843 population in Uzuncayir Dam Lake (Tunceli/Turkey) between May 2011 to September 2012. A total of 604 A. marmid samples (340 males and 264 females) were caught from Uzimcayir Darn Lake; the age composition of the specimens ranged between 1-9 years. The overall sex ratio (females/males) was 1:0.78. Total lengths of specimens ranged from 8.80-27.80 cm and weights ranged from 6.20-182.00 g. The von Bertalanffy growth parameters were L.-0= 28.25 cm, K = 0.26 year and to = -0.90 year for males andLc, = 28.49 cm, K = 0.23 year' and t(0) = -1.24 year for females. The length-weight relationship was found as W = 0.009 /T1,39 in males and W = 0.012x in females. The growth perforrnance index (0') values of males, females and all samples were 2.317, 2.271 and 2.301, respectively. The condition factor values varied between 0.61-1.30 for entire population.

AtıfWoS1

İncele

Yuksel, Fahrettin; Celayir, Yasin

In this research it has been targeted to estimate fishable stocks of Karakaya Dam Lake (in Turkey) by using fishing with gillnets method that had been suggested as an alternative method for estimating fish stocks. Productivity per hectare in the dam lake and the amount of fishable stocks has been calculated to be 13.67 kg ha(-1) and 312.005 kg year(-1), respectively. Fishable stocks have also been analyzed with respect to fish species. According to this, Capoeta sp. is estimated to be 184.107 kg year(-1) (8.06 kg ha(-1)), Cyprinus carpi carpio is estimated to be 56.353 kg year(-1) (2.47 kg ha(-1)), Barbus sp. is estimated to be 40.580 kg year(-1) (1.78 kg ha(-1)), Squalius cephalus is estimated to be 30.455 kg year(-1) (1.34 kg ha(-1)) and Onchorincus mykiss is estimated to be 510 kg year(-1) (0.02 kg ha(-1)).

AtıfWoS3

İncele

Pala, Murat; Yuksel, Fahrettin

This study was conducted in Keban dam lake Cemisgezek region during 2000-2001 fishing season. In the study, the effect of mesh size on catching efficiency was analyzed. For this reason, a total length of 800 m gillnet was used, particularly two monofilament gillnets with 50, 60, 70 and 90 mm mesh size, each being 100 m long. During the research, Cyprinus carpio and Squalius cephalus was indicated with own species names, which are caught on 22 hunting attempts. Barbus esocinus, Barbus capito pectoralis and Barbus mystaceus species regarded as Barbus sp., Capoeta trutta and Capoeta umbla species regarded as Capoeta sp. The most frequently caught species in the research were Capoeta sp. on 50 and 70 mm mesh sizes, Barbus sp. on 60 mm mesh size and Cyprinus carpi on 90 mm mesh size. The species that is least frequently fished on all gillnets was Squalius cephalus. When the catch per unit effort was analyzed taking into account all species, it was observed that with 83.1 g m(-1) catch per unit effort, 60 mm gillnet was more efficient than all other gillnets. This gillnet was followed by 79.9, 41.0 and 31.8 g m(-1) catch per unit efforts for 50, 70 and 90 mm mesh sizes, respectively. In conclusion, it has been found out that in the study region, gillnets with 50 and 60 mm mesh sizes are more effective than gillnets with 70 and 90 mm mesh sizes.

AtıfWoS1

İncele