Age, growth and feeding of the common stingray (Dasyatis pastinaca, L., 1758) in the Cilician coastal basin, northeastern Mediterranean Sea

Abstract

Growth and feeding of stingray (Dasyatis pastinaca) were studied using 346 specimens from the Cilician Basin coastal area (northeastern Mediterranean). Age classes between 0 to XII were found. The total length of all specimens ranged from 14.6 to 100.9 cm, and total weight was between 22.5 and 6800 g. Total length (TL)-weight (W) and disc width (DW)-weight (W) relationships were W = 0.0033*L 3.1429 and W = 0.0039*DW 3.4914 , respectively. The age data, derived from central readings, were used to estimate the von Bertalanffy length and weight growth parameters. The results were L ¥ = 294.9 cm, W ¥ = 198690.1 g, K = 0.029 year )1 ; t 0 = )2.2 year. The D. pastinaca diet was composed mainly of crustaceans.

Nursery habitat use and foraging ecology of the brown stingray Dasyatis lata determined from stomach contents, bulk and amino acid stable isotopes

“…A previous study that used stable isotopic compositions of amino acids found a TEF of 3.6 ‰ more accurately represented penguin TPs (Lorrain et al 2009). That difference was attributed to the use of blood samples for isotopic analysis, whereas earlier studies had used whole animal or muscle tissue (McClelland & Montoya 2002, Chikaraishi et al 2007, 2009, Popp et al 2007, Hannides et al 2009).The use of muscle in the present study precludes tissue biochemical effects as a viable explanation for the lower observed TEF from amino acid analysis. Alternatively, lower observed TEFs in brown stingray and juvenile scalloped hammerhead shark muscle may be due to lower reaction rates involving glutamic acid as a consequence of urea retention for osmotic regulation (Evans et al 2004).…”

“…Alpheids are a common prey item for dasyatids from Florida and the eastern Mediterranean Sea (Snelson & Williams 1981, Yeldan et al 2009), whereas portunids were common in the diets of dasyatids from the central Bahamas and the western Atlantic Ocean (Struhsaker 1969, Gilliam & Sullivan 1993. Site-specific differences in prey abundances probably contribute to a lower importance of crustaceans for some dasyatid rays.…”

“…A previous study that used stable isotopic compositions of amino acids found a TEF of 3.6 ‰ more accurately represented penguin TPs (Lorrain et al 2009). That difference was attributed to the use of blood samples for isotopic analysis, whereas earlier studies had used whole animal or muscle tissue (McClelland & Montoya 2002, Chikaraishi et al 2007, 2009, Popp et al 2007, Hannides et al 2009). …”

“…These values may be difficult to obtain in habitats such as coral reefs, which have a diverse range of primary producers, or in deep water habitats that are not easily sampled. Recent studies have shown that analysis of the isotopic composition of individual amino acids (as opposed to bulk tissue) taken from a consumer can circumvent these challenges , Fantle et al 1999, McClelland & Montoya 2002, Chikaraishi et al 2007, 2009, 2010, Popp et al 2007, Hannides et al 2009, Lorrain et al 2009). This is because the δ 15 N values of some amino acids, such as phenylalanine, retain the δ 15 N values of primary producers.…”

“…1999, McClelland & Montoya 2002, Chikaraishi et al. 2007, 2009, 2010, Popp et al 2007, Hannides et al 2009, Lorrain et al 2009). This is because the δ (Pakhomov et al 2004, Schmidt et al 2004, Popp et al 2007, Chikaraishi et al 2009, Hannides et al 2009, Lorrain et al 2009), yet TP has only been estimated for a single elasmobranch (Chikaraishi et al 2010).…”