Smelt fatty acid and stable isotope data from three Swedish large lakes

<p>These data correspond to a study of Eurasian smelt from three Swedish lakes: Hjälmaren, Mälaren and Vättern: “<em>Stable isotope and fatty acid variation of a planktivorous fish among and within large lakes</em>” in PloS ONE.</p>

<p>Smelt were collected from the three lakes during July-September 2016 by the Swedish University of Agricultural Sciences, using gillnets in Mälaren and Hjälmaren and trawling onboard R/V Asterix on Vättern. Fish were frozen and dissected upon collection. Dorsal muscle samples were taken for fatty acid and stable isotope analyses.</p>

<p>Stable isotopes were measured at University of California-Davis Stable Isotope Facility (stableisotopefacility.ucdavis.edu/) using an elemental analyzer (PDZ Europa ANCA-GSL) interfaced to a continuous flow isotope ratio mass spectrometer (PDZ Europa 20-20). Sample isotope ratios were expressed as δ<sup>13</sup>C and δ<sup>15</sup>N, relative to international standards: Vienna Pee Dee beleminite (δ<sup>13</sup>C) and atmospheric N<sub>2</sub> (δ<sup>15</sup>N).</p>

<p>Fatty acids were quantified at Purdue University’s Department of Forestry and Natural Resources using a Shimadzu gas chromatograph model GC-2010 with flame ionization detector, autoinjector, and EZStart software version 7.4 (Shimadzu Corp.; <a href="http://www.shimadzu.com">www.shimadzu.com</a>). Fatty acid values are expressed as proportional composition by mass, with proportion calculated among the 12 fatty acids that represented >1% of total fatty acid mass by sample median.</p>