Was that my meal? Uncertainty from source sampling period in diet reconstruction based on stable isotopes in a syngnathid fish

Stable isotopes can be used to reconstruct diet in fishes, an approach that is particularly useful threatened or endangered species where lethal sampling needs avoided To apply this method stable need measured both the consumers and dietary sources As turnover rates may largely differ across tissues, reconstruction should consider uncertainty associated with timing for sources. The present study investigated first time application of a lag estimation trophic position regime greater pipefish Syngnathus acus (Family Syngnathidae). For that, two isotopic (δ 13 C δ 15 N) data sets from dorsal fin-clipped tissues were used, including values potential sampled (a) concomitantly (Unshifted approach) (b) season preceding consumer (Shifted approach). results attained indicate was not affected (< 0.6% change) by shifting when analyzed annual dataset (global assessment). However, level estimated shifted treatment ca. 6% higher than unshifted analysis performed using seasonal (seasonal assessment exclusively specimens collected summer). Regarding comparison approach, revealed preference amphipods (43.7%), isopods (19.5%) mysidaceans (12.1%), reduction reconstructed abundance harpacticoid copepods (5.1%). These findings similar those food web components same period dataset), females males. This demonstrates (1) variability estimates regimes depending on applied, (2) importance considering adequate lags syngnathid fishes.