Prevalence of stocked whitefish in River Kemijoki, Finland, inferred by micro X-ray fluorescence analysis of otoliths
Erkki Jokikokko; Martina Blass; Viktor Finnäs; Yann Lahaye; Jan-Olof Lill; Yvette Heimbrand; Henry Hägerstrand; Timo Saarinen
Prevalence of stocked whitefish in River Kemijoki, Finland, inferred by micro X-ray fluorescence analysis of otoliths
Erkki Jokikokko
Martina Blass
Viktor Finnäs
Yann Lahaye
Jan-Olof Lill
Yvette Heimbrand
Henry Hägerstrand
Timo Saarinen
WILEY
Julkaisun pysyvä osoite on:
https://urn.fi/URN:NBN:fi-fe2021042826386
https://urn.fi/URN:NBN:fi-fe2021042826386
Tiivistelmä
Micro X-ray fluorescence (mu-XRF) analysis of otoliths was evaluated as a method to estimate the proportion of stocked one-summer-old whitefish Coregonus lavaretus L. in catches of adult fish (n = 20) ascending the River Kemijoki to spawn. Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) analysis was applied as control. Polished otoliths were scanned with mu-XRF to obtain strontium maps that were used to infer visually the provenance of the whitefish. Thirteen of the fish showed signs of being stocked as one-summer-old fingerlings. LA-ICP-MS was applied to determine the elemental composition in a spot outside the core of the otolith. The results were largely consistent with the visual inspection of the mu-XRF mapped otoliths. In conclusion, mu-XRF mapping successfully identified whitefish stocked as one-summer-old fingerlings. The vast majority of whitefish returning to the River Kemijoki to spawn were stocked fish.
Kokoelmat
- Rinnakkaistallenteet [19206]