Table S5. Seasonal variation in resource use of whitefish in L. Kilpis Month December February May June July September Muscle Pelagic 19 (14 - 26) 24 (19 - 30) 19 (14 - 24) 18 (6 - 30) 17 (11 - 23) 20 (14 - 25) Littoral 21 (18 - 25) 21 (17 - 24) 29 (26 - 32) 23 (16 - 30) 25 (21 - 28) 26 (23 - 30) Profundal 59 (53 - 65) 55 (48 - 61) 52 (46 - 58) 59 (47 - 72) 58 (52 - 65) 54 (48 - 60) SEAc 1.54 1.23 1.89 1.99 1.54 1.09 Liver Pelagic 18 (10 - 26) 18 (10 - 26) 16 (9 - 23) 11 (10 - 24) 33 (26 - 40) 32 (26 - 40) Littoral 40 (35 - 44) 33 (29 - 38) 33 (29 - 37) 40 (33 - 47) 27 (23 - 31) 42 (38 - 46) Profundal 42 (35 - 50) 49 (40 - 56) 51 (45 - 59) 49 (35 - 61) 40 (33 - 47) 26 (17 - 33) SEAc 4.78 4.19 4.26 3.69 2.58 2.49 Mode contribution of pelagic, littoral and profundal resources to muscle and liver stable isotope values of whitefish as determined by the SIAR mixing model. 95% credibility limits are provided in parentheses. Mean isotope niche width (SEAc) of each population is also provided.