I'm not sure of any sepcific lipid-calcium linkages. tIn experimental systems it's difficult to distingangle co-incident temporal fluctautaions in lipid and protein metabolism. Protein metabolism (linked to reproduction and condition) has a strong co-variance with blood calcium  - but as endolymph Ca is strongly regulated, I don't think this would be expected to be reflected in the otolith.

Classic work by Kalish is probably the best reference still, we also recently published linkages between envionment, physiology and  blood metal chemistry:

Sturrock et al 2014 Physiological influences can outweigh environmental signals in otolith microchemistry research MEPS 500: 245–264

doi: 10.3354/meps10699

Thanks very much for your answer