Most aquaculture producers are exposed to a number of biophysical factors impacting the production cycle. For some species this leads to significant seasonality in the harvesting process, potentially creating market and price cycles. Salmon is a species where there is significant price volatility as well as seasonality in the harvest patterns. For instance, there is a strong seasonal peak in Norwegian salmon production associated with the Christmas season. In this paper we will investigate to what extent the seasonal patterns in harvest in the Norwegian salmon industry are driven by biophysical or market factors. Moreover, we will investigate to what extent regional differences in harvest patterns exacerbate the general patterns or whether they cancel each other out as farmers in different regions use them to their best advantage.