Selecting MBP Broodstock

Typically, Pacific oysters reach market-size in the Pacific Northwest after two years in the field. MBP tries to allow each cohort of families to be exposed to two full growing seasons (i.e. Spring, Summer and Fall). Exposing two-year old oysters to elevated water temperatures during the Summer and Fall in the field is especially important in selecting for resistance to summer mortality syndrome.

Harvest involves recording the total weight of all live animals in each of the 8 replicate bags per each of the 60 families, for a total of 480 replicate bags per site. In addition, survival is recorded for each replicate bag. Families are then ranked by average bag weight (i.e. live weight yield).

MBP selects the largest individuals from the highest yielding families to serve as parents for future generations. Remaining oysters from the highest yield families are set aside for industry use. Finally, non-top-performing families are given to the host farm to sell.