Early questions in this category mostly concerned culture practices which introduced artificial selection, such as selectively spawning the largest fish or the earliest-returning fish, or mixing the milt of several males prior to fertilization. Hatchery managers must also make a large number of decisions about the spawning process which may impact genetic diversity, including numbers and ratios of males to females, spawning protocols (1:1, matrix, partial matrix), the rate at which different age classes (e.g., jacks) are incorporated, and more. Answers to these questions depend on the program objectives, the limitations of the facility, and the biology of the species. By contributing our genetics expertise, we help hatchery managers and co-managers understand the risks and benefits associated with various culture practices.