A novel approach for directly incorporating disease into fish stock assessment: a case study with seroprevalence data

When estimating mortality from disease with fish population models, common surveillance data such as infection prevalence are not always informative, especially for fast-acting diseases that may go unobserved in infrequently sampled populations. In these cases, seroprevalence — the proportion of measurable antibody levels their blood be more informative. cases life-long immunity, require less frequent sampling intervals than and can reflect cumulative exposure history fish. We simulation tested usefulness an age-structured stock assessment model using viral hemorrhagic septicemia virus (VHSV) Pacific herring (Clupea pallasii) a case study. developed novel epidemiological to simulate dynamics fitted integrated catch-at-age equations estimate age- time-varying disease. found simulated provide accurate estimates disease-associated mortality. Importantly, even models misspecified nonstationary processes background or mortality, but included data, accurately estimated annual abundance.