Despite unprecedented scientific productivity, Earth is undergoing a sixth mass extinction. The disconnect between scientific output and species conservation may be related to scientists studying the wrong species. Given fishes have a high extinction rate, we assessed the paradox between scientific productivity and science needed for conservation by comparing scientific output created for critically endangered fishes and game fishes. We searched 197,866 articles (1964–2018) in 112 journals for articles on 460 critically endangered fishes, 297 game fishes, and 35 fishes classified as critically endangered and game fish—our analysis included freshwater and marine species. Only 3% of the articles in the final database were on critically endangered fishes; 82% of critically endangered fishes had zero articles. The difference between the number of articles on game fishes and critically endangered fishes increased temporally with more articles on game fishes during the extinction crisis. Countries with 10 or more critically endangered fishes averaged only 17 articles from 1964 to 2018. Countries with the most critically endangered fishes are most in need of science. More scientific knowledge is needed on critically endangered fishes to meet the challenges of conserving fishes during the sixth mass extinction.

Downstream escapement of fishes from reservoirs via release structures can represent a loss to populations that is comparable to natural and harvest mortality. Consequently, quantifying and managing fish escapement constitute a

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Fragmentation of rivers through anthropogenic modifications poses an imminent threat to the persistence of migratory fish, necessitating direct actions such as trap-and-haul programs to restore and conserve the migratory life-history component in populations of partially migratory species such as bull trout Salvelinus confluentus. We used a PIT-tag system to assess how biological and abiotic factors influence the out-migration dynamics of juvenile bull trout in Graves Creek, Montana, USA. The largest fish within a cohort were more likely to out-migrate at age 1 when compared to smaller fish within the cohort, and this was particularly evident in a high-density year-class (2018), where large bull trout out-migrated an average of 115 days earlier than bull trout in the medium size category, and 181 days earlier than bull trout in the small size category. Relative changes in abiotic factors, including discharge, water temperature, and photoperiod, appeared to act as cues to out-migration, with the direction of change varying by season. These results highlight the complex interplay between individual characteristics, population dynamics, and environmental conditions, which influence out-migration dynamics and can be used to inform management actions to conserve the migratory component in bull trout populations.

Trap‐and‐haul programs can maintain connection among habitats for migratory salmonids in fragmented systems. To conserve diversity within and among life history strategies, downstream trap and transport of juvenile salmonids could ideally mimic the natural, underlying out‐migration dynamics of the population. A two‐way trap‐and‐haul program is implemented in the lower Clark Fork River, Montana, to conserve adfluvial Bull Trout Salvelinus confluentus. We used PIT technology to assess whether downstream trapping efforts are effectively capturing variation in the out‐migration dynamics of juvenile Bull Trout in Graves Creek, a key spawning and rearing tributary in the system. We tagged 821 juvenile Bull Trout in Graves Creek and used these tagged Bull Trout in conjunction with stationary PIT antennas to monitor out‐migration and evaluate efficiency of the downstream trapping program. Capture efficiency in Graves Creek varied substantially from autumn to spring, with 89–96% of autumn out‐migrating Bull Trout captured and 5–10% of spring out‐migrating Bull Trout captured. Overall, we found that Bull Trout transported during the autumn out‐migration periods generally reflect the natural out‐migration dynamics of the population; however, Bull Trout that out‐migrate in the spring are currently underrepresented in the downstream transport program. By understanding the underlying out‐migration dynamics of the Bull Trout population in Graves Creek, management of the downstream trapping efforts can focus on minimizing potential selection for or against out‐migrants based on timing and age at out‐migration. Minimizing selection will conserve variation within the adfluvial life history strategy and therefore maximize resilience of the adfluvial Bull Trout populations.