TWO STRATEGIES HAVE BEEN PROPOSED TO AVOID NEGATIVE GENETIC EFFECTS OF ARTIFICIALLY PROPAGATED INDIVIDUALS ON WILD POPULATIONS: (i) integration of wild and captive populations to minimize domestication selection and (ii) segregation of released individuals from the wild population to minimize interbreeding. We tested the efficacy of the strategy of segregation by divergent life history in a ste...

Pacific threadfin, Polydactylus sexfilis, is popular fish in recreational fishing, as well as aquaculture in Hawaii. Its natural population has been continuously declining in the past several decades. Microsatellite DNA markers are useful DNA-based tool for monitoring Pacific threadfin populations. In this study, fifteen Microsatellite (MS) DNA markers were identified from a partial genomic Pac...

The release of hatchery-reared fishes for restoring threatened and endangered populations is one of the most controversial issues in applied ecology. A central issue has been to determine whether releases cause extinction of local wild populations. This may arise either through domesticated or non-local fishes hybridizing with wild fishes, or through inappropriate behavioural interactions; for ...

The extent to which stray, hatchery-reared salmon affect wild populations is much debated. Although experiments show that artificial breeding and culture influence the genetics of hatchery salmon, little is known about the interaction between hatchery and wild salmon in a natural setting. Here, we estimated historical and contemporary genetic population structures of chum salmon (Oncorhynchus k...

Salmon produced by hatcheries have lower fitness in the wild than naturally produced salmon, but the factors underlying this difference remain an active area of research. We used genetic parentage analysis of alevins produced by experimentally mixed groups of wild and hatchery coho salmon (Oncorhynchus kisutch) to quantify male paternity in spawning hierarchies. We identify factors influencing ...

Naïve, hatchery-reared Atlantic salmon Salmo salar parr were paired with demonstrators that had been pre-trained to accept live prey from the surface or from the benthos. After 6 days of observing demonstrators through a clear perspex partition the naïve fish’s benthic foraging skills were tested. The results revealed that hatchery-reared Atlantic salmon can be taught to target benthic prey ite...

Single-round polymerase chain reaction (PCR) and pepsin-trypsin digest (PTD) methods were compared for the detection of Myxobolus cerebralis. Parallel tests were conducted on a total of 1743 free-ranging and 400 hatchery-reared salmonids. Concurrent results were found in 84.6% of the free-ranging fish samples, and 83.5% of the hatchery samples. PCR identified M. cerebralis more frequently than ...

For over a century, harvests of eastern oysters (Crassostrea virginica) have been declining in the northeast. This trend has been particularly acute in the mid-Atlantic region where two diseases, MSX and Dermo, have caused catastrophic mortalities. With the reduction in natural populations, growers have increasingly turned to the use of hatchery technology for annual supplies of seed oysters. T...