The preovulatory hydration of teleost oocytes is a unique process among vertebrates. The hydration mechanism is most pronounced in marine acanthomorph teleosts that spawn pelagic (floating) eggs; however, the molecular pathway for water influx remains poorly understood. Recently, we revealed that whole-genome duplication (WGD) resulted in teleosts harboring the largest repertoire of molecular w...

In teleostean bony fishes, studies on the adults of various species have shown that pineal photoreceptors are maximally sensitive to short- and middle-wavelength light, possibly utilising both rod-like and pineal-specific opsins. Until recently, however, very little was known about the pineal opsins present in embryonic and larval teleosts and their relationships to opsins expressed by retinal ...

Despite the increasingly positive reviews of individual transferable quotas (ITQs), few studies have considered how quota leasing activities can reduce the economic benefits to society and to fishermen operating under the ITQ fisheries system. This analysis reveals negative economic impacts of ITQs previously overlooked by examining the extent of quota leasing and the relationship between the c...

................................................................................................................. 55

Immunoglobulin (IgM) was isolated from the serum of four fish species, Atlantic salmon (Salmo salar L.), halibut (Hippoglossus hippoglossus L.), haddock (Melanogrammus aeglefinus L.) and cod (Gadus morhua L.) and a comparison made of some physical and biochemical properties. The molecular weight of IgM varied between the different species and between the different analytical methods used. IgM f...

In this study, the gonadotropin-releasing hormone (GnRH) genes in spotted halibut were cloned and sequenced by isolating their cDNAs. The species expressed three molecular forms of GnRH in the brain: chicken-type GnRH-II (cGnRH-II), seabream-type GnRH (sbGnRH), and salmon-type GnRH (sGnRH). Phylogenetic analysis divided the molecular forms of GnRHs into three branches: cGnRH-II branch, sGnRH br...

We characterized small-scale movement patterns and habitat of acoustic-tagged adult (68 to 220 cm total length) female Pacific halibut during summer and fall in Glacier Bay National Park, Alaska, a marine protected area (MPA). We used net squared displacement ana lysis methods to identify 2 movement states, characterize individual dispersal patterns, and relate habitat variables to movement sca...

Experimental horizontal transmission of nervous necrosis virus (NNV) originating from halibut Hippoglossus hippoglossus was studied through cohabitation of intraperitoneally (i.p.) injected fish with uninfected fish for 125 d. The experimental groups consisted of i.p. injected turbot Scophthalmus maximus or i.p. injected Atlantic salmon Salmo salar with turbot, salmon or Atlantic cod Gadus morh...

In the early 1990s, the Northwest Atlantic Ocean underwent a fisheries-driven ecosystem shift. Today, the iconic cod (Gadus morhua) remains at low levels, while Atlantic halibut (Hippoglossus hippoglossus) has been increasing since the mid-2000s, concomitant with increasing interest from the fishing industry. Currently, our knowledge about halibut ecology is limited, and the lack of recovery in...