Juvenile English sole, Parophrys vetulus utilize Yaquina Bay, Oregon, as a nursery during at least a portion of their first year of life, but the possibility of the existence of additional nursery grounds offshore has not previously been examined. During 1971, young-of the-year first appeared in Yaquina Bay in February,...
Pandalis jordani Rathbun, like many other species of pandalid shrimps, undergo regular diel changes in their vertical distribution (Tegelberg and Smith 1957; Alverson et al. 1960; Pearcy 1970, 1972; Robinson in press). Little is known, however, about the vertical distribution and diel migrations of larval and juvenile shrimp, or at...
Beginning in the late 1960s and throughout the past decade, unusual, perhaps neoplastic, large cells with rather consistent characteristics were described in mussels, clams, and oysters from several bays in the United States and the United Kingdom. The large, characteristic cells are thought by many workers to be abnormal leukocytes...
Experiments were performed to determine the rate of recolonization of sediment-associated microalga and effects of infauna on microalgal biomass and production. Estuarine sediment was defaunated and transplanted to the field and the laboratory. Recolonization of sediment by flora and fauna, relative to control sediment, was measured by chlorophyll a, gross...
Patterns of seasonal abundance of harbor seals at Netarts and Tillamook Bays, Oregon, were documented by recording numbers of seals hauling out on tidally exposed sand flats in both bays. Harbor seal abundance at Tillamook Bay peaked during pupping (May-June) and molting (August) periods, while peak abundance at Netarts Bay...
Sediment-associated microalgal biomass expressed as chlorophyll a concentration, total organic matter concentration expressed as ash-free dry weight, and hourly rates of net community primary production and community oxygen consumption were measured at monthly intervales at medium sand, fine sand, and silt sites between 0.5 and 2.0 m above MLLW during...
Juvenile red hake Urophycis chuss were collected while they were inhabiting sea scallops Placopecten magellanicus , and the effects of appetite and food availability on prey consumption and growth were examined under laboratory conditions. Fish took increasing amounts of live amphipods Gammarus annulatus with increasing periods of food deprivation up...
The food habits of the 2 dominant larval pleuronectids off the Oregon coast - English sole Parophrys vetulus and butter sole Isopsetta isolepis - were analysed. Most specimens were collected during January-April 1971 and March-April 1973. As is typical of larval fishes, I. isolepis larvae ingested a variety of prey...
Behavioral responses of juvenile bluefish P. saltatrix L. exposed to cold water in a vertical thermal gradient were measured under controlled laboratory conditions. The temperature regime was similar to conditions that these fish encounter in their inshore and estuarine habitats along the Middle Atlantic coast. Measures included activity, schooling, position...
A simple behavioral test was devised to determine the effects of multiple acute stresses on the avoidance response time of fish. Groups of freshwater-adapted juvenile chinook salmon Oncorhynchus tshawytscha were exposed to a sudden overhead light and the time it took each fish to reach cover was noted. Tests were...
Neutralizing monoclonal antibodies were developed against strains of infectious hematopoietic necrosis virus (IHNV) from steelhead trout Salmo gairdneri in the Deschutes River of Oregon, chinook salmon Oncorhynchus tshawytscha in the Sacramento River of California, and rainbow trout Salmo gairdneri reared in the Hagerman Valley of Idaho, USA. These antibodies were...
We examined the diets and weight-length relationships of juvenile bluefish Pomatomus saltatrix from Sandy Hook Bay, New Jersey, during 1981, 1983, and 1984. Diets consisted of a variety of polychaete, crustacean, and fish prey. Opossum shrimp Neomysis americana. sand shrimp Crangon septemspinosa, grass shrimp Palaemonetes vulgar is, bay anchovy Anchoa...
Rockfishes, Sebastes spp.. were the most numerous and speciose fishes seen during 16 submersible dives from 64 to 305 m depth in the vicinity of Heceta Bank off the coast of Oregon. Dense schools of juvenile rockfishes and large yellowtail rockfish, S. flavidus, were observed only over rocky, high relief...
We quantified both in situ predation on Pacific herring (Clupea haregus pallasi ) larvae by soft-bodied zooplankton, and microzooplankton prey of herring larvae in Kulleet Bay, Vancouver Island, British Columbia. Samples were collected at 0 to 5 m depth daily at peak larval hatching from 14 to 21 April 1985....
Abnormalities including contortion of the body and reduction of the jaws and pectoral
fins occurred among 2-25% of the yolk-sac Pacific herring larvae Clupea harengus pallasi collected in 1985 from Kulleet Bay, a spawning area on Vancouver Island, British Columbia. An additional 4-68% of the post-yolk-sac larvae had underdeveloped lower...
This study examined, under controlled laboratory conditions, behavioral responses of larval walleye pollock (4 to 8 mm) to various physical factors that may potentially play a role in vertical movements and distribution. Diel periodicity in vertical distribution was evident and appeared to be under exogenous control. During the day, with...
Cell lines were established from spleen and heart tissues of a juvenile white sturgeon Acipenser transmontanus and designated WSS-2 and WSH-1, respectively. Isoenzyme analyses of both lines confirmed their host of origin. Both lines were hypotetraploid and possessed micro- and macrochromosomes. The modal chromosome number for the WSS-2 line was...
Two species of salmonids were tested for their susceptibility to infection by a rickettsia isolated in cell culture from diseased coho salmon Oncorhynchus kisutch in Chile. Mortality approached 100% in coho and Atlantic salmon Salmo salar injected with 10-fold dilutions of cell culture medium containing the rickettsia. Typical disease signs...
An indirect fluorescent antibody test (IFAT) was developed for detection of the rickettsia that was causing epizootics among salmonids cultured in seawater net-pens in southern Chile. Antiserum against the rickettsial agent was produced in New Zealand white rabbits with a preparation grown in antibiotic-free chinook salmon embryo (CHSE-214) cell cultures...
The relationship between predator avoidance deficits induced by a simple handling stress and the level of plasma corticosteroids was determined for juvenile coho salmon Oncorhynchus kisutch. Groups of fish were held out of water for 1 min, then allowed to recover from this stress for 1, 90, or 240 min....