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Book Social Interaction Between Juvenile Coho and Fall Chinook Salmon in Sixes River  Oregon

Download or read book Social Interaction Between Juvenile Coho and Fall Chinook Salmon in Sixes River Oregon written by Roy A. Stein and published by . This book was released on 1971 with total page 100 pages. Available in PDF, EPUB and Kindle. Book excerpt: The nature of the interaction between juvenile coho salmon, Oncorhynchus kisutch (Walbaum), and fall chinook salmon, 0. tshawytscha (Walbaum), was studied in Sixes River, Oregon. Seining, snorkeling, and tagging were used to determine distribution and patterns of growth of these two species in the stream environment. Experiments conducted in flowing-water observation troughs that provided volitional residence were designed to examine the outcome of agonistic behavior between these two species. Both species were distributed throughout the entire river system in early spring. During this period, underwater surveys in the main river and selected tributaries indicated that both species preferred the same habitat. As temperatures increased during the late spring, coho disappeared from the main river, but continued to occupy cool tributaries. Fall chinook, on the other hand, were found primarily in the main river until early summer, when they moved to the estuary. Relatively few individuals remained in the tributaries. Experiments conducted in the troughs revealed that agonistic behavior, including nipping, chasing, lateral display, submission, and fleeing, occurred between juvenile coho and fall chinook. When the two species were together in the troughs and in cool tributary streams, coho grew faster than chinook. When isolated in troughs, both grew at similar rates. Coho tolerated fewer individuals per unit area than did chinook, and occupied positions of dominance near the source of incoming food at the upstream end of the troughs. Coho had brighter fin and body colors, greater fin development, deeper bodies, and were heavier than fall chinook of the same length. Coloration and morphology appeared to be important factors influencing the "apparent" size and presumably the social status of both species. Juvenile coho, with extensive development of fins and coloration and intense territorial behavior, are hypothesized to be adapted to small, cool tributary streams. Fall chinook, on the other hand, with conservative development of fins and coloration and related behavior patterns, appear to be adapted to conditions in the main river and estuary.

Book Chinook Salmon Populations in Oregon Coastal River Basins

Download or read book Chinook Salmon Populations in Oregon Coastal River Basins written by J. W. Nicholas and published by . This book was released on 1989 with total page 388 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Canadian Journal of Fisheries and Aquatic Sciences

Download or read book Canadian Journal of Fisheries and Aquatic Sciences written by and published by . This book was released on 1988 with total page 790 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Population Dynamics of Fall Chinook Salmon in Sixes River

Download or read book Population Dynamics of Fall Chinook Salmon in Sixes River written by Paul E. Reimers and published by . This book was released on 1982 with total page 27 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Fecundity of Fall Chinook Salmon in Sixes River  Oregon

Download or read book Fecundity of Fall Chinook Salmon in Sixes River Oregon written by Paul E. Reimers and published by . This book was released on 1975 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Selective Predation  Optimal Foraging  and Resource Depression Within the Predator prey Interaction Between Fish and Crayfish

Download or read book Selective Predation Optimal Foraging and Resource Depression Within the Predator prey Interaction Between Fish and Crayfish written by Roy A. Stein and published by . This book was released on 1975 with total page 436 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Investigations Into the Early Life History of Naturally Produced Spring Chinook Salmon in the Grande Ronde Riiver Basin

Download or read book Investigations Into the Early Life History of Naturally Produced Spring Chinook Salmon in the Grande Ronde Riiver Basin written by and published by . This book was released on 1997 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: Historically, the Grande Ronde River produced an abundance of salmonids including stocks of spring, summer and fall chinook salmon, sockeye salmon, coho salmon, and summer steelhead. During the past century, numerous factors have caused the reduction of salmon stocks such that only sustainable stocks of spring chinook salmon and summer steelhead remain. The sizes of spring chinook salmon populations in the Grande Ronde River basin also have been declining steadily and are substantially depressed from estimates of historic levels. In addition to a decline in population abundance, a reduction of spring chinook salmon spawning distribution is evident in the Grande Ronde River basin. Numerous factors are thought to contribute to the decline of spring chinook salmon in the Snake River and its tributaries. These factors include passage problems and increased mortality of juvenile and adult migrants at mainstem Columbia and Snake river dams, overharvest, and habitat degradation associated with timber, agricultural, and land development practices. This study was designed to describe aspects of the life history strategies exhibited by spring chinook salmon in the Grande Ronde River basin. During the past year the focus was on rearing and migration patterns of juveniles in the upper Grande Ronde River and Catherine Creek. The study design included three objectives: (1) document the annual in-basin migration patterns for spring chinook salmon juveniles in the upper Grande Ronde River and Catherine Creek, including the abundance of migrants, migration timing and duration; (2) estimate and compare smolt survival indices to mainstem Columbia and Snake river dams for fall and spring migrating spring chinook salmon; and (3) determine summer and winter habitat utilization and preference of juvenile spring chinook salmon in the upper Grande Ronde River and Catherine Creek.

Book Racial Identification of Chinook Salmon  Oncorhynchus Tshawytscha  and Juvenile Steelhead Trout  Salmo Gairdneri

Download or read book Racial Identification of Chinook Salmon Oncorhynchus Tshawytscha and Juvenile Steelhead Trout Salmo Gairdneri written by James T. Martin and published by . This book was released on 1978 with total page 64 pages. Available in PDF, EPUB and Kindle. Book excerpt: Efforts to manage stocks of salmonids in Pacific Northwest stream systems are complicated by the occurrence of several runs of a species thought to represent races rearing sympatrically as juveniles. In order to collect the population statistics needed to properly manage these stocks, managers need a method of identifying juvenile salmonids by race. In an effort to determine if taxonomic or morphological differences exist between these races, wild juvenile summer and winter steelhead trout (Salmo gairdneri) and wild juvenile spring and fall chinook salmon (Oncorhynchus tshawytscha) from the Rogue River (Oregon) were studied. The goal of the study was to determine if differences in taxonomic characters would allow racial identification of individual fish with 90% accuracy. The wild juvenile summer steelhead trout had significantly fewer vertebrae and larger nuclei, greater average intracircular spacing, and a larger length at first annulus formation of scales than winter steelhead trout. No differences between juvenile summer and winter steelhead trout were found in otolith nuclear diameter, total lipids or fatty acid composition of the muscle tissue. Wild juvenile spring chinook salmon exhibited significantly lower vertebral counts, larger otolith nuclear diameter, greater average intracircular spacing, larger scale nuclei, and a larger first and second band of five intracircular spaces than juvenile fall chinook salmon. Mesentary fat deposition was highly variable between fish from the same streams and was not useful in separating juveniles by race. Although significant differences between races were found for both species, none of these differences were sufficient to allow the racial identification of individual fish with 90% accuracy. It is not known if the differences found were caused by genetic or environmental effects or both. One experiment showed that summer and winter steelhead showed no difference in vertebrae or otolith dimensions when incubated under the same conditions, suggesting that differences found in wild steelhead trout were caused by environmental effects. The lack of distinct phenotypic differences between individual fish of different races may be caused by extensive interbreeding between races of salmonids in the Rogue Basin due to large environmental variability during the spawning season for chinook salmon and steelhead trout. It is also possible that environmental variation in the early life history masked genetic differences between the races.

Book Distribution  Habitat Use  and Growth of Juvenile Chinook Salmon in the Metolius River Basin  Oregon

Download or read book Distribution Habitat Use and Growth of Juvenile Chinook Salmon in the Metolius River Basin Oregon written by Jens C. Lovtang and published by . This book was released on 2005 with total page 210 pages. Available in PDF, EPUB and Kindle. Book excerpt: Chinook salmon (Oncorhynchus tshawytscha) have been absent from their historic spawning and rearing grounds in the Metolius River Basin in central Oregon since 1968, when fish passage was terminated at the Pelton Round Butte Hydroelectric Project on the Deschutes River. Plans have been developed to reestablish passage of anadromous fish through the Project. However, only anecdotal evidence exists on the historic distribution of spring Chinook juveniles in the Basin. A recent approach to characterizing habitat quality for anadromous fishes in the Basin was the development of HabRate (Burke et al. In Press), which presented a relative quality rating of habitat based upon published fish-habitat relationships at the stream reach spatial scale. The present study was initiated to test the predictions of HabRate for summer rearing juvenile Chinook salmon in the Metolius Basin. Chinook salmon fry were released in the winters of 2002 and 2003, and their densities and sizes were quantified via snorkeling and fish collection in six unique study reaches in the upper Metolius River Basin. Each of these stream reaches varied in terms of temperature, habitat availability, invertebrate drift availability, and fish community composition. My observations were not consistent with the qualitative predictions of HabRate. Moreover, habitat utilization was not consistent among study reaches. Similar to other qualitative habitat rating models (e.g. Habitat Suitability Indices (Raleigh et al. 1986) and Instream Flow Incremental Methodology (Bovee 1982)), HabRate's predictions rely solely on physical habitat characteristics, with the assumption that habitat will be used consistently among stream reaches (i.e. a pool in one reach is of equal importance as a pool in another reach). My results suggest that the unique ecological setting of each study reach provides the context for understanding the patterns of growth, habitat use, and diurnal activity of juvenile Chinook salmon. The inclusion of ecological components, such as food availability, the bioenergetic constraints of temperature, and the risk of predation can make these models more biologically realistic. Growth of juvenile Chinook salmon among study reaches had a curvilinear relationship to water temperature, and was also positively related to the drift density of invertebrate biomass. In three collection seasons (fall 2002, spring 2003 and fall 2003) 41 to 69% of the variations in fork lengths were explained by a multiple regression model including temperature and invertebrate drift. Based on these findings, I present a conceptual growth capacity model based on the tenets of bioenergetics as a basis for understanding the relative quality of the habitat among stream reaches for juvenile Chinook salmon. Fish community composition can help to explain observed patterns in habitat utilization and diel activity patterns. In the study reaches that had a greater presence of adult trout (potential predators), observations of juvenile Chinook salmon in mid-channel habitat were infrequent to non-existent during the day and abundances were higher in all habitat types at night. In the study reaches with colder water temperatures, observed juvenile Chinook salmon densities were higher at night. I suggest that habitat selection and diurnal activity patterns in some study reaches are reflective of strategies taken by the fish to minimize risks of predation.

Book Investigations Into the Early History of Naturally Produced Spring Chinook Salmon in the Grand Ronde Basin

Download or read book Investigations Into the Early History of Naturally Produced Spring Chinook Salmon in the Grand Ronde Basin written by and published by . This book was released on 1998 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt: We have documented two general life history strategies utilized by juvenile spring chinook salmon in the Grande Ronde River basin: (1) juveniles migrate downstream out of summer rearing areas in the fall, overwinter in river valley habitats, and begin their seaward migration in the spring, and (2) juveniles remain in summer rearing areas through the winter and begin seaward migration in the spring. In migration year 96-97, the patterns evident from migrant trap data were similar for the three Grande Ronde River populations studied, with 42% of the Lostine River migrants and 76% of the Catherine Creek migrants leaving upper rearing areas in the fall. Contrary to past years, the majority (98%) of upper Grande Ronde River migrants moved out in the fall. Total trap catch for the upper Grande Ronde River was exceedingly low (29 salmon), indicating that patterns seen this year may be equivocal. As in previous years, approximately 99% of chinook salmon juveniles moved past our trap at the lower end of the Grande Ronde River valley in the spring, reiterating that juvenile chinook salmon overwinter within the Grande Ronde valley section of the river. PIT-tagged fish were recaptured at Grande Ronde River traps and mainstem dams. Recapture data showed that fish that overwintered in valley habitats left as smolts and arrived at Lower Granite Dam earlier than fish that overwintered in upstream rearing areas. Fish from Catherine Creek that overwintered in valley habitats were recaptured at the dams at a higher rate than fish that overwintered upstream. In this first year of data for the Lostine River, fish tagged during the fall migration were detected at a similar rate to fish that overwintered upstream. Abundance estimates for migration year 96-97 were 70 for the upper Grande Ronde River, 4,316 for the Catherine Creek, and 4,323 for the Lostine River populations. Although present in most habitats, juvenile spring chinook salmon were found in the greatest abundance in pool habitats, particularly alcove and backwater pools. These results were consistent for both summer and winter surveys.

Book Olfactory Imprinting and Homing in Salmon

Download or read book Olfactory Imprinting and Homing in Salmon written by A.D. Hasler and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 152 pages. Available in PDF, EPUB and Kindle. Book excerpt: Chance Favors Only the Prepared Mind How does a scientist go about the task of pushing back the curtains of the unknown? Certainly the romance of tackling the mysteries of nature provides the motivation, for who would not be inspired by the remarkable life history of this romantic beast, the salmon. After living in the Pacific Ocean for several years, salmon swim thousands of kilometers back to the stream of their birth to spawn. I have always been fascinated by the homing migration of salmon. Noone who has seen a 20-kilogram salmon fling itself into the air repeatedly until it is exhausted in a vain effort to surmount a waterfall can fail to marvel at the strength of the instinct that draws the salmon upriver to the stream where it was born. But how does it find its way back? I was puzzling over this problem during a family vacation in 1946. Inspired by the work of the great German Nobel Laureates, Karl von Frisch and Konrad Lorenz, I had been conducting research with my graduate student Theodore Walker, since 1945, on the ability of fishes to discriminate odors emanating from aquatic plants. Von Frisch had studied schooling minnows and discovered that, if broken, their skin emitted a con specific chemical substance, termed Schreckstoff, which caused other members of its school to disperse and hide.