Use of Lanthanide Elements to Mass Mark Juvenile Salmonids

1993 ◽  
Vol 50 (5) ◽  
pp. 1039-1044 ◽  
Author(s):  
Bridget C. Ennevor ◽  
R. M. Beames
Keyword(s):  
Water Supply ◽  
Vertebral Column ◽  
Coho Salmon ◽  
Total Concentration ◽  
Oncorhynchus Kisutch ◽  
Juvenile Salmonids ◽  
Lanthanide Elements

Two experiments were conducted to evaluate the mass marking of coho salmon (Oncorhynchus kisutch) fry and smolts by the addition of lanthanide acetates to the water supply. The results demonstrated that lanthanides are absorbed from the water and are subsequently deposited in the vertebral column, otoliths, and scales of juvenile coho. Lanthanum and samarium applied at concentrations of 100 μg/L for 6 wk to fry resulted in the retention of detectable levels in bony tissues after 10.5 mo. When coho fry and smolts were exposed to various combinations of lanthanum and cerium at a total concentration in the water of 100 μg/L over a 4-wk period, residual mean amounts of lanthanides in the vertebral columns were greater in smolts than in fry.

Predation by River Otters (Lutra canadensis) on Juvenile Coho Salmon (Oncorhynchus kisutch) and Dolly Varden (Salvelinus malma) in Southeast Alaska

1993 ◽  
Vol 50 (2) ◽  
pp. 312-315 ◽  
Author(s):  
C. Andrew Dolloff
Keyword(s):  
Coho Salmon ◽  
Oncorhynchus Kisutch ◽  
River System ◽  
Dolly Varden ◽  
Salvelinus Malma ◽  
Southeast Alaska ◽  
River Otters ◽  
Juvenile Salmonids ◽  
Dolly Varden Salvelinus Malma ◽  
Lutra Canadensis

The effect of predation by river otters (Lutra canadensis) on juvenile coho salmon (Oncorhynchus kisutch) and Dolly Varden (Salvelinus malma) in a Southeast Alaska watershed was inferred by examining the number and size distribution of sagittal otoliths that were found in otter scats. Individual scats contained up to 408 otoliths, indicating that at least 200 fish had been eaten between defecations. Otoliths from juvenile salmonids outnumbered those from coastrange sculpins (Cottus aleuticus) by about six to one. Based on examination of over 8000 otoliths found in otter scats, at least 3300 juvenile salmonids were eaten by two river otters and their two young in the Kadashan River system during a 6-wk period in late spring 1985.

Apparent predation of juvenile coho salmon (Oncorhynchus kisutch) by prickly sculpins (Cottus asper) is an artefact of trapping methodology

2006 ◽  
Vol 57 (5) ◽  
pp. 513 ◽  
Author(s):  
Londi M. Tomaro
Keyword(s):  
Coho Salmon ◽  
Oncorhynchus Kisutch ◽  
Stomach Contents ◽  
Early Life History ◽  
Boreal Summer ◽  
Life Stages ◽  
Life History Stages ◽  
Juvenile Salmonids ◽  
Freshwater Sculpin ◽  
Trap Bias

Freshwater sculpins often inhabit the same waterways as juvenile salmonids and may impact the survival of juvenile salmonids through predation on early life-history stages. In the present study, the stomach contents of 2302 individual Cottus asper, a freshwater sculpin, collected from Auke Lake, Alaska, were examined during the boreal summer of 2000 to determine if C. asper are important natural predators of juvenile coho salmon (Oncorhynchus kisutch), and to explore possible trap bias of gear used in preliminary diet studies. The diet of sculpins collected in confining traps was compared with the diet of sculpins collected in nets. Significant predation on pre-smolt coho salmon by trapped sculpins, but none by netted sculpins, was observed. This result provides strong evidence of trap bias in the observed diet of C. asper. The remainder of the diet of trapped sculpins also differed significantly from that of netted sculpins. Significantly more trapped sculpins had eaten plant material and fish, whereas significantly more netted sculpins had consumed molluscs. Finally, sculpin diet was correlated with sculpin size, which may influence predation on other salmonid life-stages. These results expand our understanding of prickly sculpin diet and show that they are not important predators of juvenile coho salmon. These findings also demonstrate the importance of assessing the potential bias of collection gear and sampling techniques.

Neustonic feeding by juvenile salmonids in coastal waters of the Northeast Pacific

1989 ◽  
Vol 67 (8) ◽  
pp. 1995-2007 ◽  
Author(s):  
Richard D. Brodeur
Keyword(s):  
Coastal Waters ◽  
Coho Salmon ◽  
Oncorhynchus Kisutch ◽  
Near Surface ◽  
Larval Fishes ◽  
Northeast Pacific ◽  
Juvenile Salmonids ◽  
Terrestrial Origin ◽  
June July ◽  
Decapod Larvae

The near-surface macrozooplankton fauna off the Washington and Oregon coasts is described from a series of quantitative neuston hauls collected during June, July, and September 1984. Euphausiids, decapod larvae, hyperiid amphipods, and larval fishes were the dominant marine taxa represented. Insects of terrestrial origin were very common and occurred in high abundances, especially during the July and September cruises off Oregon, and their occurrence was coincident with unusual wind patterns. The neuston catches were quantitatively compared with the diets of juvenile coho (Oncorhynchus kisutch) and chinook (O. tshawytscha) salmon collected at the same stations and within the same cruises. There was an overall resemblance between the taxa in the neuston and stomachs of these salmon juveniles, although the larger organisms appeared to be consumed preferentially. Predominantly neustonic taxa also occurred in the diets of other juvenile salmonids and adult coho salmon collected concurrently, but these other predators did not appear to utilize neustonic prey to the same extent as coho and chinook juveniles.

Induced ovulation in coho salmon (Oncorhynchus kisutch). I. Further studies on the use of salmon pituitary preparations

Aquaculture ◽  
1981 ◽  
Vol 26 (1-2) ◽  
pp. 117-127 ◽  
Author(s):  
George A. Hunter ◽  
Edward M. Donaldson ◽  
Helen M. Dye
Keyword(s):  
Coho Salmon ◽  
Oncorhynchus Kisutch ◽  
Induced Ovulation

Physiological Response of Juvenile Coho Salmon (Oncorhynchus kisutch) and Rainbow Trout (Salmo gairdneri) to Handling and Crowding Stress in Intensive Fish Culture

1976 ◽  
Vol 33 (12) ◽  
pp. 2699-2702 ◽  
Author(s):  
Gary A. Wedemeyer
Keyword(s):  
Rainbow Trout ◽  
Feeding Behavior ◽  
Coho Salmon ◽  
Physiological Stress ◽  
Oncorhynchus Kisutch ◽  
Fish Distribution ◽  
Salmo Gairdneri ◽  
Crowding Stress ◽  
Normal Feeding ◽  
Intensive Fish Culture

Moving 4–5-in. coho salmon (Oncorhynchus kisutch) held in soft (20 ppm CaCO3) water from the relatively light loading density of 0.5 lb/ft3 to 1, 2, or 4 lb/ft3 (density index, DI = 0.1, 0.2, 0.4, 0.8) caused significant stress as indicated by loss of feeding behavior, but only minimal physiological disturbances, as indicated by lack of hyperglycemia or hypochloremia. However, moving them to 6 or 12 lb/ft3 (DI = 1.2, 2.4) caused significant physiological stress which required at least a week for recovery. Smolting coho salmon were physiologically stressed by population densities of 1 lb/ft3 or more and a subclinical corynebacterial kidney infection was activated. Rainbow trout (Salmo gairdneri) (4–5 in.) were physiologically stressed when moved and held at 1 lb/ft3 or more but retained normal feeding behavior. This indicates that handling and crowding stress will be minimized in softwater areas if densities in fish distribution trucks or in ponds or raceways during disease treatments are held to 0.1–0.5 lb/gal.

scholarly journals Hyperbilirubinemia of Coho Salmon Oncorhynchus kisutch Infected with Erythrocytic Inclusion Body Syndrome (EIBS) Virus

1994 ◽  
Vol 60 (5) ◽  
pp. 519-521 ◽  
Author(s):  
Tadashi Sakai ◽  
Hisashi Murata ◽  
Kiyoshi Yamauchi ◽  
Kiyotaka Takahashi ◽  
Nobuaki Okamoto ◽  
...  
Keyword(s):  
Inclusion Body ◽  
Coho Salmon ◽  
Oncorhynchus Kisutch
Sign in / Sign up

Export Citation Format

Share Document