Salmon carcasses as a marine-derived resource for benthic macroinvertebrates in a developing postglacial stream, Alaska

2008 ◽  
Vol 65 (7) ◽  
pp. 1342-1351 ◽  
Author(s):  
Kieran A. Monaghan ◽  
Alexander M. Milner
Keyword(s):  
Community Structure ◽  
Benthic Macroinvertebrates ◽  
Pink Salmon ◽  
Oncorhynchus Gorbuscha ◽  
Separate Experiment ◽  
Macroinvertebrate Communities ◽  
Southeast Alaska ◽  
Stream Macroinvertebrate ◽  
Experimental Approaches ◽  
And Control

Streams formed in Glacier Bay, southeast Alaska, following glacial recession rapidly support populations of spawning salmon. Using both observational and experimental approaches, we examined the importance of pink salmon ( Oncorhynchus gorbuscha ) carcasses for benthic macroinvertebrate communities, approximately 10 years after salmon first colonized Wolf Point Creek, a first-order, lake-fed stream. Macroinvertebrate abundance on carcasses naturally accumulating in the stream channel was low, dominated by chironomids ( Eukiefferiella spp.). Macroinvertebrate drift was significantly lower from artificial experimental channels containing salmon flesh (P < 0.001) compared with channels without. However, the density and community structure of macroinvertebrates colonizing rock baskets in channels was not significantly different between treatments. In a separate experiment, colonization of substrate trays with salmon and control (inert) fillets were associated with differences in community structure; simuliids dominated control fillets, and chironomids dominated fish fillets, while underlying stone substrate was colonized by a more diverse community including Ephemeroptera, Plecoptera, and Trichoptera taxa (EPT). Excluding simuliids, abundance was significantly higher on fish compared with control fillets (P < 0.001). These data suggest that scales and mucus prevent the direct consumption of flesh from whole carcasses, highlighting the role predators–scavengers in facilitating flesh consumption by benthic macroinvertebrates.

Possible Effects of the Sitka Eddy on Sockeye (Oncorhynchus nerka) and Pink Salmon (Oncorhynchus gorbuscha) Migration off Southeast Alaska

1986 ◽  
Vol 43 (2) ◽  
pp. 498-504 ◽  
Author(s):  
Kevin Hamilton ◽  
Lawrence A. Mysak
Keyword(s):  
Oncorhynchus Nerka ◽  
Pink Salmon ◽  
Oncorhynchus Gorbuscha ◽  
Surface Currents ◽  
Oceanic Circulation ◽  
Migration Routes ◽  
Southeast Alaska ◽  
Pink Salmon Oncorhynchus Gorbuscha ◽  
Northeast Pacific ◽  
Northeast Pacific Ocean

The interannual variability of sockeye (Oncorhynchus nerka) and pink salmon (Oncorhynchus gorbuscha) catches during 1952–62 from southeast Alaska and northern British Columbia is examined in relation to the appearance and disappearance of the Sitka eddy in the offshore oceanic circulation. In years when this large (~300 km in diameter) and intense (surface currents ~0.5 m/s) vortex is present, the spawning migration routes of salmon returning to the Nass and Skeena rivers tend to be deflected southward. An analysis of salmon tagging data collected during 1957 (when the eddy was absent) and 1958 (when the eddy was present) supports this conclusion. The southward deflection during 1958 is a particularly interesting result in light of many other observations which show that several fish species were displaced northward during the 1958 warming of the northeast Pacific Ocean.

Variations in Annual Average Weights of British Columbia Pink Salmon, 1944–1958

1959 ◽  
Vol 16 (3) ◽  
pp. 329-337 ◽  
Author(s):  
Harold Godfrey
Keyword(s):  
British Columbia ◽  
Pink Salmon ◽  
Oncorhynchus Gorbuscha ◽  
Steady Increase ◽  
Average Weight ◽  
Weight Changes ◽  
Southeast Alaska ◽  
Annual Changes ◽  
Average Size ◽  
Weight Data

Average weight data of British Columbia pink salmon, Oncorhynchus gorbuscha, since 1944 were made available by the Fisheries Association of British Columbia, and were used to compare annual changes in size among stocks throughout the Province. Adult pinks of the odd-year cycle were almost invariably larger than those of the even-year cycle. In British Columbia this cycle has also been consistently the more abundant, and in southeast Alaska these fish have been either about equally as numerous as the even-year pinks, or, upon occasion, much more numerous. The pink salmon of each of the major fishing areas in the Province show similar annual changes in average weight. From an extremely small average size in 1946 there was a trend of steady increase, among all stocks and involving both cycles, over the next 8 years; this was followed by a decline in 1955 and 1956, then a further increase in 1957 and 1958. A comparison between southeastern Alaska pinks and pinks of northern British Columbia showed that they had experienced similar year-to-year weight changes during the earlier period of 1930–1939.

Influence of salmon spawner densities on stream productivity in Southeast Alaska

1999 ◽  
Vol 56 (9) ◽  
pp. 1600-1611 ◽  
Author(s):  
Mark S Wipfli ◽  
John P Hudson ◽  
Dominic T Chaloner ◽  
John P Caouette
Keyword(s):  
Chlorophyll A ◽  
Pink Salmon ◽  
Dry Mass ◽  
Trophic Levels ◽  
Oncorhynchus Gorbuscha ◽  
Southeast Alaska ◽  
Natural Stream ◽  
Forest Stream ◽  
Natural Streams ◽  
Freshwater Salmon

We conducted this study to determine the relationship between salmon spawner abundance and stream biofilm and benthic macroinvertebrate abundance in Southeast Alaska. Experiments took place in outdoor artificial and natural streams. Six pink salmon (Oncorhynchus gorbuscha) carcass treatments (0.00, 1.45, 2.90, 4.35, 5.80, and 7.25 kg wet mass) placed in artificial channels were subsampled repeatedly for biofilm ash-free dry mass (AFDM), chlorophyll a, and macroinvertebrates. In a small (nonanadromous) forest stream, we sampled benthos throughout a 66-m reach 17 days after distributing 60 carcasses along the lower half of that reach. All response variables significantly increased in response to carcass additions in both artificial and natural streams. Chlorophyll a continued to increase across all loading rates, while AFDM and total macroinvertebrate densities showed no further response to loading beyond the first treatment (1.45 kg) in artificial streams. In the natural stream, AFDM and chironomid densities continued increasing across loading levels. These results indicated that increased spawner densities increased lower trophic level abundance until a trophic capacity was reached. Salmon escapement goals should consider food web effects, especially on trophic levels that support juvenile salmonids, that ultimately affect freshwater salmon production.

Genetic Aanalysis of Size in an Anadromous Population of Pink Salmon

1994 ◽  
Vol 51 (S1) ◽  
pp. 9-15 ◽  
Author(s):  
William W. Smoker ◽  
Anthony J. Gharrett ◽  
Michael S. Stekoll ◽  
John E. Joyce
Keyword(s):  
Variance Components ◽  
Genetic Basis ◽  
Pink Salmon ◽  
Oncorhynchus Gorbuscha ◽  
Southeast Alaska ◽  
Pink Salmon Oncorhynchus Gorbuscha ◽  
Factors Affecting ◽  
Phenotypic Correlations ◽  
Sib Families ◽  
Mature Fish

Variation of size, particularly among males, has a significant genetic basis in pink salmon (Oncorhynchus gorbuscha) in Auke Creek, southeast Alaska. Heritability (h2), based on variance components of 118 full sib − 59 paternal half sib families of mature fish tagged as fry with coded micro wires, are higher in males (h2 length: 0.8 ± 0.3 (mean ± SE); h2 weight: 0.6 ± 0.2, based on sire effect) than in females (h2 length: 0.3 ± 0.2; h2 weight: 0.4 ± 0.2). Realized heritability probably would be smaller because of environment variability between brood years in factors affecting size and growth. Estimates based on regression of offspring means on fathers' values are smaller (h2 length: 0.4 ± 0.1 in males; 0.2 ± 0.1 in females; h2 weight: 0.0 in males and 0.1 ± 0.1 in females). Estimates of genetic, environmental, and phenotypic correlations of length and weight are all >0.7 (SEs <0.1). Estimates of genetic correlation between length and day of migration from the sea are near 0.4 ± 0.2; estimates of environmental and phenotypic correlations between these traits are smaller (<0.2, SEs <0.1).

scholarly journals Relationship between salt use in fish farms and drift of macroinvertebrates in a freshwater stream

2020 ◽  
Vol 12 ◽  
pp. 205-213
Author(s):  
F Encina-Montoya ◽  
L Boyero ◽  
AM Tonin ◽  
M Fernanda Aguayo ◽  
C Esse ◽  
...  
Keyword(s):  
Fungal Infections ◽  
Fish Farm ◽  
Ecosystem Functions ◽  
Benthic Macroinvertebrate ◽  
Macroinvertebrate Communities ◽  
Fish Farms ◽  
Freshwater Biodiversity ◽  
Freshwater Stream ◽  
Stream Macroinvertebrate ◽  
And Control

In Chile, salt (NaCl) use per salmon fish farm ranges between 20-30 t yr-1 and is used to prevent and control fungal infections. An increase in salinity in freshwater can have adverse effects on freshwater biodiversity and ecosystem functions and services. We studied the effects of fish-farm effluents on benthic macroinvertebrate communities in a northern Patagonian stream (Chile). Benthic samples were collected at 3 sites near a land-based salmon aquaculture facility (one located 100 m upstream from the fish-farm outlet for effluent, 2 sites located 200 and 400 m downstream from the effluent source). We found changes in benthic macroinvertebrate communities downstream from the effluent, with higher abundances of tolerant taxa and lower abundances of sensitive taxa, which was related to nutrient and salt concentration in the water. We also studied the effects of salinity on macroinvertebrate drift in a mesocosm experiment conducted in recirculating channels, measuring the drift of 2 salt-sensitive macroinvertebrates (Andesiops peruvianus and Smicridea annulicornis), collected from an unpolluted northern Patagonian stream, after exposure to a range of salinity concentration pulses similar to those from fish farms. Our results demonstrate that (1) fish-farm effluent can alter stream macroinvertebrate community composition and dynamics, and (2) such effects are at least partly driven by high salt concentrations in effluent waters.

scholarly journals Gulls, Larus spp., Foraging at Pink Salmon, Oncorhynchus gorbuscha, Spawning Runs

2004 ◽  
Vol 118 (3) ◽  
pp. 442
Author(s):  
Mary F. Willson
Keyword(s):  
Body Size ◽  
Pink Salmon ◽  
Oncorhynchus Gorbuscha ◽  
Dominance Status ◽  
Southeast Alaska ◽  
Physical Strength ◽  
Salmon Eggs ◽  
Foraging Experience ◽  
Salmon Carcasses

Small and immature gulls foraged more often on drifting salmon eggs than did large and mature gulls, and large and mature gulls foraged more often on salmon carcasses, at streams in Southeast Alaska. These differences may be related to body size via physical strength and dominance status, as well as foraging experience.

A hierarchical Bayesian model for estimating historical salmon escapement and escapement timing

2001 ◽  
Vol 58 (8) ◽  
pp. 1648-1662 ◽  
Author(s):  
Zhenming Su ◽  
Milo D Adkison ◽  
Benjamin W Van Alen
Keyword(s):  
Count Data ◽  
Bayesian Model ◽  
Pink Salmon ◽  
Oncorhynchus Gorbuscha ◽  
Hierarchical Bayesian ◽  
Hierarchical Bayesian Model ◽  
Southeast Alaska ◽  
Pink Salmon Oncorhynchus Gorbuscha ◽  
Statistical Framework ◽  
Borrowing Strength

In this paper, we present an improved methodology for estimating salmon escapements from stream count data. The new method uses a hierarchical Bayesian model that improves estimates in years when data are sparse by "borrowing strength" from counts in other years. We present a model of escapement and of count data, a hierarchical Bayesian statistical framework, a Gibbs sampling approach for evaluation of the posterior distributions of the quantities of interest, and criteria for determining when the model and inference are adequate. We then apply the hierarchical Bayesian model to estimating historical escapement and escapement timing for pink salmon (Oncorhynchus gorbuscha) returns to Kadashan Creek in Southeast Alaska.

scholarly journals Effects of multiple stressors associated with agriculture on stream macroinvertebrate communities in a tropical catchment

PLoS ONE ◽  
2019 ◽  
Vol 14 (8) ◽  
pp. e0220528 ◽  
Author(s):  
Aydeé Cornejo ◽  
Alan M. Tonin ◽  
Brenda Checa ◽  
Ana Raquel Tuñon ◽  
Diana Pérez ◽  
...  
Keyword(s):  
Multiple Stressors ◽  
Macroinvertebrate Communities ◽  
Stream Macroinvertebrate
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