scholarly journals Estimates of roughness coefficients for selected natural stream channels with vegetated banks in New York

1995 ◽  
Author(s):  
William F. Coon
Keyword(s):  
New York ◽  
Stream Channels ◽  
Natural Stream

Failure of physiological metrics to predict dominance in juvenile Pacific salmon (Oncorhynchus spp.): habitat effects on the allometry of growth in dominance hierarchies1Order of authors represents their contribution to the manuscript.

2011 ◽  
Vol 68 (10) ◽  
pp. 1811-1818 ◽  
Author(s):  
Travis E. Van Leeuwen ◽  
Jordan S. Rosenfeld ◽  
Jeffrey G. Richards
Keyword(s):  
Dominance Hierarchy ◽  
Pacific Salmon ◽  
Interference Competition ◽  
Fish Growth ◽  
Stream Channels ◽  
Juvenile Salmonids ◽  
Natural Stream ◽  
Mixed Support ◽  
Juvenile Pacific Salmon ◽  
Access To Food

Territoriality is one of the best examples of interference competition and generally results in larger, dominant individuals gaining preferential access to food. However, the expectation of higher growth of dominant individuals among juvenile salmonids has received only mixed support. We used outdoor semi-natural stream channels stocked with varying sizes of young of the year juvenile salmonids under high and low food rations (i) to examine the mechanisms underlying variation in the benefits of dominance and (ii) to demonstrate that inconsistencies in the apparent benefits of dominance are a logical outcome of the allometry of growth and differential energy intake among fish of different size in a dominance hierarchy. Growth of dominants exceeded that of subordinates when food was abundant, but subordinates grew faster than dominants in low food treatments and when dominant fish increased in size and approached the capacity of their habitat. In general, size disparity within a dominance hierarchy may promote higher growth of subdominants because of the lower energetic requirements of smaller individuals, and the allometry of fish growth, relative to habitat capacity, can reverse the expected growth and condition of dominant and subordinate fish.

Intra- and inter-specific competition for winter concealment habitat in juvenile salmonids

2002 ◽  
Vol 59 (9) ◽  
pp. 1515-1523 ◽  
Author(s):  
A J Harwood ◽  
N B Metcalfe ◽  
S W Griffiths ◽  
J D Armstrong
Keyword(s):  
Salmo Salar ◽  
Salmo Trutta ◽  
Critical Importance ◽  
Foraging Habitat ◽  
Stream Channels ◽  
Refuge Use ◽  
Juvenile Salmonids ◽  
Natural Stream ◽  
Brown Trout Salmo Trutta ◽  
In The Wild

The availability of streambed refuges has previously been shown to be of critical importance to the survival of overwintering juvenile salmonids. We used semi-natural stream channels to quantify intra- and inter-specific competition for daytime refuges and the willingness of Atlantic salmon (Salmo salar) and brown trout (Salmo trutta) to share available shelter. Refuge use was frequently associated with aggressive behaviour when two fish were provided with only one shelter, with intra- and inter-specific competition being similar in intensity. Resident individuals were less likely to leave the refuge than were intruders, and sharing of refuges was uncommon, both when competing for one shelter (experiment I) and when these were provided in excess (experiment II). Fish showed greater preferences for foraging habitat during the night than for the location of daytime shelters and were therefore willing to shift habitats to find adequate shelter. Overall, these results suggest that winter competition for refuges, both within and between species of salmonid, is likely to be intense if refuge availability is limited in the wild.

Holocene Alluvial Stratigraphy in the Upper Susquehanna River Basin, New York

1981 ◽  
Vol 15 (3) ◽  
pp. 327-344 ◽  
Author(s):  
Richard W. Scully ◽  
Richard W. Arnold
Keyword(s):  
New York ◽  
Sandy Loam ◽  
New York State ◽  
Flood Plain ◽  
Vertical Accretion ◽  
Silt Loam ◽  
Stream Channels ◽  
Susquehanna River ◽  
Pollen Stratigraphy ◽  
South Central

AbstractTwo alluvial terraces and the present flood plain were studied at two locations along the Susquehanna and Unadilla Rivers in south-central New York state. They have formed since deglaciation and incision of the stream channels into the valley train deposits. The higher terrace has noncumulative soil profiles with well-developed color B horizons predominantly of silt loam and very fine sandy loam. The terrace is weathered to a degree similar to nearby glacial outwash terraces that have caps of similarly textured sediments. Incision that produced the terrace occurred before 9705 ± 130 yr B.P. The lower terrace is characterized by relatively thick, vertical-accretion deposits of silt loam that contain sequences of thin, buried A, color B, and C horizons. They were formed between about 3240 ± 110 (14C data of soil humin) and 235 ± 80 yr B.P. Deposits above the 235 ± 80 yr B.P. stratum are unweathered. The soil stratigraphy and 14C dates of soil humin from buried A horizons are surprisingly well correlated between sites. Most sediments of the present flood plain have been deposited since 1120 ± 80 yr B.P. Incipient A horizons and oxidation of inherited organic matter in the subsoil are the only evidence of pedogenesis in the flood-plain deposits that are older than 275 ± 80 yr B.P. The most recent flood-plain fill deposited since then is unaltered. These youngest sediments of the flood plain along with the youngest veneer of vertical-accretion deposits on the lowest terrace are associated with an increased rate of deposition largely attributable to clearing of the forests by settlers, beginning in the late 1700s. Comparison of the alluvial stratigraphy with the radiocarbon-dated pollen stratigraphy of southwestern New York (Miller 1973) reveals some apparent time correlations between alluvial events and vegetation changes. This gives reason to speculate that climatic change or forest catastrophes such as disease or drought are causes of some of the alluvial events.

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