scholarly journals Physical characteristics and simulated transport of pallid sturgeon and shovelnose sturgeon eggs

2020 ◽  
Vol 35 (1) ◽  
pp. 73-94
Author(s):  
Kimberly A. Chojnacki ◽  
Susannah O. Erwin ◽  
Amy E. George ◽  
James S. Candrl ◽  
Robert B. Jacobson ◽  
...  
Keyword(s):  
Physical Characteristics ◽  
Shovelnose Sturgeon ◽  
Pallid Sturgeon

Biology, Management, and Protection of North American Sturgeon

2002 ◽  
Keyword(s):  
Distinct Species ◽  
Current Status ◽  
Valid Species ◽  
Morphological Evidence ◽  
Morphometric Character ◽  
Meristic Characters ◽  
Shovelnose Sturgeon ◽  
Major Threat ◽  
Pallid Sturgeon ◽  
Two Indices

<em>Abstract.</em>—It is difficult to distinguish pallid sturgeon <em>Scaphirhynchus albus</em> from the morphologically similar, congeneric and sympatric shovelnose sturgeon <em>S. platorynchus</em>. This has led some to question whether the pallid sturgeon is indeed a valid species. Another controversy is whether the two species are hybridizing. Indices, based on various morphometric and meristic characters, have been proposed to discriminate among <em>Scaphirhynchus</em> taxa, but they are cumbersome to calculate in the field. We report two mathematical indices developed via multiple regression analysis that use five morphometric ratios and two meristics (Character Index), or the five morphometric ratios alone (Morphometric Character Index) as taxon predictors. Data from a study of pallid sturgeon and shovelnose sturgeon conducted by Carlson and Pflieger (1981) were used to develop the regression models. The consistency of identifications made by the two indices was examined using Discriminant Functions Analysis (DFA) on a collection of 257 <em>Scaphirhynchus</em> specimens from throughout the pallid sturgeon range. Specimens identified via the CI and mCI as pallid sturgeon grouped distinctly from the shovelnose sturgeon cluster; specimens identified as hybrids by the two indices formed an intermediate cluster. The majority (90% and 89.7%, respectively) of the specimens identified as pallid sturgeon by the Character Index (CI) and the Morphometric Character Index (mCI) were classified as pallid sturgeon by DFA. This morphological evidence supports the current status of pallid sturgeon and shovelnose sturgeon as distinct species. Interspecific hybridization, considered by some to be a major threat to the pallid sturgeon, appears to be common. The Pallid Sturgeon Recovery Team has recommended the CI for field identifications throughout the pallid sturgeon’s range.

scholarly journals Size-Dependent Trophic Patterns of Pallid Sturgeon and Shovelnose Sturgeon in a Large River System

2013 ◽  
Vol 4 (1) ◽  
pp. 41-52 ◽  
Author(s):  
William E. French ◽  
Brian D. S. Graeb ◽  
Katie N. Bertrand ◽  
Steven R. Chipps ◽  
Robert A. Klumb
Keyword(s):  
South Dakota ◽  
Trophic Position ◽  
Fork Length ◽  
Missouri River ◽  
River System ◽  
Large River ◽  
Diet Shift ◽  
Fish Prey ◽  
Shovelnose Sturgeon ◽  
Pallid Sturgeon

Abstract This study compared patterns of δ15N and δ13C enrichment of pallid sturgeon Scaphirhynchus albus and shovelnose sturgeon S. platorynchus in the Missouri River, United States, to infer their trophic position in a large river system. We examined enrichment and energy flow for pallid sturgeon in three segments of the Missouri River (Montana/North Dakota, Nebraska/South Dakota, and Nebraska/Iowa) and made comparisons between species in the two downstream segments (Nebraska/South Dakota and Nebraska/Iowa). Patterns in isotopic composition for pallid sturgeon were consistent with gut content analyses indicating an ontogenetic diet shift from invertebrates to fish prey at sizes of &gt;500-mm fork length (FL) in all three segments of the Missouri River. Isotopic patterns revealed shovelnose sturgeon did not experience an ontogenetic shift in diet and used similar prey resources as small (&lt;500-mm FL) pallid sturgeon in the two downstream segments. We found stable isotope analysis to be an effective tool for evaluating the trophic position of sturgeons within a large river food web.

Estimation of gonad volume, fecundity, and reproductive stage of shovelnose sturgeon using sonography and endoscopy with application to the endangered pallid sturgeon

2007 ◽  
Vol 23 (4) ◽  
pp. 411-419 ◽  
Author(s):  
By J. L. Bryan ◽  
M. L. Wildhaber ◽  
D. M. Papoulias ◽  
A. J. DeLonay ◽  
D. E. Tillitt ◽  
...  
Keyword(s):  
Reproductive Stage ◽  
Shovelnose Sturgeon ◽  
Pallid Sturgeon

scholarly journals Dietary assessment of age-0 pallid sturgeon and shovelnose sturgeon: implications for surrogacy

2019 ◽  
Vol 40 ◽  
pp. 321-327 ◽  
Author(s):  
NJC Gosch ◽  
TR Gemeinhardt ◽  
AP Civiello ◽  
AB Harrison ◽  
JL Bonneau
Keyword(s):  
Dietary Assessment ◽  
Shovelnose Sturgeon ◽  
Pallid Sturgeon

Habitat for Age-0 Shovelnose Sturgeon and Pallid Sturgeon in a Large River: Interactions among Abiotic Factors, Food, and Energy Intake

2012 ◽  
Vol 32 (1) ◽  
pp. 24-31 ◽  
Author(s):  
Dawn R. Sechler ◽  
Quinton E. Phelps ◽  
Sara J. Tripp ◽  
James E. Garvey ◽  
David P. Herzog ◽  
...  
Keyword(s):  
Energy Intake ◽  
Abiotic Factors ◽  
Large River ◽  
Shovelnose Sturgeon ◽  
Pallid Sturgeon

Gender identification of shovelnose sturgeon using ultrasonic and endoscopic imagery and the application of the method to the pallid sturgeon

2005 ◽  
Vol 67 (1) ◽  
pp. 114-132 ◽  
Author(s):  
M. L. Wildhaber ◽  
D. M. Papoulias ◽  
A. J. DeLonay ◽  
D. E. Tillitt ◽  
J. L. Bryan ◽  
...  
Keyword(s):  
Gender Identification ◽  
Shovelnose Sturgeon ◽  
Pallid Sturgeon
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