| Abstract: | Three morphotypes of lake trout Salvelinus namaycush are recognized in Lake Superior: lean, siscowet, and humper. Absolute morphotype assignment can be difficult. We used a size-free, whole-body morphometric analysis (truss protocol) to determine whether differences in body shape existed among lake trout morphotypes. Our results showed discrimination where traditional morphometric characters and meristic measurements failed to detect differences. Principal components analysis revealed some separation of all three morphotypes based on head and caudal peduncle shape, but it also indicated considerable overlap in score values. Humper lake trout have smaller caudal peduncle widths to head length and depth characters than do lean or siscowet lake trout. Lean lake trout had larger head measures to caudal widths, whereas siscowet had higher caudal peduncle to head measures. Backward stepwise discriminant function analysis retained two head measures, three midbody measures, and four caudal peduncle measures; correct classification rates when using these variables were 83% for leans, 80% for siscowets, and 83% for humpers, which suggests the measures we used for initial classification were consistent. Although clear ecological reasons for these differences are not readily apparent, patterns in misclassification rates may be consistent with evolutionary hypotheses for lake trout within the Laurentian Great Lakes. |
| Genre: | Article |
| ProdID: | 1000836 |
| Citation Author: | Moore, Seth A.; Bronte, Charles R. |
| Citation Contributing Office: | Great Lakes Science Center |
| Citation Datum: | |
| Citation Day: | |
| Citation Edition: | |
| Citation Editor: | |
| Citation End Page: | 1240 |
| Citation Issue: | 6 |
| Citation Keywords: | |
| Citation Language: | English |
| Citation Larger Work Title: | Transactions of the American Fisheries Society |
| Citation LatN: | |
| Citation LatS: | |
| Citation LonE: | |
| Citation LonW: | |
| Citation Month: | |
| Citation No Pagination: | |
| Citation Number Of Pages: | 7 |
| Citation Online Only Flag: | |
| Citation Phsyical Description: | p. 1233-1240 |
| Citation Projection: | |
| Citation Public Comments: | |
| Citation Publisher: | |
| Citation Series: | |
| Citation Series Code: | |
| Citation Series Number: | |
| Citation Search Results Text: | Delineation of sympatric morphotypes of lake trout in Lake Superior; 2001; Article; Journal; Transactions of the American Fisheries Society; Moore, Seth A.; Bronte, Charles R. |
| Citation Start Page: | 1233 |
| Citation Volume: | 130 |
| Citation Year: | 2001 |
| Type: | citation/reference |
| Text: | Delineation of sympatric morphotypes of lake trout in Lake Superior; 2001; Article; Journal; Transactions of the American Fisheries Society; Moore, Seth A.; Bronte, Charles R. |
| URL (THUMBNAIL): | http://pubs.er.usgs.gov/thumbnails/outside_thumb.jpg |
| Date Other: | Mon, 1 Jan 2001 00:00 -0600 |
| Publisher: | |
