Suppression of Cannibalism during Larviculture of Burbot through Size Grading
The survival and percentage of North American Burbot Lotalota maculosa larvae andmetamorphosing larvae presumed to havebeen cannibalized during a 15-d period immediately following asize-grading event were compared with those of fish in nongradedcontrol groups. In larvae (mean TL, 11.8 mm), grading i...
| Published in: | North American Journal of Aquaculture |
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| Main Authors: | , , , , |
| Format: | Article in Journal/Newspaper |
| Language: | English |
| Published: |
Amer Fisheries Soc
2013
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| Subjects: | |
| Online Access: | https://doi.org/10.1080/15222055.2013.829146 http://ecite.utas.edu.au/88784 |
| Summary: | The survival and percentage of North American Burbot Lotalota maculosa larvae andmetamorphosing larvae presumed to havebeen cannibalized during a 15-d period immediately following asize-grading event were compared with those of fish in nongradedcontrol groups. In larvae (mean TL, 11.8 mm), grading immediatelyproduced a size distinction, as the group that passed thegrader was significantly narrower and shorter than the group retainedby the grader. Themean coefficient of variation of the lengthof larvae in the retained group was significantly lower than that ofthe control group, indicating that grading reduced size heterogeneity.Grading significantly increased larval survival, which averaged74.3% and 93.3% for the passed and retained fish, respectively,compared with 59.3% in the control. Increased survival was linkedto a reduction in the percentage of larvae presumed cannibalized inthe graded groups. Inmetamorphosing larvae (mean TL, 21.0 mm),grading did not significantly change TL, width, or the coefficientof variation of length, nor did it improve survival or reduce presumedcannibalism. This study provides initial empirical evidencethat size grading can be an effective way to significantly reducecannibalism when done at the onset of cannibalism in larval-stageBurbot. |
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