Data from: Ecological release lead to novel otogenetic diet shift in kokanee (Oncoryhnchus nerka)

Main Authors: Shedd, Kyle R., von Hippel, Frank A., Willacker, James J., Hamon, Troy R., Schlei, Ora L., Wenburg, John K., Miller, Joe L., Pavey, Scott, A., Pavey, Scott A.
Format: info dataset Journal
Terbitan: , 2015
Subjects:
Online Access: https://zenodo.org/record/4999014
Daftar Isi:
  • We investigate adaptive resource polymorphism in kokanee (Oncorhynchus nerka) from Jo-Jo Lake, Alaska by determining whether previously observed niche expansion occurs at the population or individual level. Utilizing morphological, genetic, and stable isotope techniques, we found no evidence of discrete trophic morphotypes as previously described, but instead found evidence for an ontogenetic diet shift. Carbon and nitrogen isotope data indicate a 40% decrease in the proportion of benthic feeding and an increase of 1 trophic position over the size and age ranges of adult kokanee, corresponding to a diet shift from consumption of macroinvertebrates in smaller individuals to piscivory in larger individuals. This novel piscivory in kokanee may result from predatory and competitive freedom resulting from the lack of limnetic predators in Jo-Jo Lake. Piscivorous feeding despite a phenotype-environment mismatch has resulted in large, piscivorous kokanee having up to 70% of their gill rakers damaged. Observed reductions in gill raker number relative to the putative ancestral population are convergent with expectations for piscivorous fishes, despite a presumed lack of standing genetic variation for piscivory in the sockeye salmon-kokanee species complex. Jo-Jo Lake kokanee are a distinctive example of adaptation in salmonids in response to ecological release. This unusual population highlights the importance of phenotypic plasticity in response to competition in shaping the adaptive landscape and altering evolutionary trajectories.
  • Shedd_et_al_2015_GenepopThis is the Genepop file for "Ecological release lead to novel otogenetic diet shift in kokanee (Oncoryhnchus nerka)". The file contains 482 individuals genotyped at 14 microsatellite loci. The name of each sample includes the putative diet class based on stomach content analysis (Nonpiscivore, Piscivore, and Unknown), the year collected, and the individual identification number(s).Shedd_et_al_2015_StableIsotopeThis file contains carbon and nitrogen stable isotope data for all aquatic samples analyzed in this study. Note that only samples collected in 2011 where analyzed for stable isotopes.Shedd_et_al_2015_StomachContentsThis file contains the % of total weight stomach content data for the 64 kokanee stomachs collected in 2011. Column headings for each diet category are found in the caption for Figure 1.Shedd_et_al_2015_GillRakerThis file contains gill raker data for 161 kokanee.Shedd_et_al_2015_GeometricMorphometricsThis file contains geometric morphometric data on the relative warps for 124 kokanee.