2020
Kelson, Suzanne J.; Power, Mary E.; Finlay, Jacques C.; Carlson, Stephanie M.
Partial migration alters population ecology and food chain length: evidence from a salmonid fish Journal Article
In: Ecosphere, vol. 11, no. 2, pp. e03044, 2020.
Abstract | Links | BibTeX | Tags: eco-evolutionary dynamics, ERCZO, extended phenotype, food chain length, intraspecific variation, life history, O. mykiss, Oncorhynchus mykiss, partial migration, population ecology, size structure, steelhead/rainbow trout
@article{Kelson2020b,
title = {Partial migration alters population ecology and food chain length: evidence from a salmonid fish},
author = {Suzanne J. Kelson and Mary E. Power and Jacques C. Finlay and Stephanie M. Carlson},
url = {https://angelo.berkeley.edu/wp-content/uploads/sites/59/ecs2.3044.pdf},
doi = {10.1002/ecs2.3044},
year = {2020},
date = {2020-02-21},
journal = {Ecosphere},
volume = {11},
number = {2},
pages = {e03044},
abstract = {Many migratory species, from monarch butterflies to wildebeest, express partial migration, where only a subset of a population migrates. This intraspecific variation is likely to have large ecological consequences. We studied the ecological consequences of partial migration in a salmonid fish, Oncorhynchus mykiss, in coastal streams in California, USA. One ecotype, steelhead trout, migrates to the ocean, whereas the other, rainbow trout, completes its lifecycle in freshwater. Migration has a strong genetic basis in O. mykiss. In one stream, we found differences in the frequency of migration‐linked genotypes below and above a waterfall barrier (migratory allele frequency of 60% below vs. 31% above). Below the waterfall, in the migratory‐dominated region, the density of young fish (<1 yr old) was approximately twice that in the resident‐dominated region above the waterfall (0.46 vs. 0.26 individuals/m2, respectively), presumably reflecting the higher fecundity of migratory females. Additionally, there were half as many older fish (>1 yr old) in pools downstream of the waterfall (0.05 vs. 0.13 individuals/m2). In a second stream, between‐year variation in the dominance of migratory vs. resident fish allowed us to explore differences in fish density and size structure through time, and we found a consistent pattern. In brief, when migratory genotypes dominated, we found higher densities of young fish and lower densities of older fish, resulting in a simpler size structure, compared to when resident genotypes dominated. Moreover, large resident trout had a slightly higher trophic position than young fish (3.92 vs. 3.42 in one creek and 3.77 vs. 3.17 in the other), quantified with stable isotope data. The difference in fish size structure did not generate trophic cascades. Partial migration is widespread among migratory populations, as is phenotypic divergence between resident and migratory forms, suggesting the potential for widespread ecological effects arising from this common form of intraspecific variation.},
keywords = {eco-evolutionary dynamics, ERCZO, extended phenotype, food chain length, intraspecific variation, life history, O. mykiss, Oncorhynchus mykiss, partial migration, population ecology, size structure, steelhead/rainbow trout},
pubstate = {published},
tppubtype = {article}
}
Many migratory species, from monarch butterflies to wildebeest, express partial migration, where only a subset of a population migrates. This intraspecific variation is likely to have large ecological consequences. We studied the ecological consequences of partial migration in a salmonid fish, Oncorhynchus mykiss, in coastal streams in California, USA. One ecotype, steelhead trout, migrates to the ocean, whereas the other, rainbow trout, completes its lifecycle in freshwater. Migration has a strong genetic basis in O. mykiss. In one stream, we found differences in the frequency of migration‐linked genotypes below and above a waterfall barrier (migratory allele frequency of 60% below vs. 31% above). Below the waterfall, in the migratory‐dominated region, the density of young fish (<1 yr old) was approximately twice that in the resident‐dominated region above the waterfall (0.46 vs. 0.26 individuals/m2, respectively), presumably reflecting the higher fecundity of migratory females. Additionally, there were half as many older fish (>1 yr old) in pools downstream of the waterfall (0.05 vs. 0.13 individuals/m2). In a second stream, between‐year variation in the dominance of migratory vs. resident fish allowed us to explore differences in fish density and size structure through time, and we found a consistent pattern. In brief, when migratory genotypes dominated, we found higher densities of young fish and lower densities of older fish, resulting in a simpler size structure, compared to when resident genotypes dominated. Moreover, large resident trout had a slightly higher trophic position than young fish (3.92 vs. 3.42 in one creek and 3.77 vs. 3.17 in the other), quantified with stable isotope data. The difference in fish size structure did not generate trophic cascades. Partial migration is widespread among migratory populations, as is phenotypic divergence between resident and migratory forms, suggesting the potential for widespread ecological effects arising from this common form of intraspecific variation.
Kelson, Suzanne J.; Miller, Michael R.; Thompson, Tasha Q.; O’Rourke, Sean M.; Carlson, Stephanie M.
Temporal dynamics of migration‐linked genetic variation are driven by streamflows and riverscape permeability Journal Article
In: Molecular Ecology, vol. 29, no. 5, pp. 870-885, 2020.
Abstract | Links | BibTeX | Tags: ecology, ERCZO, genetic variation, landscape genetics, life history, O. mykiss, Oncorhynchus mykiss, partial barrier, partial migration, river networks
@article{Kelson2020,
title = {Temporal dynamics of migration‐linked genetic variation are driven by streamflows and riverscape permeability},
author = {Suzanne J. Kelson and Michael R. Miller and Tasha Q. Thompson and Sean M. O'Rourke and Stephanie M. Carlson},
url = {https://angelo.berkeley.edu/wp-content/uploads/sites/59/mec.15367-1.pdf},
doi = {10.1111/mec.15367},
year = {2020},
date = {2020-02-03},
journal = {Molecular Ecology},
volume = {29},
number = {5},
pages = {870-885},
abstract = {Landscape permeability is often explored spatially, but may also vary temporally. Landscape permeability, including partial barriers, influences migratory animals that move across the landscape. Partial barriers are common in rivers where barrier passage varies with streamflow. We explore the influence of partial barriers on the spatial and temporal distribution of migration‐linked genotypes of Oncorhynchus mykiss, a salmonid fish with co‐occurring resident and migratory forms, in tributaries to the South Fork Eel River, California, USA, Elder and Fox Creeks. We genotyped >4,000 individuals using RAD‐capture and classified individuals as resident, heterozygous or migratory genotypes using life history‐associated loci. Across four years of study (2014–2017), the permeability of partial barriers varied across dry and wet years. In Elder Creek, the largest waterfall was passable for adults migrating up‐river 4–39 days each year. In this stream, the overall spatial pattern, with fewer migratory genotypes above the waterfall, remained true across dry and wet years (67%–76% of migratory alleles were downstream of the waterfall). We also observed a strong relationship between distance upstream and proportion of migratory alleles. In Fox Creek, the primary barrier is at the mouth, and we found that the migratory allele frequency varied with the annual timing of high flow events. In years when rain events occurred during the peak breeding season, migratory allele frequency was high (60%–68%), but otherwise it was low (30% in two years). We highlight that partial barriers and landscape permeability can be temporally dynamic, and this effect can be observed through changing genotype frequencies in migratory animals.},
keywords = {ecology, ERCZO, genetic variation, landscape genetics, life history, O. mykiss, Oncorhynchus mykiss, partial barrier, partial migration, river networks},
pubstate = {published},
tppubtype = {article}
}
Landscape permeability is often explored spatially, but may also vary temporally. Landscape permeability, including partial barriers, influences migratory animals that move across the landscape. Partial barriers are common in rivers where barrier passage varies with streamflow. We explore the influence of partial barriers on the spatial and temporal distribution of migration‐linked genotypes of Oncorhynchus mykiss, a salmonid fish with co‐occurring resident and migratory forms, in tributaries to the South Fork Eel River, California, USA, Elder and Fox Creeks. We genotyped >4,000 individuals using RAD‐capture and classified individuals as resident, heterozygous or migratory genotypes using life history‐associated loci. Across four years of study (2014–2017), the permeability of partial barriers varied across dry and wet years. In Elder Creek, the largest waterfall was passable for adults migrating up‐river 4–39 days each year. In this stream, the overall spatial pattern, with fewer migratory genotypes above the waterfall, remained true across dry and wet years (67%–76% of migratory alleles were downstream of the waterfall). We also observed a strong relationship between distance upstream and proportion of migratory alleles. In Fox Creek, the primary barrier is at the mouth, and we found that the migratory allele frequency varied with the annual timing of high flow events. In years when rain events occurred during the peak breeding season, migratory allele frequency was high (60%–68%), but otherwise it was low (30% in two years). We highlight that partial barriers and landscape permeability can be temporally dynamic, and this effect can be observed through changing genotype frequencies in migratory animals.
2019
Kelson, Suzanne J.; Miller, Michael R.; Thompson, Tasha Q.; O’Rourke, Sean M.; Carlson, Stephanie M.
Do genomics and sex predict migration in a partially migratory salmonid fish, Oncorhynchus mykiss? Journal Article
In: Canadian Journal of Fisheries and Aquatic Sciences, vol. 76, no. 11, pp. 2080-2088, 2019.
Abstract | Links | BibTeX | Tags: ERCZO, genetic variation, O. mykiss, partial migration
@article{Kelson2019b,
title = {Do genomics and sex predict migration in a partially migratory salmonid fish, Oncorhynchus mykiss?},
author = {Suzanne J. Kelson and Michael R. Miller and Tasha Q. Thompson and Sean M. O'Rourke and Stephanie M. Carlson},
url = {https://angelo.berkeley.edu/wp-content/uploads/sites/59/cjfas-2018-0394-1.pdf},
doi = {10.1139/cjfas-2018-0394},
year = {2019},
date = {2019-02-14},
journal = {Canadian Journal of Fisheries and Aquatic Sciences},
volume = {76},
number = {11},
pages = {2080-2088},
abstract = {Partial migration is a common phenomenon wherein populations include migratory and resident individuals. Whether an individual migrates or not has important ecological and management implications, particularly within protected populations. Within partially migratory populations of Oncorhynchus mykiss, migration is highly correlated with a specific genomic region, but it is unclear how well this region predicts migration at the individual level. Here, we relate sex and life history genotype, determined using >400 single nucleotide polymorphisms (SNPs) on the migratory-linked genomic region, to life history expression of marked juvenile O. mykiss from two tributaries to the South Fork Eel River, northern California. Most resident fish were resident genotypes (57% resident, 37% heterozygous, 6% migratory genotype) and male (78%). Most migratory fish were female (62%), but were a mixture of genotypes (30% resident, 45% heterozygous, 25% migratory genotype). Sex was more strongly correlated with life history expression than genotype, but the best-supported model included both. Resident genotypes regularly migrated, highlighting the importance of conserving the full suite of life history and genetic diversity in partially migratory populations.},
keywords = {ERCZO, genetic variation, O. mykiss, partial migration},
pubstate = {published},
tppubtype = {article}
}
Partial migration is a common phenomenon wherein populations include migratory and resident individuals. Whether an individual migrates or not has important ecological and management implications, particularly within protected populations. Within partially migratory populations of Oncorhynchus mykiss, migration is highly correlated with a specific genomic region, but it is unclear how well this region predicts migration at the individual level. Here, we relate sex and life history genotype, determined using >400 single nucleotide polymorphisms (SNPs) on the migratory-linked genomic region, to life history expression of marked juvenile O. mykiss from two tributaries to the South Fork Eel River, northern California. Most resident fish were resident genotypes (57% resident, 37% heterozygous, 6% migratory genotype) and male (78%). Most migratory fish were female (62%), but were a mixture of genotypes (30% resident, 45% heterozygous, 25% migratory genotype). Sex was more strongly correlated with life history expression than genotype, but the best-supported model included both. Resident genotypes regularly migrated, highlighting the importance of conserving the full suite of life history and genetic diversity in partially migratory populations.