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Jared Joseph Homola

Publications and source records attributed to Jared Joseph Homola.

6 recordsLinked to original sources

Optimization of wetland environmental DNA metabarcoding protocols for Great Lakes region herpetofauna

Many species of reptiles and amphibians (herpetofauna) rely on wetlands that are being degraded and lost at a high rate. Characterization of herpetofauna diversity in different wetland types may help guide conservation strategies. However, traditional survey methods often involve sampling within small temporal windows, and the gear deployed may be taxonomically biased, thus, they may fail to accurately characterize species presence/absence and diversity. In contrast, environmental (e)DNA metabarcoding has been shown to effectively survey entire aquatic communities and can provide a useful complement to traditional surveys. The objective of this study was to design and optimize eDNA sampling and laboratory protocols for wetland herpetofauna. Protocols evaluated included different water sampling approaches (point versus transect sampling), seasonality of sampling, and choice of metabarcoding marker (mitochondrial 12S versus 16S rDNA). Samples collected from 10 sites across southern Michigan detected 17 amphibian and five reptile species, including four species of conservation concern ( Ambystoma texanum , Clemmys guttata , Rana palustris , and Sternotherus odoratus ). We observed no difference in the number of species detected between point and transect samples ( p = 0.70), but point sampling required less time ( p = 0.03) and allowed significantly larger volumes of water to be filtered ( p = 1.13e-5). No difference in species richness was observed between the 12S and 16S mitochondrial DNA markers ( p = 0.96). However, a greater number of taxa were identifiable at the species level when using the 16S locus. There was also a significant difference in the number of species detected between early and late summer sampling periods (more species detected in the earlier period; p = 6.31e-6), and some species were only found in the early or late sampling period. Sampling during multiple periods to fully characterize species composition, the use of point sampling, and the 16S mtDNA marker for herpetofauna eDNA metabarcoding studies may increase efficiency and reliability of results.

Environmental DNA

Genomic data characterize reproductive ecology patterns in Michigan invasive Red Swamp Crayfish (Procambarus clarkii)

The establishment and spread of invasive species are directly related to intersexual interactions as dispersal and reproductive success are related to distribution, effective population size, and population growth. Accordingly, populations established by r-selected species are particularly difficult to suppress or eradicate. One such species, the red swamp crayfish ( Procambarus clarkii ) is established globally at considerable ecological and financial costs to natural and human communities. Here, we develop a single nucleotide polymorphism (SNP) loci panel for P. clarkii using restriction-associated DNA-sequencing data. We use the SNP panel to successfully genotype 1800 individuals at 930 SNPs in southeastern Michigan, USA. Genotypic data were used to reconstruct pedigrees, which enabled the characterization of P. clarkii's mating system and statistical tests for associations among environmental, demographic, and phenotypic predictors and adult reproductive success estimates. We identified juvenile cohorts using genotype-based pedigrees, body size, and sampling timing, which elucidated the breeding phenology of multiple introduced populations. We report a high prevalence of multiple paternity in each surveyed waterbody, indicating polyandry in this species. We highlight the use of newly developed rapid genomic assessment tools for monitoring population reproductive responses, effective population sizes, and dispersal during ongoing control efforts.

Evolutionary Applications

Demographic patterns of walleye (Sander vitreus) reproductive success in a Wisconsin population

Harvest in walleye Sander vitreus fisheries is size-selective and could influence phenotypic traits of spawners; however, contributions of individual spawners to recruitment are unknown. We used parentage analyses using single nucleotide polymorphisms to test whether parental traits were related to the probability of offspring survival in Escanaba Lake, Wisconsin. From 2017 to 2020, 1339 adults and 1138 juveniles were genotyped and 66% of the offspring were assigned to at least one parent. Logistic regression indicated the probability of reproductive success (survival of age-0 to first fall) was positively (but weakly) related to total length and growth rate in females, but not age. No traits analyzed were related to reproductive success for males. Our analysis identified the model with the predictors' growth rate and year for females and the models with year and age and year for males as the most likely models to explain variation in reproductive success. Our findings indicate that interannual variation (i.e., environmental conditions) likely plays a key role in determining the probability of reproductive success in this population and provide limited support that female age, length, and growth rate influence recruitment.

Wisconsin

An amplicon genotyping panel suitable for species identification and population genetics in sauger (Sander canadensis) and walleye (Sander vitreus)

Sauger ( Sander canadensis ) and walleye ( Sander vitreus ) are closely related North American fish species that are often managed by fishery agencies throughout their ranges. However, genotyping resources for sauger are presently limited to a small set of microsatellite loci. We evaluated whether primers in an existing walleye genotyping-in-thousands panel could amplify single nucleotide polymorphism loci (SNPs) in sauger. We identified 71 primer pairs that amplify 118 SNPs in both species. Allele frequency differences were large enough to confidently distinguish the species and identify hybrids. Additionally, we identified 41 loci with observed heterozygosity > 0.1 in sauger; these markers may be useful for simple population genetic analyses and parentage analysis when few contributors are present and for differentiating highly structured populations.

Minnesota, Wisconsin

High-density genomic data reveal fine-scale population structure and pronounced islands of adaptive divergence in lake whitefish (Coregonus clupeaformis) from Lake Michigan

Understanding patterns of genetic structure and adaptive variation in natural populations is crucial for informing conservation and management. Past genetic research using 11 microsatellite loci identified six genetic stocks of lake whitefish ( Coregonus clupeaformis ) within Lake Michigan, USA. However, ambiguity in genetic stock assignments suggested those neutral microsatellite markers did not provide adequate power for delineating lake whitefish stocks in this system, prompting calls for a genomics approach to investigate stock structure. Here, we generated a dense genomic dataset to characterize population structure and investigate patterns of neutral and adaptive genetic diversity among lake whitefish populations in Lake Michigan. Using Rapture sequencing, we genotyped 829 individuals collected from 17 baseline populations at 197,588 SNP markers after quality filtering. Although the overall pattern of genetic structure was similar to the previous microsatellite study, our genomic data provided several novel insights. Our results indicated a large genetic break between the northwestern and eastern sides of Lake Michigan, and we found a much greater level of population structure on the eastern side compared to the northwestern side. Collectively, we observed five genomic islands of adaptive divergence on five different chromosomes. Each island displayed a different pattern of population structure, suggesting that combinations of genotypes at these adaptive regions are facilitating local adaptation to spatially heterogenous selection pressures. Additionally, we identified a large linkage disequilibrium block of ~8.5 Mb on chromosome 20 that is suggestive of a putative inversion but with a low frequency of the minor haplotype. Our study provides a comprehensive assessment of population structure and adaptive variation that can help inform the management of Lake Michigan's lake whitefish fishery and highlights the utility of incorporating adaptive loci into fisheries management.

Michigan, Wisconsin

Resist-accept-direct (RAD) considerations for climate change adaptation in fisheries: The Wisconsin experience

Decision-makers in inland fisheries management must balance ecologically and socially palatable objectives for ecosystem services within financial or physical constraints. Climate change has transformed the potential range of ecosystem services available. The Resist-Accept-Direct (RAD) framework offers a foundation for responding to climate-induced ecosystem modification; however, ecosystem trajectories and current practices must be understood to improve future decisions. Using Wisconsin's diverse inland fisheries as a case study, management strategies for recreational and subsistence fisheries in response to climate change were reviewed within the RAD framework. Current strategies largely focus on resist actions, while future strategies may need to shift toward accept or direct actions. A participatory adaptive management framework and co-production of policies between state and tribal agencies could prioritise lakes for appropriate management action, with the goal of providing a landscape of diverse fishing opportunities. This knowledge co-production represents a process of social learning requiring substantial investments of funding and time.

Wisconsin