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John D. Robinson

Publications and source records attributed to John D. Robinson.

8 recordsLinked to original sources

A framework for estimating age and growth using sibship relationships inferred from genomic data

Pedigree reconstruction based on genomic data offers a novel approach for estimating age and growth in wild populations. However, frameworks that use reconstructed pedigrees to parameterize growth models have not been available. We developed a sibship age and growth framework and evaluated the approach using simulation and an empirical application to Sea Lamprey ( Petromyzon marinus ) age and growth analysis. Simulation research revealed that the framework may be widely applicable to semelparous fishes. Applicability to iteroparous fishes was constrained to scenarios in which the percentage of multi-age sibling groups was low. Age assignment using the framework was unbiased for sibling groups first captured at younger ages. Age assignment for sibling groups first captured at older ages (after growth rate had substantially slowed) was biased low due to the hierarchal approach that we adopted to estimate sibling group age-at-first capture. However, this did not result in biased growth parameter estimates. Model output allowed for identification of unreliable age assignments. Finally, the empirical application provided evidence that the framework could address knowledge gaps that have been challenging to address with established age and growth methods.

Canadian Journal of Fisheries and Aquatic Sciences↗

DNA retention in sea lamprey digestive tracts: Insights from controlled feeding experiments

The sea lamprey ( Petromyzon marinus ), a non-native species in the Laurentian Great Lakes, has significantly impacted native fish communities and commercial fisheries, requiring population suppression efforts. While traditional control methods such as lampricides and barriers have reduced sea lamprey population abundance, questions remain regarding sea lamprey dietary composition given the focus of current damage assessments on economically and ecologically important host species. Recent advances in molecular technology offer promising methods of sea lamprey dietary assessment. Specifically, DNA metabarcoding enables species-specific identification of taxonomically diverse prey items from gut and fecal samples, and has proven effective in many taxa, including hematophagous species such as Arctic lamprey ( Lethenteron camtschaticum ) and sea lamprey. However, studies on DNA retention within digestive tracts are limited, particularly given the potential effects of environmental and dietary factors among hematophagous species. We used controlled feeding experiments to understand the effects these factors may have on DNA retention and host detectability within sea lamprey digestive tracts. Additionally, we evaluated the utility of metabarcoding for identifying multiple host species from consecutive feedings. Results indicate that host DNA can be detected up to 30 days post-feeding, with detection probability decreasing with increasing time following feeding. Temperature effects were dependent upon fasting periods, and host-switching trials indicated multiple previous host species could be detected from a single lamprey. Findings provide valuable insights for refining dietary analysis protocols for wild-caught sea lamprey within native and introduced ranges.

Environmental DNA↗

Competition between invasive round goby and native slimy sculpin in a coldwater laboratory setting

Slimy sculpin ( Cottus cognatus ) abundance has substantially declined in many regions of the Laurentian Great Lakes coincident with the arrival and range expansions of invasive round goby ( Neogobius melanostomus ). Previous studies have shown that round goby can outcompete native mottled sculpin ( C. bairdii ) for shelter and negatively affect native spoonhead sculpin ( C. ricei ) growth, but direct behavioral interactions of slimy sculpin and round goby have not been observed. We conducted a laboratory experiment in which a pair of slimy sculpin were placed in an aquarium that contained an artificial spawning shelter and one round goby (treatment, n = 10) or no other fish (control, n = 10) for at least 30 days at temperatures reflective of their potential offshore overlap. We measured slimy sculpin egg deposition, aggressive interactions, artificial shelter occupancy, growth, and survival. Slimy sculpin were less likely to occupy shelters and experienced increased intraspecific competition when a round goby was present. In contrast, round goby rarely chased slimy sculpin, slimy sculpin were more likely to chase round goby, and slimy sculpin growth, egg deposition, and survival were not significantly different between groups. Differences in density between treatments and the relative size of fish could confound our observations. However, the dominant slimy sculpin occupied the shelter at similar rates between experimental groups if the round goby was smaller. Our results indicate that larger round goby overlapping with slimy sculpin could affect slimy sculpin shelter and space use, but the Great Lakes environment may create more stress for slimy sculpin than we observed.

Lake Michigan, Lake Superior↗

Development of PCR blocking primers enabling DNA metabarcoding analysis of dietary composition in hematophagous sea lamprey

Conventional dietary assessments are challenging in hematophagous species, particularly in sea lamprey ( Petromyzon marinus ). However, recent technological developments and molecular approaches have provided an attractive alternative through the use of DNA metabarcoding. While DNA metabarcoding has been used for dietary analyses in numerous species, including lampreys, applications of universal primers that detect a diverse set of prey items can be limited by the amplification of predator DNA. In this study, we designed and tested eight blocking primers designed to suppress the amplification of sea lamprey DNA with vertebrate-universal primers targeting the mitochondrial 12S rRNA gene. This approach allowed for the use of a single marker to amplify a taxonomically diverse suite of host species, in contrast to previous studies that used multiple taxon-specific primer pairs (e.g., Salmonidae, Cyprinidae, and Catostomidae). Candidate blocking primers evaluated in this study differed in base pair length, end sequence modification, and purification method. Samples with different sea lamprey-to-host DNA ratios were subjected to multiple detection methods including gel electrophoresis, quantitative PCR, and DNA metabarcoding to assess the ability of each blocking primer to selectively suppress amplification of the sea lamprey 12S gene region. All blocking primers tested performed well and demonstrated high effectiveness, suppressing sea lamprey reads by > 99.9% in mock communities and improving host DNA sequence recovery across various sample types, including wild-caught lamprey. Results show that the blocking primers evaluated can facilitate molecular diet analysis in sea lamprey, allowing the amplification of a taxonomically diverse range of host fish species with universal primers.

Great Lakes↗

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↗

Assessing grass carp (Ctenopharyngodon idella) occupancy and detection probability within Lake Erie from environmental DNA

Grass carp ( Ctenopharyngodon idella ), an invasive cyprinid within the Laurentian Great Lakes, is naturally reproducing in several Lake Erie tributaries, which has raised concerns of the species’ spread throughout Lake Erie and the other Great Lakes. Knowledge of the recent invasion extent outside of the western basin of Lake Erie, particularly in eastern tributaries and nearshore waters, is limited. Understanding the invasion extent would improve the efficacy of ongoing coordinated multi-agency control efforts. Molecular tools, such as environmental DNA (eDNA), have shown promise for early detection of aquatic invasive species. In this study, water samples (N = 476) were collected for grass carp eDNA monthly between May and November in 2018 and 2019, at three sites in the Michigan waters of Lake Erie and the Detroit River. We fit Bayesian multi-scale occupancy models to determine differences in eDNA capture and detection probability among grass carp qPCR assays, sampling sites, and across time. To determine whether grass carp were physically present, and to validate eDNA samples, we quantified recent grass carp presence in sampled areas using an existing acoustic telemetry and field sampling framework. Our results indicate that grass carp eDNA capture probability differed among sites, but there was no difference among months. Positive grass carp eDNA detections were observed across multiple months at each site, with 69% of site-specific sampling events testing positive for grass carp eDNA on at least one assay and replicate. The majority (65%) of weeks where positive eDNA sampling detections occurred also concurrently had one or more grass carp detected via acoustic telemetry 1–6 days prior. Our results highlight the potential utility of using eDNA to monitor the invasion extent of grass carp within the nearshore waters of Lake Erie. However, further evaluation of the factors that influence grass carp eDNA characteristics among sites within Lake Erie are needed to determine its efficacy for surveillance protocols by natural resource management agencies.

Lake Erie↗

Pedigree analysis and estimates of effective breeding size characterize sea lamprey reproductive biology

The sea lamprey ( Petromyzon marinus ) is an invasive species in the Great Lakes and the focus of a large control and assessment program. Current assessment methods provide information on the census size of spawning adult sea lamprey in a small number of streams, but information characterizing reproductive success of spawning adults is rarely available. We used RAD-capture sequencing to genotype single nucleotide polymorphism (SNP) loci for ~1600 sea lamprey larvae collected from three streams in northern Michigan (Black Mallard, Pigeon, and Ocqueoc Rivers). Larval genotypes were used to reconstruct family pedigrees, which were combined with Gaussian mixture analyses to identify larval age classes for estimation of spawning population size. Two complementary estimates of effective breeding size ( N b ), as well as the extrapolated minimum number of spawners ( N s ), were also generated for each cohort. Reconstructed pedigrees highlighted inaccuracies of cohort assignments from traditionally used mixture analyses. However, combining genotype-based pedigree information with length-at-age assignment of cohort membership greatly improved cohort identification accuracy. Population estimates across all three streams sampled in this study indicate a small number of successfully spawning adults when barriers were in operation, implying that barriers limited adult spawning numbers but were not completely effective at blocking access to spawning habitats. Thus, the large numbers of larvae present in sampled systems were a poor indicator of spawning adult abundance. Overall, pedigree-based N b and N s estimates provide a promising and rapid assessment tool for sea lamprey and other species.

Michigan↗