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The number of non-parasitic (brook) lamprey species in the genus Lampetra is underestimated since isolated populations are generally considered one species due to their relatively conserved body form. The phylogeographic and phylogenetic structure was estimated among and within Lampetra species along the Pacific coast of North America (presumed to represent Lampetra richardsoni; L. pacifica – which is currently regarded as a junior synonym of L. richardsoni; L. ayresii; and L. hubbsi) using up to three mitochondrial and three nuclear genetic markers. These data show that L. richardsoni as currently recognized is polyphyletic when lampreys (some of which show up to 8 K2P% sequence divergence) from Siuslaw River and...
Suction dredge mining can can affect all life stages of freshwater mussels. Mussels are harmed directly through physical injury or mortality, interference with reproduction and feeding, and inability to excavate themselves and/or regain a natural orientation in the substrate after being entrained and covered by tailings; and indirectly through habitat loss and water quality degradation. The damage to substrate used by mussels can last more than one season. These direct and indirect effects are likely to reduce the size and resiliency of freshwater mussel populations.
Abstract Environmental DNA (eDNA) from aquatic vertebrates has recently been used to estimate the presence of a species. We hypothesized that fish release DNA into the water at a rate commensurate with their biomass. Thus, the concentration of eDNA of a target species may be used to estimate the species biomass. We developed an eDNA method to estimate the biomass of common carp (Cyprinus carpio L.) using laboratory and field experiments. In the aquarium, the concentration of eDNA changed initially, but reached an equilibrium after 6 days. Temperature had no effect on eDNA concentrations in aquaria. The concentration of eDNA was positively correlated with carp biomass in both aquaria and experimental ponds. We used...
Southern brook lamprey larvae, Zchthyomyzon gagei, were collected from four creeks in Alabama and Mississippi. Larvae abundance (number m-‘) and length (mm) were measured over a range of sites to quantify some of the physical parameters involved in larval habitat selection. Particle size distribution, hydraulic conductivity, porosity and organic content were the factors analyzed. Abundance of larvae was greatest when particles smaller than 0.15 mm and 1.0-2.0 mm in diameter represented at least 40% and 8% dry weight of the substrate, respectively. Abundance of larvae was lowest when the small particles represented less than 10% dry weight of the substrate. A strong inverse relationship was observed between density...
Abstract Pacific lamprey (Lampetra tridentata) in the Columbia River Basin have declined to a remnant of their pre-1940s populations and the status of the western brook lamprey (L. richardsoni) is unknown. Identifying the biological and ecological factors limiting lamprey populations is critical to their recovery, but little research has been conducted on these species within the Columbia River Basin. This ongoing, multi-year study examines lamprey populations in Cedar Creek, Washington, a third-order tributary to the Lewis River. This annual report describes the activities and results of the second year of this project. Adult (n = 24), metamorphosed (n = 247), transforming (n =4), and ammocoete (n = 387) stages...
Mitochondrial DNA variation among 1246 individuals of Pacific lamprey (Entosphenus tridentatus) from 81 populations spanning 2600 km from the Skeena River, British Columbia, to the Ventura River, California, was surveyed using five restriction enzymes. A total of 29 composite haplotypes was detected in two gene fragments (ND2 and ND5). The three most common haplotypes, occurring in 91% of all samples, were present at similar frequencies in all regions. Samples were divided into six biogeographic regions based on sample distribution and geographical landmarks to assess geographic genetic structure. Analysis of molecular variance indicated that 99% of the genetic variation was explained by variability within drainages....
Pacific Northwest National Laboratory (PNNL) initiated studies to evaluate the swimming performance and behavior of juvenile Pacific lamprey (Lampetra tridentata). Studies were conducted both in the laboratory under controlled conditions and in the field. This information was needed to provide for future guidelines regarding juvenile lamprey downstream passage survivorship at hydroelectric dams located within the Columbia River basin. Our initial objectives (initiated in 1999) involved conducing studies to determine impingement rates using 1/8-in. bar screens, swimming performance, and effects of shear forces on juvenile lamprey. In 2000, we expanded our evaluation to include impingement rates using different screen...
Pacific lamprey (Lampetra tridentata) is the largest and most abundant lamprey species in the Snake and Columbia River system. Because the Pacific Lamprey is a native anadromous species, the U.S. Army Corps of Engineers has an interest in facilitating its protection at federally operated hydroelectric projects. Pacific Northwest National Laboratory (PNNL) conducted a study in 2002 to ascertain the effects of the modified extended-length submerged bar screens (ESBS) on juvenile Pacific lamprey at John Day Dam. The project focused on three tasks. The first consisted of in situ video observations of lamprey encountering the modified ESBS within an operating turbine intake at John Day Dam. The second was to infer the...
This study describes phenetic characteristics and examines the life history of anadromous Arctic lamprey Lethenteron camtschaticum and freshwater-resident Alaskan brook lamprey Lethenteron alaskense in two tributaries of the middle Yukon River, Alaska. Larval lampreys could not be identified to species using pigmentation density patterns or trunk myomere counts, but adults could be identified to species based on colouration, body size and oral-disc dentition. Although larvae were patchily distributed in both rivers, there was a greater proportion of sample locations where Lethenteron spp. were absent in upper reaches than in middle and lower reaches. Relative abundance, density and median and maximum total length...
The objective of this project was to assess genetic population structure in Entosphenus tridentatus (Pacific lamprey) to evaluate whether this lamprey exhibits fidelity to natal streams or regions. I investigated genetic variability in 1246 individuals of E. tridentatus from 81 populations spanning 2600 km of the North American Pacific coast from the Skeena River, British Columbia to the Ventura River, California. Genetic variability was assessed in a 2690 base pair nucleotide sequence of mitochondrial DNA using five restriction enzymes. All unique restriction fragment patterns were sequenced, with the complete data matrix including nucleotide variation at 19 positions. The data matrix contained 29 haplotypes with...
This study is the first to document genetic differences among Pacific lampreys Lampetra tridentata across much of their range. We examined collections of migrating adult Pacific lampreys from the Naka River, Japan; Moose River, Alaska; and six Pacific Northwest locations (North Fork Toutle, Willamette, Deschutes, John Day, Rogue, and Klamath rivers) based on variation at 180 polymorphic loci among the 556 amplified fragment length polymorphism loci generated by seven primer combinations. Despite the large geographical distances separating the samples, the different collections were characterized by a high proportion of shared bands, which indicated significant levels of historical gene flow across the range of the...
Most species with lengthy migrations display some degree of natal homing; some (e.g. migratory birds and anadromous salmonids) show spectacular feats of homing. However, studies of the sea lamprey (Petromyzon marinus) indicate that this anadromous species locates spawning habitat based on pheromonal cues from larvae rather than through philopatry. Previous genetic studies in the anadromous Pacific lamprey (Entosphenus tridentatus) have both supported and rejected the hypothesis of natal homing. To resolve this, we used nine microsatellite loci to examine the population structure in 965 Pacific lamprey from 20 locations from central British Columbia to southern California and supplemented this analysis with mitochondrial...
Executive Summary • This project used nine newly-developed microsatellite markers to determine if there is broad-scale population structure in Pacific lamprey populations. • It expanded on a previous study which applied these markers to nine Pacific lamprey populations from British Columbia, Washington State, Oregon, and California. • The current project provided funding for five additional sites within California; seven additional sites in British Columbia, Washington State, Oregon, and California were included with funding from the Docker laboratory at the University of Manitoba. • A total of 965 Pacific lampreys were genotyped from these 21 sites. • A total of nine sites were included from California: the Trinity...
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