Ex. 281-US-414

A report on the preliminary studies of systematics and juvenile ecology of Upper Klamath Lake sucker

Size-structured spatial patterns as a measure of larval dispersal and emigration

Size-structured spatial patterns in larvae of 2 sucker and 3 minnow species are described from fixed-site sampling in Upper Klamath Lake, Oregon, and are used to demonstrate patterns of size-based losses downstream and retention in the lake. The smallest larvae of shortnose suckers (Chasmistes brevirostris), Lost River suckers (Deltistes luxatus), and tui chubs (Siphateles bicolor) were least likely to be found in Lake Ewauna, a downstream catchment; yet the proportion of larger larvae downstream was often substantial, 20%–40% of a size class. In contrast, the smallest larvae of blue chubs (Klamathella coerulea) and fathead minnows (Pimephales promelas) were least likely to be found in restoration marshes. For these 2 species, interannual differences in spatial size-structuring was variable, with larger size classes being found in high proportions in restoration marshes in some years but not in others. These patterns may be indicative of substantial emigration from Upper Klamath Lake, in the case of suckers and tui chubs, and of variable use of restoration marshes by larger blue chubs and fathead minnows. Although this and other approaches can provide insight into larval emigration and movement, spatially intensive sampling and knowledge of circulation patterns may allow for more rigorous estimates of larval movements.This is the publisher’s final pdf. The published article is copyrighted by Brigham Young University and can be found at: https://ojs.lib.byu.edu/ojs/index.php/wnan

The environment and biological community of the lower York River, Virginia : a literature review

Section 1: Physical and chemical parameters / R.A. Jordan Section 2: Phytoplankton and primary productivity / R.A. Jordan Section 3: Zooplankton and meroplankton / R.A. Jordan Section 4: Benthos and shellfish / M.E. Bender Section 5: Finfish / Douglas Markle

Introgressive Hybridization and the Evolution of Lake-Adapted Catostomid Fishes.

Hybridization has been identified as a significant factor in the evolution of plants as groups of interbreeding species retain their phenotypic integrity despite gene exchange among forms. Recent studies have identified similar interactions in animals; however, the role of hybridization in the evolution of animals has been contested. Here we examine patterns of gene flow among four species of catostomid fishes from the Klamath and Rogue rivers using molecular and morphological traits. Catostomus rimiculus from the Rogue and Klamath basins represent a monophyletic group for nuclear and morphological traits; however, the Klamath form shares mtDNA lineages with other Klamath Basin species (C. snyderi, Chasmistes brevirostris, Deltistes luxatus). Within other Klamath Basin taxa, D. luxatus was largely fixed for alternate nuclear alleles relative to C. rimiculus, while Ch. brevirostris and C. snyderi exhibited a mixture of these alleles. Deltistes luxatus was the only Klamath Basin species that exhibited consistent covariation of nuclear and mitochondrial traits and was the primary source of mismatched mtDNA in Ch. brevirostris and C. snyderi, suggesting asymmetrical introgression into the latter species. In Upper Klamath Lake, D. luxatus spawning was more likely to overlap spatially and temporally with C. snyderi and Ch. brevirostris than either of those two with each other. The latter two species could not be distinguished with any molecular markers but were morphologically diagnosable in Upper Klamath Lake, where they were largely spatially and temporally segregated during spawning. We examine parallel evolution and syngameon hypotheses and conclude that observed patterns are most easily explained by introgressive hybridization among Klamath Basin catostomids

Age, growth, and long-distance dispersal in the western North Atlantic of vexillifer larvae of the pearlfish, Echiodon dawsoni, with notes on Carapus bermudensis (Ophidiiformes: Carapidae)

We examined 120 vexillifer larvae of Echiodon dawsoni and 40 of Carapus bermudensis collected from the continental shelf and slope of the Gulf of Mexico and the western North Atlantic to Nova Scotia. Age was estimated for a subset of vexillifers, from which otoliths (sagittae) were excised and growth increments were recognizable, and a linear, estimated age at length relation was constructed. Spawning appeared to be year round for both species across their range. All estimated age classes of Ec. dawsoni were collected south of 35 °N, but north of 35 °N all vexillifers of Ec. dawsoni were older than 55 days. Only one C. bermudensis was collected north of 35 °N. The occurrence of vexillifers of Ec. dawsoni north of Cape Hatteras, North Carolina, USA, indicates long-distance dispersal to inhospitable habitats and might be related to their spawning farther offshore than C. bermudensis, in regions where their vexillifers are more likely to be entrained into the Gulf Stream and transported northeastward.Keywords: Carapus bermudensis, Echiodon dawsoni, Vexillifers, Growth, Dispersa

Timing of Population Fragmentation in a Vulnerable Minnow, the Umpqua Chub, and the Role of Nonnative Predators

We examined the distribution of Umpqua Chub Oregonichthys kalawatseti, an endemic, vulnerable minnow in western Oregon, and whether six ecological populations (based on distribution patterns) had sufficient genetic cohesion to be considered evolutionary populations. We also evaluated the influence of Holocene geological events and recent nonnative predator introductions on the timing of population formation or fragmentation. Based on data from 10 microsatellite loci, we found evidence for four evolutionary populations of Umpqua Chub. One population, in the Smith River, is isolated by the Umpqua estuary and is more than 100 river kilometers from the other three populations: Elk Creek, Calapooya CreekOlalla Creek, and Cow CreekSouth Umpqua River. Quantile regression was used to examine the timing of genetic divergence among evolutionary populations assuming a genetic isolation-by-distance model. The quantile regression suggested that the genetic differentiation index (F [subscript ST]) should change by at least 0.0002/km; most fragmentation was recent and with similar timing, but the Smith River isolation event may have been about 2-4times older. We could not distinguish whether the timing of the Smith River isolation corresponded to the last major tsunami event or the introduction of Striped Bass Morone saxatilis, a likely predator. All population fragmentation appears to be relatively recent, with the three upstream populations restricted to third- and fourth-order streams, most likely fragmented by either nonnative Smallmouth Bass Micropterus dolomieu, which now dominate sixth-order streams, or in the case of Elk Creek, a dam. The mid-drainage CalapooyaOlalla population was the most genetically diverse and appeared to be a mix of the other populations, which showed a significant isolation-by-distance relationship to this population. We hypothesize that Umpqua Chub populations have formed and fragmented by peripheral isolation from a larger population, the remnant of which is the mid-drainage CalapooyaOlalla population. Received April 20, 2012; accepted August 25, 2012Keywords: Conservation, Regression quantiles, River, Program, Oregon Chub, Genetic

Evolution of the Rhinichthys Osculus Complex (Teleostei: Cyprinidae) in Western North America.

We studied Rhinicthys osculus and its close relatives to discover evolutionary processes that operated to produce this widespread, polytypic fish group in an intermountain landscape of hundreds of small, isolated drainages. This group has attracted study because of its many ambiguously distinctive populations, in which homoplastic traits are shared across local geographic barriers. The observed morphological ambiguity is clarified by phylogenetic analyses of mtDNA data from 73 locations, which show deep divergences separating several dozen hypothetically monophyletic groups.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/136783/1/MP204 vol2.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/136783/2/Rhinichthys Appendix MP204 vol2.pdfDescription of MP204 vol2.pdf : Main ArticleDescription of Rhinichthys Appendix MP204 vol2.pdf : Datase