bluuebunny/crossref_metadata_2025 huggingface dataset:
The Late Paleozoic fold-thrust structure of the Tunka bald mountains, East Sayan (southern framing of the Siberian Platform)
Authors: Ryabinin A.B. , Buslov M.M. , Zhimulev F.I. , Travin A.V.
Published: December 2011

According to the new geological, geochronological, and structural data, the Tunka bald mountains (East Sayan) have a nappe structure, which formed in the Late Carboniferous–Early Permian. The deformations have been dated by the 40Ar–39Ar method on the basis of syntectonic micas and amphiboles, whose structural and spatial positions have been determined in oriented thin sections. The geometrical analysis of macro- and microstructures has revealed three development stages of the structures, which followed one another in progressive deformation. The first (thrust-fault) stage (316–310 Ma) comprised a group of N-verging thrust sheets. In the second (fold deformation) stage (305–303 Ma), they were folded. The third (strike-slip fault) stage (286 Ma) comprised high-angle shears, along which V-shaped blocks were squeezed westward from the most compressed areas. All the structures developed under near-N–S-trending compression. The thrusting in the Tunka bald mountains was coeval with the major shear structures in the eastern Central Asian Fold Belt (Main Sayan Fault, Kurai, Northeastern, and Irtysh crumpled zones, etc.). Also, it was simultaneous with the formation of continental-margin calc-alkalic and shoshonite series (305–278 Ma) as well as that of the alkali and alkali-feldspar syenites and granites (281–278 Ma) of the Tarim mantle plume in the Angara–Vitim pluton, located near and east of the studied region. Thus, the simultaneous development of the Late Paleozoic structures, active-margin structures, and plume magmatism in southern Siberia might have resulted from the global geodynamic events caused by the interaction between the tectonic plates which formed the Central Asian Fold Belt.
Marine radiocarbon reservoir corrections (ΔR) for Chesapeake Bay and the Middle Atlantic Coast of North America
Authors: Rick Torben C. , Henkes Gregory A. , Lowery Darrin L. , Colman Steven M. , Culleton Brendan J.
Published: December 2011

Radiocarbon dates from known age, pre-bomb eastern oyster (Crassostrea virginica) shells provide local marine reservoir corrections (ΔR) for Chesapeake Bay and the Middle Atlantic coastal area of eastern North America. These data suggest subregional variability in ΔR, ranging from 148±46 14C yr on the Potomac River to −109±38 14C yr at Swan Point, Maryland. The ΔR weighted mean for the Chesapeake's Western Shore (129±22 14C yr) is substantially higher than the Eastern Shore (−88±23 14C yr), with outer Atlantic Coast samples falling between these values (106±46 and 2±46 14C yr). These differences may result from a combination of factors, including 14C-depleted freshwater that enters the bay from some if its drainages, 14C-depleted seawater that enters the bay at its mouth, and/or biological carbon recycling. We advocate using different subregional ΔR corrections when calibrating 14C dates on aquatic specimens from the Chesapeake Bay and coastal Middle Atlantic region of North America.
A new triad resonance between co-propagating surface and interfacial waves
Authors: Alam Mohammad-Reza
Published: December 2011

In a two-layer density-stratified fluid it is known, due to Ball (J. Fluid Mech., vol. 19, 1964, p. 465), that two oppositely travelling surface waves may form a triad resonance with an interfacial wave. Ball claims ‘there are no other interactions’ between two surface waves and one interfacial wave. Contrary to this, here we present a new class of triad resonance that occurs between two co-propagating surface waves and one interfacial wave. While in Ball’s resonance the interfacial wave has a wavelength of about half of two surface waves, in the new resonance presented here the interfacial wave has a much higher wavelength compared to those of surface waves. This, together with the unidirectionality of the participant triplet, makes the realization of the new resonance more likely in real ocean scenarios. We further show, via theoretical analysis and direct simulation, that, unique to this new class of resonance, the triad inevitably undergoes a cascade of (near-) resonance interaction that spreads the energy of initial waves to a number of lower and higher harmonics. The significance of the resonance studied here is, particularly, more emphasized in the littoral zones, where the spectrum refracts toward a unidirectional wave train.
A UNIQUENESS RESULT FOR THE FOURIER TRANSFORM OF MEASURES ON THE SPHERE
Authors: GONZÁLEZ VIELI FRANCISCO JAVIER
Published: December 2011

A finite measure supported by the unit sphere 𝕊n−1 in ℝn and absolutely continuous with respect to the natural measure on 𝕊n−1 is entirely determined by the restriction of its Fourier transform to a sphere of radius r if and only 2πr is not a zero of any Bessel function Jd+(n−2)/2 with d a nonnegative integer.
13.—Sea-floor Sediment Mapping by Sonar Methods
Authors: Chesterman W. Deryck
Published: December 2011

Synopsis

A system is described which produces true-to-scale sonar maps of the sediment patterns on the seabed of the Continental Shelf waters. Correction is made for the speed of the ship over ground, and the 'drift angle' of the sonar beam during passage from one station to another. Work at sea has been extended to water depths of 250 metres, and the technique has been widely used for cable route surveys.
On signs of Fourier coefficients of cusp forms
Authors: MATOMÄKI KAISA
Published: December 2011

We consider two problems concerning signs of Fourier coefficients of classical modular forms, or equivalently Hecke eigenvalues: first, we give an upper bound for the size of the first sign-change of Hecke eigenvalues in terms of conductor and weight; second, we investigate to what extent the signs of Fourier coefficients determine an unique modular form. In both cases we improve recent results of Kowalski, Lau, Soundararajan and Wu. A part of the paper is also devoted to generalized rearrangement inequalities which are utilized in an alternative treatment of the second question.
Historical Explanation in ‘The Critique of Dialectical Reason’
Authors: Warnock Mary
Published: December 2011

The Critique of Dialectical Reason was first
published in France twenty years ago, in 1960. The book, we know from Simone
de Beauvoir, was flung together in a hurry, written virtually without
correction during the height of the Algerian war, a period, for Sartre, of
stress and anxious stock-taking of his position as a Marxist and a long-term
non-joiner of the Communist Party. The whole sense in which, in 1960, Sartre
was a Marxist, the question of precisely how eccentric his kind of Marxism
was, is centred on his theory of historical explanation. I do not propose to
raise many detailed questions about the relation of Sartre's views on
history to those of Marx himself, still less to those of other Marxists.
Ignorance alone would rule out such a course. I would like if I can,
however, to consider Sartre's own view of historical explanation as it
appears in the Critique, and leave it to others
if they wish to fit it into the Marxist tradition, or exclude it. In order
to perform this relatively modest expository task, it will be necessary for
me to refer, from time to time, to Sartre's earlier philosophical views. But
this will come in incidentally
The Seasons and Transhumance in the Safaitic Inscriptions
Authors: Macdonald M. C. A.
Published: December 2011

According to Musil, the bedouin of North Arabia know five seasons, distinguished by different types of rain or its absence. The rains within each season are also thought to be governed by particular stars. The following table sets out these five seasons with the associated rains and stars.
DO OIL SHOCKS DRIVE BUSINESS CYCLES? SOME U.S. AND INTERNATIONAL EVIDENCE
Authors: Engemann Kristie M. , Kliesen Kevin L. , Owyang Michael T.
Published: December 2011

Oil prices rose sharply prior to the onset of the 2007–2009 recession. Hamilton [in thePalgrave Dictionary of Macroeconomics(2008)] noted that nine of the last ten recessions in the United States were preceded by a substantial increases in the price of oil. In this paper, we consider whether oil price shocks significantly increase the probability of recessions in a number of countries. Because business cycle turning points generally are not available for other countries, we estimate the turning points together with oil's effect in a Markov-switching model with time-varying transition probabilities. We find that, for most countries, oil shocks do affect the likelihood of entering a recession. In particular, for a constant, zero-term spread, an average-sized shock to WTI oil prices increases the probability of recession in the United States by nearly 50 percentage points after one year and nearly 90 percentage points after two years.
Decoupling electrocaloric effect from Joule heating in a solid state cooling device
Authors: Quintero M. , Ghivelder L. , Gomez-Marlasca F. , Parisi F.
Published: December 2011

We report a heat dynamics analysis of the electrocaloric effect (ECE) in commercial multilayer capacitors based on BaTiO3 dielectric, a promising candidate for applications as a solid state cooling device. Direct measurements of the time evolution of the sample’s temperature changes under different applied voltages allow us to decouple the contributions from Joule heating and from the ECE. Heat balance equations were used to model the thermal coupling between different parts of the system. Fingerprints of Joule heating and the ECE could be resolved at different time scales. We argue that Joule heating and the thermal coupling of the device to the environment must be carefully taken in to account in future developments of refrigeration technologies employing the ECE.
Atomistic pseudopotential theory of optical properties of exciton complexes in InAs/InP quantum dots
Authors: Gong Ming , Zhang Weiwei , Can Guo Guang , He Lixin
Published: December 2011

The photoluminescence (PL) spectra of exciton complexes in quantum dots (QDs) are of primary importance to understand their optical properties, which are well understood in InAs/GaAs QDs both theoretically and experimentally. However the knowledge can not be directly applied to InAs/InP QDs. In this work, we investigate the differences of the PL spectra of the two dots using an empirical pseudopotential method. The alignment of exciton complex transition lines of the two QDs are very different and the reasons are explained. We show that the “hidden” correlation energies in InAs/InP QDs are smaller than those in InAs/GaAs QDs and the lifetime of exciton complexes in InAs/InP QDs are about twice longer than those in InAs/GaAs QDs.
Evidence of Metapopulation Dynamics in Shortnose Sturgeon in the Southern Part of Their Range
Authors: Peterson Douglas L. , Farrae Daniel J.
Published: December 2011

The shortnose sturgeon Acipenser brevirostrum is one of the most endangered members of the sturgeon family because of overexploitation, depressed population levels, and a shrinking range. The lack of historical data on shortnose sturgeon populations has led to an increase in sturgeon research over the last three decades; however, most recent studies have not focused on southern populations. The objective of this study was to estimate the abundance, annual survival, and temporary emigration rates of shortnose sturgeon in the Ogeechee River, Georgia. Shortnose sturgeon were captured with gill and trammel nets for a mark–recapture analysis from 1 June to 31 August in each of the 3 years from 2007 to 2009. Over the three summers of sampling, we conducted a total of 864 net sets and captured 168 individual shortnose sturgeon with an additional 51 recaptures. Our analysis revealed that the best‐fitting robust design population models incorporated interactions among water temperature, dissolved oxygen, and total effort in which capture and recapture probabilities were set equal and temporary emigration parameters were set to zero or held constant. Abundance estimates (95% confidence interval [CI]) were 404 (175–633), 264 (126–402), and 203 (32–446) individual sturgeon for 2007, 2008, and 2009, respectively. Population parameter estimates of annual survival and temporary emigration, combined with documented emigration and immigration of tagged individuals to and from the adjacent Altamaha River, provided evidence that the Ogeechee River stock is not discrete but possibly a metapopulation with the Altamaha River.
Estimating Genetic Composition in Introgressed Largemouth Bass Populations: Does Age Matter?
Authors: Dumont Spencer C. , Lutz-Carrillo Dijar J.
Published: December 2011

In estimating population-level introgression for largemouth bass Micropterus salmoides populations, it is unclear which age-class, if any, is most appropriate to sample and what biases may be introduced by the sampling of specific age-classes. Estimates of introgression between Florida largemouth bass M. salmoides floridanus and northern largemouth bass M. salmoides salmoides in six populations were made based on seven microsatellite loci from different age-classes and combinations of age-classes. Levels of introgression were not significantly different for 40 of 42 pairwise age-class comparisons within reservoirs or for five of six comparisons between age-0 fish and adults. In addition, measures of precision based on each estimate were similar within reservoirs. These results suggest that age-0 largemouth bass samples can be used to make accurate and precise estimates of introgression at the population level. However, these results also suggest that alternate year-classes or combinations of year-classes with or without the inclusion of age-0 samples are equally suitable for estimating introgression at the population level. Thus, the selection of specific age-classes to be sampled for estimating introgression in largemouth bass populations should be based on the efficiency with which the age-classes can be collected.

Received February 15, 2010; accepted November 17, 2010
An Application of Behavioral Modeling to Characterize Urban Angling Decisions and Values
Authors: Bingham Matthew F. , Li Zhimin , Mathews Kristy E. , Spagnardi Colleen M. , Whaley Jennifer S. , Veale Sara G. , Kinnell Jason C.
Published: December 2011

Although many recreational anglers reside in urban areas, important policy questions, such as how to optimally improve urban shorelines and increase urban angler participation rates, are unresolved. This article presents an econometric model that quantifies the relationships between site quality, angler characteristics, and urban angling behavior in five northeastern New Jersey counties. The model employed (repeated nested logit) is prominent in the environmental economics literature but has not to our knowledge been applied to urban fishery management. The results indicate that the repeated nested logit can effectively characterize urban anglers’ site choices, participation rates, and resource values. The article presents two models whose differences highlight considerations in modeling urban angling behavior. The first includes variables typically found in recreational-fishing, site-choice models. The second (and preferred) model includes variables that more appropriately characterize urban angling. This model predicts approximately 2,341,000 total annual trips. Adding a fishing site in a centrally located but industrial area (Newark) generates direct economic benefits to recreational anglers that are estimated at US$101,179 per year. The new site is expected to draw 1,571 trips annually. Of these trips, 154 are new and 1,417 are diverted from other sites. Adding a new site with similar characteristics on the same water body in a less industrial area (Garfield) generates estimated direct benefits of $312,419 per year. This new site draws an expected 14,814 trips annually. Of these trips, 247 arise from increased angling rates and 14,567 are diverted from other sites. These results illustrate the usefulness of this modeling approach for assessing management objectives. For example, a manager hoping to increase angling participation might prefer the Newark project if it could be completed at half the price; a manager intending to maximize social benefits or reduce pressure at other sites would pay a substantial premium for the Garfield project.

Received November 3, 2009; accepted December 30, 2010
Resolving Some of the Complexity of a Mixed-Origin Walleye Population in the East Basin of Lake Erie Using a Mark–Recapture Study
Authors: Zhao Yingming , Einhouse Donald W. , MacDougall Thomas M.
Published: December 2011

At least two genetically distinct populations of walleye Sander vitreus reproduce in Lake Erie: one west-basin-origin population and one east-basin-origin population. Each year, some west-basin-origin walleyes migrate to the east basin and create a mixed-origin walleye population. Uncertainties associated with this migratory behavior make it difficult to describe the dynamics of the east-basin-origin population. We used mark–recapture analysis to estimate the dynamics of the east-basin-origin walleye population and to measure the contribution of west-basin-origin walleyes to the total walleye harvest in the east basin. Compared with the west-basin-origin walleyes, the east-basin-origin walleyes experienced lower fishing pressure, lower natural mortality, and a higher survival rate. On average, the west-basin-origin walleye migrants comprised about 90% of the annual harvest in the east basin. The number of the west-basin-origin walleyes migrating to the east basin was linearly related to their abundance. Walleyes showed a strong fidelity to their spawning sites. This study provided an approach to the assessment of population dynamics and the management of walleye fisheries in the east basin of Lake Erie.

Received June 7, 2010; accepted December 30, 2010
Physiological Effects of Potassium Chloride, Formalin, and Handling Stress on Bonytail
Authors: Sykes Catherine L. , Caldwell Colleen A. , Gould William R.
Published: December 2011

We characterized the sublethal physiological changes in bonytail Gila elegans subjected to consecutive 750-mg/L potassium chloride (KCl) and 25-mg/L formalin treatments for the removal of zebra mussel Dreissena polymorpha and quagga mussel D. bugensis veligers. Plasma cortisol, glucose, and osmolality were measured over 24 h and at 14 d posthandling after exposing bonytail to KCl and one net stressor (capture with a net), KCl plus formalin and two net stressors, and one or two net stressors without chemicals. Elevated plasma cortisol (322–440 ng/mL) and glucose (254–399 mg/dL) concentrations were observed in all treatments compared with the concentrations in control fish (plasma cortisol, 56 ng/mL; glucose, 43 mg/dL). While there were no detectable differences in plasma osmolality among the treatment and control fish, a difference was observed between fish that were handled once versus twice. Chemical effects of stress were not observed in any of the physiological responses when the KCl treatment was compared with the one-net stressor treatment or when the KCl plus formalin treatment was compared with the two-net stressor treatment. Cumulative responses, however, were observed between one net stressor and two net stressors for plasma glucose and osmolality but not for plasma cortisol. Plasma cortisol and glucose levels remained elevated at 24 h posthandling, indicating that bonytail had not completely recovered from the handling stressors and would benefit from a recovery period in protected refugia before being released.

Received August 23, 2010; accepted January 20, 2011
Evaluating Benchmarks of Population Status for Pacific Salmon
Authors: Holt Carrie A. , Bradford Michael J.
Published: December 2011

Canada is developing an indicator approach for assessing the biological status of conservation units of Pacific salmon Oncorhynchus spp. under its Wild Salmon Policy that is based, in part, on the abundance of adult fish. Two benchmarks will be used to place populations in one of three abundance categories. The lower benchmark is proposed to be at a level that allows for a substantial buffer between it and the abundance that would result in a population's being assessed as at risk of extirpation based on quantitative criteria used by the Committee on the Status of Endangered Wildlife in Canada. Using Monte Carlo simulation, we evaluated eight candidate lower benchmarks calculated from parameters of the stock–recruit relationship against two criteria, the probability of extirpation over 100 years and the probability of recovery to spawner abundances that result in the maximum sustainable yield in one or three generations. For modeled populations of moderate size (unfished equilibrium abundances >25,000) and moderate productivity (∼four adult recruits produced per spawner at low spawner abundances), all benchmarks protected populations from extirpation when harvest restrictions were imposed at the lower benchmark. For small or unproductive populations, none of the benchmarks was adequate to prevent populations from being at risk of extirpation. However, those benchmarks that covaried with the productivity parameter of the stock–recruitment relationship performed better and are preferred to those that were derived mainly from estimates of habitat capacity.

Received May 31, 2010; accepted February 4, 2011
Balancing Biological Sustainability with the Economic Needs of Alaska's Sockeye Salmon Fisheries
Authors: Steiner Erin M. , Criddle Keith R. , Adkison Milo D.
Published: December 2011

Total revenue in the Bristol Bay, Alaska, fishery for sockeye salmon Oncorhynchus nerka has declined by 80% over the past two decades. In contrast to other fisheries where declining revenues are a consequence of declining catches, Bristol Bay sockeye salmon landings have remained high and the revenue decline is a result of falling prices, which in turn are a consequence of competition from increased production of rainbow trout/steelhead O. mykiss (hereafter, rainbow trout) and coho salmon O. kisutch farmed in Chile. This paper explores possible changes to current management strategies that would continue to ensure biological sustainability while enhancing economic returns. We simulate three management strategies for Bristol Bay sockeye salmon: fixed escapement range, conditional fixed harvest, and conditional fixed harvest rate. Yields from these simulations are combined with a forecast of Chilean rainbow trout and coho salmon production and a model of international trade flows for Alaskan sockeye salmon and Chilean coho salmon and rainbow trout to generate forecasts of exvessel price and total revenue for 2010 under each management strategy. The simulations suggest that a change from the current fixed escapement range management strategy could improve the economic health of the fishery without compromising biological sustainability.

Received March 2, 2010; accepted February 10, 2011
Dungeness Crab Mortality Due to Lost Traps and a Cost–Benefit Analysis of Trap Removal in Washington State Waters of the Salish Sea
Authors: Antonelis Kyle , Huppert Daniel , Velasquez Don , June Jeffrey
Published: December 2011

Loss of Dungeness crabs Cancer magister in derelict crab traps was estimated from catches and mortality in 24 simulated lost traps at two locations in Washington State. Equal numbers of recreational and commercial crab traps were initially baited and monitored weekly by divers until the bait was consumed and were monitored biweekly thereafter for 1 year. Dungeness crabs caught in the traps were individually tagged. Catch, escapement, retained catch, and mortality rates were estimated. The traps caught 1,077 Dungeness crabs, of which 500 (46%) died and 421 (39%) escaped. Mortality of sublegal males and females was expressed in legal male equivalents. The overall retained catch of Dungeness crabs (caught minus escaped) was 0.082 crabs·trap−1·d−1. After an initial lag, the cumulative daily mortality rate of Dungeness crabs rose steadily to 0.058 crabs·trap−1·d−1. An estimated 12,193 traps are lost annually in Washington waters of the Salish Sea, and the estimated trap fishing duration was 126 d for traps with escape cord (i.e., reflecting decomposition of the cord) and 2.2 years for traps without escape cord. Annual Dungeness crab loss was estimated at 178,874 legal male equivalents, translating to an exvessel value of US$744,296, or 4.5% of the value of recent harvests. Average annual net value to fishers from the saved Dungeness crabs (i.e., crabs available for harvest if lost traps had been removed) was estimated at $450,657–744,296 depending upon variable costs to harvest all of the saved crabs. Estimated net exvessel value of saved crabs ranged from $36.96 to $61.04 per removed trap compared with removal costs of $92.66–193.00 per trap. Removal of lost traps may be warranted in high-density fishing areas and for ecological reasons. Reducing the diameter of the escape cord and modifying the trap design could significantly reduce Dungeness crab mortality due to lost traps.

Received May 14, 2010; accepted February 10, 2011
Spawning Habitat Selection of Hickory Shad
Authors: Harris Julianne E. , Hightower Joseph E.
Published: December 2011

We examined the spawning habitat selectivity of hickory shad Alosa mediocris, an anadromous species on the Atlantic coast of North America. Using plankton tows and artificial substrates (spawning pads), we collected hickory shad eggs in the Roanoke River, North Carolina, to identify spawning timing, temperature, and microhabitat use. Hickory shad eggs were collected by both sampling gears in March and April. The results from this and three other studies in North Carolina indicate that spawning peaks at water temperatures between 12.0°C and 14.9°C and that approximately 90% occurs between 11.0°C and 18.9°C. Hickory shad eggs were collected in run and riffle habitats. Water velocity and substrate were significantly different at spawning pads with eggs than at those without eggs, suggesting that these are important microhabitat factors for spawning. Hickory shad eggs were usually collected in velocities of at least 0.1 m/s and on all substrates except those dominated by silt. Eggs were most abundant on gravel, cobble, and boulder substrates. Hickory shad spawned further upstream in years when water discharge rates at Roanoke Rapids were approximately average during March and April (2005 and 2007), as compared with a severe drought year (2006), suggesting that water flows may affect not only spawning site selection but also the quantity and quality of spawning habitat available at a macrohabitat scale. Using our field data and a Bayesian approach to resource selection analysis, we developed a preliminary habitat suitability model for hickory shad. This Bayesian approach provides an objective framework for updating the model as future studies of hickory shad spawning habitat are conducted.

Received July 16, 2010; accepted February 21, 2011
An Approach to Defining Stock Complexes for U.S. West Coast Groundfishes Using Vulnerabilities and Ecological Distributions
Authors: Cope Jason M. , DeVore John , Dick E. J. , Ames Kelly , Budrick John , Erickson Daniel L. , Grebel Joanna , Hanshew Gretchen , Jones Robert , Mattes Lynn , Niles Corey , Williams Sarah
Published: December 2011

The Magnuson–Stevens Fishery Conservation and Management Act (MSA) requires active management of all stocks at risk of overfishing or otherwise in need of conservation and management. In the Pacific Fishery Management Council groundfish fishery management plan, about two-thirds of the more than 90 managed stocks are currently without traditional assessments to help define stock status in relation to management targets. Stock complexes are often employed for management purposes in such situations. The guidelines issued in response to the 2006 MSA amendments defined a complex as a group of stocks with similar geographic distributions, life histories, and vulnerabilities to fisheries. This work uses productivity–susceptibility analysis (PSA) to measure the vulnerabilities of 90 managed groundfish stocks, 64 of which are currently managed within stock complexes. These stock complexes are reevaluated by first using a partitioning cluster analysis to group the stocks by depth and latitude. Vulnerability reference points are then established based on the PSA results to determine vulnerability groups of low, medium, high, and major concern within each ecological group. This method is a simple and flexible approach to incorporating vulnerability measures into stock complex designations while providing information with which to prioritize stock- and complex-specific management.

Received September 28, 2010; accepted February 23, 2011
Gender- and Year-Specific Mortality of Yellow Perch with Evidence of Compensatory Mortality
Authors: Schoenebeck Casey W. , Brown Michael L.
Published: December 2011

Gender- and year-specific survival (S) of yellow perch Perca flavescens, the tag recovery rate (f, i.e., the joint probability of a fish being harvested, the tag being recognized, and the tag being reported, corrected for tag loss and tagging mortality), and natural mortality (v) were estimated using Brownie tag recovery models. These models were constructed from 4 years of tagging and angler tag recovery data to determine whether mortality is additive or compensatory for the high- and low-quality yellow perch fishery types commonly found in eastern South Dakota glacial lakes. Natural mortality comprised the majority of total annual mortality, S was constant among years, and f was female-biased for both study populations. Survival and f did not vary among years for the low-quality population, providing inconclusive evidence of mortality function. However, a constant S coupled with annual changes in f and v (i.e., when harvest mortality increased, natural mortality decreased) suggests that mortality was compensatory for the high-quality population.

Received October 13, 2010; accepted March 3, 2011
Success or Failure? Do Indicator Selection and Reference Setting Influence River Rehabilitation Outcome?
Authors: Weber Christine , Peter Armin
Published: December 2011

Recovery indicators play a crucial role in the evaluation of river rehabilitation projects. Various types of biological indicators are used to address different ecosystem attributes (structure, composition, and function) at different levels of the biological hierarchy (population, guild, and community). Indicator values are evaluated against reference information from various sources, representing the conditions to be achieved (near-natural references) or to avoid (degraded references). We studied the extent to which investigators’ conclusions on project outcome were influenced by the indicator and reference types used. We analyzed 40 selected studies dealing with the recovery of riverine fish assemblages after active rehabilitation of physical habitat and lateral connectivity. In 32 (80%) of the 40 studies, fish response was measured at the population level. Structural and compositional indicators dominated (31 and 24 studies, respectively), while functional indicators were underrepresented (5 studies). Eighteen studies used multiple indicator types for a given ecosystem attribute, a given hierarchical level, or both. Among these studies, we found only very limited evidence that project outcome differed among different indicator types (1 study). In contrast, highly heterogeneous results were found within the different indicator types at the level of the individual study (i.e., indicators addressing the same hierarchical level and ecosystem attribute resulted in different evaluations of project outcome). Such heterogeneity was related to the spatiotemporal variability of the results and species-specific responses to physical habitat rehabilitation. Most studies (73%; 29 studies) used a single type of reference, and the majority focused on degraded conditions. Among the 10 studies that applied multiple reference types, one-third (3 studies) showed inconsistent results (i.e., one reference comparison produced a positive assessment for a given indicator, whereas the second comparison indicated that the endpoint was not achieved). We discuss the implications of inconsistent project outcomes for future monitoring activities.

Received July 6, 2010; accepted March 7, 2011
Freshwater Survival of Stranded Steelhead Kelts in Coastal Central California Streams
Authors: Barnett Lewis A. K. , Spence Brian C.
Published: December 2011

During 2008, spring drought conditions in the Santa Cruz Mountains of California resulted in hundreds of postspawn adult steelhead Oncorhynchus mykiss becoming stranded in streams and unable to return to sea. These individuals had no other option than to spend the entire summer and fall in freshwater habitats. As the fate of stranded kelts is poorly documented, we attempted to estimate the oversummer survival of steelhead kelts and to assess whether local habitat characteristics influenced survival rates. We found that nearly 40% of kelts observed during summer surveys were still alive in late October, just before the first significant rains of the season, and most individuals were observed to be in fair condition. Survival was higher for fish that resided in pools with substantial cover than for fish that occupied pools with only partial or no concealment. Overall, the unexpectedly high survival rates of stranded kelts suggest that the rescue and relocation of stranded steelhead to other habitats or to hatcheries may only be warranted when there are clear imminent threats to survival. Managers should consider the effects of strandings on population viability given that climate change may increase the frequency of strandings and decrease the survival of stranded individuals.

Received September 28, 2010; accepted April 28, 2011
Comparison of Retention Success for Multiple Tag Types in Common Snook
Authors: Boucek Ross E. , Adams Aaron J.
Published: December 2011

Tags are commonly used to uniquely identify fish in order to estimate population size, harvest rates, and fish behavior. However, some tags have the propensity to be shed (lost), which can bias results. To examine the shedding rates of external tags and the potential bias this introduces for common snook Centropomus undecimalis we marked adult snook with an internal 23-mm half duplex passive integrated transponder (PIT) tag (as a permanent mark) and one of two external tags: a T-bar anchor tag (44 mm; Floy, FD-68B) or a dart tag (89 mm × 2 mm; Floy, FT-1-94). Fish were tagged along sandy beaches of the Gulf of Mexico in southwestern Florida during the spawning season in 2007–2009. Short-term (37-d) external tag retention success was 100% for both tags. However, long-term (391-d) retention success was low for external tags (T-bar = 76%; dart = 38%). Given the limitations of and trade-offs among tag types, choosing the most appropriate tag will continue to challenge researchers. Until more universal tags are developed, researchers must carefully consider the advantages and disadvantages of each tag type with respect to different project objectives.

Received October 17, 2010; accepted May 19, 2011
Genetic Variation of Gray Triggerfish in U.S. Waters of the Gulf of Mexico and Western Atlantic Ocean as Inferred from Mitochondrial DNA Sequences
Authors: Antoni Luca , Emerick Nicholas , Saillant Eric
Published: December 2011

Gray triggerfish Balistes capriscus is a reef fish exploited by recreational and commercial fisheries in the southeastern United States. Recent stock assessments indicated that the species is overfished, and a rebuilding plan is in progress. The U.S. fishery is currently managed as a single stock owing to the absence of reliable information on stock structure. We sequenced a 617-base-pair fragment of the ND4 mitochondrial gene in a total of 150 specimens from five localities (South Texas, Louisiana, West Florida, southeastern Florida, and South Carolina) encompassing the exploited range of the species in the USA. Analysis of molecular variance, spatial analysis of molecular variance, and spatial autocorrelation analysis did not reveal significant spatial heterogeneity in haplotype distributions within the studied range. Significant departure from neutrality was inferred from neutrality tests and may reflect the signature of a rapid population expansion following the recent glacial epochs, an inference that was supported by the results of Bayesian coalescent analysis. While the present results are consistent with management of the species as a single stock, development of additional genetic markers is needed to increase the resolution in genetic analyses and evaluate fine-scale genetic stock structure in the region.

Received January 10, 2011; accepted May 5, 2011
Effect of Passive Integrated Transponder Tag Implantation Site on Tag Retention, Growth, and Survival of Two Sizes of Juvenile Bluegills and Yellow Perch
Authors: Kaemingk Mark A. , Weber Michael J. , McKenna Paul R. , Brown Michael L.
Published: December 2011

Passive integrated transponder (PIT) tags are commonly used to monitor growth, habitat use, activity rates, and survival of individual fish. However, for successful completion of research objectives, the tags must be retained and must not affect fish growth or survival. We compared the effects of PIT tagging location on tag retention, growth, and survival of juvenile bluegills Lepomis macrochirus and yellow perch Perca flavescens. In total, 80 bluegills and 80 yellow perch from two size-classes (75–101 and 128–162 mm total length) were randomly assigned to a control or to one of three tagging location treatments: isthmus, body cavity, or dorsal musculature. Fish received daily ad libitum rations and were monitored for survival. On days 14, 28, and 42, the fish were measured, weighed, and checked for tag retention. Use of the isthmus as a tagging location resulted in lower tag retention for both species and both size-classes relative to the body cavity and dorsal musculature locations. Tagging location had no detectable effect on growth or survival responses for either species or either size-class. Thus, PIT tags that are implanted in the dorsal musculature of large juvenile bluegills and yellow perch and in the body cavity of small juvenile bluegills and yellow perch can have high retention with minimal adverse effects.

Received May 4, 2011; accepted June 2, 2011
Mortality of Walleyes Angled from the Deep Waters of Rainy Lake, Minnesota
Authors: Talmage Philip J. , Staples David F.
Published: December 2011

Existing models of hooking mortality for walleyes Sander vitreus in large polymictic lakes are inadequate for estimating the number of catch-and-release mortalities in deeper, stratified lakes where fish are predominantly caught from depths greater than 10 m. To improve the understanding of how water depth affects catch-and-release mortality, logistic regression was used to investigate how depth of capture, fish length, and epilimnetic water temperature affect hooking mortality rates. In 2006 and 2007, 319 walleyes were caught by anglers at 5.8–17.1-m depths during a total of 10 angling events (July–September) on Rainy Lake, Minnesota. Fish were released into holding cages that allowed them the opportunity to reestablish themselves at their depths of capture; survival was recorded after 5 d (2 d for one cage). After accounting for the effects of experimental handling time (i.e., the time between hook removal and fish placement in the holding cage), capture depth had the largest effect on mortality; increases in either factor were associated with higher mortality rates. A mixed-effects model showed that pseudoreplication (i.e., correlations in survival rates among fish held in the same cage) did not detrimentally affect model parameter estimates or significance tests. In contrast to previous studies of hooking mortality in Minnesota, neither water temperature nor fish length best explained the mortality rates. By providing improvements over previous models, the logistic hooking mortality model developed in this study will allow managers to more effectively estimate hooking mortality rates in Rainy Lake and other deep lakes.

Received February 11, 2011; accepted May 13, 2011
Evaluation of Two Forms of Electroanesthesia and Carbon Dioxide for Short-Term Anesthesia in Walleye
Authors: Vandergoot Christopher S. , Murchie Karen J. , Cooke Steven J. , Dettmers John M. , Bergstedt Roger A. , Fielder David G.
Published: December 2011

Anesthetics immobilize fish, reducing physical damage and stress during aquaculture practices, stock assessment, and experimental procedures. Currently, only tricaine methanesulfonate (MS-222) is approved for use as an anesthetic for food fish in Canada and the United States; however, MS-222 can only be used with certain fish species, and treated fish must be held for a specified period of time before release into the wild. Two forms of electroanesthesia and carbon dioxide (CO2) were evaluated as anesthetics for adult walleye Sander vitreus to determine their suitability for use before intracoelomic implantation of telemetry transmitters. Walleyes were subjected to one of three treatment groups: constant direct current (CDC), pulsed direct current (PDC), and CO2. Fish subjected to these treatments were monitored for induction (where appropriate) and recovery time and whether these forms of anesthesia were conducive to implanting telemetry transmitters, that is, whether they fit a surgery threshold range of 250–350 s. Additionally, all fish were monitored for posttrial survival, and radiographs were taken to determine whether any vertebral damage was associated with the electroanesthesia treatments. Although all anesthetic treatments successfully immobilized fish for enough time to implant a transmitter, PDC electroanesthesia is recommended because of its immediate induction time, quick recovery, high immediate and short-term survival, and lack of evidence of vertebral abnormalities.

Received January 11, 2011; accepted May 24, 2011
The Effectiveness of Deepwater Release at Improving the Survival of Discarded Yelloweye Rockfish
Authors: Hochhalter Samuel J. , Reed Daniel J.
Published: December 2011

The effectiveness of deepwater release at improving the 17-d survival of discarded yelloweye rockfish Sebastes ruberrimus was determined by comparing an estimate of survival for individuals released at depth with an estimate of submergence probability for individuals released at the water's surface. A mark–recapture study was used to generate a maximum likelihood estimate of the 17-d survival probability of yelloweye rockfish (n = 182) caught by hook and line (depth = 18–72 m) and subsequently released at depth. The average Cormack–Jolly–Seber survival probability for yelloweye rockfish released at depth was remarkably high (0.988; 95% confidence interval = 0.478–0.999) and positively correlated with individual total length. Survival probability was not significantly influenced by the range of capture depths explored in this study or by exposure to barotrauma and other capture stressors. The submergence success of yelloweye rockfish released at the water's surface was 0.221 (95% confidence interval = 0.149–0.315), suggesting that the maximum survival potential of individuals released at the surface is low. The results of this study indicate that the average survival of discarded yelloweye rockfish can be substantially improved by deepwater release.

Received March 25, 2011; accepted June 22, 2011
The Importance of Trip Context for Determining Primary Angler Motivations: Are More Specialized Anglers More Catch-Oriented than Previously Believed?
Authors: Beardmore Ben , Haider Wolfgang , Hunt Len M. , Arlinghaus Robert
Published: December 2011

Most conclusions from general assessments of angler motivations indicate that noncatch motives are more important to anglers than catch motives. Such research usually assesses the general motivation structure by anglers. To assess both general and more context-specific angler motivations, we surveyed the same anglers from northeastern Germany using two phases of a complementary survey design. First, a 1-year diary was used to collect trip-specific information; second, a personalized mail survey was used to elicit context-specific motivation information. Anglers selected their most important motives for their most frequent trip–target species combination (i.e., context) from a list of 10 salient fishing motives. Anglers frequently cited catch motives as the most important across a range of target species, large-bodied species such as northern pike Esox lucius being primarily associated with trophy fishing. Some species (such as small-bodied cyprinids) were targeted for noncatch reasons, while others (such as European perch [also known as Eurasian perch] Perca fluviatilis) attracted anglers seeking a multitude of psychological outcomes. Five distinct angler types were identified based on similarity of prime fishing motivation, namely, trophy-seeking anglers; nontrophy, challenge-seeking anglers; nature-oriented anglers; meal-sharing anglers; and social anglers. Members of these angler groups were similar in demographics and general angling behaviors but differed with respect to several indicators of angler specialization, indicating that committed anglers are more catch-oriented than previously assumed.

Received November 12, 2010; accepted May 26, 2011
Spawning Habitat Unsuitability: An Impediment to Cisco Rehabilitation in Lake Michigan?
Authors: Madenjian Charles P. , Rutherford Edward S. , Blouin Marc A. , Sederberg Bryan J. , Elliott Jeff R.
Published: December 2011

The cisco Coregonus artedi was one of the most important native prey fishes in Lake Michigan and in the other four Laurentian Great Lakes. Most of the cisco spawning in Lake Michigan was believed to have occurred in Green Bay. The cisco population in Lake Michigan collapsed during the 1950s, and the collapse was attributed in part to habitat degradation within Green Bay. Winter water quality surveys of lower Green Bay during the 1950s and 1960s indicated that the bottom dissolved oxygen (DO) concentration was less than 2 mg/L throughout much of the lower bay, and most cisco eggs would not successfully hatch at such low DO concentrations. To determine present-day spawning habitat suitability in lower Green Bay, we compared cisco egg survival in lower Green Bay with survival at a reference site (St. Marys River, Michigan–Ontario) during 2009. We also conducted winter water quality surveys in lower Green Bay and the St. Marys River during 2009 and 2010. Cisco egg survival in lower Green Bay averaged 65.3%, which was remarkably similar to and not significantly different from the mean at the St. Marys River site (64.0%). Moreover, the lowest bottom DO concentrations recorded during the winter surveys were 11.2 mg/L in lower Green Bay and 12.7 mg/L in the St. Marys River. These relatively high DO concentrations would not be expected to have any negative effect on cisco egg survival. We conclude that winter water quality conditions in lower Green Bay were suitable for successful hatching of cisco eggs and that water quality during the egg incubation period did not represent an impediment to cisco rehabilitation in Lake Michigan. Our approach to determining spawning habitat suitability for coregonids would be applicable to other aquatic systems.

Received May 14, 2011; accepted July 6, 2011