Consequences of Hatch Phenology on Stages of Fish Recruitment

Little is known about how hatch phenology (e.g., the start, peak, and duration of hatching) could influence subsequent recruitment of freshwater fishes into a population. We used two commonly sympatric fish species that exhibit different hatching phenologies to examine recruitment across multiple life stages. Nine yellow perch (Perca flavescens) and bluegill (Lepomis macrochirus) annual cohorts were sampled from 2004 through 2013 across larval, age-0, age-1, and age-2 life stages in a Nebraska (U.S.A.) Sandhill lake. Yellow perch hatched earlier in the season and displayed a more truncated hatch duration compared to bluegill. The timing of hatch influenced recruitment dynamics for both species but important hatching metrics were not similar between species across life stages. A longer hatch duration resulted in greater larval yellow perch abundance but greater age-1 bluegill abundance. In contrast, bluegill larval and age-0 abundances were greater during years when hatching duration was shorter and commenced earlier, whereas age-0 yellow perch abundance was greater when hatching occurred earlier. As a result of hatch phenology, yellow perch recruitment variability was minimized sooner (age-0 life stage) than bluegill (age-1 life stage). Collectively, hatch phenology influenced recruitment dynamics across multiple life stages but was unique for each species. Understanding the complexities of when progeny enter an environment and how this influences eventual recruitment into a population will be critical in the face of ongoing climate change

Examining the Relevancy and Utility of the American Fisheries Society Certification Program to Prepare Future Fisheries Professionals

Fisheries science is a diverse field that requires individuals to be knowledgeable in many disciplines in addition to fisheries (e.g., economics, sociology, political science, chemistry; Kelso and Murphy 1988). This challenges students attempting to enter a career in fisheries, as well as academic institutions and eventual employers, to develop both depth and breadth of knowledge needed to succeed in the profession (Oglesby and Krueger 1989). The preparedness and competency of young professionals entering the workforce has long been a problem (Stauffer and McMullin 2009). Several constraints and ongoing challenges facing the profession have continued to magnify these issues over time (McMullin et al., this issue). These issues stem from the diversity of skills required or expected across employer groups (e.g., government agencies, private sectors, nongovernment organizations) and degree levels sought (B.Sc., M.Sc., Ph.D.), complexity of fisheries-related problems, and balancing a broad academic focus with specific training. Additionally, employers perceive that students lack welldeveloped critical thinking, communication, and statistical skills that are highly desired in any area of fisheries. The American Fisheries Society’s (AFS) mission of preparing and promoting the development of fisheries professionals has been addressed in many ways, including development of the AFS Professional Certification Program in 1963. This program provides minimum standards for which fisheries professionals are recognized across government, academic, and nongovernment entities. The certification program fosters greater recognition that fisheries professionals are well equipped and prepared to act on the public’s behalf concerning fisheries-related issues. Two tiers of certification exist, with first-tier certification (Associate Fisheries Professional) contingent upon the completion of higher education courses in six broad subject areas. In this article, we focus on the first tier of certification, the basic education determined by AFS to be critical in preparing young professionals for a career in fisheries

Are We Preparing the Next Generation of Fisheries Professionals to Succeed in their Careers?: A Survey of AFS Members

Natural resource professionals have frequently criticized universities for poorly preparing graduates to succeed in their jobs. We surveyed members of the American Fisheries Society to determine which job skills and knowledge of academic topics employers, students, and university faculty members deemed most important to early-career success of fisheries professionals. Respondents also rated proficiency of recently hired, entry-level professionals (employers) on how well their programs prepared them for career success (students and faculty) in those same job skills and academic topics. Critical thinking and written and oral communication skills topped the list of important skills and academic topics. Employers perceived recent entry-level hires to be less well-prepared to succeed in their careers than either university faculty or students. Entry-level hires with post-graduate degrees rated higher in proficiency for highly important skills and knowledge than those with bachelor’s degrees. We conclude that although universities have the primary responsibility for developing critical thinking and basic communication skills of students, employers have equal or greater responsibility for enhancing skills of employees in teamwork, field techniques, and communicating with stakeholders. The American Fisheries Society can significantly contribute to the preparation of young fisheries professionals by providing opportunities for continuing education and networking with peers at professional conferences. ¿Estamos preparando a la siguiente generación de profesionales en pesquerías para que tengan éxito en sus carreras?: una encuesta a miembros de la AFS Los profesionales de los recursos naturales, con frecuencia, han criticado a las universidades por la preparación deficiente de los graduados para tener éxito en sus trabajos. En este trabajo se encuestaron a miembros de la Sociedad Americana de Pesquerías para determinar qué conocimiento de tópicos académicos y habilidades laborales consideran los empleados, estudiantes y miembros de facultades universitarias como las más importantes en los profesionales de las pesquerías para tener éxito al inicio de sus carreras. Los encuestados también reconocieron las habilidades de los profesionistas regresados y contratados (empleados) o qué tan bien sus programas académicos los preparaban para tener éxito en sus carreras (estudiantes y facultad) en las mismas habilidades laborales y tópicos académicos. El pensamiento crítico y las habilidades de comunicación oral y escrita encabezaron la lista de habilidades y tópicos académicos importantes. Los empleadores percibieron a las contrataciones recientes como menos preparadas para tener éxito en sus carreras que los miembros de la facultad o los propios estudiantes. Los individuos recién contratados con posgrado fueron mejor calificados en cuanto a poseer el conocimiento y las habilidades más importantes que los titulados de licenciatura. Concluimos que si bien las universidades tienen la responsabilidad primordial de desarrollar el pensamiento crítico y las habilidades de comunicación en los estudiantes, los empleadores tienen la misma o mayor responsabilidad para fomentar las habilidades de sus trabajadores en lo referente a trabajo en equipo, técnicas de trabajo en campo, y comunicación con los involucrados en las pesquerías. La Sociedad Americana de Pesquerías puede contribuir significativamente a preparar a los jóvenes profesionistas de las pesquerías mediante el otorgamiento de oportunidades para continuar con su educación y el establecimiento de redes de contactos, durante conferencias, con pares y profesionales. Préparons-nous la prochaine génération de professionnels de la pêche à réussir leur carrière?: Un sondage auprès des membres AFS Les professionnels des ressources naturelles ont fréquemment critiqué les universités, car elles préparent mal les diplômés à réussir leur carrière. Nous avons interrogé les membres de l’American Fisheries Society pour déterminer quelles compétences professionnelles et quelles connaissances académiques les employeurs, étudiants et membres du corps professoral des universités jugent les plus importantes pour le succès des professionnels de la pêche au début de leur carrière. Les répondants ont également évalué l’aptitude des professionnels récemment entrés sur le marché du travail (employeurs) ou dans quelle mesure les programmes les ont préparés à réussir leur carrière (étudiants et professeurs) dans ces mêmes compétences professionnelles et sujets académiques. La pensée critique, les compétences en communication écrite et orale étaient en tête de la liste des compétences et des sujets académiques importants. Les employeurs ont perçu les professionnels récemment entrés sur le marché du travail moins bien préparés pour réussir dans leur carrière que les professeurs d’université ou les étudiants. Les employés au niveau d’entrée possédant des diplômes postuniversitaires étaient mieux notés dans la maîtrise des compétences et des connaissances très importantes que ceux ne possédant que des diplômes de baccalauréat. Nous concluons que, bien que les universités aient la responsabilité principale de développer la pensée critique et les compétences en communication de base des étudiants, les employeurs ont la responsabilité égale ou supérieure d’améliorer ces compétences dans le travail d’équipe, les techniques de terrain et la communication avec les parties prenantes. L’American Fisheries Society peut contribuer de manière significative à la préparation des jeunes professionnels de la pêche en offrant des possibilités de formation continue et de réseautage avec des pairs lors de conférences professionnelles

Potential Direct and Indirect Effects of Climate Change on a Shallow Natural Lake Fish Assemblage

Much uncertainty exists around how fish communities in shallow lakes will respond to climate change. In this study, we modelled the effects of increased water temperatures on consumption and growth rates of two piscivores (northern pike [Esox lucius] and largemouth bass [Micropterus salmoides]) and examined relative effects of consumption by these predators on two prey species (bluegill [Lepomis macrochirus] and yellow perch [Perca flavescens]). Bioenergetics models were used to simulate the effects of climate change on growth and food consumption using predicted 2040 and 2060 temperatures in a shallow Nebraska Sandhill lake, USA. The patterns and magnitude of daily and cumulative consumption during the growing season (April–October) were generally similar between the two predators. However, growth of northern pike was always reduced (–3 to –45% change) compared to largemouth bass that experienced subtle changes (4 to –6% change) in weight by the end of the growing season. Assuming similar population size structure and numbers of predators in 2040–2060, future consumption of bluegill and yellow perch by northern pike and largemouth bass will likely increase (range: 3–24%), necessitating greater prey biomass to meet future energy demands. The timing of increased predator consumption will likely shift towards spring and fall (compared to summer), when prey species may not be available in the quantities required. Our findings suggest that increased water temperatures may affect species at the edge of their native range (i.e. northern pike) and a potential mismatch between predator and prey could exist

First Measurement of Coherent Elastic Neutrino-Nucleus Scattering on Argon

We report the first measurement of coherent elastic neutrino-nucleus scattering (\cevns) on argon using a liquid argon detector at the Oak Ridge National Laboratory Spallation Neutron Source. Two independent analyses prefer \cevns over the background-only null hypothesis with greater than $3\sigma$ significance. The measured cross section, averaged over the incident neutrino flux, is (2.2 $\pm$ 0.7) $\times$10$^{-39}$ cm$^2$ -- consistent with the standard model prediction. The neutron-number dependence of this result, together with that from our previous measurement on CsI, confirms the existence of the \cevns process and provides improved constraints on non-standard neutrino interactions.Comment: 8 pages, 5 figures with 2 pages, 6 figures supplementary material V3: fixes to figs 3,4 V4: fix typo in table 1, V5: replaced missing appendix, V6: fix Eq 1, new fig 3, V7 final version, updated with final revision

Ventilatory drive and the apnea-hypopnea index in six-to-twelve year old children

BACKGROUND: We tested the hypothesis that ventilatory drive in hypoxia and hypercapnia is inversely correlated with the number of hypopneas and obstructive apneas per hour of sleep (obstructive apnea hypopnea index, OAHI) in children. METHODS: Fifty children, 6 to 12 years of age were studied. Participants had an in-home unattended polysomnogram to compute the OAHI. We subsequently estimated ventilatory drive in normoxia, at two levels of isocapnic hypoxia, and at three levels of hyperoxic hypercapnia in each subject. Experiments were done during wakefulness, and the mouth occlusion pressure measured 0.1 seconds after inspiratory onset (P(0.1)) was measured in all conditions. The slope of the relation between P(0.1 )and the partial pressure of end-tidal O(2 )or CO(2 )(P(ET)O(2 )and P(ET)CO(2)) served as the index of hypoxic or hypercapnic ventilatory drive. RESULTS: Hypoxic ventilatory drive correlated inversely with OAHI (r = -0.31, P = 0.041), but the hypercapnic ventilatory drive did not (r = -0.19, P = 0.27). We also found that the resting P(ET)CO(2 )was significantly and positively correlated with the OAHI, suggesting that high OAHI values were associated with resting CO(2 )retention. CONCLUSIONS: In awake children the OAHI correlates inversely with the hypoxic ventilatory drive and positively with the resting P(ET)CO(2). Whether or not diminished hypoxic drive or resting CO(2 )retention while awake can explain the severity of sleep-disordered breathing in this population is uncertain, but a reduced hypoxic ventilatory drive and resting CO(2 )retention are associated with sleep-disordered breathing in 6–12 year old children