24 results on '"Paul, Andrew J."'
Search Results
2. Unveiling the recovery dynamics of walleye after the invisible collapse
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Cahill, Christopher L., Walters, Carl J., Paul, Andrew J., Sullivan, Michael G., and Post, John R.
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Walleye (Fish) -- Environmental aspects -- Distribution -- Forecasts and trends ,Market trend/market analysis ,Company distribution practices ,Earth sciences - Abstract
Walleye (Sander vitreus) populations in Alberta, Canada, collapsed by the mid-1990s and were a case study in the paper Canada's Recreational Fisheries: The Invisible Collapse? Here we fit age-structured population dynamics models to data from a landscapescale monitoring program to assess walleye population status and reconstruct recruitment dynamics following the invisible collapse. Assessments indicated that populations featured low [F.sub.msy] values of approximately 0.2-0.3 under conservative assumptions for the stock-recruitment relationship but that many populations were lightly exploited during 2000-2018. Recruitment reconstructions showed that recovery from collapse in 33/55 lakes was driven in part by large positive recruitment anomalies that occurred during 1998-2002. Additionally, 15/55 lakes demonstrated cyclic recruitment dynamics. The documented recruitment anomalies and cyclic fluctuations could be due to environmental effect(s) or cannibalism, and experimentation is likely necessary to resolve this uncertainty. These findings contribute new information on the recovery dynamics of walleye following the invisible collapse and demonstrate the effectiveness of coupling traditional fisheries science models with broad-scale monitoring data to improve understanding of population dynamics and sustainability across landscapes. Au milieu des annees 1990, les populations de dore jaune (Sander vitreus) en Alberta (Canada) s'etaient effondrees, constituant une etude de cas dans l'article intitule Canada's Recreational Fisheries: The Invisible Collapse? Nous calons des modeles de dynamique de la population structures par age sur des donnees issues d'un programme de surveillance a l'echelle du paysage dans le but d'evaluer l'etat des populations de dore jaune et de reconstituer la dynamique du recrutement dans la foulee de l'effondrement invisible. Des evaluations indiquent que les populations presentent de faibles valeurs de [F.sub.msy] d'environ 0,2-0,3 pour des hypotheses prudentes concernant la relation de recrutement au stock, mais que de nombreuses populations ont ete legerement exploitees durant la periode de 2000 a 2018. Les reconstitutions du recrutement montrent que le retablissement suivant l'effondrement dans 33 lacs sur 55 etait partiellement mu par d'importantes anomalies positives du recrutement qui se sont produites durant la periode de 1998 a 2002. En outre, 15 lacs sur 55 presentaient une dynamique de recrutement cyclique. Les anomalies de recrutement et les fluctuations cycliques documentees pourraient etre dues a un ou des effets environnementaux ou au cannibalisme, et des experiences sont probablement necessaires pour lever cette incertitude. Ces constatations fournissent de nouveaux renseignements sur la dynamique du retablissement du dore jaune dans la foulee de l'effondrement invisible et demontrent l'efficacite du jumelage de modeles traditionnels issus des sciences halieutiques a des donnees de surveillance a grande echelle pour ameliorer la comprehension de la dynamique et de la perennite des populations a l'echelle du paysage. [Traduit par la Redaction], Introduction The invisible collapse of inland recreational fisheries is among the most influential papers published in fisheries science (hereinafter 'invisible collapse'; Post et al. 2002 in Sass and Allen 2014). [...]
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- 2022
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3. Myxobolus cerebralis establishment and spread: a graphical synthesis
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Ramazi, Pouria, Fischer, Samuel M., Alexander, Julie, James, Clayton T., Paul, Andrew J., Greiner, Russell, and Lewis, Mark A.
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Myxozoans -- Identification and classification -- Distribution ,Graphic methods -- Usage ,Company distribution practices ,Earth sciences - Abstract
Myxobolus cerebralis is the parasite causing whirling disease, which has dramatic ecological impacts due to its potential to cause high mortality in salmonids. The large-scale efforts, necessary to underpin an effective surveillance program, have practical and economic constraints. There is, hence, a clear need for models that can predict the parasite spread. Model development, however, often heavily depends on knowing influential variables and governing mechanisms. We have developed a graphical model for the establishment and spread of M. cerebralis by synthesizing experts' opinion and empirical studies. First, we conducted a series of workshops with experts to identify variables believed to impact the establishment and spread of the parasite M. cerebralis and visualized their interactions via a directed acyclic graph. Then we refined the graph by incorporating empirical findings from the literature. The final graph's nodes correspond to variables whose considerable impact on M. cerebralis establishment and spread is either supported by empirical data or confirmed by experts, and the graph's directed edges represent direct causality or strong correlation. This graphical model facilitates communication and education of whirling disease and provides an empirically driven framework for constructing future models, especially Bayesian networks. Myxobolus cerebralis, le parasite a l'origine de la myxosomiose, a des impacts ecologiques importants en raison de la forte mortalite que cette maladie peut entrainer chez les salmonides. Les efforts a grande echelle necessaires a un programme de surveillance efficace sont limites par des facteurs tant pratiques qu'economiques, d'ou le besoin de modeles permettant de predire la propagation du parasite. Souvent, le developpement de modeles requiert une connaissance des variables importantes et des mecanismes en cause. Nous avons developpe un modele graphique de l'etablissement et de la propagation de M. cerebralis reposant sur la synthese d'opinions de specialistes et d'etudes empiriques. Nous avons d'abord mene une serie d'ateliers avec des specialistes dans le but de cerner les variables qui joueraient un role dans l'etablissement et la propagation de M. cerebralis et produit une visualisation de leurs interactions sur un graphe acyclique oriente. Nous avons ensuite raffine le graphe en y incorporant des constatations empiriques tirees de travaux publies. Les nreuds du graphe final correspondent aux variables dont l'impact considerable sur l'etablissement et la propagation de M. cerebralis est soit appuye par des donnees empiriques ou confirme par des specialistes, et les aretes orientees du graphe representent une causalite directe ou une forte correlation. Ce modele graphique facilite la communication et la sensibilisation relatives a la myxosomiose et fournit un cadre de nature empirique pour le developpement de modeles futurs, notamment des reseaux bayesiens. [Traduit par la Redaction], 1. Introduction Myxobolus cerebralis (Myxozoa, Bivalvulida: Myxobolidae) (Hofer 1903) is a parasite that infects salmonids, including trout and whitefish, resulting in whirling disease. The parasite invades the fish via the [...]
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- 2022
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4. Myxobolus cerebralisestablishment and spread: a graphical synthesis
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Ramazi, Pouria, primary, Fischer, Samuel M., additional, Alexander, Julie, additional, James, Clayton T., additional, Paul, Andrew J., additional, Greiner, Russell, additional, and Lewis, Mark A., additional
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- 2022
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5. Prioritizing bull trout recovery actions using a novel cumulative effects modelling framework.
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MacPherson, Laura M., Reilly, Jessica R., Neufeld, Kenton R., Sullivan, Michael G., Paul, Andrew J., and Johnston, Fiona D.
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TROUT ,BROOK trout ,CHAR fish ,SPECIES - Abstract
Complexity of addressing cumulative effects that vary in space and time, especially for species occupying large ranges, makes conservation and recovery of populations difficult. In Alberta, declines of all three native stream trout species led to them being listed as species at risk. We developed a novel, semi‐quantitative cumulative effects modelling process to quantify threats using stressor‐response curves with a single common response scale, wherein inputs were determined for each population, and outputs were used to create population‐specific recovery action hypotheses to inform management. Using a case study of bull trout recovery in Rocky Creek, Alberta, we tested these hypotheses using a before–after control‐impacted design. Recovery actions positively affected bull trout, and the modelling approach provided insight into threats (sedimentation and angling effort) that most likely limited the population. [ABSTRACT FROM AUTHOR]
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- 2024
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6. Are Alberta’s Northern Pike Populations at Risk from Walleye Recovery?
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Paul, Andrew J., primary, Cahill, Christopher L., additional, MacPherson, Laura, additional, Sullivan, Michael G., additional, and Brown, Myles R., additional
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- 2021
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7. A spatial-temporal approach to modeling somatic growth across inland recreational fisheries landscapes
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Cahill, Christopher L., Anderson, Sean C., Paul, Andrew J., MacPherson, Laura, Sullivan, Michael G., van Poorten, Brett, Walters, Carl J., and Post, John R.
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Walleye (Fish) -- Growth ,Fish populations -- Growth -- Management -- Environmental aspects ,Company growth ,Company business management ,Earth sciences - Abstract
We develop a mechanistically motivated von Bertalanffy growth model to estimate growth rate and its predictors from spatial-temporal data and compare this model's performance with a suite of commonly used mixed-effects growth models. We test these models with simulated data and then apply them to test whether concerns that high density is causing growth suppression of walleye (Sander vitreus) in Alberta, Canada, are supported using data collected during 2000-2017. Simulation experiments demonstrated that models that failed to account for complex dependency structures often resulted in growth rate estimates that were less accurate and biased low as judged by median absolute relative error and median relative error, respectively. The magnitude of this bias depended on the parameter values used for simulation. For the case study, a spatial-temporal model was more parsimonious and had higher predictive performance relative to simpler models and did not support the slow-growing walleye hypothesis in Alberta. These findings demonstrate the importance of considering spatial-temporal correlation in analyses that rely on surveillance-style monitoring datasets, particularly when examining relationships between life-history traits and environmental characteristics. Nous developpons un modele de croissance de von Bertalanffy a relations mecanistes pour estimer le taux de croissance et ses variables predictives a partir de donnees spatiotemporelles et comparons la performance de ce modele a une serie de modeles de croissance a effets mixtes couramment utilises. Nous mettons ces modeles a l'essai en utilisant des donnees simulees et les appliquons ensuite pour verifier si des donnees recueillies de 2000 a 2017 appuient l'interpretation proposee qu'une forte densite causerait une suppression de la croissance de dores jaunes (Sander vitreus) en Alberta (Canada). Des experiences de simulation demontrent que les modeles qui ne tiennent pas compte de structures de dependance complexes produisent souvent des estimations des taux de croissance moins exactes et biaisees vers le bas, comme indique par l'erreur relative mediane absolue et l'erreur relative mediane, respectivement. La magnitude de ce biais depend des valeurs des parametres utilisees pour la simulation. Pour l'etude de cas, un modele spatiotemporel s'avere plus parcimonieux et presente une meilleure performance predictive que les modeles plus simples et n'appuie pas l'hypothese des dores a croissance lente en Alberta. Ces resultats demontrent l'importance de tenir compte des correlations spatiotemporelles dans les analyses qui reposent sur des ensembles de donnees de type surveillance, en particulier pour l'examen des relations entre des caracteres du cycle biologique et des caracteristiques du milieu ambiant. [Traduit par la Redaction], Introduction Inland recreational fisheries are embedded in complex social-ecological systems (see Carruthers et al. 2019), generate ~US$51 billion * [year.sup.-1] in North America (Funge-Smith 2018), and support important ecosystem services [...]
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- 2020
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8. Dude, Where's my Transmitter? Probability of Radio Transmitter Detections and Locational Errors for Tracking River Fish
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Watkins, Owen B., primary, Paul, Andrew J., additional, Spencer, Stephen C., additional, Sullivan, Michael G., additional, and Foote, Lee, additional
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- 2019
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9. Seasonal timing of reproductive migrations in adfluvial bull trout: an assessment of sex, spawning experience, population density, and environmental factors
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Sinnatamby, R. Niloshini, Pinto, Madalena C., Johnston, Fiona D., Paul, Andrew J., Mushens, Craig J., Stelfox, Jim D., Ward, Hillary G.M., and Post, John R.
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Spawning -- Research ,Salvelinus -- Behavior ,Fishes -- Migration ,Fishes -- Research ,Earth sciences - Abstract
Using individual tags combined with a fish fence operated at the mouth of Smith-Dorrien Creek, the primary spawning habitat for Lower Kananaskis Lake bull trout (Salvelinus confluentus), we approximated a complete census of the spawning population from 1996 to 2000 to assess whether timing of upstream and downstream spawning migrations varied with extrinsic and intrinsic factors. The timing of both upstream and downstream migrations varied with sex, previous spawning experience, density, and temperature. Inferred spawning duration based on the predicted upstream and downstream migration dates indicated that experienced female spawners spent the least amount of time upstream and first-time spawners spent the most time upstream. No consistent differences in upstream migration timing were observed between non-repetitive and repetitive spawners. We suggest that variations in spawning migration timing observed in Lower Kananaskis Lake may be linked to environmental factors that influence upstream swimming ability and acquisition and expenditure of energy with respect to reproduction. En utilisant des etiquettes individuelles combinees a une cloture a poissons installee a l'embouchure du ruisseau Smith-Dorrien, le principal habitat de frai pour l'omble a tete plate (Salvelinus confluentus) du lac Kananaskis inferieur, nous avons obtenu un recensement complet approximatif de la population reproductrice de 1996 a 2000, afin d'evaluer si le moment des avalaisons et devalaisons de frai variait en fonction de facteurs extrinseques et intrinseques. Le moment des avalaisons et des devalaisons variait selon le sexe, l'experience de reproduction anterieure, la densite et la temperature. La duree inferee du frai etablie a la lumiere des dates predites d'avalaison et de devalaison indique que les femelles reproductrices experimentees passaient le moins de temps en amont et que les nouveaux geniteurs passaient le plus de temps en amont. Aucune difference coherente du moment de l'avalaison n'a ete observee entre les nouveaux geniteurs et les geniteurs experimentes. Nous proposons que les variations du moment des migrations de frai observees dans le lac Kananaskis inferieur pourraient etre reliees a des facteurs environnementaux qui influencent la capacite de nager vers l'amont et l'acquisition et les depenses d'energie associees a la reproduction. [Traduit par la Redaction], Introduction Bull trout (Salvelinus confluentus), a coldwater fish species native to western North America, was once widely distributed throughout mountain and foothill rivers and lakes. Over the past century, bull [...]
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- 2018
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10. Multiple challenges confront a high-effort inland recreational fishery in decline
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Cahill, Christopher L., Mogensen, Stephanie, Wilson, Kyle L., Cantin, Ariane, Sinnatamby, R. Nilo, Paul, Andrew J., Christensen, Paul, Reilly, Jessica R., Winkel, Linda, Farineau, Anne, and Post, John R.
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Fishing -- Forecasts and trends -- Environmental aspects -- Laws, regulations and rules ,Fishery policy -- Methods ,Government regulation ,Market trend/market analysis ,Earth sciences - Abstract
Catch-and-release regulations designed to protect fisheries may fail to halt population declines, particularly in situations where fishing effort is high and when multiple stressors threaten a population. We demonstrate this claim using Alberta's Bow River, which supports a high-effort rainbow trout (Oncorhynchus mykiss) fishery where anglers voluntarily release >99% of their catch. We examined the population trend of adult trout, which were tagged and recaptured using electrofishing surveys conducted intermittently during 2003-2013. We constructed Bayesian multisession capture-recapture models in Stan to obtain abundance estimates for trout and regressed trend during two periods to account for variation in sampling locations. General patterns from all models indicated the population declined throughout the study. Potential stressors to this system that may have contributed to the decline include whirling disease (Myxobolus cerebralis), which was detected for the first time in 2016, notable floods, and release mortality. Because disease and floods are largely uncontrollable from a management perspective, we suggest that stringent tactics such as angler effort restrictions may be necessary to maintain similar fisheries. La reglementation sur la peche avec remise a l'eau visant a proteger les ressources halieutiques peut ne pas prevenir le declin de populations, particulierement dans des situations ou l'effort de peche est grand et de multiples facteurs de stress menacent une population. Nous faisons la demonstration de ce postulat avec l'exemple de la riviere Bow, en Alberta, qui supporte une peche a la truite arc-en-ciel (Oncorhynchus mykiss) a effort eleve dans laquelle les pecheurs remettent volontairement a l'eau plus de 99% de leurs prises. Nous avons examine la tendance demographique de truites adultes qui ont ete etiquetees et recapturees dans le cadre de releves a la peche electrique menes de maniere intermittente de 2003 a 2013. Nous avons construit des modeles bayesiens de capture-recapture a sessions multiples dans le logiciel Stan pour obtenir des estimations de l'abondance pour les truites et obtenu une tendance par regression pour deux periodes pour tenir compte de la variation des lieux d'echantillonnage. Les motifs generaux obtenus de tous les modeles indiquent que la population a baisse tout au long de l'etude. Les facteurs de stress pour ce systeme qui pourraient avoir joue un role dans cette baisse comprennent le tournis des truites (infection a Myxobolus cerebralis), qui a ete detecte pour la premiere fois en 2016, des inondations notables et la mortalite apres remise a l'eau. Comme il est difficilement possible de controler, dans une perspective de gestion, les infections et les inondations, nous suggerons que des mesures draconiennes, comme des restrictions de l'effort des pecheurs a la ligne, pourraient etre necessaries pour assurer le maintien de ressources halieutiques semblables. [Traduit par la Redaction], Introduction Recreational fisheries can decline and collapse when exploitation rate is high relative to the productivity of the targeted population (Post et al. 2002; Sullivan 2003; Johnston et al. 2007), [...]
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- 2018
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11. Instream Flow Needs in Streams and Rivers: The Importance of Understanding Ecological Dynamics
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Anderson, Kurt E., Paul, Andrew J., McCauley, Edward, Jackson, Leland J., Post, John R., and Nisbet, Roger M.
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- 2006
12. Changes in migratory fish communities and their health, hydrology, and water chemistry in rivers of the Athabasca oil sands region: a review of historical and current data
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Schwalb, Astrid N., Alexander, Alexa C., Paul, Andrew J., Cottenie, Karl, and Rasmussen, Joseph B.
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Fish populations -- Environmental aspects -- Health aspects ,Animal migration -- Environmental aspects -- Health aspects ,Rivers -- Environmental aspects -- Health aspects ,Environmental issues - Abstract
The long-lived migratory fish in the lower Athabasca region (including the Athabasca oil sands region) are valued ecosystem components and good bio-indicators of changes in habitat condition, water quality and quantity over the entire stream network. Changes in this region may have been caused by a variety of human activities including oil sands development, forestry, urban development, and recreational activities. We reviewed existing data to examine whether community composition and health of migratory fish (such as northern pike, walleye, and suckers) in the lower Athabasca region have changed over the past 40 years and whether these could be explained by changes in hydrology or water chemistry. Declines of 53%-100% in the abundance of three migratory fish species were detected in the Muskeg watershed (15% land change). Significant changes in fish health were detected. The largest decreases in body condition of fish in the region occurred in the late 1990s and coincided with elevated levels of fin erosion, the most frequently occurring external abnormality, and with extreme discharge conditions. Fish habitat can be affected by both increases and decreases in discharge, and the most pronounced changes were increases in some watersheds of up to 20% of average discharge post-development. In contrast, decreases in discharge post-development in the Muskeg and Steepbank rivers correlated with a decrease in precipitation. Our results show that climatic events and landscape features such as wetlands are important for understanding changes in the system. Further research is needed to examine potential ecological consequences of the observed changes in hydrology for fish and to explore what caused the changes in migratory fish communities and fish health. This will require a better understanding of the trophic structure of the system and a better monitoring program for migratory fish. Key words: biodiversity decline, land use changes, cumulative effects, long-term monitoring protocol, climate change, network scale, Alberta, Athabasca River. Les poissons migrateurs a longue duree de vie dans la region inferieure de l'Athabasca (incluant la region des sables bitumineux de l'Athabasca) constituent des ecosystemes de valeur et de bons bio-indicateurs des changements des conditions d'habitat, soit la qualite et la quantite de l'eau sur l'ensemble du reseau de rivieres. Les changements survenus dans cette region ont pu etre causes par une variete d'activites humaines incluant le developpement des sables bitumineux, la foresterie, le developpement urbain et les activites de recreation. Les auteurs ont passe en revue les donnees existantes pour examiner si la composition de la communaute et la sante des poissons migrateurs (p. ex. brochet du nord, dore, meunier) dans la region inferieure de l'Athabasca ont change au cours des 40 dernieres annees et si elles peuvent s'expliquer par des changements de l'hydrologie et de la chimie de l'eau. On a observe des declins de 53 a 100% dans l'abondance de ces trois especes de poissons migrateurs dans le bassin du Muskeg (15% de changement du territoire). On a egalement detecte des changements significatifs dans la sante des poissons. Les plus importantes deteriorations des conditions corporelles des poissons de la region sont survenues a la fin des annees 90 et coincident avec des degres eleves d'erosion des nageoires, l'anormalite externe survenant le plus frequemment, ainsi qu'avec des conditions extremes de decharge. L'habitat des poissons peut etre affecte aussi bien par des augmentations que des diminutions de decharge et les changements les plus marques augmentent dans certains bassins avec des decharges moyennes apres developpement de 20%. A l'oppose, les diminutions des decharges apres developpement dans le Muskeg et les rivieres encavees montrent une correlation avec une diminution des precipitations. Les resultats obtenus par les auteurs montrent que les evenements climatiques et les caracteristiques du paysage, comme les terres humides, sont d'importance pour comprendre les changements dans le systeme. Il faut plus de recherche pour examiner les consequences ecologiques potentielles des changements observes dans l'hydrologie sur les poissons et pour explorer ce qui a cause les changements dans les communautes des poissons migrateurs ainsi que leur mortalite. Ceci necessitera une meilleure comprehension de la structure trophique du systeme et un meilleur programme de suivi pour les poissons migrateurs. [Traduit par la Redaction] Mots-cles : declin de la biodiversite, changement d'utilisation des terres, protocole de suivi a long terme, changement climatique, echelle du reseau, Alberta, Riviere Athabasca., Introduction The lower Athabasca River region in northern Alberta is the focus of oil sands development (Fig. 1). This river and its associated tributaries and delta support a rich assemblage [...]
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- 2015
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13. Lateral and Longitudinal Displacement of Stream-Rearing Juvenile Bull Trout in Response to Upstream Migration of Spawning Adults
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Pinto, Madalena C., primary, Post, John R., additional, Paul, Andrew J., additional, Johnston, Fiona D., additional, Mushens, Craig J., additional, and Stelfox, Jim D., additional
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- 2013
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14. Environmental flows and recruitment of walleye (Sander vitreus) in the Peace-Athabasca Delta
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Paul, Andrew J.
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Walleye (Fish) -- Research ,Streamflow -- Research ,Earth sciences - Abstract
Age composition data from a commercial walleye (Sander vitreus) fishery in the Peace-Athabasca Delta were used to test the hypotheses that recruitment varied interannually and that recruitment was related to local hydrological conditions. Variable interannual recruitment was strongly supported over a null model of constant annual recruitment. Assuming recruitment strength was established in a walleye's first year of life, several a priori hypotheses relating recruitment to river discharge or lake levels were tested using an information-theoretic approach. The data best supported the hypothesis of a positive relationship between walleye recruitment and mean discharge in the Athabasca River during the fry rearing period (weeks 18-43). Approximately 25% of observed variability in annual recruitment could be explained by mean discharge during the fry period. However, the data could not fully rule out the alternate hypotheses that recruitment was related to mean discharge in the Athabasca River over the entire year or during winter. Several mechanisms are hypothesized to explain the positive relationship, including increased space in preferred open-water habitat or greater food production from nutrient inputs or wetted area. The observed correlation between river discharge and walleye recruitment can be used to help us understand water management planning on the Athabasca River. Des donnees sur la composition selon l'age issues d'une peche commerciale au dore jaune (Sander vitreus) dans le delta des rivieres de la Paix et Athabasca ont ete utilisees pour verifier des hypotheses selon lesquelles le recrutement varie d'une annee a l'autre et qu'il est relie aux conditions hydrologiques locales. Les donnees appuyaient fortement l'existence d'une variabilite interannuelle du recrutement comparativement a l'hypothese nulle d'un recrutement annuel constant. En partant du principe que la force du recrutement est etablie durant la premiere annee de vie du dore jaune, plusieurs hypotheses a priori associant le recrutement au debit des rivieres ou au niveau des lacs ont ete verifiees en empruntant une approche basee sur la theorie de l'information. L'hypothese qu'appuyaient le plus fortement les donnees etait celle d'une relation positive entre le recrutement de dores et le debit moyen de la riviere Athabasca durant la periode d'alevinage (semaines 18 a 43). Environ 25 % de la variabilite observee du recrutement annuel pouvait etre expliquee par le debit moyen durant la periode d'alevinage. Les donnees ne pouvaient toutefois exclure completement les autres hypotheses d'un recrutement relie au debit moyen annuel ou hivernal de la riviere Athabasca. Plusieurs mecanismes sont proposes pour expliquer la relation positive observee, dont l'espace accru dans les habitats d'eau libre privilegies par le dore ou une production de nourriture accrue associee aux apports de nutriment ou aux zones mouillees. La correlation observee entre le debit des rivieres et le recrutement de dores jaunes peut servir a une meilleure comprehension de la planification de la gestion de l'eau de la riviere Athabasca. [Traduit par la Redaction], Introduction Understanding the relationship between river discharge (i.e., flow) and ecological processes is fundamental to making informed water management decisions (Anderson et al. 2006). However, developing flow-ecology relationships is difficult, [...]
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- 2013
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15. The demography of recovery of an overexploited bull trout, Salvelinus confluentus, population
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Johnston, Fiona D., Post, John R., Mushens, Craig J., Stelfox, Jim D., Paul, Andrew J., and Lajeunesse, Brian
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Fish populations -- Evaluation ,Trout -- Environmental aspects ,Human beings -- Influence on nature ,Human beings -- Evaluation ,Earth sciences - Abstract
Abstract: An exploited bull trout, Salvelinus confluentus, population experienced a 28-fold increase in adult density during a 10-year period from a minimum of 60 individuals. This demonstrates the extent to [...]
- Published
- 2007
16. Estimation of gillnet efficiency and selectivity across multiple sampling units: A hierarchical Bayesian analysis using mark-recapture data
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Askey, Paul J., primary, Post, John R., additional, Parkinson, Eric A., additional, Rivot, Etienne, additional, Paul, Andrew J., additional, and Biro, Peter A., additional
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- 2007
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17. Can Anglers Influence the Abundance of Native and Nonnative Salmonids in a Stream from the Canadian Rocky Mountains?
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Paul, Andrew J., primary, Post, John R., additional, and Stelfox, Jim D., additional
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- 2003
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18. Canada's Recreational Fisheries: The Invisible Collapse?
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Post, John R., primary, Sullivan, Michael, additional, Cox, Sean, additional, Lester, Nigel P., additional, Walters, Carl J., additional, Parkinson, Eric A., additional, Paul, Andrew J., additional, Jackson, Leyland, additional, and Shuter, Brian J., additional
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- 2002
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19. Spatial Distribution of Native and Nonnative Salmonids in Streams of the Eastern Slopes of the Canadian Rocky Mountains
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Paul, Andrew J., primary and Post, John R., additional
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- 2001
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20. Density-dependent intercohort interactions and recruitment dynamics: models and a bull trout (Salvelinus confluentus) time series
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Paul, Andrew J, primary, Post, John R, additional, Sterling, George L, additional, and Hunt, Carl, additional
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- 2000
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21. Effects of Pulsed and Continuous DC Electrofishing on Juvenile Rainbow Trout
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Ainslie, Barbara J., primary, Post, John R., additional, and Paul, Andrew J., additional
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- 1998
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22. Regulation of Rotifers by Predatory Calanoid Copepods (Subgenus Hesperodiaptomus) in Lakes of the Canadian Rocky Mountains
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Paul, Andrew J., primary and Schindler, David W., additional
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- 1994
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23. Density-dependent intercohort interactions and recruitment dynamics: models and a bull trout (Salvelinus confluentus) time series
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Post, John R, Paul, Andrew J, Sterling, George L, and Hunt, Carl
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- 2000
24. Trophic interactions in fishless alpine lakes of the Canadian Rocky Mountains
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Paul, Andrew J.
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- 1994
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