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Paul J. B. Hart

Bio: Paul J. B. Hart is an academic researcher from University of Leicester. The author has contributed to research in topics: Foraging & Fisheries management. The author has an hindex of 42, co-authored 117 publications receiving 5657 citations. Previous affiliations of Paul J. B. Hart include University of Liverpool & University of Bergen.


Papers
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Journal ArticleDOI
TL;DR: It is shown that effective and accurate information transfer in groups may be gained only through nonlinear responses of group members to each other, thus highlighting the importance of quorum decision-making.
Abstract: Despite the growing interest in collective phenomena such as "swarm intelligence" and "wisdom of the crowds," little is known about the mechanisms underlying decision-making in vertebrate animal groups. How do animals use the behavior of others to make more accurate decisions, especially when it is not possible to identify which individuals possess pertinent information? One plausible answer is that individuals respond only when they see a threshold number of individuals perform a particular behavior. Here, we investigate the role of such "quorum responses" in the movement decisions of fish (three-spine stickleback, Gasterosteus aculeatus). We show that a quorum response to conspecifics can explain how sticklebacks make collective movement decisions, both in the absence and presence of a potential predation risk. Importantly our experimental work shows that a quorum response can reduce the likelihood of amplification of nonadaptive following behavior. Whereas the traveling direction of solitary fish was strongly influenced by a single replica conspecific, the replica was largely ignored by larger groups of four or eight sticklebacks under risk, and the addition of a second replica was required to exert influence on the movement decisions of such groups. Model simulations further predict that quorum responses by fish improve the accuracy and speed of their decision-making over that of independent decision-makers or those using a weak linear response. This study shows that effective and accurate information transfer in groups may be gained only through nonlinear responses of group members to each other, thus highlighting the importance of quorum decision-making.

454 citations

Journal ArticleDOI
TL;DR: The results suggest that, contrary to some previous studies on other animals, bold or shy behaviour in sticklebacks is consistent between contexts.
Abstract: Behavioural variation is known to occur between individuals of the same population competing for resources. Individuals also vary with respect to their boldness or shyness. An individual’s position along the shy-bold axis may be defined as the extent to which it is willing to trade off potentially increased predation risks for possible gains in resources. Similarly, group living may be interpreted as a trade-off between anti-predatory tactics and foraging efficiency. The responses of three-spined sticklebacks (Gasterosteus aculeatus) were tested across four social contexts to assess relative boldness or shyness and to further examine whether their behaviour would be consistent within and between contexts. Individuals displayed consistent responses within and between the first two contexts: those individuals which resumed foraging rapidly after a simulated aerial predator attack also displayed low shoaling tendencies. Such fish were deemed to be bold, whilst those which displayed the converse behaviour, slow resumption of foraging and a high shoaling tendency, were deemed to be shy. In a third context, bold individuals out-competed shy conspecifics for food. Boldness was also positively correlated with growth over a 6-week period. The position adopted by an individual within a group is usually interpreted as a trade-off between predation risk and foraging efficiency—both are greater at the front of a mobile group. Bold individuals showed significantly stronger tendencies towards front positions than shy conspecifics. The results suggest that, contrary to some previous studies on other animals, bold or shy behaviour in sticklebacks is consistent between contexts.

348 citations

Journal ArticleDOI
TL;DR: The challenge for the future is to further develop the understanding of the relationship between the competitive environment and the responses of fishes, particularly with closer co-operation between empiricists and theoreticians, and to apply this knowledge to aquaculture and to better management of exploited fish stocks.
Abstract: Intraspecific food competition exerts powerful selective forces on all animals; successful foragers thrive relative to weaker conspecifics. Understanding competition is therefore fundamental both to ecological insight and to conservation efforts. Fish are adaptable and tractable experimental organisms, offering excellent model systems for studies on competition, and they lend themselves to two approaches: (i) studies of short-term competition, which quantify the components of behavioural interactions; (ii) studies of long-term interactions, in which the indeterminate nature of fish growth makes it possible to measure rates directly and correlate them with competitive success. The nature and the intensity of competition vary according to resource characteristics and distributions in time and space, the ecological context, and the relative competitive abilities of the foragers. Second-order effects, such as winner and loser consequences, add to the complexity and frustrated early attempts to develop realistic models of intraspecific competition. Recently, however, considerable advances have been made in both laboratory and field studies on fishes adding to our understanding of these interacting effects. At the same time, the application of individual-based modelling offers the prospect of progress towards greater realism and accuracy in predicting competitive outcomes. This review draws together a wide and disparate literature on intraspecific competition in fishes to facilitate the work of both empiricists and theoreticians towards these important goals. In the short term, competing individuals may adopt different behavioural strategies and feeding patterns or establish dominance hierarchies and feeding territories. In the longer term, competition can drive character displacement and the formation of species pairs and fish provide some of the most compelling examples of these processes in evolutionary biology. The challenge for the future is to further develop our understanding of the relationship between the competitive environment and the responses of fishes, particularly with closer co-operation between empiricists and theoreticians, and to apply this knowledge to aquaculture and to better management of exploited fish stocks.

254 citations

Book
01 Jan 2002
TL;DR: The Human Dimension of Fisheries Science: (P. J. Reynolds, N. Dulvy And C. Roberts) uncovers the human dimension of fisheries science as well as the science and management of fisheries, and some of the aspects of management and ecology that have changed over time.
Abstract: Volume 1: Fish Biology. 1. Banishing Ignorance: Underpinning Fisheries with Basic Biology (P. J. B. Hart and J. D. Reynolds). 2. Phylogeny and Systematics of Fishes (A. C. Gill and R.D. Mooi). 3. Historical Biogeography of Fishes (R. D. Mooi and A. C. Gill). 4. The Physiology of Living in Water (O. Brix). 5. Environmental Factors and Rates of Development and Growth (M. Jobling). 6. Recruitment: Understanding Density--dependence in Fish Populations (R. A. Myers). 7. Life Histories of Fish (J. A. Hutchings). 8. Migration (J. Metcalfe, G. Arnold and R. McDowall). 9. Genetics of Fish Populations (R. D. Ward). 10. Behavioural Ecology of Reproduction in Fish (E. Forsgren, J. D. Reynolds and A. Berglund). 11. Fish Foraging and Habitat Choice: A Theoretical Perspective (G. G. Mittelbach). 12. Feeding Ecology of Piscivorous Fishes (F. Juanes, J. A. Buckel and F. S. Scharf). 13. Fish as Prey (J. Krause, E. M. A. Hensor and G. D. Ruxton). 14. Trophic Ecology and the Structure of Marine Food Webs (N. V.C. Polunin and J.K. Pinnegar). 15. Community Ecology of Freshwater Fishes (L. Persson). 16. Comparative Ecology of Marine Fish Communities (K. Martha M. Jones, D. G. Fitzgerald and P. F. Sale). 17. Interactions Between Fish, Parasites and Disease (I. Barber and R. Poulin). Volume 2: Fisheries. 1. The Human Dimension Of Fisheries Science: (P. J. B. Hart And J. D. Reynolds). 2. Fish Capture Devices In Industrial And Artisanal Fisheries And Their Influence On Management (O. A. Misund, J. Kolding and P. Freon). 3. Marketing Fish (J. A. Young And J. F. Muir). 4. A History Of Fisheries And Their Science And Management (T. D. Smith). 5. Gathering Data For Resource Monitoring And Fisheries Management (D. Evans and R. Grainger). 6. Surplus Production Models (J. T. Schnute And L. Richards). 7. Dynamic Pool Models I: Interpreting The Past Using Virtual Population Analysis (J. G. Shepherd And J. G. Pope). 8. Dynamic Pool Models II: Short--Term And Long--Term Forecasts Of Catch And Biomass (J. G. Shepherd And J. G. Pope). 9. A Bumpy Old Road: Size--Based Methods In Fisheries Assessment (T. J. Pitcher). 10. Ecosystem Models (D. Pauly And V. Christensen). 11. Individual--Based Models (G. Huse, J. Giske And A. G. V. Salvanes). 12. The Economics Of Fisheries (R. Hannesson). 13. Choosing The Best Model For Fisheries Assessment (P. Sparre And P. J. B. Hart). 14. Marine Protected Areas, Fish And Fisheries (N. V. C. Polunin). 15. Exploitation And Other Threats To Fish Conservation (J. D. Reynolds, N. K. Dulvy And C. M. Roberts). 16. Ecosystem Effects Of Fishing (M. J. Kaiser And S. Jennings). 17. Recreational Fishing (I. G. Cowx)

244 citations

BookDOI
01 Jan 2007
TL;DR: Pitcher et al. as discussed by the authors proposed a quantitative evaluation framework and trophic signature for seamount food webs for the purpose of evaluating seamount ecology, fisheries and conservation.
Abstract: 1 Seamount characteristics Paul Wessel 2 How many seamounts are there and where are they located? Adrian Kitchingman, Sherman Lai, Telmo Morato and Daniel Pauly 3 A history of seamount research Paul E Brewin, Karen I Stocks and Gui Menezes 4 Physical processes and seamount productivity Martin White, Igor Bashmachnikov, Javier Aristegui and Ana Martins 5 Seamount plankton dynamics Amatzia Genin and John F Dower 6 Midwater fish assemblages and seamounts Filipe M Porteiro and Tracey Sutton 7 Seamount benthos Sarah Samadi, Thomas Schlacher and Bertrand Richer de Forges 8 Corals on seamounts Alex D Rogers, A Baco, H Griffiths, T Hart and Jason M Hall-Spencer 9 Seamount fishes: ecology and life histories Telmo Morato and Malcolm R Clark 10 Fish visitors to seamounts Section A: Tunas and billfish at seamounts Kim N Holland and R Dean Grubbs Section B: Aggregations of large pelagic sharks above seamounts Feodor Litvinov 11 Seamounts and cephalopods Malcolm Clarke 12 Air-breathing visitors to seamounts Section A: Marine mammals Kristin Kaschner Section B: Sea turtles Marco A Santos, Alan B Bolten, Helen R Martins, Brian Riewald and Karen A Bjorndal Section C: Importance of seamounts to seabirds David R Thompson 13 Biogeography and biodiversity of seamounts Karen I Stocks and Paul JB Hart 14 Raiding the larder: a quantitative evaluation framework and trophic signature for seamount food webs Tony J Pitcher and Cathy Bulman 15 Modelling seamount ecosystems and their fisheries Beth Fulton, Telmo Morato and Tony J Pitcher 16 Small-scale fishing on seamounts Helder Marques da Silva and Mario Rui Pinho 17 Large-scale distant-water trawl fisheries on seamounts Malcolm R Clark, Vladimir I Vinnichenko, John DM Gordon, Georgy Z Beck-Bulat, Nikolai N Kukharev and Alexander F Kakora 18 Catches from world seamount fisheries Reg Watson, Adrian Kitchingman and William Cheung 19 Impacts of fisheries on seamounts Malcolm R Clark and J Anthony Koslow 20 Management and conservation of seamounts P Keith Probert, Sabine Christiansen, Kristina M Gjerde, Susan Gubbay and Ricardo S Santos 21 The depths of ignorance: an ecosystem evaluation framework for seamount ecology, fisheries and conservation Tony J Pitcher, Telmo Morato, Paul JB Hart, Malcolm R Clark, Nigel Haggan and Ricardo S Santos

225 citations


Cited by
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Journal ArticleDOI
TL;DR: Preface to the Princeton Landmarks in Biology Edition vii Preface xi Symbols used xiii 1.
Abstract: Preface to the Princeton Landmarks in Biology Edition vii Preface xi Symbols Used xiii 1. The Importance of Islands 3 2. Area and Number of Speicies 8 3. Further Explanations of the Area-Diversity Pattern 19 4. The Strategy of Colonization 68 5. Invasibility and the Variable Niche 94 6. Stepping Stones and Biotic Exchange 123 7. Evolutionary Changes Following Colonization 145 8. Prospect 181 Glossary 185 References 193 Index 201

14,171 citations

Journal Article
TL;DR: For the next few weeks the course is going to be exploring a field that’s actually older than classical population genetics, although the approach it’ll be taking to it involves the use of population genetic machinery.
Abstract: So far in this course we have dealt entirely with the evolution of characters that are controlled by simple Mendelian inheritance at a single locus. There are notes on the course website about gametic disequilibrium and how allele frequencies change at two loci simultaneously, but we didn’t discuss them. In every example we’ve considered we’ve imagined that we could understand something about evolution by examining the evolution of a single gene. That’s the domain of classical population genetics. For the next few weeks we’re going to be exploring a field that’s actually older than classical population genetics, although the approach we’ll be taking to it involves the use of population genetic machinery. If you know a little about the history of evolutionary biology, you may know that after the rediscovery of Mendel’s work in 1900 there was a heated debate between the “biometricians” (e.g., Galton and Pearson) and the “Mendelians” (e.g., de Vries, Correns, Bateson, and Morgan). Biometricians asserted that the really important variation in evolution didn’t follow Mendelian rules. Height, weight, skin color, and similar traits seemed to

9,847 citations

Journal ArticleDOI
28 Mar 2002-Nature
TL;DR: A review of the ecological impacts of recent climate change exposes a coherent pattern of ecological change across systems, from polar terrestrial to tropical marine environments.
Abstract: There is now ample evidence of the ecological impacts of recent climate change, from polar terrestrial to tropical marine environments. The responses of both flora and fauna span an array of ecosystems and organizational hierarchies, from the species to the community levels. Despite continued uncertainty as to community and ecosystem trajectories under global change, our review exposes a coherent pattern of ecological change across systems. Although we are only at an early stage in the projected trends of global warming, ecological responses to recent climate change are already clearly visible.

9,369 citations

Journal Article
TL;DR: Prospect Theory led cognitive psychology in a new direction that began to uncover other human biases in thinking that are probably not learned but are part of the authors' brain’s wiring.
Abstract: In 1974 an article appeared in Science magazine with the dry-sounding title “Judgment Under Uncertainty: Heuristics and Biases” by a pair of psychologists who were not well known outside their discipline of decision theory. In it Amos Tversky and Daniel Kahneman introduced the world to Prospect Theory, which mapped out how humans actually behave when faced with decisions about gains and losses, in contrast to how economists assumed that people behave. Prospect Theory turned Economics on its head by demonstrating through a series of ingenious experiments that people are much more concerned with losses than they are with gains, and that framing a choice from one perspective or the other will result in decisions that are exactly the opposite of each other, even if the outcomes are monetarily the same. Prospect Theory led cognitive psychology in a new direction that began to uncover other human biases in thinking that are probably not learned but are part of our brain’s wiring.

4,351 citations

Journal ArticleDOI
03 Nov 2006-Science
TL;DR: The authors analyzed local experiments, long-term regional time series, and global fisheries data to test how biodiversity loss affects marine ecosystem services across temporal and spatial scales, concluding that marine biodiversity loss is increasingly impairing the ocean's capacity to provide food, maintain water quality, and recover from perturbations.
Abstract: Human-dominated marine ecosystems are experiencing accelerating loss of populations and species, with largely unknown consequences. We analyzed local experiments, long-term regional time series, and global fisheries data to test how biodiversity loss affects marine ecosystem services across temporal and spatial scales. Overall, rates of resource collapse increased and recovery potential, stability, and water quality decreased exponentially with declining diversity. Restoration of biodiversity, in contrast, increased productivity fourfold and decreased variability by 21%, on average. We conclude that marine biodiversity loss is increasingly impairing the ocean's capacity to provide food, maintain water quality, and recover from perturbations. Yet available data suggest that at this point, these trends are still reversible.

3,672 citations