Trevor J. Willis

Trevor J. Willis
Stazione Zoologica Anton Dohrn | Stazione Zoologica · Integrative Marine Ecology

PhD University of Auckland

About

73
Publications
62,733
Reads
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7,904
Citations
Citations since 2016
22 Research Items
4277 Citations
20162017201820192020202120220100200300400500600
20162017201820192020202120220100200300400500600
20162017201820192020202120220100200300400500600
20162017201820192020202120220100200300400500600
Introduction
Trevor J. Willis currently works for the Stazione Zoologica Anton Dohrn at the Fano Marine Centre, based in Fano, Italy.
Additional affiliations
September 2019 - present
Stazione Zoologica Anton Dohrn
Position
  • Research Director
April 2012 - July 2019
University of Portsmouth
Position
  • Professor (Associate)
January 2007 - April 2012
National Institute of Water and Atmospheric Research
Position
  • Senior Researcher
Education
January 1995 - December 2000
University of Auckland
Field of study
  • Biology

Publications

Publications (73)
Article
Full-text available
Predation occurs when an organism completely or partially consumes its prey. Partial consumption is typical of herbivores but is also common in some marine microbenthic carnivores that feed on colonial organisms. Associations between nudibranch molluscs and colonial hydroids have long been assumed to be simple predator-prey relationships. Here we s...
Article
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of energy fluxes in marine animal forests of the Anthropocene: factors shaping the future seascape. Climate change is already transforming the seascapes of our oceans by changing the energy availability and the metabolic rates of the organisms. Among the ecosystem-engineering species that structure the seascape, marine animal forests (MAFs) are the...
Article
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We document from a sediment core collected at 23 m water depth offshore of Separation Point on the northern coast of Aotearoa New Zealand's South Island, 3000 years of natural and human-induced change to undisturbed offshore sediments that are protected from contact fishing methods. Multivariate analysis of sediment characteristics and sources of p...
Article
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Microplastics are recognised as a potential global threat to marine ecosystems, but the biological mechanisms determining their impact on marine life are still largely unknown. Here, we investigated the effects of microplastics on the red coral, a long-lived habitat-forming organism belonging to the Corallium genus, which is present at almost all l...
Article
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The application of stable isotope analysis (SIA) is increasing in elasmobranch trophic ecology, but inconsistency remains in terms of the tissue pre-treatment methods chosen to remove biases introduced by lipids and urea. SIA of a range of non-lethally extracted tissues from a diverse group of elasmobranchs, including mesopredators, is increasing,...
Article
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Motivation: The BioTIME database contains raw data on species identities and abundances in ecological assemblages through time. These data enable users to calculate temporal trends in biodiversity within and amongst assemblages using a broad range of metrics. BioTIME is being developed as a community-led open-source database of biodiversity time se...
Article
Full-text available
Motivation: The BioTIME database contains raw data on species identities and abundances in ecological assemblages through time. These data enable users to calculate temporal trends in biodiversity within and amongst assemblages using a broad range of metrics. BioTIME is being developed as a community-led open-source database of biodiversity time se...
Article
Full-text available
Motivation: The BioTIME database contains raw data on species identities and abundances in ecological assemblages through time. These data enable users to calculate temporal trends in biodiversity within and amongst assemblages using a broad range of metrics. BioTIME is being developed as a community led open-source database of biodiversity time se...
Article
The paper evaluates the potential consumers’ response from the United Kingdom and Denmark to the introduction of certification for the sustainability and quality of seafood products. Broadly speaking, it was found that consumers were willing to pay a price premium for and buy more of hypothetically labelled products. Fifteen years on, drawing on th...
Article
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Marine Protected Areas (MPAs) offer a unique opportunity to test the assumption that fishing pressure affects some trophic groups more than others. Removal of larger predators through fishing is often suggested to have positive flow-on effects for some lower trophic groups, in which case protection from fishing should result in suppression of lower...
Conference Paper
Baited remote underwater video systems (BUV) collect spatial and temporal patterns of abundance, size and fish assemblage composition of various species. They were developed from the original concept of time-lapse still photography used to assess fish assemblages in the deep sea. In the late 1990's, the system was adapted as a shallow water system...
Article
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A total of 17 species from the families Styelidae, Polyclinidae, Polycitoridae, Pseudodistomidae, Ritterellidae and Didemnidae are described for the first time in collections from remote fiords with steep-sided walls, high rainfall and high tidal flow on the south-west coast of New Zealand. The Fiordland ascidian assemblages are composed of endemic...
Article
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Evaluating the effects of marine reserves on exploited species can be challenging because they occur within a context of natural spatial and temporal variation at many scales. For rigorous inferences to be made, such evaluations require monitoring programmes that are replicated at appropriate scales. We analysed monitoring data of snapper Pagrus au...
Article
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In line with global targets agreed under the Convention on Biological Diversity, the number of marine protected areas (MPAs) is increasing rapidly, yet socio-economic benefits generated by MPAs remain difficult to predict and under debate1, 2. MPAs often fail to reach their full potential as a consequence of factors such as illegal harvesting, regu...
Article
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New Zealand’s ‘Marine Protected Areas Policy’ is currently being implemented, and requires background information concerning the scientific and biodiversity values of marine reserves. This review determines the current state of knowledge, discusses the value of marine reserves for scientific research and biodiversity conservation, assesses trends i...
Article
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Species richness has dominated our view of global biodiversity patterns for centuries. The dominance of this paradigm is reflected in the focus by ecologists and conservation managers on richness and associated occurrence-based measures for understanding drivers of broad-scale diversity patterns and as a biological basis for management. However, th...
Article
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Common bottlenose dolphins, Tursiops truncatus, were surveyed in offshore gas fields off Ravenna, Italy, between Spring and Autumn, 2001–2005. These visual surveys provide the first density estimates of bottlenose dolphins in the Northwestern Adriatic Sea south of the Po River. Since no study has examined the distribution of bottlenose dolphins relat...
Article
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Using non-lethal tissue sampling for stable isotope analysis has become standard in many fields, but not for fishes, despite being desirable when species are rare or protected, when repeated sampling of individuals is required or where removal may bias other analyses. Here, we examine the utility of fish dorsal fin membrane as an alternative to mus...
Article
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The scientific literature (including some of the most high-profile papers) on the ecological and fisheries effects of permanent, no-take marine reserves is dominated by examples from tropical regions. It appears to have been tacitly assumed that inference from these studies can be directly transferred to guide expectations about the effects of mari...
Technical Report
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Baited underwater video surveys within designated management zones of Milford Sound and the Doubtful Sound complex found low numbers of blue cod and tarakihi. Densities of both species tended to be higher at fiord entrances and on the open coast than inside fiords despite these areas being open to fishing. Low abundance of blue cod meant that the s...
Article
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On coasts with high tidal ranges, fishes regularly establish linkages between subtidal and intertidal habitats via tidal movements, such that the home range incorporates habitat that is only intermittently available. To examine the responses of shallow-water reef fish assemblages to tidal water level changes in a macrotidal area of the tropical eas...
Article
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Community-based natural resource management (CBNRM) has been a pervasive paradigm in conservation circles for three decades. Despite many potentially attractive attributes it has been extensively critiqued from both ecological and sociological perspectives with respect to theory and practice (for example Leach et al. 1999; Berkes 2004; Fabricius et...
Article
Beta diversity measures the variability in species composition, and Whittaker's index has become the most widely used measure of P-diversity. However, on soft bottom benthic assemblages Whittaker's index is heavily influenced by the number of species recorded in a single sample (defined as rare species). This over-weighting of rare species induces...
Article
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The structure of cryptic reef fish assemblages was assessed on sheltered and exposed aspects of coastal breakwaters at two locations in the northwestern Adriatic Sea. There were distinct differences between the two levels of exposure, which were consistent between locations. Habitat characteristics, measured on scales of tens of centimetres, explai...
Article
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It seems widely accepted that environmental conservation will develop in the right direction only through dialogue across disciplines that is well sourced and objectively argued. Yet most people seem to have different ideas about what constitutes interdisciplinarity and few if any have a clear idea as to how different disciplines should be effectiv...
Article
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Studies of reef fish assemblages in space rarely consider the effects of temporal variability on spatial comparisons, and when they do, usually examine timescales of months to years. The nature of fish monitoring surveys is such that particular locations may be surveyed at one time of day, and surveys designed to establish the degree of spatial var...
Article
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Wildlife feeding has become an integral part of the range of activities offered to protected area visitors. In marine protected areas (MPAs), fish feeding may cause changes in the behavior, and thus the density and distribution, of coastal fish species. We evaluated spatial variability in human-positive fish behavior around the Ustica Island MPA (I...
Article
The Politics of Fisheries in the European UnionBY CHRISTIAN LEQUESNE xi +170 pp., 24 × 16 × 1.5 cm, ISBN 0 7190 6770 7 hardback, GB£50.00, Manchester, UK: Manchester University Press, 2004 - - Volume 32 Issue 4 - TREVOR J. WILLIS
Article
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The proportion of a fish stock that is killed by fishing activity is often calculated as the catch divided by the estimated stock biomass. However, stock biomass is notoriously difficult to estimate reliably, and moreover, the catch may be uncertain or misreported and does not include losses due to discarding. In all too many fisheries, these diffi...
Conference Paper
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A structured hierarchical sampling design, using a modified visual census technique, was applied to observe cryptic fishes on coastal defence structures in the North Adriatic Sea. Two locations, Cesenatico and Casal Borsetti, were randomly selected in the North Adriatic Sea. In each of these locations three breakwaters were selected. Both the seawa...
Article
This study assessed the efficacy of bath administrations of Aqui-S, formalin and praziquantel against adults and eggs of Benedenia seriolae and Zeuxapta seriolae, two monogenean ectoparasites of kingfish (Seriola lalandi lalandi). Our results showed that 2.5 ppm praziquantel administered for either 24 or 48 h was the most effective treatment for re...
Article
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This study reports the response of snapper Pagrus auratus to the establishment of no-take status in a marine reserve around the Poor Knights Islands in northeastern New Zealand. The Poor Knights and 2 reference locations, Cape Brett and the Mokohinau Islands, were sampled biannually for 4 yr using baited underwater video (BUV). Following the implem...
Article
Handbook of Fish Biology and Fisheries (two volume set)EDITED BY PAUL J. B. HART AND JOHN D. REYNOLDS856 pp., 25 × 19 × 2.5 cm, ISBN 0 632 06483 8 hardback, GB£ 130.00, Oxford, UK: Blackwell Science Ltd, 2002 - - Volume 30 Issue 4 - Trevor J. Willis
Article
Full-text available
The home-range size and location of reef-associated snapper Pagrus auratus: Sparidae were investigated by use of a radio acoustic-positioning telemetry (RAPT) system. Tags were surgically implanted in 5 snapper that were subsequently monitored every minute for a period of 5 mo, and then intermittently over another 7 mo. Site fidelity was high among...
Article
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The responses of demersal reef fish to the establishment of the Poor Knights Islands Marine Reserve in northeastern New Zealand were investigated. The reserve and two reference locations (Cape Brett and the Mokohinau Islands) were sampled biannually over 3½ years using two survey methods: baited underwater video (BUV), and underwater visual census...
Article
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Cryptic fish assemblages on temperate rocky reefs in New Zealand are among the most diverse in the world, yet very little is known regarding ecological processes that may affect their density and diversity. The potential effects of reef structural complexity, kelp density, and the increased density of predatory fish on assemblages of small, cryptic...
Article
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An extensive literature has appeared since 1990, based on the study of ‘no-take’ marine reserves and their potential to make significant contributions both to conservation and the management of fisheries, especially in tropical environments (e.g. Polunin 1990; Roberts & Polunin 1991; DeMartini 1993; Roberts 1997; Allison et al. 1998; Guénette et al...
Article
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An open access copy of this article is available from the publishers website. The prevalence and intensity of metazoan ectoparasites on the skin and gills of kingfish, Seriola lalandi lalandi (Carangidae), collected from White Island (n = 32), Ranfurly Banks (n = 7), and Three Kings Islands (n = 7), is reported. Kingfish were host to two monogenean...
Article
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1. The use of marine reserves as tools either for conservation or fisheries management requires rigorous empirical evidence for the recovery of exploited species within them. 2. The relative density and size structure of snapper Pagrus auratus (Sparidae), an intensively exploited reef fish species, were measured, using baited underwater video, insi...
Article
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A flexible method is needed for constrained ordination on the basis of any distance or dissimilarity measure, which will display a cloud of multivariate points by reference to a specific a priori hypothesis.We suggest the use of principal coordinate analysis (PCO, metric MDS), followed by either a canonical discriminant analysis (CDA, when the hypo...
Article
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The diversity and density of small, benthic reef fishes were estimated using visual census and enclosed rotenone stations, Visual census Underestimated the number of species present and the density of common species by up to 91%. (C) 2001 The Fisheries Society of the British Isles.
Article
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An open access copy of this article is available from the publishers website. Increases in the density of exploited species on unfished reefs logically implies that some individuals are at least temporarily resident, or show fidelity to a particular area. We tagged snapper (Pagrus auratus (Bloch & Schneider 1801)) in the Leigh Marine Reserve, New Z...
Article
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In longline fisheries, decreasing the catch of undersized fish and minimizing the rate of gut-hooking over all sizes will reduce incidental mortality, and improve the landed value of the commercial catch. In this study, standard Tainawa 16R longline hooks were simultaneously fished for snapper (Pagrus auratus) with the same hook pattern modified by...
Article
Thesis (PhD--Biological Sciences)--University of Auckland, 2001.
Article
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Estimates of the relative density of fishes form the basis of many marine ecological studies as well as the assessment of effects of fishing or pollution. Plasticity in the behavioural response of large reef fishes to SCUBA divers means that commonly used underwater visual census (UVC) techniques do not always provide reliable estimates of relative...
Article
Full-text available
The ability to make accurate estimates of fish relative abundance is the basis of both ecological and environmental effects studies, and flawed sampling methods may give misleading results even in otherwise well-designed surveys. This paper compares surveys of snapper Pagrus auratus (Sparidae) and blue cod Parapercis colias (Pinguipedidae) conducte...