Comparing interactive and automated mapping systems for supporting fisheries enforcement activities—a case study on vessel monitoring systems (VMS)

The conservation of wild fisheries resources in the face of an ever-increasing world demand for seafood requires the use of a number of management tools, including no-take zones, and gear, species, and temporal restrictions. One way of enforcing some of these regulations is through the use of Vessel Monitoring System (VMS) data that provides enforcement officers with the position of fishing vessels in the management area. The increasing volume of movement data collected using VMS calls for new methods that could help analysts extract useful knowledge from these large data sets. Various approaches have been proposed for visualizing and exploring movement data and detecting patterns within these data, but those approaches have generally not been tested in a real-world context or compared together, making their actual usability and utility unclear. This paper describes, compares, and assesses three such approaches in the context of fisheries enforcement: an existing system used for fisheries enforcement operations in Canada (VUE), a novel Hybrid Spatio-temporal Filtering (HSF) system developed by the authors, and an automated Behavioural Change Point Analysis (BCPA) system. A field trial was conducted with experienced fisheries enforcement officers to compare and contrast the benefits and drawbacks of the three approaches. While all three presented advantages and disadvantages, the interactivity of VUE and HSF were identified as desirable features, as they provide analysts with more control over the data, while allowing flexible data exploration. BCPA, while providing an automated approach to the data analysis, was pointed out as being too much of a “black box”, causing unease among the experts who require a level of transparency similar to that of legally admissible evidence. In the end, the experts suggested that the best approach would be to merge the analytical power of their existing VUE system with the exploratory power of the HSF system. This study provides insight into the value of using interactive mapping and filtering approaches in support of data analysis in the context of fisheries enforcement.     

Viewer preference for spatial arrangement of park trees: An application of video-imaging technology

Research on perception of parks and recreation settings has examined several important tree attributes that influence people's visual preferences. This research, however, has usually not considered the spatial arrangement of the trees, partly because of the lack of adequate methods for representing tree arrangements with systematically manipulated geometries. In the study reported here, computer video-imaging techniques were used to construct simulated landscape scenes that varied on specific dimensions of the spatial configuration of trees. The simulations were rated for visual preference by three respondent groups: a university class, a bicycle club, and a women's civic group. Preference ratings were significantly influenced by the number of trees in the scene, by the number of clumps into which trees were grouped, and by the diameter of the clumps. The video-imaging technology implemented in this study offers important methodological advantages for the design of carefully controlled experiments to study human response to variation in landscape treatments.     

Boater preferences for beach characteristics downstream from Glen Canyon Dam, Arizona

Release flow decisions are increasingly being influenced by an array of social values, including those related to river-based recreation. A substantial portion of past recreation research on downstream impacts of dams has focused on variability of instream flows. This study complements past research by assessing user preferences for beach characteristics affected by long-term impacts of flow regimes. Based upon a study of three recreational user groups (private trip leaders, commercial passengers, and river guides) of the Colorado River in Grand Canyon, preferences for beach size, presence of shade on beach, and presence of vegetation on beach are examined. Results indicate that large size beaches with shade from trees are setting characteristics with highly reliable and strong user preferences. The multinomial regression models developed for each user group indicate that 80% of all respondents would choose beach campsites 800 m(2); results were the same regardless of respondents' past boating experience, boat type (i.e. oar or motorized), or group size. In addition, size of beach was consistently reported to be a trip feature of moderate importance to respondents' river trip. Implications of this research are related to future prospects for controlled floods (i.e. spike flows) released from Glen Canyon Dam.