Baited Remote Underwater Video (BRUV) has become a popular technique to survey fish assemblages for a wide range of purposes. BRUV methodology has, however, also varied greatly for a range of reasons. A major dichotomy occurs, in particular, in the time used to sample the fish assemblages i.e. the BRUV set time. The aim of this study was to determine whether differences in set time were likely to affect the conclusions reached by studies using different set times, and what might be the most appropriate and cost-effective set time to use to sample temperate reef fish assemblages. In this study, we test whether there were significant differences between the two main set times used (i.e. 30 and 60 min) in BRUV sampling for assemblage patterns, species diversity, and relative abundance of rocky reef fishes. In particular, we sampled fished and unfished rocky reefs to assess whether the different set times would lead to differences in the patterns or the interpretation of the subsequent data. We sampled fish assemblages on six rocky reefs (20–35 m) across two marine parks on the east coast of Australia. At each location replicate BRUVs were deployed for 30 and 60 min in a ‘no take’ area (marine sanctuary) and a fished area. The interpretations of the data across the fished and unfished zones were consistent with both set times indicating that the conclusions from both set time were comparable. Furthermore, there were no differences in fish assemblages or species richness between the set times. The relative abundances of the recreationally and commercially important snapper (Chrysophrys auratus) were greater in the longer set times, but the actual spatial patterns between zones and amongst locations were consistent. Piecewise regression analysis of the breakpoint times for species accumulation found that there were no significant differences between locations or between fished and unfished areas. Mean breakpoint, the time when species accumulation changes, occurred at 12 min ± 1.04 S.E. for all sites combined whilst the shorter set time was found to be less costly and require less field and laboratory times. This study quantifies that either 30 or 60 min will provide a reasonable estimate of rocky reef fish diversity and relative abundance for comparative purposes, on these shallow rocky reefs.
Catches in the groundfish hook and line fishery in British Columbia on Canada's west coast have been monitored since 2006 with an interrelated suite of technical components. These include, but are not limited to, full (100%) independent dockside monitoring, full video capture of fishing events and vessel monitoring at sea, 10% partial review of the video imagery from each trip, and full coverage of fisher logbooks. The monitoring also relies on complete retention of the over 30 species of rockfish (Sebastes spp.). Each component, in spite of its weaknesses as a stand-alone monitoring tool, makes an essential contribution without which the overall programme would fail. The programme has surpassed expectations in providing accurate, defensible, and timely estimates of total catch for all quota and many non-quota species. This document summarizes contextual and process ingredients, which contributed to implementation, the key being a “carrot and stick” approach wherein industry support was facilitated by the “carrot” of coincident full introduction of individual vessel quotas (ITQs). The “stick” was that Government support was conditional on improving catch monitoring with the proviso that ITQs would not be considered and the fishery would be closed until the monitoring was improved. Also important was the fact that previous failures to solve management and catch monitoring in this fishery with overly simple solutions had created an understanding by all participants that an effective and lasting solution would be complex and require a major commitment of time and funds.
- Marine ecosystems provide critically important goods and services to society, and hence their accelerated degradation underpins an urgent need to take rapid, ambitious and informed decisions regarding their conservation and management.
- The capacity, however, to generate the detailed field data required to inform conservation planning at appropriate scales is limited by time and resource consuming methods for collecting and analysing field data at the large scales required.
- The ‘Catlin Seaview Survey’, described here, introduces a novel framework for large-scale monitoring of coral reefs using high-definition underwater imagery collected using customized underwater vehicles in combination with computer vision and machine learning. This enables quantitative and geo-referenced outputs of coral reef features such as habitat types, benthic composition, and structural complexity (rugosity) to be generated across multiple kilometre-scale transects with a spatial resolution ranging from 2 to 6 m2.
- The novel application of technology described here has enormous potential to contribute to our understanding of coral reefs and associated impacts by underpinning management decisions with kilometre-scale measurements of reef health.
- Imagery datasets from an initial survey of 500 km of seascape are freely available through an online tool called the Catlin Global Reef Record. Outputs from the image analysis using the technologies described here will be updated on the online repository as work progresses on each dataset.
- Case studies illustrate the utility of outputs as well as their potential to link to information from remote sensing. The potential implications of the innovative technologies on marine resource management and conservation are also discussed, along with the accuracy and efficiency of the methodologies deployed.
Protected area management agencies are increasingly using management effectiveness evaluation (MEE) to better understand, learn from and improve conservation efforts around the globe. Outcome assessment is the final stage of MEE, where conservation outcomes are measured to determine whether management objectives are being achieved. When quantitative monitoring data are available, best-practice examples of outcome assessments demonstrate that data should be assessed against quantitative condition categories. Such assessments enable more transparent and repeatable integration of monitoring data into MEE, which can promote evidence-based management and improve public accountability and reporting. We interviewed key informants from marine protected area (MPA) management agencies to investigate how scientific data sources, especially long-term biological monitoring data, are currently informing conservation management. Our study revealed that even when long-term monitoring results are available, management agencies are not using them for quantitative condition assessment in MEE. Instead, many agencies conduct qualitative condition assessments, where monitoring results are interpreted using expert judgment only. Whilst we found substantial evidence for the use of long-term monitoring data in the evidence-based management of MPAs, MEE is rarely the sole mechanism that facilitates the knowledge transfer of scientific evidence to management action. This suggests that the first goal of MEE (to enable environmental accountability and reporting) is being achieved, but the second and arguably more important goal of facilitating evidence-based management is not. Given that many MEE approaches are in their infancy, recommendations are made to assist management agencies realize the full potential of long-term quantitative monitoring data for protected area evaluation and evidence-based management.