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Combining state-of-the art digital imaging technology with different kinds of marine exploration techniques such as modern autonomous underwater vehicle (AUV), remote operating vehicle (ROV) or other monitoring platforms enables marine imaging on new spatial and/or temporal scales. A comprehensive interpretation of such image collections requires the detection, classification and quantification of objects of interest (OOI) in the images usually performed by domain experts. However, the data volume and the rich content of the images makes the support by software tools inevitable. We define some requirements for marine image annotation and present our new online tool BIIGLE 2.0. It is developed with a special focus on annotating benthic fauna in marine image collections with tools customized to increase efficiency and effectiveness in the manual annotation process. The software architecture of the system is described and the special features of BIIGLE 2.0 are illustrated with different use-cases and future developments are discussed.

Herbivorous fishes play a critical role in maintaining or disrupting the ecological resilience of many kelp forests, coral reefs and seagrass ecosystems, worldwide. The increasing rate and scale of benthic habitat loss under global change has magnified the importance of herbivores and highlights the need to study marine herbivory at ecologically relevant scales. Currently, underwater herbivore exclusions (or inclusions) have been restricted to small scale experimental plots, in large part due to the challenges of designing structures that can withstand the physical forces of waves and currents, without drastically altering the physical environment inside the exclusion area. We tested the ability of bubble curtains to deter herbivorous fishes from feeding on seaweeds as an alternative to the use of rigid exclusion cages. Kelps (Ecklonia radiata) were transplanted onto reefs with high browsing herbivore pressure into either unprotected plots, exclusion cages or plots protected by bubble curtains of 0.785 m2 and 3.14 m2. Remote underwater video was used to compare the behavioral response of fishes to kelps protected and unprotected by bubble curtains. Kelp biomass loss was significantly lower inside the bubble curtains compared to unprotected kelps and did not differ from kelp loss rates in traditional exclusion cages. Consistent with this finding, no herbivorous fishes were observed entering into the bubble curtain at any point during the experiment. In contrast, fish bite rates on unprotected kelps were 1,621 ± 702 bites h−1 (mean ± SE). Our study provides initial evidence that bubble curtains can exclude herbivorous fishes, paving the way for future studies to examine their application at larger spatial and temporal scales, beyond what has been previously feasible using traditional exclusion cages.

The fluorescence of many marine organisms is a visually compelling phenomenon. Descriptions of the phenomenon have at times been accompanied by suggestions of a visual function, but with minimal supporting evidence. It is possible to make quantitative estimates of the contribution of fluorescence emission to a visual signal under arbitrary illumination conditions. This analysis can help in deciding whether further research into a visual function is warranted, or whether the fluorescence is an interesting epiphenomenon associated with biomaterials that are present for other purposes. This paper describes the concepts associated with visual signals consisting of both reflected and fluoresced light, and methods for determining the underlying optical properties and using that information to model visual signal under environmentally relevant illumination conditions.

This paper fulfils a gap in environmental management by producing a typology of stakeholders for effective participatory processes and co-design of solutions to complex social–environmental issues and then uses this typology for a stepwise roadmap methodology for balanced and productive stakeholder engagement. Definitions are given of terminology that is frequently used interchangeably such as “stakeholders,” “social actors,” and “interested parties.” Whilst this analysis comes from a marine perspective, it is relevant to all environments and the means of tackling environmental problems. Eleven research questions about participative processes are addressed, based on more than 30 years of experience in water, estuarine, coastal, and marine management. A stepwise roadmap, supported by illustrative tables based on case-studies, shows how a balanced stakeholder selection and real engagement may be achieved. The paper brings these together in the context of several up-to-date concepts such as complex, nested governance, the 10 tenets for integrated, successful, and sustainable marine management, the System Approach Framework and the evolution of DPSIR into DAPSI(W)R(M) framework. Examples given are based on the implementation of the Marine Strategy Framework Directive, the Water Framework Directive, the Environmental Impact Assessment Directive, the Framework Directive for Maritime Spatial Planning, as well as for Regional Sea Conventions. The paper also shows how tools that have been developed in recent projects can be put to use to implement policy and maximize the effectiveness of stakeholder participation.

Analysis of visible remote sensing data research requires removing atmospheric effects by conversion from radiance to at-surface reflectance. This conversion can be achieved through theoretical radiative transfer models, which yield good results when well-constrained by field observations, although these measurements are often lacking. Additionally, radiative transfer models often perform poorly in marine or lacustrine settings or when complex air masses with variable aerosols are present. The empirical line method (ELM) measures reference targets of known reflectance in the scene. ELM methods require minimal environmental observations and are conceptually simple. However, calibration coefficients are unique to the image containing the reflectance reference. Here we compare the conversion of hyperspectral radiance observations obtained with the NASA Glenn Research Center Hyperspectral Imager to at-surface reflectance factor using two reflectance reference targets. The first target employs spherical convex mirrors, deployed on the water surface to reflect ambient direct solar and hemispherical sky irradiance to the sensor. We calculate the mirror gain using near concurrent at-sensor reflectance, integrated mirror radiance, and in situ water reflectance. The second target is the Lambertian-like blacktop surface at Maumee Bay State Park, Oregon, OH, where reflectance was measured concurrently by a downward looking, spectroradiometer on the ground, the aerial hyperspectral imager and an upward looking spectroradiometer on the aircraft. These methods allows us to produce an independently calibrated at-surface water reflectance spectrum, when atmospheric conditions are consistent. We compare the mirror and blacktop-corrected spectra to the in situ water reflectance, and find good agreement between methods. The blacktop method can be applied to all scenes, while the mirror calibration method, based on direct observation of the light illuminating the scene validates the results. The two methods are complementary and a powerful evaluation of the quality of atmospheric correction over extended areas. We decompose the resulting spectra using varimax-rotated, principal component analysis, yielding information about the underlying color producing agents that contribute to the observed reflectance factor scene, identifying several spectrally and spatially distinct mixtures of algae, cyanobacteria, illite, haematite, and goethite. These results have implications for future hyperspectral remote sensing missions, such as PACE, HyspIRI, and GeoCAPE.

The poorly understood movements of sea turtles during the “lost years” of their early life history have been characterized as a “passive drifter” stage. Biologging technology allows us to study patterns of dispersal, but the small body size of young life stages requires particular consideration that such tagging does not significantly impede animal movements. We tested the effect of instrument attachment methods for mobile acoustic tracking of hatchling sea turtles, including a design that would be suitable for leatherback turtles (Dermochelys coriacea). We obtained 8-week-old hatchery-reared green sea turtles (Chelonia mydas) (n = 12 individuals) and examined the effect of attaching Vemco V5 acoustic tags. Each animal's swim speed, swimming depth, and stroke frequency were determined under three scenarios: control, direct Velcro® attachment to the carapace, and harness attachment, to determine if there was a significant difference amongst treatments. Turtle swimming speed was significantly slower during the middle period of the trial for the harness attachment compared with the control. No significant change in swim speed was observed when the tag was attached directly with Velcro®, and no significant change in dive depth was observed for either treatment compared to the control. Stroke frequency was significantly greater compared to the control at the end of the trial for the Velcro® attachment only, although there was no corresponding increase in swimming speed. This information can be used to design effective approaches for actively tracking free-ranging hatchling sea turtles to understand dispersal and survival of these vulnerable marine species.