The thermal implications and ecological consequences of coloration in selected species : tenebrionid beetles (Onymacris bicolor and Onymacris ungui cularis), Cape gannets (Morus capensis) and Cape cormorants (Phalacrocorax capensis)

Bibliography: leaves 176-192.The thermal significance of coloration was investigated in two species of Namib Desert tenebrionid beetles and two species of marine birds. Body temperatures and heat fluxes of a black beetle (Onymacris unguicularis) and a beetle with white elytra (Onymacris bicolor) were compared in a wind tunnel in the laboratory. The effects of visible radiation, infrared radiation, conduction, convection, beetle colour and substratum colour on body temperature were analysed. Results showed that body colour has no overall effect on body temperature. Black elytra are warmed more by visible radiation, but colour is not relevant to heat loss by convection, or to heat flux between a beetle and a heated sand substratum, whether by emitted radiation or reflected visible radiation. 0. bicolor absorbs more heat by conduction and free convection from a heated substratum, but differences in shape between the two species may explain this effect. Combining the various modes of heat exchange to simulate natural conditions reveals that the extra heat absorbed by black elytra is readily dissipated by convection, and owing to the increased heating of white beetles from the substratum, heat fluxes between the two beetles balance. Body temperatures of dead and live beetles of both species were also measured in the field. Experiments were conducted on a hot sand substratum in the beetles' natural environment, under both visible (sunny) and infrared (shaded) conditions. Results supported the laboratory experiments, and showed that when temperature differences do occur between black and white beetles, these differences are generally less than 3.5 °C. These differences are small when compared with the ranges of body temperatures experienced by active beetles in the field (± 10 °C). In addition, these temperature differences occur only at low wind speeds (< 2 m s-1). Activity studies in the field showed that beetles choose to be active in high wind speeds, possibly because of the nature of their food source, which is wind-blown detritus. It is concluded that coloration does not have adaptive value in terms of the thermal biology of Namib Desert tenebrionid beetles. Physical properties of the plumages of white Cape gannets (Morus capensis) and black Cape cormorants (Phalacrocorax capensis ) were measured. Black plumages absorb more visible radiation than white plumages in still conditions. However, laboratory experiments with excised plumages showed that at wind speeds of 2 m s-1, cormorant plumages and skins were only 2-3 °C warmer than those of gannets. These differences disappeared at wind speeds of (< 2 m s-1). A biophysical heat transfer model predicted that in still, warm, sunny conditions, cormorants may gain up to 185 of their field metabolic rates, whereas gannets would gain only 42 . Field observations confirmed that nesting cormorants experience greater heat stress than gannets, even though cormorant nests occur in areas of lower micrometeorological temperatures. Cormorants begin to dissipate heat by evaporative water loss (i.e. pant) at lower environmental temperatures than gannets. The thermal consequence of coloration in these two species are that cormorants may have a lower cost of endothermy at temperatures below the thermoneutral zone, but may experience more heat stress during warm conditions; cormorants select cooler and windier nesting sites than gannets; and increased surf ace temperatures of black cormorant plumages may aid evaporative water loss from wet plumages, facilitating wing-drying. However, ptiloerection and wind may interact in the natural environment, negating the differential heating effects of coloration. It is concluded that the thermal implications of colour are negligible in both species, considering the temperate nature of their environment; Colour in both species is best explained by feeding ecology: white coloration is conspicuous to conspecifics and cryptic to prey in plunge divers (gannets), whereas black colour is cryptic to both conspecifics and prey in solitary swimmers (cormorants)

A systematic evaluation of the incremental protection of broad-scale habitats at Ningaloo Reef, Western Australia

Incremental increases to marine conservation areas in response to changing goals, 15 policy, threats or new information are common practice world-wide. Ningaloo Reef, in 16 north-western Australia, is protected by the Ningaloo Marine Park (State Waters) which 17 was expanded incrementally in 2004 so that 34% of the park now comprises no-take 18 sanctuary zones. To test the hypothesis that all habitats (benthic cover types) at 19 Ningaloo are actually protected at this 34% level, a systematic conservation planning 20 exercise was conducted using existing broad-scale habitat data (as a surrogate for 21 marine biodiversity) and C-Plan decision-support software. Though subtidal and 22 intertidal coral communities were found to be adequately protected, other habitats, 23 particularly those in deeper waters seaward of the reef did not attain the 34% target. 24 Efficient incremental additions to the sanctuary zones to allow increased representation 25 of these under-represented habitats were explored with C-Plan. It is recommended that 26 systematic conservation planning incorporating new biodiversity and social information 27 (now becoming available) be undertaken for the next iteration of the Ningaloo Marine 28 Park management plan. This analysis at Ningaloo Reef serves as a useful example of a 29 post-hoc systematic approach to guide incremental expansion of existing marine 30 protected areas in other parts of the world.http://www.publish.csiro.au/nid/126.htmab201

Local purse-seine fishers' economic losses owing to endangered seabird conservation measures – perceptions and reality

The likelihood of success of a marine protected area (MPA) is strongly dependent on stakeholders’ support. A concern often raised by local fishers is their lack of involvement in the design or management of a MPA and their loss of income owing to lost fishing grounds. We used Algoa Bay, South Africa, as a case study to analyse fisher’s and fish-processing factory managers’ concerns and perceived economic losses from fishing closures using structured interviews. Since 2009, a 20 km-radius purse-seine fishing-exclusion zone has been tested in Algoa Bay to assess the benefit to population recovery of the endangered African penguin Spheniscus demersus. Costs to the industry were estimated in terms of loss of catches and additional travel time to fishing grounds with and without closures. Fisher responses to interviews revealed general support for conservation and MPAs, but individuals interviewed did not feel that the 20 km fishing exclusion zones in Algoa Bay would aid African penguin conservation. While they systematically raised concerns about potential economic costs to their industry from closures, neither their catch sizes nor travel times varied significantly with fishing exclusion measures. Acknowledgement and assessment of the economic concerns may aid in initiating an informed dialogue amongst the various stakeholders in Algoa Bay, which may increase compliance and success of the newly proclaimed Addo elephant National Park MPA. Continued dialogue may also act as a catalyst for more integrated ocean management of biodiversity and human uses in the bay

Sex and size influence the spatiotemporal distribution of white sharks, with implications for interactions with fisheries and spatial management in the southwest Indian Ocean

The study was made possible through generous funding by Fischer Productions for fieldwork and equipment costs. TP was supported by a postdoctoral fellowship funded by the Nelson Mandela University Research Career Development Office (2016-2018) and funding from the South African Research Chairs Initiative awarded to Prof AT Lombard by the National Research Foundation, and by a Royal Society Newton International Fellowship (2018-2020, NF170682).Human activities in the oceans increase the extinction risk of marine megafauna. Interventions require an understanding of movement patterns and the spatiotemporal overlap with threats. We analysed the movement patterns of 33 white sharks (Carcharodon carcharias) satellite-tagged in South Africa between 2012 and 2014 to investigate the influence of size, sex and season on movement patterns and the spatial and temporal overlap with longline and gillnet fisheries and marine protected areas (MPAs). We used a hidden Markov model to identify ‘resident’ and ‘transient’ movement states and investigate the effect of covariates on the transition probabilities between states. A model with sex, total length and season had the most support. Tagged sharks were more likely to be in a resident state near the coast and a transient state away from the coast, while the probability of finding a shark in the transient state increased with size. White sharks moved across vast areas of the southwest Indian Ocean, emphasising the need for a regional management plan. White sharks overlapped with longline and gillnet fisheries within 25% of South Africa’s Exclusive Economic Zone and spent 15% of their time exposed to these fisheries during the study period. The demersal shark longline fishery had the highest relative spatial and temporal overlap, followed by the pelagic longline fishery and the KwaZulu-Natal (KZN) shark nets and drumlines. However, the KZN shark nets and drumlines reported the highest white shark catches, emphasising the need to combine shark movement and fishing effort with reliable catch records to assess risks to shark populations accurately. White shark exposure to shark nets and drumlines, by movement state, sex and maturity status, corresponded with the catch composition of the fishery, providing support for a meaningful exposure risk estimate. White sharks spent significantly more time in MPAs than expected by chance, likely due to increased prey abundance or less disturbance, suggesting that MPAs can benefit large, mobile marine megafauna. Conservation of white sharks in Southern Africa can be improved by implementing non-lethal solutions to beach safety, increasing the observer coverage in fisheries, and continued monitoring of movement patterns and existing and emerging threats.Publisher PDFPeer reviewe

Principles for transformative ocean governance

With a focus on oceans, we collaborated across ecological, social and legal disciplines to respond to the United Nations call for transformation in the ‘2030 Agenda for Sustainable Development’. We developed a set of 13 principles that strategically and critically connect transformative ocean research to transformative ocean governance (complementing the UN Decade for Ocean Science). We used a rigorous, iterative and transparent consensus-building approach to define the principles, which can interact in supporting, neutral or sometimes conflicting ways. We recommend that the principles could be applied as a comprehensive set and discuss how to learn from their interactions, particularly those that reveal hidden tensions. The principles can bring and keep together partnerships for innovative ocean action. This action must respond to the many calls to reform current ocean-use practices which are based on economic growth models that have perpetuated inequities and fuelled conflict and environmental decline

Key Challenges in Advancing an Ecosystem-Based Approach to Marine Spatial Planning Under Economic Growth Imperatives

In 2017, South Africa became the first African country to draft Marine Spatial Planning (MSP) legislation. The underlying legal framework supports the achievement of ecological, social and economic objectives, but a national policy to fast track the oceans economy provides a challenge for ecosystem-based approaches to MSP. During the 2018 International Marine Conservation Congress, we convened a session to present particular challenges that will likely apply to any developing country seeking to increase profits from existing, or proposed, marine activities. Here we present six multi-disciplinary research projects that support ecosystem-based approaches to MSP in South Africa, by addressing the following knowledge gaps and specific key challenges: (1) the lack of data-derived measurements of ecosystem condition (and the need to validate commonly-used proxy measures); (2) the need to develop models to better understand the potential impacts of climate change on food webs and fisheries; (3) the slow implementation of an ecosystem approach to fisheries management, and the need to implement existing legal instruments that can support such an approach; (4) the paucity of evidence supporting dynamic ocean management strategies; (5) the requirement to manage conflicting objectives in growing marine tourism industries; and (6) the need to adopt systems thinking approaches to support integrated ocean management. We provide examples of specific research projects designed to address these challenges. The ultimate goal of this research is to advance a more integrated approach to ocean management in South Africa, using tools that can be applied in countries with similar socio-political and environmental contexts

A hierarchical and modular approach to the discovery of robust associations in genome-wide association studies from pooled DNA samples

[Background] One of the challenges of the analysis of pooling-based genome wide association studies is to identify authentic associations among potentially thousands of false positive associations. [Results] We present a hierarchical and modular approach to the analysis of genome wide genotype data that incorporates quality control, linkage disequilibrium, physical distance and gene ontology to identify authentic associations among those found by statistical association tests. The method is developed for the allelic association analysis of pooled DNA samples, but it can be easily generalized to the analysis of individually genotyped samples. We evaluate the approach using data sets from diverse genome wide association studies including fetal hemoglobin levels in sickle cell anemia and a sample of centenarians and show that the approach is highly reproducible and allows for discovery at different levels of synthesis. [Conclusion] Results from the integration of Bayesian tests and other machine learning techniques with linkage disequilibrium data suggest that we do not need to use too stringent thresholds to reduce the number of false positive associations. This method yields increased power even with relatively small samples. In fact, our evaluation shows that the method can reach almost 70% sensitivity with samples of only 100 subjects.Supported by NHLBI grants R21 HL080463 (PS); R01 HL68970 (MHS); K-24, AG025727 (TP); K23 AG026754 (D.T.)

Accommodating Dynamic Oceanographic Processes and Pelagic Biodiversity in Marine Conservation Planning

Pelagic ecosystems support a significant and vital component of the ocean's productivity and biodiversity. They are also heavily exploited and, as a result, are the focus of numerous spatial planning initiatives. Over the past decade, there has been increasing enthusiasm for protected areas as a tool for pelagic conservation, however, few have been implemented. Here we demonstrate an approach to plan protected areas that address the physical and biological dynamics typical of the pelagic realm. Specifically, we provide an example of an approach to planning protected areas that integrates pelagic and benthic conservation in the southern Benguela and Agulhas Bank ecosystems off South Africa. Our aim was to represent species of importance to fisheries and species of conservation concern within protected areas. In addition to representation, we ensured that protected areas were designed to consider pelagic dynamics, characterized from time-series data on key oceanographic processes, together with data on the abundance of small pelagic fishes. We found that, to have the highest likelihood of reaching conservation targets, protected area selection should be based on time-specific data rather than data averaged across time. More generally, we argue that innovative methods are needed to conserve ephemeral and dynamic pelagic biodiversity

Conservation Planning for Action: End-User Engagement in the Development and Dual-Centric Weighting of a Spatial Decision Support System

The implementation of systematic conservation plans often involves collaboration among several organizations, so attaining consensus on the plan is an important driver of implementation success. We utilized participatory action research to explore an approach for developing consensus among organizations and facilitating implementation. A real-world challenge was addressed in the Little Karoo, South Africa by creating a spatial decision support system (SDSS) based primarily on weighted multi-criteria GIS overlays, but with an “incremental allocation algorithm” to allow efficient solution sets (i.e., systematic conservation planning). The end-users of the SDSS participated in the choice of criteria, in the selection of model parameter values, and in co-defining their group process. We co-designed a dual-centric weighting process in which the participants developed a set of weights and parameter values for attaining consensus among the organizations, and also a set for yielding the result that is best for biodiversity. The process yielded a consensus on the spatial priorities and, thus, a way forward. The estimated spatial priorities for each organization differed dramatically from each other and from the consensus priorities, indicating that a large discrepancy had been resolved. Our study indicates that the consensus-building and decision-support benefits of participatory multi-criteria overlay approaches merit closer attention in systematic conservation planning. The use of weighted overlays and an incremental allocation algorithm appear to be useful approaches for streamlining the participatory process while maintaining rigor and spatial complementarity. Finally, we uncovered theoretical psychological ramifications of the dual-centric weighting process that are promising and merit testing