|Chair(s)/Moderator(s): Johnson, Ayana Elizabeth |
C30.2 17:45 Stable isotopes indicate trophic restructuring as a result of fishing on coral reefs. MaljkoviÄ‡, A *, Simon Fraser University; CĂ´tĂ©, IM Simon Fraser University; |
Abstract: Fisheries are believed to impact the complex trophic relationships of species in coral reef ecosystems, yet survey-based evidence establishing links between fisheries and tropho-dynamic shifts remains scarce. We used a stable isotopic approach to elucidate the effects of fisheries on the trophic ecology of reef fish over a gradient of fishing pressure in the Bahamas. Tissue samples were collected from fish species across trophic guilds and submitted for 13C and 15N isotope analysis. We calculated metrics of isotopic niche width, and shift, based on Î´13C-Î´15N bi-plots for individual species, as well as for the sampled community as a whole. Our results show that for each species sampled, isotopic niche widths collapsed by between 37% and 77% across the least fished and most heavily fished sites. For herbivorous species, niche width collapse was the result of contractions along the Î´13C axis. For predatory fish species, contractions along the Î´15N axis resulted in niche width collapse, as well as a significant reduction in the trophic level at which the largest predators fed. At the community level, an 80.5% reduction in isotopic niche width between sites at opposite ends of the fishing pressure spectrum demonstrates clearly the loss of trophic diversity resulting from fishing of reef-associated predators. Our study indicates that fisheries indirectly exert strong effects on non-target species, and highlights the importance of holistic, ecosystem-based approaches to marine resource management.
C30.3 18:00 Do seabird nutrients promote growth and enhance resilience of coral reefs? . Savage, C *, University of Otago; Rundgren, CD Independent researcher; |
Abstract: Marine conservation planning tends to focus on connectivity between seascapes to promote ecological connectivity processes, while overlooking land-to-sea connectivity. Maintaining resilience is the central plank of strategies to conserve coral reef ecosystems. Research demonstrates that seabirds are important vectors of marine nutrients to terrestrial ecosystems, but the influence of seabird-derived nutrients on marine ecosystems is less studied. Here, I examine how nutrient subsidies from seabirds can enhance resilience of coral reefs near seabird roosting sites. Using a case study from the Fiji Islands and innovative chemical tracers, I demonstrate the uptake of seabird nutrients in coral tissues. This nutrient subsidy increases coral growth and productivity of a dominant reef-building coral near seabird roosting sites. In addition, since the tight recycling of nutrients between the coral animal and symbiotic algae is responsible for the high rates of calcification in corals, seabird nutrients may enhance coral calcification. This research highlights land-to-sea connectivity processes and the importance of a holistic ecosystem-based approach that integrates marine and terrestrial systems in conservation planning.
C30.4 18:15 Among-year and within-population variation in foraging distribution of European shags over two decades: implications for marine spatial planning. Bogdanova, Maria I. *, Centre for Ecology & Hydrology; Wanless, Sarah Centre for Ecology & Hydrology; Harris, Michael P. Centre for Ecology & Hydrology; LindstrĂ¶m, Jan University of Glasgow; Butler, Adam Biomathematics & Statistics Scotland; Newell, Mark Centre for Ecology & Hydrology; Sato, Katsufumi University of Tokyo; Watanuki, Yutaka , Hokkaido University; Ito, M., National Institute of Polar Research - Japan, firstname.lastname@example.org; Parsons, M., Joint Nature Conservation Committee, Matt.Parsons@jncc.gov.uk; Daunt, F., Centre for Ecology & Hydrology, email@example.com|
Abstract: Marine spatial planning aims to deliver sustainable use of marine resources by minimizing environmental impacts of human activities and designating Marine Protected Areas. This poses a challenge when speciesâ€™ distributions show spatio-temporal heterogeneity. However, time constraints mean many studies are undertaken over few years or on a restricted subset of the population. Long-term studies can help identify the degree of uncertainty in those less comprehensive in space and time. We quantify inter-annual and sub-colony variation in the summer foraging distribution of European shags (Phalacrocorax aristotelis), using one of the longest seabird tracking datasets in the world comprising 320 individuals in 15 years from 1987 to 2010. Over this period, the shags experienced a wide range of environmental conditions, population sizes and annual breeding success. Data from one and two years captured 54% and 64% of the distribution, respectively, but it required 8 yearsâ€™ data to capture over 90%. Foraging range increased with population size when breeding success was low, suggesting interplay between extrinsic and intrinsic effects. Furthermore, sub-colony segregation in foraging areas was observed. We also present recent data (2012-2014) which suggest a downstream effect of extreme winter weather on summer foraging distribution. Our study highlights the importance of considering the proportion of the population distribution identified, ecological context and sampling design in marine spatial planning.
C30.5 18:30 Finding common ground: Regional collaboration for marine resource management in the Coral Triangle Initiative. Sarkar, S *, University of Washington; Stevenson, T. C. University of Washington; Pietri, D. M. University of Rhode Island; Pollnac, R. B. University of Washington; Christie, P. University of Washington; |
Abstract: The Coral Triangle is an area with high marine biodiversity that encompasses six countries in Asia and the Western Pacific. With the onset of threats to the regionâ€™s natural resources, a significant collaborative effort emerged in 2007 to develop a common framework for regional marine governance: the Coral Triangle Initiative on Coral Reefs, Fisheries and Food Security (CTI). Regional collaboration on marine conservation provides an opportunity for countries to jointly address shared issues. Using qualitative interviews and quantitative surveys with representatives from the six countries and their non-governmental organization partners, this study examines perspectives on collaborative management at a regional scale and documents social learning processes in the CTI. Results indicate that participants valued the CTIâ€™s regional approach to marine conservation due to its potential to address shared concerns and raise awareness about the Coral Triangle region. In addition, this study finds that regional CTI activities created opportunities for social learning, which has been demonstrated to play an important role in collaborative natural resource management. Specifically, this research documents how regional CTI activities facilitated the development of collaborative relationships and the identification of common goals for marine resource management.
C30.6 18:45 Seals and shipping noise in a dynamic sea: seasonal changes in shipping noise exposure experienced by diving seals. Chen, F *, Plymouth University; Shapiro, G Plymouth University; Bennett, K Plymouth University; Ingram, S Plymouth University; Thompson, D SMRU, University of St Andrews; Vincent, C University de la Rochelle; Russell, D SMRU, University of St Andrews; Embling, C , Plymouth University; |
Abstract: Shipping noise is a major contributor to anthropogenic noise in the sea, which is now classed as pollution in accordance with the Marine Strategy Framework Directive (MSFD). However, we know little about how it impacts marine organisms. In this study we investigate potential shipping noise experienced by grey seals (Halichoerus grypus) in the Celtic Sea by overlaying their GPS tracks and dive data, over a state-of-the-art ocean (POLCOMS) and acoustic (HARCAM) propagation model populated with real-time AIS shipping data in summer and winter. Our results show a clear influence of the seasonal thermocline (April-November) on shipping noise propagation. In summer the areas of high noise exposure were situated below the thermocline when the ship was located on the onshore side of oceanic fronts, and above the thermocline when the ship was on the offshore side of oceanic fronts. The difference in sound level between the top and bottom of the water column was as high as ~20dB. Shipping noise propagated much further (tens of kilometres) in winter than in summer. Furthermore, our study shows strong step changes of sound perceived by seals during their descent/ascent through water column. Since grey seals tend to be benthic foragers, the step-change in sound exposure may have negative impacts on their foraging behaviour. It is only through a more realistic understanding of exposure of animals to ship noise that we can set appropriate management and mitigation targets.
C30.7 19:00 The Barbuda Blue Halo Initiative: A comprehensive, science-based community-driven approach to sustainable ocean management. Johnson, AE *, Waitt Institute; |
Abstract: How can we empower communities to restore their oceans? The Waitt Instituteâ€™s answer is a new initiative, currently being piloted in Barbuda as Barbuda Blue Halo. The goal is to develop island-scale, community-driven ocean management plans that enable people to use the ocean in a way that is simultaneously sustainable, profitable, and enjoyable. The approach centers on building broad and deep consensus among stakeholders, and providing a robust toolkit that can support decision-making based on natural and social science data. The outcomes are envisioned to be a zoned ocean, improved regulation and management of fisheries, and a plan to implement these measures. This talk will focus on lessons learned from the stakeholder engagement process and the evolution from scientific recommendations to locally-appropriate policy solutions. Barbuda is a case study for examining what happens when you provide people with a robust toolkit that includes socioeconomics interviews, ecological assessment, habitat mapping, zoning analysis, legal analysis, training to build local capacity, communications, scientific monitoring, and enforcement support. How is that received, deconstructed, and leveraged for policy-decisions? What are the pitfalls and how can policies that support healthy oceans and coastal communities be built to last? Can setting more comprehensive and ambitious conservation goals lead to more progressive policies that have great benefits for society and ecosystems?
C30.8 19:15 Establishing baselines for cetaceans using passive acoustic monitoring off west Africa. Rekdahl, M *, Wildlife Conservation Society; Cerchio, S Wildlife Conservation Society; Rosenbaum, H Wildlife Conservation Society; |
Abstract: Knowledge of cetacean presence in west African waters is sparse due to the remote and logistically challenging nature of working in these waters. Exploration and Production (E&P) activities are increasing in this region; therefore, collecting baseline information on species distribution is important. Previous research is limited although a number of species listed as vulnerable or data deficient by the IUCN red list have been documented. In 2012/2013 we deployed an array of 8 Marine Autonomous Recording Units (MARUs) in a series of three deployments, off Northern Angola, targeting Mysticetes (2kHz SR, continuous) during winter/spring and Odontocetes (32kHz SR, 20% duty cycled) during summer/autumn. Preliminary results are presented on the temporal and spatial distribution of species identified from automated and manual detection methods. Humpback whales were frequently detected from August through December, with peaks during September/October. During the deployment period, sperm whales and Balaenopterid and Odontocete calls were also detected and possible species will be discussed. Species detections will be used to identify temporal hotspots for cetacean presence and any potential overlap with E&P activities. We recommend that future research efforts include visual and acoustic vessel surveys to increase the utility of passive acoustics for monitoring these populations.