2023 Guest Speaker Schedule
Coral Reef Sensing and Solutions (Geo-Ecology and New Technology)
|February 9||Sarah Davies|
|Uncovering factors governing coral symbiosis
Climate change is creating unprecedented challenges and there is an urgent need to understand the processes underlying species persistence. Predicting persistence becomes more challenging when a species’ fitness depends upon interactions between multiple partners. For corals, their fitness is tightly coupled with their symbiotic relationship with algae of the family Symbiodiniaceae, and this symbiosis is strongly influenced by increasing seawater temperatures. Research in my lab integrates eco-evolutionary experiments with genomic and environmental data to determine how corals and their symbionts interact with each other and their environments to determine symbiosis outcomes under rapid climate change. Our research spans multiple levels of biological organization from genes to populations and integrates fieldwork with molecular and population genomic approaches to answer fundamental questions in ecology and evolution.
|February 16||Simon Thorrold|
Woods Hole Oceanographic Institution
|The ecology of coral reef fishes – a brief history and recent results on larval connectivity and food web structure
Ecological studies of coral reef fishes have a relatively limited history, largely because direct observation of coral reef environments has only been logistically feasible since the advent of SCUBA in the 1940’s. Despite its novelty, the field has made significant contributions to the development of unifying concepts in ocean ecology. In this talk I will first briefly review this history before focusing on our work on recruitment and connectivity in coral reef fishes. Connectivity among fish populations on coral reefs is largely determined during a pelagic larval phase. Our lab has been investigating larval dispersal in the orange clownfish (Amphiprion percula) and vagabond butterflyfish (Chaetodon vagabundus) in Kimbe Bay, Papua New Guinea using DNA parentage analysis to provide empirical estimates of population connectivity. We are combining these estimates with results from a coupled biophysical model to assess the role played by regional circulation and larval behavior in determining connectivity patterns. Effective conservation strategies for coral reefs will require a predictive understanding of connectivity that is largely beyond our current understanding. Finally, we have quantified functional diversity in fish guilds by examining food web architecture using stable C and N isotope analysis of specific amino acids isolated from fish muscle samples from reefs in the central Pacific. Our results question the hypothesis that high diversity within reef fish guilds also implies significant functional redundancy as food webs on reefs appear highly structured. Ultimately, we hope our work will identify ecological processes that play important roles in structure, function and resilience of coral reef ecosystems and suggest ways of mitigating human impacts on reefs in the future.
|February 23||Colleen Hansel|
Woods Hole Oceanographic Institution
|Identifying chemical controls and signatures of coral reef health
The physiology and health of corals are intimately tied to the concentration and flux of chemicals within their tissues and in the surrounding waters. Reactive oxygen species (ROS) are a group of oxygen intermediates that are tightly regulated by organisms as they can be both essential and detrimental. Our research has highlighted the potential role for the ROS hydrogen peroxide to serve as an indicator of stress within corals and other reef organisms, such as macroalgae. While identifying early-stage diagnostics of organismal health is critical for assessing and predicting reef health, chemicals may also provide a means of preserving and restoring reefs. For instance, metal micronutrients are essential for a suite of metalloenzymes and metabolic processes involved in growth and immunity in coral reef organisms. Yet, corals often exist in oligotrophic regions typified by low macro- and micro-nutrients. We are therefore researching the potential to increase coral growth and resilience via metal micro-nutrient supplementation. We are creating recruitment and growth substrates specifically formulated with mineral mixtures that will release nutrients at optimal rates. We hope that by designing novel monitoring tools and nature-inclusive substrates we can contribute to the protection and restoration of coral reef ecosystems.
|March 2||Pete Edmunds|
California State Northridge
|Four decades of change on coral reefs in the Caribbean and South Pacific: A long series of unfortunate events
The contemporary coral reef crisis presents modern coral reefs in a homogeneous state of greatly reduced coral cover, enhanced macroalgal abundance, and depleted fish populations. Within the context of the Anthropocene Epoch, this state does not bode well for the future of reefs in warmer seas at lower pH. Explanations of how we got to this point tend to emphasize the role of single disturbances (e.g., bleaching), which suggests that the cause(s) of the crisis, and its possible solutions, might require mitigation of one, or a few, stressors. Using up to four decades of ecological time series data from the shallow reefs of St. John, US Virgin Islands, and Moorea, French Polynesia, I make the case that the present state of coral reefs is: (a) more varied than often is described, and (b) a product of a long series of “unfortunate event” that have interactive and cascading effects that will be highly challenging to reverse. Yet, despite the gloomy state of modern reefs, a deeper understanding of coral ecology, and emerging functional analyses of scleractinian corals, reveals ways through which at least some corals might persist in a rapidly changing world.
|March 9||Howard Lasker|
University of Buffalo
|A new normal for Caribbean Reefs?
Coral reefs throughout the tropics have experienced large declines in the abundance of scleractinian corals. This is especially true of Caribbean reefs, where scleractinians are no longer the dominant member of the benthos. Macroalgae have increased in abundance throughout the Caribbean, but on reefs where they have been monitored arborescent octocorals, gorgonians, have persisted and are numerically and functionally dominant on some reefs. The persistence of octocorals on Caribbean reefs can in large part be related to their relative resistance to stresses such as coral bleaching and diseases, and populations have been adversely affected to the resilience driven by recruitment, rapid growth and potentially by feedback driven by the hydrodynamics of the animal forest they create. Octocorals are one of several taxa that have been overlooked for decades in analyses of coral reef community dynamics. A clearer understanding of their ecology and dynamics will be critical to understanding the future of Caribbean reefs.
|March 16||Kristen Marhaver|
CARMABI Foundation, Curacao
|Advancing coral conservation and restoration using materials engineering, cryopreservation, and good old natural history
Decades of natural history observation and fundamental research on coral spawning have made coral in vitro fertilization and larval propagation possible, while paving the way for the rapidly-accelerating field of coral reef restoration. In this talk, we’ll tour the coral life cycle, from spawning and embryogenesis to larval settlement and metamorphosis, using rare footage captured over the past 15 years in Curacao. With this natural history work as the foundation, we’ll discuss two areas where engineering and innovation are accelerating reef restoration. First, materials engineering allows restoration scientists to search parameter space for better-performing coral settlement substrates. Our team and collaborators have induced coral settlement in the absence of biological cues, using a lime-mortar base with chemical additives known to support calcification. Second, cryopreservation of coral sperm allows the long-term preservation, long-distance transport, and fortification of coral genetic diversity. Our team completed the first successful demonstration of coral assisted gene flow in the Caribbean using endangered Elkhorn Coral. Interdisciplinary work combining natural history and engineering will continue to accelerate the conservation of coral genetic diversity worldwide.
|Assessing the Role of Coral Reefs in Coastal Hazard Risk Reduction from the Scale of Kilometers to Centimeters
Coral reefs are effective natural barriers that protect adjacent coastal communities from hazards such as erosion and storm-induced flooding. However, the degradation of coral reefs compromises their efficacy to protect against these hazards, making degraded reefs a target for restoration. At present, there is little guidance on how and where to restore coral reefs for coastal hazard risk reduction. Here I present modeling we have done at a series of scales to provide such guidance. At regional scales (order of kilometers), we are working to determine where potential coral reef restoration could decrease the hazard faced by reef-fronted coastal communities. At reef scales (order of meters) scales, we are assessing the optimal locations of coral restorations on a reef to reduce coastal flooding for various types of reef topographies. At coral scales (order of centimeters), we are evaluating the turbulent kinetic energy dissipation provided by the hydrodynamic roughness of individual and groups of corals to best design the coral restorations for maximum performance at minimum cost. Together, the results from these efforts help identify how and where coral reef restorations could potentially help reduce the risk to, and increase the resiliency of, generally underserved, at-risk, and predominantly native coastal communities. The optimization and quantification of coral reef restoration efforts to reduce coastal flooding is also opening hazard risk reduction funding for coastal conservation purposes.
|March 30||BREAK, NO SPEAKER|
|April 6||David Vaughan|
Plant a Million Corals, Florida Keys, FL
|Active Coral Reef Restoration of the Massive Corals in our Lifetime
Dr. Vaughan will summarize 20 years of work on coral culture and restoration, and highlight the projects of developing a coral aquaculture research program and large scale coral production hatcher, training programs (“Coral College”) in the Florida Keys and other locations. Developing land based nursery production innovations, and micro-fragmentation, a mistake from breaking the first “test-tube” baby corals with the water supply systems. Starting with Marine ornamental research project with Nemo production (clownfish), culminating in the development of ORA and the tank culture of reef species for the aquarium trade and finalizing my evolution into raising corals for ocean reef restoration.
|April 20||Tim Shank|
Woods Hole Oceanographic Institution
|Cold-Water Coral Ecosystem Diversity: Understanding Interactions with Habitat, Environmental Factors, and the Fidelity of Corals and Faunal Symbionts for Conservation and Management
Understanding the patterns of biodiversity, biogeography, evolution, and ecological interactions in deep-water coral ecosystems has reached a critical level with anthropogenic activities, including fisheries, mining, acidification, ocean warming, oil and gas exploration, and plastic pollution that threaten deep-sea coral ecosystems. Corals provide complex, rich, and varied habitats that promote ecological interactions and biodiversity. More than 3,300 deep coral species have been described from deep-water canyons, seamounts, gulfs, and mid-ocean ridges. Research over the last two decades has largely focused on the identification, composition and distribution of deep-water coral species, while the diversity of animals living on them has received much less attention, despite the desire to understand coral ecosystem diversity for ecological research and conservation. These corals not only host a diverse array of taxa (>3,400 species of crabs, polychaetes, and ophiuroids), but these epifaunal partnerships are often a highly specific to the coral host, suggesting important ecological and evolutionary interactions the form and maintain biodiversity. I will introduce deep-water corals, their specific relationships with epifaunal symbionts, their distribution and diversity with depth and environmental factors, and discuss the growing threats to these vulnerable marine ecosystems. Lastly, I will discuss future work that will inform conservation, management, and restoration efforts seeking to maintain diversity in cold-water coral ecosystems, including the recent creation of Atlantic and Pacific National Marine Monuments and Marine Protected Areas that are currently under active national debate.
|April 27 - CARRIAGE HOUSE||Aaron Hartmann|
|ARMS to reefs: A new approach for building coral reef habitat, increasing fisheries yields, and improving human health in Madagascar
Coral reefs are one of the most valuable ecosystems on the planet and are disappearing at an alarming rate. The loss of coral reefs threatens human lives because reefs provide food, income, and shoreline protection. Global efforts are underway to restore reefs, with mixed success. We are taking a new approach to this problem by seeding reef communities onto artificial structures, rather than just framework-building corals. We are working with local fishing communities in Southwest Madagascar to build six 1-ha artificial reefs, then seeding half with reef communities growing on limestone pyramids called ARMS. Supported by the Belmont Forum and NSF, our international team of ecologists, fisheries scientists, and human nutritionists is quantifying the full-system response of jumpstarting reef growth with this simple technology. Our before-after-control-impact or BACI design will allow us to quantify our success in achieving our primary goal: to rebuild coral reef ecosystems and increase fish catch to reduce malnutrition in one of the most impoverished countries in the world.
|May 4||Ved Chirayath |
University of Miami
|Revealing the ocean deep: Next-generation sensing technologies for marine & planetary science
We have mapped more of the surface of the Moon and Mars than our own ocean floor—but that is changing. Professor Ved Chirayath will present three sensing technologies he invented during his time at NASA. These technologies will help us better understand Earth’s marine environments while furthering the search for life on other planets.
FluidCam is an instrument that can be used from satellites and aerial drones to map shallow marine environments, such as coral reefs, at unprecedented resolution in 3D. MiDAR is a multispectral instrument that can be used to sense living creatures and nonliving structures in light-limited environments like the ocean floor. Finally, NeMO-Net is a machine-learning video game that teaches citizen scientists to classify coral reefs at high accuracy using real data from FluidCam & MiDAR. Together, these technologies present promising innovations that address ongoing challenges in mapping oceans on Earth and other planets.
|May 11||Kristen Davis |
University of California Irvine
|Characterizing environmental gradients in reef ecosystems: physical processes driving high-frequency and fine-scale spatial variability
In coral ecosystems, variation in environmental conditions supports a mosaic of coral communities in which spatial insurance effects could enhance community stability. One of the major challenges to understanding community structure on reefs and the resilience of coral communities to climate change is in quantifying physical and biological patterns at appropriate spatiotemporal scales. Here we examine physical processes shaping environmental gradients on Dongsha Atoll, a coral reef and Taiwanese National Park in the South China Sea during an observational campaign in summer 2019. Physical processes considered include atmosphere-ocean heat exchange, surface and internal waves, tides, and wind. Among the observations presented, measurements from a distributed temperature sensing (DTS) system offer a spatially-continuous view of the near-bed temperature field. The DTS measurements enable detailed resolution of thermal microclimates on the reef and internal wave dynamics. At Dongsha Atoll internal waves shoaling on the shallow atoll regularly transport cold, nutrient-rich water shoreward, altering near-surface water properties on the fore reef and shallow reef flat. Further, the water transported over the reef flat modifies the residence time and biogeochemical properties of the atoll lagoon.