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An interview with the WCS Marine Scientist, Yashika Nand
Interview by Dwain Qalovaki
Q. What got you interested in coral disease?
Nand: In 2012, I conducted a “Training of Trainers” workshop for community leaders and conservation partners on “Reef Resilience”. Coral disease was a minor component of that training as an emerging threat to reef ecosystems. The interest and concerns raised by community representatives on coral disease got me interested in the topic. After doing a literature search on global impacts of coral disease, and reading about the challenges in identifying the causes and environmental dynamics associated with pathogens, I was determined to join the group of coral disease researchers.
With limited information in Fiji on coral disease and no known expertise, I was challenged but was glad WCS Fiji Director Dr. Stacy Jupiter introduced me to Professor John Bythell, who is keen scientist specializing in coral disease.
Equipped with a supervisor like Professor Bythell and advisor like Dr. Jupiter, I couldn’t stop myself from starting a Masters program at the University of the South Pacific (USP). Later Dr. Joeli Veitayaki (USP) and Dr. Cara Miller from the Whales and Dolphins Conservation Society joined my journey of discovery to understand coral diseases in Fiji by agreeing to be my co-supervisors.
Q. What is the focus of your Masters research in relation to coral disease?
Nand: I am looking at the general distribution and prevalence of coral disease in Fiji. My research is likely to be the first baseline study on coral disease for the country but I will also be focusing on the progression rates of one specific coral disease referred to as the “White Syndrome” in the Western Pacific Region.
A similar condition referred to as “White Plague I & II” in the Caribbean caused more than 80% coral mortality; hence it’s considered a serious threat to reef ecosystems. My research will also assess temporal changes over hot (November – April) and cold (May-October) months in Fiji over a year.
Q. Has anything unexpected come up during your research so far?
Nand: Currently, a lot of anomalies observed in corals with very high prevalence in some areas and patchy distribution of disease in other areas. There are a few corals that are more vulnerable to certain types of disease. I expected more coral disease in areas closer to the coastline but to my surprise in some cases I found more disease on outer reefs further from the land.
Q. What are the major ecosystem threats that you are beginning to notice at your research site?
Nand: Influx of nutrients and freshwater especially for Leleuvia Island that is causing more stress to corals in the area. Moreover, the sudden change in water temperature makes it difficult for corals to adapt. I have seen evidence for this in the months of December 2013 – February 2014, where warm waters caused coral bleaching in many places around Fiji including the Yasawa Islands.
Under these conditions, corals immune system weaken and pathogens such as bacteria, ciliates, and fungi present in the water column take advantage and invade corals causing different types of disease. Some are extremely detrimental to the health of corals.
Other threats include predation which causes coral mortality. Organisms like Crown-of-Thorns starfish (COTS), Drupella snails, and some marine worms have the potential to kill a whole colony. Cyclone damage can also affect reef systems, fragmenting and killing fast growing corals.
Q. Going forward, how can we slow, stop or reverse these effects?
Nand: I am still analysing videos that I collected from September 2013 to February 2014 so some of these questions will be answered later on in my Masters. Researchers in the Caribbean, Australia and Hawaii are also looking for answers to these same questions.
Q. Do you have any advice for Fijian or Pacific Island scientists who want to get more involved in coral disease research?
Nand: Try to collect data on coral disease. Taking photos/videos of reefs that show signs of disease can help us understand where and how disease spreads within reef systems. Pacific Islands are so scattered that it is really difficult to collect data so most predictions on outbreaks of coral disease or other stressors on reefs are made based on data from easily accessible places – this does not give a good representation of reef health in the region.
I think coral disease is a challenging yet important and interesting area of research that may grow in prevalence if we do not better manage our reefs, or with the growing stressors associated with climate change.
In 2011, I participated in a workshop during the International Marine Conservation Congress in Victoria, Canada, where experts came together to discuss which were the most critical factors that affect the ability of coral reefs to resist and recover from climate disturbance. After much deliberation, our expert consensus produced a list with 11 top resilience indicators, based on their perceived importance, evidence base in the literature, and feasibility for managers to measure. The top indicators included:
– Presence of resistant coral species
– Historical temperature variability
– Nutrient pollution;
– Coral diversity;
– Herbivore biomass;
– Physical human impacts;
– Coral disease;
– Coral recruitment; and
– Fishing pressure
We published a paper describing the selection of these indicators and how they might be used to prioritize sites for reef management in a changing climate.
However, during this process, I got to thinking. Site based measures of resilience indicators are nice, but they only allow us to say that one survey point is potentially better than any other survey point and leaves you with no information about all of the unsurveyed reef.
Wouldn’t it be even better, then, if we could combine the field data with satellite imagery to assess what are the main factors influencing the resilience indicators that we can derive from space? Then we could use those relationships to predictively map the resilience indicators over a broader spatial scale, such as across an entire fisheries management area (qoliqoli). This process would yield maps with relative values for every portion of the qoliqoli to enable us to make better decisions about how to plan marine protected areas (MPAs) and MPA networks.
We previously took this approach to predictively map characteristics of reef fish assemblages across the Kubulau qoliqoli in Vanua Levu, Fiji, and published the results in a paper in Remote Sensing. I went back to my co-authors from Simon Fraser University and the University of Queensland and asked, “Do you think we can take this same approach for mapping indicators of reef resilience?”
Our findings have just been published in a more recent issue of Remote Sensing, accessible here. We specifically focused on mapping resilience indicators for which data products were not already available. These included:
– Stress-tolerant coral taxa, as a measure of resistance to coral bleaching;
– Coral diversity, as a measure of resistance to bleaching and potentially past recovery potential;
– Herbivorous fish biomass, as a measure of recovery potential due to the ability of herbivorous fishes to remove macroalgae from the reef, thus preventing harmful coral-algae interactions and allowing space for new corals to settle;
– Herbivorous fish functional group richness, as a measure of recovery potential as fish remove algae in different ways (e.g. excavating, scraping, browsing) and it is necessary to have the full complement of types of herbivores to effectively remove most of the macroalgae;
– Juvenile corals, as a measure of recovery potential from recent coral recruitment and survival; and
– Cover of live coral and crustose coralline algae, as a measure of recovery potential both as a indicator of current coral-algal dynamics when coupled with the amount of macroalage, as well as a proxy for the amount of substrate available for coral settlement and source of new recruits.
We specifically used high resolution satellite data (<4 m pixels) to enable production of maps of resilience indicators at a scale meaningful for customary management systems in Fiji and the rest of the Western Pacific. We did not try to predictively map indicators which other people have successfully mapped (e.g. historical temperature variability, nutrients, sedimentation, physical impacts and macroalgae), but noted that our predictive maps could be combined with these data products within a spatial planning framework.
How well did we do? We were able to reasonably map relative differences in potential susceptibility to coral bleaching based on the composition of coral communities observed in the field. We were able to do this because some corals are more tolerant to environmental stress than others and they tend to be found in different environments and micro-habitats.
We also did a good job predicting distributions in the number of functional groups of herbivorous fish. This indicator likely also has strong environmental determinants as large excavators, such as bumphead parrotfish, steephead parrotfish and bicolor parrotfish, tend to be associated with forereef slopes and reef crests. We noted, though, that the total amount of “reef cleaning” performed by each group of herbivorous fish will be influenced by how many fish are present and their size. In addition, not all herbivorous fishes are created equal. A new, separate study from Fiji found that only 4 species of fish were responsible for eating 97% of the algae set out in a feeding experiment.
We did not do such a good job in predicting distributions of juvenile corals, but this was expected given that there are many factors that influence where corals may settle and how many survive. We also did not do very well in predicting coral diversity patterns. This was somewhat surprising given how much is already known about relationships between coral diversity and depth, exposure to waves and reef habitat. However, our results were likely influenced by errors in georeferencing and incomplete sampling across all of the habitat types in Kubulau qoliqoli. These issues could easily be improved upon in future studies.
What does this mean for reef managers? In the context of MPA planning, managers now have the potential to set targets for reef resilience indicators, in addition to habitat and feature representation, when designing MPA networks within decision support software (e.g. Marxan). This represents a considerable improvement over the current practice of designing or adapting MPAs based on site-based resilience score collected from relatively few sites across the planning region.
After only 2 weeks respite from our periodic harvest surveys in Kubulau, the Fiji marine team has again packed up our kit and by planes, boats and automobiles made our way to the remote regions of western Bua Province. Given our success assisting the districts of Kubulau and Wainunu to develop and implement their ecosystem-based management plans, the Bua Provincial Office requested for WCS to replicate the model with the remaining districts in the province. So we’re here to use our well-honed survey methodology to gain baseline data that will allow us to develop recommendations for marine protected area (MPA) network design. We’ll present the recommendations back to the communities during the first half of 2013 to ideally help local communities achieve their fisheries and livelihoods goals.
Our first destination was Navunievu village in Bua District. Natalie and I, as early arrivals, spent the afternoon drinking kava waiting for the others to arrive. The ladies on our team were assigned sleeping quarters on the floor in the village hall, which meant we were constantly the centre of attention for eager children curious to check out photo slideshows and chatty ladies wanting to constantly peer at what we were doing. This made working, changing and sleeping challenging to say the least, and we jealously coveted the boys’ beds and privacy in their separate houses.
Our second challenge was the weather. “E tau na uca veisiga i ke? (Does it rain everyday here?)” I asked just about anyone who would listen. They generally would just smile. Perhaps my Fijian accent is terrible or it is just a silly question—because, yes, of course it rains every day in Navunievu. This put a slight damper on our fieldwork when lunches of tinned tuna turned to tuna soup, and visibility at certain sites, particularly near the mangroves, turned to pea soup. However, despite the poor vis, we were pleased to note that the Bua District tabu (MPA), established nearly a year ago, was working well, with plenty of large food fish.
As if on cue, it began to pour as we departed Navunievu at the end of our first week, but the skies soon cleared and a rainbow halo rimmed the peaks of Yadua Island, our next destination. The smaller island adjacent to Yadua, Yadua Taba, is famous in Fiji as the home to Fiji’s endemic crested iguanas. The National Trust of Fiji has worked with the communities to establish a wildlife sanctuary on Yadua Taba for the approximately 20,000 iguanas living in one of the few remaining intact dry forests in Fiji. It is believed that the first iguanas rafted here across the Pacific from South America. Given that Yadua Taba is home to 90-95% of the crested iguanas in Fiji, the species is highly vulnerable to threats from invasive alien species, such as rats, as well as habitat damage and climate change. Twenty thousand iguanas is quite a lot for a 70 ha island, so it didn’t take us long to spot them hanging out in the trees, munching on hibiscus leaves. Some were willing photo subjects—others were more feisty. I had two Jurassic Park moments when the lens of my camera was attacked by some not-so-amused reptiles.
The community of Yadua village has also established a permanent, no-take tabu area on the reefs and other coastal habitats around Yadua Taba. However, our first impressions are that it may be subject to heavy poaching, given how quickly the fish flee from approaching divers. Unfortunately, these days in Fiji, given the weak legislation to support community-managed MPAs and lack of capacity for enforcement, once a tabu becomes well-known, it is like having a giant flashing beacon saying “FISH HERE!” It is no help that the latest draft of the Inshore Fisheries Decree has been put on hold indefinitely. I’m trying to stay positive that we can still empower the communities and provincial governments to work within the existing system and restrict fishing licenses.
The sea cucumber (or beche-de-mer) fishery requires the most urgent regulation. In general, Fijians do not eat most beche-de-mer. They are sold to middlemen for export to Hong Kong and on to the Chinese market. As single white teat may fetch over FJ$100, the perception is that they are just easy cash for the taking sitting on the reef. However, there are three big reasons why people should pay attention to the serial exploitation of species and regulate the fishery. First, sea cucumbers are the sweepers of the sea. They play important roles in nutrient cycling, which keeps algal blooms at bay. Secondly, with exemptions from the Fiji Department of Fisheries to collect beche-de-mer on SCUBA but improper training, divers are literally killing themselves by pushing depth limits to find valuable species as they become more and more rare. Lastly, the middlemen are taking most of the profits. If the communities were able to have more control, they could keep more of the benefits for themselves and control extraction rates so that they might always be able to “cash out” a haul in times of real need.
As it stands now in Yadua, there is a Korean middleman who has been operating from the next bay for over 20 years with the permission of the high chief of the area, who does not live on the island. The community is unhappy, and the chief of Yadua has encouraged the young men to collect as many beche-de-mer as they can, thus forming a race to catch the last individuals. Currently the wealth is evident in the community, with generators, compressors, televisions and other appliances that we do not usually see in rural villages. However, I can only imagine the impending social issues that might be faced once the cash flow dries up when beche-de-mer populations collapse.
Another critical challenge facing Yadua is potential impacts of extreme weather from climate change. Water security is a serious issue on the island. Recently, a borehole was located to supply the village with water for drinking and cleaning, but it requires a diesel-powered generator to operate the pump. Just the other day, the community ran out of fuel for the generator, and the thought was to catch some of the wild goats on the island to sell for purchase of more fuel. They did indeed catch the goats, but with heavy winds, they were unable to take them across to Vanua Levu and no fuel could be bought. Meanwhile, the water levels continued to drop in the barrels and buckets.
For our third week in the field, we moved over to Yaqaga Island in Lekutu District, also home to iguanas and, much to our pleasure, running water and flush toilets! The men of Yaqaga are also busy collecting beche-de-mer, which they sell to another middleman based in Galoa village. They have already seen declines in numbers on the surrounding reefs and are fishing less valuable species, like snakefish. Meanwhile, untrained divers are putting their lives at risk plunging to depths of over 80 m to find the remaining individuals. One diver, who recently suffered the bends, is now relegated to growing watermelons on the far side of the island. Unlike in Yadua, the people of Yaqaga and Galoa asked questions about what might be the impact of wholesale removal of beche-de-mer and what could be alternative sources of income for their children.
These communities also have another source of concern. Several years ago, the Fiji Government granted permission to a Chinese mining company to extract bauxite, used to make aluminium cans. The Chinese company was smart— in order to get their foot in the door in Fiji, they chose a small (<30 ha) site in pine plantation of limited conservation value and developed plans to export the ore back to China for the more ‘dirty’ processing steps. However, in the future, ore from other, larger claims may be processed in Fiji. In the meantime, communities say that they are already feeling the impact of increased runoff of sediments from the Nawailevu mine and jetty. They say it has become harder to find Anadara clams (‘kaikoso’) and the waters have become increasingly silty.
Clearly there is much work to be done in this region and we are eager to help the communities both sensibly engage with the natural resource extraction industries, as well as develop management plans to balance their own needs for income generation with sustainable livelihoods. Stay tuned.
Fiji delegates shared conservation success stories and ongoing efforts at the 12th International Coral Reef Symposium (ICRS) in Cairns, Australia (9-13 July 2012). Fiji was represented by partner organizations from the Fiji Locally Managed Marine Area (FLMMA) network, including WCS Fiji (Stacy, Margy, Akuila and I made up our team), the Institute of Applied Sciences (IAS) at the University of the South Pacific, and SeaWeb.
Although not officially part of the coral triangle hotspot, Fiji was shown to be a marine biodiversity hotspot in Stacy’s presentation. Margy captured a lot of attention by linking traditional knowledge to protecting spawning aggregation sites in Fiji. Akuila shared his story on the importance of adaptive management. I became a celebrity, posing with my poster on “Consideration of disturbance history for resilient MPA network design”. Ron Vave (IAS), charmed the audience with his findings on the effectiveness of locally managed marine areas in Fiji, while Saki Fong (IAS) shed more light on the socioeconomic implications of establishing these marine protected areas. Semesi Meo gave the audience a show on ecological effectiveness of community-based management in Fiji. Alifereti Tawake (a former IAS staff member, now a PhD student at James Cook University) talked about social and cultural attributes of effective adaptive management systems.
Our shared experiences of conservation on the ground were enough to let the world know about Fiji. The reports from international students who have worked in Fiji got other people interested in working in these beautiful islands in the future – this really gave us a boost to hear their enthusiasm.
ICRS was a great chance for us to network with a number of leading conservation managers and scientists from all over the world. At the same time we were digesting as much information as possible from the diverse efforts being undertaken internationally to ensure coral reefs thrive in the future.
Here are the 3 parts of Fiji One’s ‘Close Up’ show, including an interview with WCS Fiji Director Dr Stacy Jupiter. The footage was shot earlier this month in the remote Daria village, Wainunu, when the communities launched their network of 7 terrestrial, freshwater and marine protected areas. Luckily the sun shone for the filming; a rare treat in the famously rainy Wainunu.
This new protected area network covers 52 km2, with 6km2 in 4 periodically harvested fisheries closures (tabu areas) and the remaining 46km2 in 3 upland protected areas; equivalent to 5% of the Wainunu traditional fisheries management area and 17% of the district lands. The marine protected areas focus on resilient reefs which have the best chance of ensuring future food security in the face of climate change.