https://fiji.wcs.org RSS feeds for WCS Fiji 60 https://fiji.wcs.org/Blog/articleType/ArticleView/articleId/13221/How-coral-reefs-benefit-from-healthy-watersheds.aspx#Comments 0 https://fiji.wcs.org/DesktopModules/DnnForge%20-%20NewsArticles/RssComments.aspx?TabID=3161&ModuleID=24942&ArticleID=13221 https://fiji.wcs.org:443/DesktopModules/DnnForge%20-%20NewsArticles/Tracking/Trackback.aspx?ArticleID=13221&PortalID=82&TabID=3161 https://fiji.wcs.org/Blog/articleType/ArticleView/articleId/13221/How-coral-reefs-benefit-from-healthy-watersheds.aspx As part of the Watershed Interventions for Systems Health in Fiji (WISH Fiji) project, the Wildlife Conservation Society (WCS) and our partners are trying to identify how activities on the land may be impacting downstream coral reefs. This is a bit like detective work to try to uncover convincing evidence to link human activities to reef condition. What you see on a coral reef at any given time represents an integrated history of all environmental conditions to which the reef has been exposed, both through natural and human-influenced processes. There is a high natural degree in variability of the types of corals and other benthic organisms you might find, which can be related to things like depth, reef habitat, and wave exposure. Furthermore, some coral reef organisms are better able to tolerate disturbance due to their growth forms (e.g., robust mounding corals can tolerate high energy waves much better than delicate branching corals) and genetic predisposition.                                               A river mouth adjacent to coastal reefs in Viti Levu. Credit: Stacy Jupiter Over the past few decades, there has been growing concern that rapid rates of change in how humans use the land adjacent to coral reefs is leading to unfavourable shifts in reef communities. There is evidence from numerous field studies that reefs growing adjacent to heavily altered catchments tend of have corals with higher rates of partial mortality and disease, increased algal cover, low rates of recruitment of new juvenile corals, and increased amounts of bio-erosion. Recent research from the Coral Coast in Fiji also has shown negative feedback whereby larval coral and fish preferentially avoid settling in areas with more algal growth. These issues taken together prevent reef growth and recovery following disturbance, and can ultimately lead to the breakdown of reef structure.                                         Some nearshore reefs had high abundance of juvenile coral recruits, suggesting better local                                                             conditions for reef recovery. Credit: Stacy Jupiter  What are the mechanisms that influence these impacts? Large-scale vegetation removal from watersheds and soil compaction over time can lead to higher volumes of river runoff reaching the nearshore, coupled with higher end loads of sediments and nutrients that can be compounded from poor agricultural and waste management practices. Corals, as well as other benthic reef organisms, can be quite sensitive to sudden changes in salinity, sediment and nutrient loads, as well as other chemicals that may be running of the land from pesticides or industrial activities. Elevated sediments in the coastal environment can negatively affect corals and other benthic organisms through multiple pathways. They can reduce the amount of light, which is needed by the algae (called zooxanthellae) that live in coral tissues and produce the corals’ food. Large sticky flocs called marine snow, which form in particular when sediments aggregate in high nutrient conditions, can smother coral recruits and other small benthic organisms. When these particles land on larger coral colonies, the corals may get stressed trying to slough off the particles either by ciliary action or by producing large volumes of mucus that can be washed away by currents. The increased amount of particulates and dissolved organic material has also been documented to be associated with increased microbial activity that promotes coral disease.                                              A small nudibranch makes its way across a thick carpet of sediment on coastal reefs in                                                                                   Tailevu Province. Credit: Stacy Jupiter The WCS Fiji team is at the early stages of trying to identify baseline conditions of coral reefs downstream from the Dawasamu, Waibula, Bureta and Dama river catchments in Tailevu, Lomaiviti and Bua provinces. We will use historical records and accounts of land cover change to try to identify how past activities have shaped current reef condition. And then we will work with the local communities in these locations to undertake watershed management interventions designed to reduce sediments and nutrients in their waterways and ultimately improve downstream reef condition.                                                                                 WCS Fiji dive team discussing conditions on reefs near Silana Village in                                                                                              Tailevu Province. Credit: Stacy JupiterThe WISH Fiji project also goes beyond trying to manage coral reefs. The project partners are taking an integrated approach to watershed management to improve the health of the entire linked ridge-to-reef systems, including for the people residing in the river catchments. Our collaborative research has shown that the same types of activities that degrade watersheds are also linked to the incidence and occurrence of water-related disease, such as typhoid and leptospirosis, in people. Thus, by taking a holistic approach through managing at the watershed scale, we aim to improve water safety, water quality, and overall system health. The WISH Fiji project is a partnership between the University of Sydney, Edith Cowan University, Fiji National University and Wildlife Conservation Society (WCS) in close collaboration and partnership with the Fiji Ministry of Health and Medical Services, Water Authority of Fiji, World Health Organisation (WHO), the Pacific Community (SPC), UNICEF. The project is generously supported by Bloomberg Philanthropies’ Vibrant Oceans Initiative and the Australian Government Department of Foreign Affairs and Trade. Stacy Jupiter Thu, 24 Oct 2019 02:44:00 GMT f1397696-738c-4295-afcd-943feb885714:13221 https://fiji.wcs.org/Blog/articleType/ArticleView/articleId/12478/Fisheries-outcomes-maximized-through-traditional-practice.aspx#Comments 0 https://fiji.wcs.org/DesktopModules/DnnForge%20-%20NewsArticles/RssComments.aspx?TabID=3161&ModuleID=24942&ArticleID=12478 https://fiji.wcs.org:443/DesktopModules/DnnForge%20-%20NewsArticles/Tracking/Trackback.aspx?ArticleID=12478&PortalID=82&TabID=3161 https://fiji.wcs.org/Blog/articleType/ArticleView/articleId/12478/Fisheries-outcomes-maximized-through-traditional-practice.aspx A new study published in the Journal of Applied Ecology has found a possible solution to one of the biggest conservation and livelihood challenges in the marine realm. The study’s authors—researchers from the California Polytechnic State University San Luis Obispo (Cal Poly), WCS (Wildlife Conservation Society), Swansea University, the University of Rhode Island (URI) and other groups—have found that fishing grounds with areas that are closed to fisheries but are periodically harvested are better than fishing grounds with permanent, no-take marine protected areas (MPAs). Further, the researchers found that such “pulse” harvest MPAs also perform better than traditional measures that aim to keep fisheries at maximum sustainable yield. This research could help revolutionize fisheries management and settle a long-running debate between fisheries management and conservation sectors about the role of MPAs in balancing potential for stock recovery and maintaining yields.At the crux of the matter is the current model of fishing closures. Conservationists have argued that permanently closed, no-take MPAs are an effective means of mediating overfishing and allowing stock replenishment, and many global conservation agencies are thus calling on high levels of protection in 30 percent of the world’s oceans.However, MPAs can shift fishing effort into remaining fishing grounds. More crowded fishing grounds can make it harder to find fish, thus reducing catch efficiency and driving up costs for the industry to maintain steady yields. Fisheries managers have long championed tools such as quotas and access restrictions—the second management strategy to prevent overfishing and let fish populations rebuild—to try to maintain sustainable catches. However, global declines in fish stocks have called into question whether these measures on their own are effective enough. Therein lies a tradeoff, where managers seemingly need to balance competing objectives for keeping fish in the sea and fish on the dinner plate. The researchers considered a third management strategy that is commonly implemented by small-scale fishers across the Pacific, who periodically open their fisheries closures to pulse harvests, similar to a rotational harvest model. Like permanent no-take MPAs, these periodic closures temporarily displace fishing effort and thus can promote stock recovery during the intervals while they are closed. Most importantly, however, many of the fish protected within the closure become less wary of fishing gear, giving large boosts to harvest efficiency when the closures are temporarily opened. The researchers developed innovative bioeconomic fisheries models that incorporated this documented fish behavioral response to protection. “We found that in a well-managed fishery, fishing grounds with periodic closures continuously outperformed those with non-spatial management and permanently closed MPAs for achieving the triple bottom-line objectives of simultaneously supporting high yields, stock abundance and harvest efficiency,” said Dr. Stacy Jupiter, WCS Melanesia Regional Director. The outcomes were maximized with closures for 1-2 year periods, followed by pulse harvests within a single year.  Lead author Paul Carvalho, formerly of CalPoly and presently at URI, added: “We were impressed by how well periodic closures continued to perform under different scenarios. Across a large range of closure durations, closure sizes, fish population growth rates and movement patterns, fishing grounds with periodic closures consistently gave the best combined outcomes for stock, yield and catch efficiency.” Dr. Fraser Januchowski-Hartley at Swansea University further explained: “While recreational and small-scale fishers across the world know that fish behavior can change because of fishing and protection, it normally isn’t included in management models. These results show the importance of considering changing fish behavior and its impact on catch when designing fisheries management regimes.” In fact, the only scenarios where periodic closures did not come out on top were under extreme overfishing, where the harvest efficiency benefit was too small for the periodic closure strategy to best meet the three objectives compared with permanent no-take MPAs. “Less than 25 percent of global fisheries are currently characterized by this extreme level of overfishing,” explains Prof. Crow White of CalPoly. “For these fisheries, permanent no-take MPAs may be critical for any chance at stock recovery. For the remaining three-fourths, periodic closures should be considered as an option to balance conservation and sustainable development needs for the fishing sector.” The authors of the study titled “Optimized fishing through periodically harvested closures” are: Paul G. Carvalho of the University of Rhode Island; Stacy Jupiter of WCS; Dr. Fraser Januchowski-Hartley of Swansea University; Jordan Goetze of Curtin University; Joachim Claudet of PSL Université Paris and Laboratoire d'Excellence (French Polynesia); Rebecca Weeks of James Cook University; Austin Humphries of the University of Rhode Island; and Crow White of California Polytechnic State University. This study was supported by a grant from the David and Lucile Packard Foundation to the Wildlife Conservation Society and a National Science Foundation Graduate Fellowship Research Award to the lead author. Stacy Jupiter Fri, 14 Jun 2019 00:10:00 GMT f1397696-738c-4295-afcd-943feb885714:12478