Diver operated video most accurately detects the impacts of fishing within periodically harvested closures

Periodically harvested closures (PHCs) have become the most common form of spatial management in Melanesia. Despite their popularity, their effectiveness to sustain local fish stocks remains largely unknown. Here we test the ability of non-destructive sampling techniques to detect the impacts of fishing in a PHC where harvest catch data provide an impact of known magnitude. We compared the ability of three commonly used techniques (underwater visual census, UVC; diver operated stereo-video, stereo-DOV; and baited remote underwater stereo-video, stereo-BRUV) to detect the impact of a harvest on fish assemblages within a PHC in Fiji. Thetechnique stereo-DOV recorded a significant decrease in harvested individuals at both the assemblage and species level (primarily herbivorous species). The technique stereo-BRUV also recorded an impact at the assemblage level, but only for carnivorous fishes, which were less numerous in the catch. UVC did not detect an impact of the harvest at the assemblage or species level. We conclude that stereo-DOV is the most suitable technique for detecting the impactsof harvests and monitoring the effectiveness of PHCs as a fisheries management strategy, especially in areas where herbivorous fish are targeted. However, stereo-BRUV may be more appropriate where strong gradients in the abundance of carnivorous species or behavioural responses to divers are expected

Cetacean diversity, common occurrence and community importance in Fijian waters

Fiji has demonstrated a strong commitment to cetacean conservation via national, regional and international plans and agreements. To provide baseline information in support of these efforts, this paper provides an updated listing of cetacean species found in Fijian waters and identifies locations where cetaceans have been noted on a consistent basis. Information for this review was sourced from peer-reviewed publications, field reports, historical whaling records, national consultations, anecdotal and opportunistic sources, as well as a national database held by the Fiji Government’s Department of Fisheries. Reliable and recent records were confirmed for 10 cetacean species in Fijian waters. In addition, less reliable records and regional species’ information provides support for the occurrence of at least 14 additional species or groups of similar-looking species that could not be identified more specifically. Thirteen hotspot areas within the Fiji Economic Exclusive Zone were preliminarily identified as being particularly important for cetaceans, including numerous sites within the Vatu-i-Ra and Lomaiviti passages and surrounding waters. Issues with the available data include uneven coverage, inherent biases within available sources, and difficulties with species identification and verification in some cases. Nevertheless, it is hoped that this review will provide a reference point from which to move forward with cetacean management and conservation efforts in Fiji

Best‐practice forestry management delivers diminishing returns for coral reefs with increased land‐clearing

Protection of coastal ecosystems from deforestation may be the best way to protect coral reefs from sediment runoff. However, given the importance of generating economic activities for coastal livelihoods, the prohibition of development is often not feasible. In light of this, logging codes of practice have been developed to mitigate the impacts of logging on downstream ecosystems. However, no studies have assessed whether managed land‐clearing can occur in tandem with coral reef conservation goals. This study quantifies the impacts of current land use and the risk of potential logging activities on downstream coral reef condition and fisheries using a novel suite of linked land‐sea models, using Kolombangara Island in the Solomon Islands as a case study. Further, we examine the ability of erosion reduction strategies stipulated in logging codes of practice to reduce these impacts as clearing extent increases. We found that with present‐day land use, reductions in live and branching coral cover and increases in turf algae were associated with exposure to sediment runoff from catchments and log ponds. Critically, reductions in fish grazer abundance and biomass were associated with increasing sediment runoff, a functional group that accounts for ~25% of subsistence fishing. At low clearing extents, although best management practices minimize the exposure of coral reefs to increased runoff, it would still result in 32% of the reef experiencing an increase in sediment exposure. If clearing extent increased, best management practices would have no impact, with a staggering 89% of coral reef area at risk compared to logging with no management. Synthesis and applications. Assessing trade‐offs between coastal development and protection of marine resources is a challenge for decision makers globally. Although development activities requiring clearing can be important for livelihoods, our results demonstrate that new logging in intact forest risks downstream resources important for both food and livelihood security. Importantly, our approach allows for spatially explicit recommendations for where terrestrial management might best complement marine management. Finally, given the critical degradation feedback loops that increased sediment runoff can reinforce on coral reefs, minimizing sediment runoff could play an important role in helping coral reefs recover from climate‐related disturbances

Implementing a social-ecological systems framework for conservation monitoring: lessons from a multi-country coral reef program

Multi-scale social-ecological systems (SES) approaches to conservation and commons management are needed to address the complex challenges of the Anthropocene. Although SES approaches to monitoring and evaluation are advocated in global science and policy arenas, real-world applications remain scarce. Here, we describe the first operationalization and implementation of Ostrom's influential SES framework for monitoring practice across multiple countries. Designed to inform management aimed at sustaining coral reefs and the people that depend on them, we developed our SES monitoring framework through a transdisciplinary process involving academics and practitioners with expertise in social and ecological sciences. We describe the SES monitroing framework, including how it operationalizes key insights from the SES and program evaluation literatures, and demonstrate how insights from its implementation in more than 85 communities in four countries (Fiji, Indonesia, Kenya and Madagascar) are informing decision-making at multiple levels. Responding to repeated calls for guidance on applying SES approaches to monitoring and management practice, we outline the key steps of the transdisciplinary development of the framework and lessons learnt. Therefore, our work contributes to bridging the gap between SES science and commons management practice through not only providing an SES monitoring framework that can be readily applied to coral reefs and other commons, but also through demonstrating how to operationalize SES approaches for real-world monitoring and management practice

Mobile genes in the human microbiome are structured from global to individual scales

Recent work has underscored the importance of the microbiome in human health, and has largely attributed differences in phenotype to differences in the species present among individuals. However, mobile genes can confer profoundly different phenotypes on different strains of the same species. Little is known about the function and distribution of mobile genes in the human microbiome, and in particular whether the gene pool is globally homogenous or constrained by human population structure. Here, we investigate this question by comparing the mobile genes found in the microbiomes of 81 metropolitan North Americans with those of 172 agrarian Fiji islanders using a combination of single-cell genomics and metagenomics. We find large differences in mobile gene content between the Fijian and North American microbiomes, with functional variation that mirrors known dietary differences such as the excess of plant-based starch degradation genes found in Fijian individuals. Notably, we also observed differences between the mobile gene pools of neighbouring Fijian villages, even though microbiome composition across villages is similar. Finally, we observe high rates of recombination leading to individual-specific mobile elements, suggesting that the abundance of some genes may reflect environmental selection rather than dispersal limitation. Together, these data support the hypothesis that human activities and behaviours provide selective pressures that shape mobile gene pools, and that acquisition of mobile genes is important for colonizing specific human populations.National Human Genome Research Institute (U.S.) (Grant U54HG003067)Broad Institute of MIT and HarvardMassachusetts Institute of Technology. Center for Environmental Health SciencesMassachusetts Institute of Technology. Center for Microbiome Informatics and TherapeuticsFiji. Ministry of HealthColumbia Earth Institute (Institute Fellowship