Linda Eggertsen

Seafood plays a vital yet underexplored role in addressing nutritional deficiencies in tropical countries. Despite Brazil’s vast coastline and marine biodiversity, seafood contribution to human nutrition remains insufficiently quantified. Here we present a nationwide assessment of seafood’s nutritional role in Brazil by integrating household-level dietary data (n > 30,000), nutrient composition of protein sources and fisheries statistics. We find that average seafood intake is below recommended levels, at 5.3 kg per capita per year, while nutritional deficiencies, including vitamin A and calcium deficiencies, remain widespread. Projections show that increasing seafood consumption from 6% to 25% of total protein intake could substantially reduce these deficiencies. However, seafood demand exceeds fisheries supply in several states, underscoring the limited potential to increase fishery catches and that targeting seafood consumption based on nutritional value could maximize health benefits. Our findings emphasize the role of marine resources in human nutrition and underscore the need for improved fisheries governance and sustainable seafood policies in Brazil.

Ocean warming is increasing the frequency, extent, and severity of tropical-coral bleaching and mortality. During 2014–2017, marine heatwaves caused the Third Global Coral Bleaching Event. We analyze data from 15,066 reef surveys globally during 2014–2017. Across all surveyed reefs, 80% and 35% experienced moderate or greater (affecting >10% of corals) bleaching and mortality, respectively. We assess the global extent of coral bleaching and mortality by applying bleaching response curves calibrated from surveyed reefs to predict bleaching globally, based on comprehensive remote-sensing of heat stress. These models predict that 51% and 15% of the world’s coral reefs suffered moderate or greater bleaching and mortality, respectively, during one or multiple years, surpassing damage from any prior global coral bleaching event. Our findings demonstrate that the impacts of ocean warming on coral reefs are accelerating, with the near certainty that ongoing warming will cause large-scale, possibly irreversible, degradation of these essential ecosystems. With heat stress levels during this event surpassing those observed previously, the National Oceanic and Atmospheric Administration developed more extreme Bleaching Alert levels that are now being used during the ongoing Fourth Global Coral Bleaching Event.

Parrotfish are considered a key functional group on reefs, yet little information exists on home ranges of this group. We estimated short-term home ranges of two species of parrotfish (Sparisoma axillare and S. frondosum) on subtropical rocky reefs in Arraial do Cabo, Brazil, using active acoustic telemetry. We tagged 39 S. axillare and 25 S. frondosum and monitored them for 6.4 ± 0.35 days. Both species showed high residency during monitoring and relatively small home ranges of 30,600 m2± 3,000 SE for S. axillare and 31,200 m2± 4,000 for S. frondosum (Minimum Convex Polygon). Home range size increased with size of fish and was dependent on life phase for S. axillare, but not for S. frondosum. The relatively small home range sizes compared to other species and the same species in other locations may be related to high productivity and resource availability locally. The high residency and small home ranges observed here indicate that, at least under the short-term and site-specific conditions of Arraial do Cabo, small Marine Protected Areas could offer conservation benefits for S. axillare and S. frondosum, although broader and longer-term studies are needed to confirm this across their range.

Seafood is vital for tropical coastal communities, but demand and supply in Brazil remain poorly documented despite its extensive coastline and marine resources. We analyzed food consumption from over 40,000 interviews and nutritional content for six nutrients (Ca, Fe, Se, Vitamin-A, Omega-3, and Zn), comparing seafood with land-based protein sources. Our simulations show that increasing seafood consumption by 50% could meet FAO's nutritional recommendations, while a 50% increase could align all nutrient intakes. The average per capita seafood consumption is 5.3 kg/year, with lower-income populations in the North and wealthier groups in the South consuming more. Fish and shellfish are richer in most nutrients, except Zn. However, seafood production often falls short of consumption, highlighting a supply-demand mismatch. Sustainable fisheries management and expanded monitoring are essential to improving Brazil's nutrition and food security.

Understanding the diurnal and nocturnal activity of organisms is a key topic in behavioral ecology, with implications for population structure and management strategies. In reef systems, parrotfishes play crucial roles as nominal herbivores, but overfishing has led to population collapses with detrimental effects on reef functions. Parrotfish are good models to study diel rhythms, as they are often easily observed while sleeping at night. We assessed the distribution, sleeping substrate selectivity and sleeping areas of parrotfishes during the night in a subtropical rocky reef of the Southwestern Atlantic. We performed replicated visual censuses (50 × 2 m) at different depths to estimate parrotfish abundance, while quantifying the structural complexity of sleeping sites. Among the seven recorded parrotfish species, we focused on the four most abundant to determine their sleeping habitat selectivity. Active telemetry was used for the two most abundant species to define their sleeping site areas and sleeping hotspots. All four species exhibited a preference for sediment as a sleeping substrate, while avoiding zoanthids. Species distribution was influenced by depth, with Scarus zelindae predominantly sleeping in high-complexity substrate at intermediate depths and Sparisoma tuiupiranga sleeping in the rock–sand interface at deeper depths. Tagged Sparisoma axillare and Sparisoma frondosum exhibited similar sleeping areas in terms of size and geographical locations; showing high site fidelity, they returned to the same sleeping sites over consecutive nights. These results represent the first assessment of parrotfish distribution and habitat use at night in the Atlantic. This information is crucial for guiding management actions, particularly in the planning of no-take zones for fishing control and population recovery.

The global decline of coral reefs has led to calls for strategies that reconcile biodiversity conservation and fisheries benefits. Still, considerable gaps in our understanding of the spatial ecology of ecosystem services remain. We combined spatial information on larval dispersal networks and estimates of human pressure to test the importance of connectivity for ecosystem service provision. We found that reefs receiving larvae from highly connected dispersal corridors were associated with high fish species richness. Generally, larval “sinks” contained twice as much fish biomass as “sources” and exhibited greater resilience to human pressure when protected. Despite their potential to support biodiversity persistence and sustainable fisheries, up to 70% of important dispersal corridors, sinks, and source reefs remain unprotected, emphasizing the need for increased protection of networks of well-connected reefs.

Spatial configuration of habitat types in multihabitat seascapes influence ecological function through links of biotic and abiotic processes. These connections, for example export of organic matter or fishes as mobile links, define ecosystem functionality across broader spatial scales. Herbivory is an important ecological process linked to ecosystem resilience, but it is not clear how herbivory relates to seascape configuration. We studied how herbivory and bioerosion by 3 species of parrotfish were distributed in a multi-habitat tropical seascape in the Western Indian Ocean (WIO). We surveyed the abundance of three species with different life histories—Leptoscarus vaigiensis (seagrass species), Scarus ghobban (juvenile-seagrass/adults-reefs) and Scarus rubroviolaceus (reef species) —in seagrass meadows and on reefs and recorded their selectivity of feeding substrate in the two habitats. Herbivory rates for L. vaigiensis and S. ghobban and bioerosion for S. rubroviolaceus were then modelled using bite rates for different size classes and abundance and biomass data along seascape gradients (distance to alternative habitat types such as land, mangrove and seagrass). Bioerosion by S. rubroviolaceus was greatest on reefs far from seagrass meadows, while herbivory rates by S. ghobban on reefs displayed the opposite pattern. Herbivory in seagrass meadows was greatest in meadows close to shore, where L. vaigiensis targeted seagrass leaves and S. ghobban the epiphytes growing on them. Our study shows that ecological functions performed by fish are not equally distributed in the seascape and are influenced by fish life history and the spatial configuration of habitats in the seascape. This has implications for the resilience of the system, in terms of spatial heterogeneity of herbivory and bioerosion and should be considered in marine spatial planning and fisheries management.

Structural complexity spanning fine to broad spatial scales can influence the distribution and activity of key organisms within marine ecosystems. However, the relative importance of hard (e.g., corals) and/or soft (e.g., macroalgae) structural complexity for marine organisms is often unclear. This study shows how both broad-scale (seascape configuration of coral structure) and fine-scale habitat complexity (structure height, number of holes, and presence of macroalgae) can influence the abundance and spatial ecology of reef fish. Underwater visual census of fish, surveys of habitats, remote underwater videos, and behavioral observations by following individual fish were used to quantify fine-scale habitat characteristics (e.g., complexity, coral structure height, macroalgae presence) and the abundance, size structure, and behavior (rates of herbivory, tortuosity ratios and total distance travelled) of abundant parrotfish. Both seascape configuration and macroalgae influenced the patterns of fish abundance and rates of herbivory. However, these relationships varied with trophic groups and ontogenetic stages. Abundance of adult and intermediate-phase parrotfishes was positively influenced by densely aggregated coral structures, whereas juvenile abundance was positively influenced by the presence of macroalgae. Foraging path and bite rates of an abundant parrotfish, Chlorurus spilurus, were not influenced by coral structure configuration or height, but the presence of macroalgae increased the bite rates of all juvenile parrotfish. Our results suggest that a combination of seascape configuration, fine-scale habitat complexity, and microhabitat selectivity influence reef fish community structure and foraging behavior, thus altering herbivory. However, these relationships can differ among functional groups of fish and life-history stages. Information on these fish–habitat interactions is critical for identifying habitats that facilitate ecological functions and ensures the successful management and conservation of essential habitats.