Guilherme Ortigara Longo

• PhD
• Professor (Associate) at Federal University of Rio Grande do Norte

Numerous seaweeds produce secondary metabolites that are allelopathic to corals. To date, most of the compounds identified in this interaction are lipid-soluble instead of water-soluble. Thus, understanding whether these compounds are stored internally where they would not contact corals, or occur on external surfaces where they could be transferre...

Seaweed–coral interactions are increasingly common on modern coral reefs, but the dynamics, processes, and mechanisms affecting these interactions are inadequately understood. We investigated the frequency and effect of seaweed–coral contacts for common seaweeds and corals in Belize. Effects on corals were evaluated by measuring the frequency and e...

The Southwestern Atlantic harbors unique and relatively understudied reef systems, including the only atoll in South Atlantic: Rocas atoll. Located 230 km off the NE Brazilian coast, Rocas is formed by coralline red algae and vermetid mollusks, and is potentially one of the most "pristine" areas in Southwestern Atlantic. We provide the first compre...

Trophic interactions play a critical role in the structure and function of ecosystems. Given the widespread loss of biodiversity due to anthropogenic activities, understanding how trophic interactions respond to natural gradients (e.g., abiotic conditions, species richness) through large-scale comparisons can provide a broader understanding of thei...

This study compared remote underwater video and traditional direct diver observations to assess reef fish feeding impact on benthos across multiple functional groups within different trophic categories (e.g. herbivores, zoobenthivores and omnivores) and in two distinct reef systems: a subtropical rocky reef and a tropical coral reef. The two techni...

The origin of most reef biodiversity of the southwestern Atlantic Ocean dates back to the Eocene, when the center of diversity of modern reef organisms was in the Tethys Sea, a vast extent of tropical shallow marine habitats situated between the Atlantic and Indian oceans. Following the closure of the Tethys Sea, the Atlantic reef biodiversity beca...

Human activities and climate change have accelerated species losses and degradation of ecosystems to unprecedented levels. Both theoretical and empirical evidence suggest that extinction cascades contribute substantially to global species loss. The effects of extinction cascades can ripple across levels of ecological organization, causing not only...

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 sourc...

We collated hundreds of temperature time series from around the world’s oceans recorded at a frequency of 1 hour or less. Using these data, we tested for patterns in temperature variability across climate regions. Contrary to the climate variability hypothesis, which states that the temperature variability is highest in temperate regions and lowest...

The Brazilian marine biogeographical province (SW Atlantic) hosts coral and rocky reefs that cover ~27 degrees of latitude and are distributed along a relatively narrow continental shelf and four oceanic islands and archipelagos. The broad gradients in temperature, productivity and salinity shape patterns of biodiversity and lead to distinct local...

Coral–algal interactions are pivotal in reef ecosystems globally as they can scale up ecosystem levels and lead to dominance shifts. In this study, we conducted a systematic review of global coral–algal interactions, identifying the most studied locations, species, and types of interactions. We then assessed how these interactions may be impacted b...

Abiotic and biotic stressors are known to trigger reproductive activities in several aquatic organisms. In reef environments, physical contact as a response to competition for space on the benthos is a common stressor among sessile organisms, often leading to severe tissue damage and even mortality due to biological and chemical mechanisms. However...

The Southwestern Atlantic (SWA) harbors a relatively species poor but highly endemic coral assemblage due to historical processes, environmental and ecological drivers. Despite its low to moderate cover, corals still have a disproportionate contribution to ecosystem function and stability in this region. In the context of global change, it is imper...

Mass bleaching events are growing in duration and intensity. Besides causing extensive mortality, the progressively shorter time between events disrupts the ability of reefs to recover. The unique reefs of the Southwestern Atlantic are often considered climate refugia as they have suffered less bleaching-related mortality when compared to Indo–Paci...

Aim Predicting and acting on the future of ecosystems requires understanding species distribution shifts due to climate change. We investigated which corals are more likely to shift their distribution in the Southwestern Atlantic under a warming scenario. Location Southwestern Atlantic (SWA; 1° N–28° S). Methods We used spatial distribution model...

Space can be limited in reef ecosystems leading to competitive interactions among sessile organisms. Some competitive mechanisms can require physical contact while others operate with proximity between organisms. We investigated how the scleractinian coral Siderastrea stellata and the hydrocoral Millepora alcicornis respond to physical contact and...

Reef fisheries are multispecific and employ a variety of fishing gears across marine environments, even in remote areas. This intricate and multifaceted nature of reef fisheries is often overlooked in management strategies, leading to global management failures. In Brazil, information about reef fisheries is often scarce and scattered. This stems f...

The marine wildlife and seascape components of reef environments are part of peoples' senses and perceptions of nature and and ecosystem services. While people worldwide perceive and value reef components differently, such aesthetics evaluations often overlook marginal reefs, limiting our comprehensive understanding of their cultural significance....

Corals are colonial animals within the Phylum Cnidaria that form coral reefs, playing a significant role in marine environments by providing habitat for fish, mollusks, crustaceans, sponges, algae, and other organisms. Global climate changes are causing more intense and frequent thermal stress events, leading to corals losing their color due to the...

The emergence of functional ecology has changed the focus of ecological research from investigating patterns of species diversity to understanding how species traits relate to specific ecological processes generating these patterns. Traits, ecological patterns and processes can be shared and driven by species from distantly related taxonomic groups...

Portuguese version of a policy brief presented to SinBiose CNPq

Policy Brief presented to the SinBiose - CNPq

Abiotic and biotic factors are known drivers that modulate community assembly from a regional species pool. Recent evidence has highlighted the intrinsic role of phylogenetic history on communities' response to the environment. Understanding its exact role poses a challenge because community assembly is embedded in a spatio‐temporal context where d...

Aim Functional diversity encapsulates whole‐community responses to environmental gradients mediated by species traits. Under trait convergence, similar responses may cause distantly related taxa to exhibit spatially correlated functional diversity. We investigated whether similar responses of reef fish, coral and algal functional richness and dispa...

The TimeFISH database provides the first public time‐series dataset on reef fish assemblages in the southwestern Atlantic (SWA), comprising 15 years of data (2007–2022) based on standardized Underwater Visual Censuses (UVCs). The rocky reefs covered by our dataset are influenced by pronounced seasonal cycles of ocean temperatures with warm tropical...

Fish feeding on the benthos mediate important ecological processes in reef ecosystems that are threatened by several anthropogenic activities, including plastic pollution. The impacts of plastic pollution on reef ecological processes, such as herbivory, is still unclear. We experimentally tested in the field how the presence of plastic on the benth...

Biodiversity assessment is a mandatory task for sustainable and adaptive management for the next decade, and long-term ecological monitoring programs are a cornerstone for understanding changes in ecosystems. The Brazilian Long-Term Ecological Research Program (PELD) is an integrated effort model supported by public funds that finance ecological st...

Southwestern Atlantic reefs (Brazilian Province) occur along a broad latitudinal range (∼5°N-27°S) and under varied environmental conditions. We combined large-scale benthic cover and environmental data into uni- and multivariate regression tree analyses to identify unique shallow (<30 m) benthic reef communities and their environmental drivers alo...

Marginal reefs sustain coral assemblages under conditions considered suboptimal for most corals, resulting in low coral abundance. These reefs are inhabited by numerous fishes with a generally unknown degree of association with corals that might lead to the assumption that corals play minor roles in determining fish occurrence, when corals could be...

Marine herbivores may alter their behavior regarding habitat and food source choice according to the presence or absence of chemical cues from predators. To assess whether an amphipod species can detect and react to different water-soluble cues, individuals of Ampithoe marcuzzii were tested through a 2-current choice flume. Dual-response choice exp...

The marine aquarium trade often depends on organisms collected from reef environments. However, reefs are declining because of multiple anthropogenic stressors, and sustaining functional diversity is critical for maintaining reef resilience. Collection of organisms for the aquarium trade is growing in the Southwestern Atlantic, particularly in Braz...

Early naturalists suggested that predation intensity increases toward the tropics, affecting fundamental ecological and evolutionary processes by latitude, but empirical support is still limited. Several studies have measured consumption rates across latitude at large scales, with variable results. Moreover, how predation affects prey community com...

Early naturalists suggested that predation intensity increases toward the tropics, affecting fundamental ecological and evolutionary processes by latitude, but empirical support is still limited. Several studies have measured consumption rates across latitude at large scales, with variable results. Moreover, how predation affects prey community com...

Early naturalists suggested that predation intensity increases toward the tropics, affecting fundamental ecological and evolutionary processes by latitude, but empirical support is still limited. Several studies have measured consumption rates across latitude at large scales, with variable results. Moreover, how predation affects prey community com...

Early naturalists suggested that predation intensity increases toward the tropics, affecting fundamental ecological and evolutionary processes by latitude, but empirical support is still limited. Several studies have measured consumption rates across latitude at large scales, with variable results. Moreover, how predation affects prey community com...

Ocean warming is altering life on Earth from individuals to ecosystems. The impacts on standing biomass and food webs functioning are less evident due to the paucity of data and difficulty to generate reliable models. We modeled the food web of a tropical near-pristine reef ecosystem and analyzed changes on living biomass across trophic levels as a...

Coral reefs are in global decline due to unprecedented anthropogenic threats that have escalated and accumulated over decades to centuries. In order to assess the magnitude and drivers of changes on reefs, it is necessary to reconstruct the history of changes of these ecosystems over this longer time scale. We compiled and assessed historical recor...

Ocean warming is increasing the incidence, scale, and severity of global-scale coral bleaching and mortality, culminating in the third global coral bleaching event that occurred during record marine heatwaves of 2014-2017. While local effects of these events have been widely reported, the global implications remain unknown. Analysis of 15,066 reef...

In the tropical Atlantic Ocean, the Intertropical Convergence Zone (ITCZ) is an important climate feature controlled by the interhemispheric sea surface temperature (SST) gradient, and greatly influences rainfall patterns over the adjacent continents. To better understand ITCZ dynamics in the context of past and future climate change, long-term oce...

Although coral–algae competition is more widely and frequently studied, invertebrates are also major coral competitors, potentially influencing reef structural complexity. Ocean warming can affect the outcome of coral–algae interactions, but its effect on the competition between corals and other invertebrates is poorly understood. In Southwestern A...

Reefs are highly diverse ecosystems threatened by anthropogenic actions that change their structure and dynamics. Many of these changes have been witnessed by different reef users who hold specific knowledge about the reefscape according to their experiences and uses. We aimed to understand whether fishers, divers, and reef scientists have differen...

Subtropical Brazilian reefs are commonly composed by rocky frameworks with low coral abundance. Contrarily to most tropical reefs, our knowledge on coral assemblages in subtropical reefs is still developing. Queimada Grande is a subtropical island in the Brazilian coast lying 35 km offshore from the state of São Paulo (24ºS). Despite the partial pr...

In theoretical ecology, the quantity of resource consumed by a consumer per unit of time, defined as functional response, is of paramount importance. To better understand species interactions over time it is necessary to analyze whether consumer's functional response depends on resource density alone (which is the reference assumption) or on both r...

• Fisheries monitoring is essential to evaluate and manage fish populations. Effective monitoring is particularly challenging in low- and middle-income countries where fisheries often occur at large spatial scales and include multiple techniques. Recreational spearfishing, for instance, can be detrimental to fish populations and is often underrepre...

Global climate change is a major threat to reefs by increasing the frequency and severity of coral bleaching events over time, reducing coral cover and diversity. Ocean warming may cause shifts in coral communities by increasing temperatures above coral’s upper thermal limits in tropical regions, and by making extratropical regions (marginal reefs)...

Remote underwater videos are widely employed to assess the structure and composition of reef fish assemblages but the sampling effort employed on each survey differs considerably, indicating that both the number of assessments and video length could be optimized. We searched for this optimal sampling effort in remote video samples to conduct rapid...

In 2019, a major coral bleaching event affected reefs worldwide, including marginal reefs within the Abrolhos Bank (16°40′–19°40′S, 39°10′–37°20′W), the largest and richest coral reefs in the South Atlantic. Between March and May 2019, this area was affected by the strongest heatwave since 1985. The health trajectories of the branching hydrocoral M...

To assess whether amphipods' habitat choice and feeding preference for a specific seaweed species are based on nutritional value or structural complexity, and to evaluate the role of chemical cues in the amphipod choice, we carried out laboratory experiments using amphipods (Ampithoe marcuzzii) and seaweeds from different divisions (Chlorophyta, Oc...

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

The list of threatened species (Red List), established by the International Union for Conservation of Nature (IUCN), aims to provide global assessments on the extinction risk of species. However, protecting vulnerable populations requires establishing threat criteria at sub-global scales, e.g., national Red Lists. In data-poor contexts, typical of...

Scleractinian reef-building corals can lose their endosymbiotic photosynthetic dinoflagelates (Symbiodiniaceae) and bleach in response to drastic changes in environmental conditions, such as extreme temperature fluctuations and burial events. As bleaching episodes are becoming more frequent and intense worldwide, post-bleaching recovery is critical...

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 ecosyste...

Abstract Marine protected areas (MPAs) are a primary strategy for marine conservation worldwide, having as a common goal the protection of essential habitats to enhance fish population recovery. However, MPAs alone may not be effective because species are not isolated from critical impacts occurring outside their boundaries. We evaluated how protec...

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 ecosyste...

Interactions among species are likely to change geographically due to climate‐driven species range shifts and in intensity due to physiological responses to increasing temperatures. Marine ectotherms experience temperatures closer to their upper thermal limits due to the paucity of temporary thermal refugia compared to those available to terrestria...

Many Caribbean reefs have shifted from coral dominance to macroalgal dominance, often by brown algae such as Dictyota and Lobophora. However, the north side of Cayman Brac in the Cayman Islands is dominated seasonally by the green macroalga Microdictyon (percent cover of Microdictyon is 4% in the winter and ~40% of the reef in the summer), although...

Coral reefs have changed radically in the last few decades with reefs in the Caribbean now averaging 13% coral cover and 40% macroalgal cover (mostly Dictyota and Lobophora). So, it is time we re-evaluate which species are key to the process of herbivory in these new conditions. The role herbivorous fishes play in controlling macroalgae is often co...

Oceans absorb a huge part of the atmospheric heat, leading to the rise in water temperature. Reefs are among the most affected ecosystems, where the complex behavioral repertoire of fishes is usually an indicator of environmental impacts. Here, we examined whether temperature (28 and 34°C) and habitat complexity (high and low) interact to affect th...

Mass coral bleaching has increased in intensity and frequency and has severely impacted shallow tropical reefs worldwide. Although extensive investigation has been conducted on the resistance and resilience of coral reefs in the Indo-Pacific and Caribbean, the unique reefs of the South Atlantic remain largely unassessed. Here we compiled primary an...

Understanding the interplay between processes operating at large and small spatiotemporal scales in shaping biotic interactions remains challenging. Recent studies illustrate how phenotypic specialization, species life‐history traits and/or resource partitioning recurrently underlie the structure of mutualistic interactions in terrestrial ecosystem...

Species interactions can modulate the diversity and enhance the stability of biological communities in aquatic ecosystems. Despite previous efforts to describe fish interactions in tropical rivers, the role of habitat characteristics, community structure, and trophic traits over these interactions is still poorly understood. To investigate among-ha...

Many parrotfishes (Labridae: Scarinae) have life history traits, including late maturation and long lifespans, that make them vulnerable to overfishing. The greenbeak parrotfish Scarus trispinosus is the largest Brazilian endemic parrotfish and has been harvested in reef-associated fisheries along the coast. After a sharp population decline, S. tri...

Overfishing, pollution and global changes threaten reef ecosystems all over the world and several conservation actions emerged to reduce and mitigate such impacts. Citizen-based programs with hands-on conservation experience and voluntarily data collection are a successful way of involving society in the conservation process. We developed and teste...

Parrotfishes may affect the structure of benthic communities and reef ecosystem functioning. Despite extensive studies worldwide, parrotfishes in the southwestern Atlantic are relatively understudied, limiting our ability to propose effective management strategies. We assessed abundance, biomass and size class distribution of parrotfish assemblages...

Aim The aim was to evaluate the hypothesis that biotic interactions are more intense in the tropics using reef fishes (from both functional and taxonomic perspectives), the crucial consumers on most reefs. Location Fifteen reef locations between 34°N and 27°S in the Western Atlantic. Time period 2011–2014. Major taxa studied Reef fishes. Method...

The Long-Term Monitoring Program of Brazilian OceanicIslands (PELD-ILOC), whose main goal is monitoring various components of the reef environments in the Brazilian oceanic island, started its activities in 2013. During the last five years, researchers have been gathering data on reef fish assemblages, benthic communities, coral health and its as...

As marine ecosystems are influenced by global and regional processes, standardized information on community structure has become crucial for assessing broad-scale responses to natural and anthropogenic disturbances. Extensive biogeographic provinces, such as the Brazilian Province in the southwest Atlantic, present numerous theoretical and methodol...

Classification of taxa and benthic group related. (PDF)

Summary of field effort at the sites along the Brazilian Province. FN = Fernando de Noronha, PML = Parcel do Manuel Luis, BTS = Baia de Todos os Santos. (PDF)

nMDS ordination with the benthic community composition. (A) sites only with both depth strata; (B) all sites surveyed. Black squares are the organisms. FN = Fernando de Noronha, PML = Parcel do Manuel Luis and BTS = Baia de Todos os Santos. (EPS)

Species accumulation curves using observed taxa (Sobs) and Chao estimator. (EPS)

The Sisbiota-mar photoquadrat survey aims to quantify the benthic cover of horizontal reef surfaces using photography and subsequent image analysis, in a manner that is directly comparable across geographies. Our survey method employs 2m2 horizontal surfaces of reef area at 1-7 meters (shallow) and 8-15 meters (deep). At each locality, between one...

Coral reefs are degrading to algae-dominated reefs worldwide, with alterations of coral microbiomes commonly co-occurring with reef demise. The severe thermal anomaly during the 2016 El Niño event in the South Pacific killed many corals and stressed others. We examined the microbiome of turf algae and of the coral Porites sp. in contact with turf d...