Abstract The metabolic processes sustaining coral reefs, from carbonate and primary production to secondary production, remain poorly integrated and rarely quantified simultaneously at global scales. This hampers our ability to predict global responses to accelerating human pressures and manage coral reef functioning. Using metabolic scaling and bioenergetic models applied to surveys from 1,100 reefs worldwide, we provide a global, standardized quantification of 14 ecosystem functions spanning benthic (corals and algae) and fish communities. Our analysis reveals a continuous functional spectrum of global coral reefs organized along four dominant axes: 1) primary production, 2) calcification and habitat structure, 3) secondary biomass production and consumption, and 4) biomass turnover. Functions mediated by fish and benthic communities show weak associations at the global scale rather than tight coupling. Climate stressors reduced calcification and local human impacts lowered secondary production. Yet these directional effects unfolded against a backdrop of substantial natural variability in reef functional configurations, such that heavily and minimally impacted reefs overlap substantially in the global functional space. Temporal analyses across three representative reef systems further revealed that functional trajectories following disturbance are context-dependent, with no universal pattern of recovery across locations. This continuous and context-dependent functional spectrum challenges the notion of universal functional benchmarks and supports locally tailored conservation strategies.

The growing adoption of technology is reshaping how coral reef fish communities are surveyed, with implications for biodiversity monitoring and interpretation. Although confidence in newer methods has increased, key gaps remain in understanding how survey approaches influence observed community patterns across reefs with different ecological characteristics. We compared 3 survey methods (underwater visual census [UVC], a time-extended stereo-video protocol [SVS10], and a standard diver-operated stereo-video [SVS2] across 2 biogeographically distinct coral reef regions in Honduras and Indonesia. Our aim was to assess how survey method and survey effort (defined here as the duration taken to complete a fixed-length transect) affect fish community composition, and how these effects differ between regions. Using multivariate analyses, we found that both survey method and effort significantly influenced the observed community structure in both regions. UVC recorded the highest abundance and species richness, followed by SVS10 and SVS2, with each method sampling a distinct subset of the fish community. While overall patterns were consistent between regions, the magnitude of differences between methods varied substantially, indicating that method performance is not consistent across locations. Our findings demonstrate that method selection has a measurable impact on reef fish assemblage data. While UVC remains the most reliable method for detecting a broad range of species, the suitability of diver-operated stereo-video approaches depends on local conditions as well as research aims and logistical constraints. As stereo-video becomes more widely adopted, careful consideration of these trade-offs is essential for robust monitoring. Our results provide practical guidance to support effective survey design.

Signals mediate a range of behavioural interactions with important fitness implications within and between species. However, compared to our knowledge about how signals convey information and remain reliable within species, much less is known for interspecific signalling. One interspecies interaction mediated by signals are cleaning mutualisms in which cleaner shrimp remove parasites from their reef fish clients. The Pederson cleaner shrimp, Ancylomenes pedersoni, signals its intent to clean clients by whipping its long, white antennae, which is usually followed by cleaning. Based on the assumption that intent to clean is driven by hunger, we hypothesized that shrimp advertise willingness to clean based on their own hunger level, with hungrier shrimp being more willing to signal (and clean) than satiated ones. Here, we present support for this hypothesis from both the field and laboratory. First, we annotated field videos collected in Cura & ccedil;ao and Honduras, and found that the likelihood of antennae whipping and cleaning increased as time since last clean increased (with more time passing presumably leading to the shrimp being hungrier). In the laboratory, we manipulated the hunger levels of captive A. pedersoni and exposed them to a visual stimulus of a client fish. We found that the proportion of interactions in which shrimp antennae-whipped and cleaned was significantly greater when shrimp were hungry, compared to when satiated. Interestingly, we also found that signal honesty, how often shrimp followed signalling with cleaning, was less variable in hungry versus satiated shrimp. These results indicate that hunger level influences the signalling and cleaning behaviour of cleaner shrimp, revealing a mechanism underlying the information content of cleaning advertisement signals in A. pedersoni and suggesting a link between hunger level and signal honesty. Overall, this study provides insight into the interspecies signalling that maintains an important mutualistic relationship. (c) 2026 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights are reserved, including those for text and data mining, AI training, and similar technologies.

Fish communities at greater depths on a reef are thought to be less affected by disturbances that more strongly impact shallower areas. As a result, these deeper communities might be expected to show less change in their diversity and composition over time compared to those in shallow water. To test this hypothesis, we analysed changes in reef fish composition at 5-15 m and 25-40 m on reefs around Utila, Honduras, across two time periods: 2014-2015 and 2022-2023. We estimated taxonomic and functional α- and β- diversity using coverage-based standardisation and Hill-Chao numbers at orders q = 0 (species richness) and q = 2 (inverse Simpson index). Results showed that the α-diversity of fish communities was more consistent at 25-40 m than at shallower depths between the two time periods. However, β-diversity of dominant species and traits (q = 2) increased at greater depths, indicating that deeper fish communities became more distinct from one another in both structure and function, as well as more different from shallower communities at the same sites. Changes in diversity also varied between sites, highlighting the role of sitespecific conditions in shaping and maintaining fish communities across depths. Overall, the findings are not consistent with the expectation that greater depth reduces temporal community variability, and they raise questions about whether depth alone can serve as a refuge for reef fish.

Aggressive territoriality can have significant benefits for resource acquisition yet is a costly behaviour. Selection should therefore favour mechanisms that allow individuals to modify their behaviour to maintain and defend their territory whilst minimising costs. One such mechanism between intraspecific territorial competitors is neighbour-stranger discrimination. The familiarity hypothesis suggests that territory holders will respond less aggressively to neighbours they recognise than to strangers they do not recognise. Conversely, in systems where neighbours pose a greater threat to territory loss than strangers, the threat-level hypothesis predicts that neighbours will elicit a greater aggressive response. We tested these opposing hypotheses in territorial farming damselfishes Stegastes diencaeus using a common bottle presentation experiment design to initiate aggressive responses by territory holders to neighbouring and non-neighbour individuals. Neighbours that were smaller in body size than the territory holder elicited the greatest aggressive response, whereas larger neighbours elicited the weakest. The aggressive response elicited by non-neighbours did not vary greatly with body size difference between the stimulus fish and territory holder. We demonstrate that aggressive response in territorial farming damselfishes is influenced by both familiarity and potential threat determined by body size. These findings add to the growing pool of evidence that an understanding of multiple factors is needed to identify the drivers of neighbour-stranger discrimination. Both familiarity and body size may mediate aggressive behaviour yet are not often included in the same study. Using manipulative field experiments, we investigated the interplay between familiarity and body size in shaping patterns of aggressive behaviour in farming damselfishes. We found that territory holders were less aggressive towards neighbours than non-neighbours, but only when they were larger than themselves. Our results showing an interaction between the effects of familiarity and body size on aggressive behaviour may hint at nuances in patterns of neighbour-stranger discrimination, such as dominance relationships.

The three-dimensional (3D) structure of habitats influences how prey detect and respond to predators, but the specific roles of different aspects of structural complexity remain poorly understood, particularly in coral reef ecosystems. We used 3D models of 3 Caribbean reef sites to quantify 3 structural metrics at site level: field of view (the extent of observable area), refuge density (density of holes), and rugosity (reef surface roughness). We then observed the anti-predator behavior of damselfish, parrotfish, and wrasses at each site. Territorial damselfish showed species-specific responses to habitat structure, especially in relation to field of view. Stegastes adustus, for example, exhibited shorter flight initiation distances (FIDs) at the site with the highest field of view, consistent with expectations from optimal escape theory. In contrast, wrasse and parrotfish species showed little variation in behavior across sites, though larger individuals tended to have longer FIDs and flight distances. Refuge density was similar across sites, likely reflecting long-term regional loss of fine-scale complexity in the Caribbean. While rugosity is widely used as a proxy for reef complexity, our results suggest that field of view may be more strongly associated with differences in anti-predator behavior, particularly in damselfish. These findings highlight the need to assess multiple dimensions of habitat structure, as even closely related species may exhibit distinct behavioral adaptations to their 3D environment.

MotivationHere, we make available a second version of the BioTIME database, which compiles records of abundance estimates for species in sample events of ecological assemblages through time. The updated version expands version 1.0 of the database by doubling the number of studies and includes substantial additional curation to the taxonomic accuracy of the records, as well as the metadata. Moreover, we now provide an R package (BioTIMEr) to facilitate use of the database.Main Types of Variables IncludedThe database is composed of one main data table containing the abundance records and 11 metadata tables. The data are organised in a hierarchy of scales where 11,989,233 records are nested in 1,603,067 sample events, from 553,253 sampling locations, which are nested in 708 studies. A study is defined as a sampling methodology applied to an assemblage for a minimum of 2 years.Spatial Location and GrainSampling locations in BioTIME are distributed across the planet, including marine, terrestrial and freshwater realms. Spatial grain size and extent vary across studies depending on sampling methodology. We recommend gridding of sampling locations into areas of consistent size.Time Period and GrainThe earliest time series in BioTIME start in 1874, and the most recent records are from 2023. Temporal grain and duration vary across studies. We recommend doing sample-level rarefaction to ensure consistent sampling effort through time before calculating any diversity metric.Major Taxa and Level of MeasurementThe database includes any eukaryotic taxa, with a combined total of 56,400 taxa.Software Formatcsv and. SQL.

AimEcological state shifts that alter the structure and function of entire ecosystems are a concerning consequence of human impact. Yet, when, where and why discrete ecological states emerge remains difficult to predict and monitor, especially in high-diversity systems. We sought to quantify state shifts and their drivers through space and time in the most ecologically complex marine ecosystem: tropical coral reefs.LocationWorldwide.Time Period1987-2019.Major Taxa StudiedCoral reef communities.MethodsUsing a global dataset of 3375 coral reef surveys, along with 13 time series datasets ranging between 1987 and 2019, we applied a novel double-dichotomy approach to classify coral reefs into four simplified and discrete states based on the relative contributions of corals versus algae to benthic cover and small-bodied versus large-bodied fishes to fish standing stock. We then examined state shifts considering a range of spatial predictors and tested whether states have shifted directionally over time, and the nature of the most common transitions.ResultsWe show that geographic, environmental and anthropogenic context fundamentally shapes coral reef states at the local scale, which explains disparities among case studies, and stakes out critical baseline expectations for regional management efforts. We also reveal clear multi-decadal state shifts on coral reefs: over time, systems dominated by reef-building corals and small-bodied, planktivorous fishes tend to have been replaced with reefs characterised by algae and larger-bodied fishes.Main ConclusionsOur results suggest a previously unrecognised transition from systems that harness external subsidies through small-bodied consumers associated with structurally complex live corals, to herbivore-dominated systems with stronger bottom-up dynamics. Overall, the partitioning of complex reef ecosystems into a small suite of discrete ecological states suggests that spatial context-dependency, shifting baselines and changes in reef functioning are crucial considerations for coral reef management in the 21st century.

Interspecific interactions are fundamental drivers of animal space use. Yet while non-consumptive effects of predation risk on prey space use are well-known, the risk of aggressive interactions on space use of competitors is largely unknown. We apply the landscape of risk framework to competition-driven space use for the first time, with the hypothesis that less aggressive competitors may alter their behaviour to avoid areas of high competitor density. Specifically, we test how aggressive risk from territorial algal-farming damselfishes can shape the spatial distribution of herbivore fish competitors. We found that only the most aggressive damselfish had fewer competitors in their surrounding area, demonstrating that individual-level behavioural variation can shape spatial distributions. In contradiction to the landscape of risk framework, abundances of farming damselfish and other fishes were positively associated. Our results suggest that reef fishes do not simply avoid areas of high damselfish abundance, but that spatial variation in aggressive behaviour, rather than of individuals, created a competitive landscape of risk. We emphasize the importance of individual-level behaviour in identifying patterns of space use and propose expanding the landscape of risk framework to non-predatory interactions to explore cascading behavioural responses to aggressive risk.

Biodiversity drives stability in communities, allowing it to withstand environmental fluctuations without changes in aggregate properties like total abundance or biomass. We investigated biodiversity’s influence on two crucial population-level mechanisms governing abundance stability in mesopredatory coral reef fishes: ‘community asynchrony,’ where species populations fluctuate inversely over time, and ‘dominant stability,’ where highly abundant species with significant community contributions display minimal population fluctuations. Analyzing data from 83 reef fish communities across the Indian and Pacific Oceans over a decade, we found that community asynchrony, rather than dominant stability, primarily predicts community stability. Functional diversity, not taxonomic diversity, regulates this stability, emphasizing the role of niche differences in stabilizing communities. We highlight that community attributes that promote asynchronous population fluctuations, enhancing response diversity and tempering strong trophic interactions are vital for stabilizing mesopredatory reef fish communities in the face of global change.

Recreational SCUBA diving is widespread and increasing on coral reefs worldwide. Standard open-circuit SCUBA equipment is inherently noisy and, by seeking out areas of high biodiversity, divers inadvertently expose reef communities to an intrusive source of anthropogenic noise. Currently, little is known about SCUBA noise as an acoustic stressor, and there is a general lack of empirical evidence on community-level impacts of anthropogenic noise on coral reefs. Here, we conducted a playback experiment on Caribbean reefs to investigate impacts of SCUBA noise on fish communities and interspecific cooperation at ecologically important cleaning stations of the Pederson’s cleaner shrimp Ancylomenes pedersoni . When exposed to SCUBA-noise playback, the total occurrence of fishes at the cleaning stations decreased by 7%, and the community and cleaning clientele compositions were significantly altered, with 27% and 25% of monitored species being affected, respectively. Compared with ambient-sound playback, SCUBA-noise playback resulted in clients having to wait 29% longer for cleaning initiation and receiving 43% less cleaning; however, cheating, signalling, posing and time spent cleaning were not affected by SCUBA-noise playback. Our study is the first to demonstrate experimentally that SCUBA noise can have at least some negative impacts on reef organisms, confirming it as an ecologically relevant pollutant. Moreover, by establishing acoustic disturbance as a likely mechanism for known impacts of diver presence on reef animals, we also identify a potential avenue for mitigation in these valuable ecosystems.

AimEcological refuges buffer organisms against stressors and mediate a range of species interactions. However, their role in the context of biological invasions has yet to be synthesized, despite the increasing prevalence and impact of non-native species. To address this, we conducted a systematic review aiming to determine the extent to which refuges are considered explicitly in the invasion literature and to synthesize their function. LocationGlobal. Time periodPresent day. Major taxa studiedAll. MethodsOur search of the literature was conducted using the SCOPUS and Web of Science databases and followed the preferred reporting items for systematic reviews and meta-analyses (PRISMA) protocol. We obtained 315 records of refuge use in biological invasions from 300 studies. From each record, we extracted information relating to the experimental design, species characteristics and refuge type, where available. ResultsRefuges and refuge-mediated processes are widely reported in the invasion literature. Native species commonly use refuges to avoid non-native predation and competition, with spatial complexity and habitat heterogeneity key factors in facilitating their coexistence. Records show that artificial structures safeguard non-natives in their introduced range. However, there were key differences in the use of such structures in marine and terrestrial environments. Moreover, the enhanced structural complexity created by non-native plants and bivalves is often reported to act as a predation refuge for other species. Main conclusionsThe ubiquity of refuge-based processes suggests that refuges can play an important role in affecting the persistence, spread and impacts of non-native species, either through previously described mechanisms (i.e. refuge-mediated apparent competition and the persistent pressure scenario) or through a mechanism we describe (i.e. when non-native species use existing refuges), or both.

AimBiodiversity loss is impacting essential ecosystem functions and services across the globe. Recently, our interest in the benefits of biodiversity for ecosystem function has shifted focus from measurements of species richness to functional diversity and composition. However, the additional importance of other community characteristics, such as species evenness and co-occurrence, for diversity-driven ecosystem function is less known. We used herbivorous coral reef fish as a model system to investigate how co-occurrence of different functional groups, rather than purely functional diversity, within an assemblage might affect the coral reef benthic state. LocationWestern Atlantic. Time period2007-2017. Major taxa studiedHerbivorous reef fish. MethodsWe analysed benthic and fish assemblage data from 601 sites across 12 countries in the western Atlantic. Using diversity-interaction models, we investigated how the composition and relative abundances of reef fish functional groups were correlated with benthic cover and estimates of coral calcification rates. We used statistical interactions to explore the importance of co-occurrence of herbivorous fish functional groups for the coral reef benthic state. ResultsWe found that co-occurrence of herbivorous fish functional groups, in addition to functional diversity, was correlated with reduced algal cover and increased coral accretion. Moreover, pairwise statistical interactions between functional groups were significantly correlated with an improvement in the coral reef benthic state. Main conclusionsOur results support the idea that functional group co-occurrence, in addition to functional diversity, within herbivorous fish offers additional benefits to the coral reef benthic state. We identify farming damselfish and excavating parrotfish as potential key determinants of the coral reef benthic state and highlight that co-occurrence of cropping and scraping herbivores might promote coral accretion. Our findings support the argument that protecting herbivore abundance without regard to the species and functional groups present is not enough to preserve coral reef health and that fine-scale community composition must be considered.

Rising ocean temperatures are the primary driver of coral reef declines throughout the tropics. Such declines include reductions in coral cover that facilitate the monopolization of the benthos by other taxa such as macroalgae, resulting in reduced habitat complexity and biodiversity. Long-term monitoring projects present rare opportunities to assess how sea surface temperature anomalies (SSTAs) influence changes in the benthic composition of coral reefs across distinct locations. Here, using extensively monitored coral reef sites from Honduras (in the Caribbean Sea), and from the Wakatobi National Park located in the center of the coral triangle of Indonesia, we assess the impact of global warming on coral reef benthic compositions over the period 2012-2019. Bayesian generalized linear mixed effect models revealed increases in the sponge, and hard coral coverage through time, while rubble coverage decreased at the Indonesia location. Conversely, the effect of SSTAs did not predict any changes in benthic coverage. At the Honduras location, algae and soft coral coverage increased through time, while hard coral and rock coverage were decreasing. The effects of SSTA at the Honduras location included increased rock coverage, but reduced sponge coverage, indicating disparate responses between both systems under SSTAs. However, redundancy analyses showed intralocation site variability explained the majority of variance in benthic composition over the course of the study period. Our findings show that SSTAs have differentially influenced the benthic composition between the Honduras and the Indonesian coral reefs surveyed in this study. However, the large intralocation variance that explains the benthic composition at both locations indicates that localized processes have a predominant role in explaining benthic composition over the last decade. The sustained monitoring effort is critical for understanding how these reefs will change in their composition as global temperatures continue to rise through the Anthropocene.

Research in global change ecology relies heavily on global climatic grids derived from estimates of air temperature in open areas at around 2 m above the ground. These climatic grids do not reflect conditions below vegetation canopies and near the ground surface, where critical ecosystem functions occur and most terrestrial species reside. Here, we provide global maps of soil temperature and bioclimatic variables at a 1‐km 2 resolution for 0–5 and 5–15 cm soil depth. These maps were created by calculating the difference (i.e. offset) between in situ soil temperature measurements, based on time series from over 1200 1‐km 2 pixels (summarized from 8519 unique temperature sensors) across all the world's major terrestrial biomes, and coarse‐grained air temperature estimates from ERA5‐Land (an atmospheric reanalysis by the European Centre for Medium‐Range Weather Forecasts). We show that mean annual soil temperature differs markedly from the corresponding gridded air temperature, by up to 10°C (mean = 3.0 ± 2.1°C), with substantial variation across biomes and seasons. Over the year, soils in cold and/or dry biomes are substantially warmer (+3.6 ± 2.3°C) than gridded air temperature, whereas soils in warm and humid environments are on average slightly cooler (−0.7 ± 2.3°C). The observed substantial and biome‐specific offsets emphasize that the projected impacts of climate and climate change on near‐surface biodiversity and ecosystem functioning are inaccurately assessed when air rather than soil temperature is used, especially in cold environments. The global soil‐related bioclimatic variables provided here are an important step forward for any application in ecology and related disciplines. Nevertheless, we highlight the need to fill remaining geographic gaps by collecting more in situ measurements of microclimate conditions to further enhance the spatiotemporal resolution of global soil temperature products for ecological applications.

Coral reef ecosystems have been rapidly altered by anthropogenic warming, posing significant threats to marine biodiversity. However, alterations of the benthic configurations of coral reefs under global warming likely vary through space given local-scale variation in environmental conditions and ecosystem processes. Here, we examine the responses of coral reef benthic configurations under global warming in two independent coral reef ecosystems from Honduras and Indonesia. Using Monte Carlo Markov Chain Generalised Linear Mixed models, our findings reveal that at the Honduras sites, global warming significantly drove reductions in sand, sponge and coral rubble coverage, while bare rock coverage increased. Conversely, the Indonesia sites only showed increases in sponge coverage and decreases in rock coverage associated with water warming. These strong disparities seem to have been driven by global warming only at the Honduras sites, but not at the Indonesia sites. This suggests that the Indonesia sites of the Wakatobi National Park (WNP) may be resistant to compositional changes under global warming. We suspect the resistance to compositional change at the WNP is driven by disparate ecosystem processes between the Honduras and Indonesia sites which enhances resilience to disturbance, such as water warming. Furthermore, there is potential indication that abiotic processes comparatively shelter coral reefs of the WNP from rising temperatures, however, this facet would need further exploration. Given the resistance to compositional change of coral reefs within the WNP, this region could potentially harbour critical biodiversity as global warming continues to decimate coral reefs throughout the tropics.

Coral reef metabolism underpins ecosystem function and is defined by the processes of photosynthesis, respiration, calcification, and calcium carbonate dissolution. However, the relationships between these physiological processes at the organismal level and their interactions with light remain unclear. We examined metabolic rates across a range of photosynthesising calcifiers in the Caribbean: the scleractinian corals Acropora cervicornis, Orbicella faveolata, Porites astreoides, and Siderastrea siderea, and crustose coralline algae (CCA) under varying natural light conditions. Net photosynthesis and calcification showed a parabolic response to light across all species, with differences among massive corals, branching corals, and CCA that reflect their relative functional roles on the reef. At night, all organisms were net respiring, and most were net calcifying, although some incubations demonstrated instances of net calcium carbonate (CaCO3) dissolution. Peak metabolic rates at light‐saturation (maximum photosynthesis and calcification) and average dark rates (respiration and dark calcification) were positively correlated across species. Interspecies relationships among photosynthesis, respiration, and calcification indicate that calcification rates are linked to energy production at the organismal level in calcifying reef organisms. The species‐specific ratios of net calcification to photosynthesis varied with light over a diurnal cycle. The dynamic nature of calcification/photosynthesis ratios over a diurnal cycle questions the use of this metric as an indicator for reef function and health at the ecosystem scale unless temporal variability is accounted for, and a new metric is proposed. The complex light‐driven dynamics of metabolic processes in coral reef organisms indicate that a more comprehensive understanding of reef metabolism is needed for predicting the future impacts of global change.

Benthic incubation chambers facilitate in-situ metabolism studies in shallow water environments. They are used to isolate the water surrounding a study organism or community so that changes in water chemistry can be quantified to characterise physiological processes such as photosynthesis, respiration, and calcification. Such field measurements capture the biological processes taking place within the benthic community while incorporating the influence of environmental variables that are often difficult to recreate in ex-situ settings. Variations in benthic chamber designs have evolved for a range of applications. In this study, we built upon previous designs to create a novel chamber, which is (1) low-cost and assembled without specialised equipment, (2) easily reproducible, (3) minimally invasive, (4) adaptable to varied substrates, and (5) comparable with other available designs in performance. We tested the design in the laboratory and field and found that it achieved the outlined objectives. Using non-specialised materials, we were able to construct the chamber at a low cost (under $20 USD per unit), while maintaining similar performance and reproducibility with that of existing designs. Laboratory and field tests demonstrated minimal leakage (2.08 ± 0.78% water exchange over 4 h) and acceptable light transmission (86.9 ± 1.9%), results comparable to those reported for other chambers. In the field, chambers were deployed in a shallow coastal environment in Akumal, Mexico, to measure productivity of seagrass, and coral-, algae-, and sand-dominated reef patches. In both case studies, production rates aligned with those of comparable benthic chamber deployments in the literature and followed established trends with light, the primary driver of benthic metabolism, indicating robust performance under field conditions. We demonstrate that our low-cost benthic chamber design uses locally accessible and minimal resources, is adaptable for a variety of field settings, and can be used to collect reliable and repeatable benthic metabolism data. This chamber has the potential to broaden accessibility and applications of in-situ incubations for future studies.

Benthic incubation chambers facilitate in-situ metabolism studies in shallow water environments.They are used to isolate the water surrounding a study organism or community so that changes in water chemistry can be quantified to characterise physiological processes such as photosynthesis, respiration, and calcification.Such field measurements capture the biological processes taking place within the benthic community while incorporating the influence of environmental variables that are often difficult to recreate in ex-situ settings.Variations in benthic chamber designs have evolved for a range of applications.In this study, we built upon current designs to create a novel chamber, which is (1) low-cost and assembled without specialised equipment, (2) easily reproducible, (3) minimally invasive, (4) adaptable to varied substrates, and (5) comparable with other available designs in performance.We tested the design in the laboratory and field and found that it achieved the outlined objectives.Using nonspecialised materials, we were able to construct the chamber at a low cost (under $20 USD per unit), while maintaining similar performance and reproducibility with that of existing designs.Laboratory and field tests demonstrated minimal leakage (2.08 ± 0.78 % water exchange over 4 hours) and acceptable light transmission (86.9 ± 1.9 %), results comparable to those reported for other chambers.In the field, chambers were deployed in a shallow coastal environment in Akumal, Mexico, to measure productivity of (a) seagrass, and (b) coral-, algae-, and sand-dominated reef patches.In both case studies, production rates aligned with those of comparable benthic chamber deployments in the literature and followed established trends with light, the primary driver of benthic metabolism, indicating robust performance under field conditions.We demonstrate that our low-cost benthic chamber design uses locally accessible and minimal resources, is adaptable for a variety of