Epibenthic species traits demonstrate how macroalgal decline degrades temperate reef function

Epibenthic species traits demonstrate how macroalgal decline degrades temperate reef function | Authorea try { document.documentElement.classList.add('js'); } catch (e) { } var _gaq = _gaq || []; _gaq.push(['_setAccount', 'G-8VDV14Y67G']); _gaq.push(['_trackPageview']); (function() { var ga = document.createElement('script'); ga.type = 'text/javascript'; ga.async = true; ga.src = ('https:' == document.location.protocol ? 'https://ssl' : 'http://www') + '.google-analytics.com/ga.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(ga, s); })(); Skip to main content Preprints Collections Wiley Open Research IET Open Research Ecological Society of Japan All Collections About About Authorea FAQs Contact Us Quick Search anywhere Search for preprint articles, keywords, etc. Search Search ADVANCED SEARCH SCROLL This is a preprint and has not been peer reviewed. Data may be preliminary. 12 March 2025 V1 Latest version Share on Epibenthic species traits demonstrate how macroalgal decline degrades temperate reef function Authors : Jared Oviatt 0009-0006-3521-4473 [email protected] , Matthew McLean , Melissa LaCroce , and D Freshwater Authors Info & Affiliations https://doi.org/10.22541/au.174177575.50262279/v1 Published Marine Ecology Progress Series Version of record Peer review timeline 202 views 307 downloads Contents Abstract Information & Authors Metrics & Citations View Options References Figures Tables Media Share Abstract Understanding how changing biological communities will impact ecosystem function is critical for projecting future dynamics and maintaining resilient ecosystems. Trait-based ecology can provide a clearer mechanistic understanding of a system useful for predicting biological changes and potential impacts for ecosystem functioning. Here we apply a novel set of functional traits to epibenthic organisms which, to our knowledge, have not been assessed in this way. We then use these traits to compare an epibenthic community from a North Carolina hard bottom reef over two consecutive years to demonstrate the utility of this trait-based method and to explore implications of a changing epibenthic community. We find that both taxonomic and trait community structure differed between the summers of 2016 and 2017, yet there was little change in either taxonomic or trait diversity. From 2016 to 2017, communities shifted from tall, uncalcified primary producers to short, calcified consumers. We suggest this shift represents an overall loss of reef functions, such as reduced biogenic habitat provisioning and primary production, and that these were driven primarily by the loss of major macroalgae not replaced by other taxa. This ability to assess species traits inclusive of invertebrates and macroalgae will have broad implications for reef ecology under climate change where algal-invertebrate phase-shifts are increasingly common. Epibenthic species traits demonstrate how macroalgal decline degrades temperate reef function Abstract Understanding how changing biological communities will impact ecosystem function is critical for projecting future dynamics and maintaining resilient ecosystems. Trait-based ecology can provide a clearer mechanistic understanding of a system useful for predicting biological changes and potential impacts for ecosystem functioning. Here we apply a novel set of functional traits to epibenthic organisms which, to our knowledge, have not been assessed in this way. We then use these traits to compare an epibenthic community from a North Carolina hard bottom reef over two consecutive years to demonstrate the utility of this trait-based method and to explore implications of a changing epibenthic community. We find that both taxonomic and trait community structure differed between the summers of 2016 and 2017, yet there was little change in either taxonomic or trait diversity. From 2016 to 2017, communities shifted from tall, uncalcified primary producers to short, calcified consumers. We suggest this shift represents an overall loss of reef functions, such as reduced biogenic habitat provisioning and primary production, and that these were driven primarily by the loss of major macroalgae not replaced by other taxa. This ability to assess species traits inclusive of invertebrates and macroalgae will have broad implications for reef ecology under climate change where algal-invertebrate phase-shifts are increasingly common. Keywords: functional traits, trait ecology, algae, invertebrates, benthic ecology, reef ecology INTRODUCTION Temperate reefs support diverse and productive biological communities and are well known for their aggregations of economically and ecologically important reef fish species, such as those in the snapper-grouper complex (Kendall et al. 2009, Lindeman et al. 2009, Paxton 2018). Extensive interconnected networks of hard bottom reef habitat maintain fish distributions throughout the South Atlantic Bight (SAB) (Steward et al. 2022). As localized biodiversity hotspots, these reefs provide habitat for residential fish species and breeding and foraging grounds for migratory fish species and large pelagic predators (Lindeman et al. 2009, Paxton et al. 2020, Bacheler et al. 2022). Shallow reefs in both temperate and tropical regions support populations of macroalgae and invertebrates, here referred to collectively as epibenthic organisms. As macroalgal and sessile invertebrate communities contribute to habitat structure and influence food webs, understanding their dynamics is key to a holistic view of temperate reef functioning. Macroalgae on temperate reefs provide dynamic, seasonal habitat structure and a source of primary production (Srednick and Steele 2019). Invertebrates, in contrast, are important primary and secondary consumers that aggregate nutrients and biomass from pelagic energy sources like phytoplankton production, particulate organic matter (POM), and dissolved organic matter (DOM) at a singular reef location (Coppari et al. 2019). Sessile invertebrates also provide physical habitat structure and tend to be more persistent than macroalgae (Layman and Allgeier 2020). Together, these two groups each contribute to reef functioning by mediating the total flux and aggregation of nutrients, biomass, material, and species in the local system (Brandl et al. 2019). Functions of epibenthic organisms Any organism can be defined by a set of ecological and biological traits that, when applied appropriately, may be analyzed as analogs for biological function (Laughlin 2014). By using an appropriate combination of traits, ecologists can assess how the dynamics of a biological community may be related to ecosystem functioning (Bellwood et al. 2019, Streit and Bellwood 2023).These trait-based approaches have now been applied extensively, first in plant ecology (Fukami et al. 2005), and later in other fields such as coral reef and fisheries ecology (e.g. Darling et al. 2017, McLean et al. 2019). Temperate reef functional trait ecology has garnered less attention, though with continued tropicalization (a shift toward warm-affinity species) of temperate reefs, understanding the spectra of temperate reef functioning in relation to biological communities is key to predicting how temperate reefs will respond to climate change. On temperate reefs, both macroalgal and sessile invertebrates have the potential to be dominant (Peckol and Searles 1984, LaCroce et al. 2020). However, very little research has attempted to encompass both groups under the umbrella of epibenthic ecology, and those who have tended to specialize in one group or the other. Because of this, there are independent trait data sets for macroalgae (Fong et al. 2023) and sessile invertebrates (Degen and Faulwetter 2019), with invertebrate traits adapted to include occasional macroalgae (Langlois et al. 2021), but to our knowledge there is no inclusive trait set that is designed to give equal consideration to macroalgae and sessile invertebrates. Currently, there is no standard definition for a functional trait that can be applied across epibenthic organisms. For fish and mobile invertebrates, perhaps the most studied marine communities, a functional trait pertains to the movement or storage of energy, material, and nutrients (Bellwood et al. 2019). For epibenthic organisms, the definition used for plant functional traits may be most appropriate, which are traits that influence an organism’s growth, survival, and reproduction (Violle et al. 2007). Here we discuss traits that are analogs for functions of habitat provisioning, energy flux and storage, palatability, contribution to reef accretion, reproduction, and dispersal because these all influence an organisms’ growth, reproduction, and survival, as well as their broader contribution to the reef function (Violle et al. 2007, Brandl et al. 2019, Anderson et al. 2022, Streit and Bellwood 2023). Temperate reef functioning under changing environmental regimes Macroalgal communities on warm temperate and subtropical reefs can be highly variable, responding to stochastic environmental processes such as nutrient fluxes from periodic upwelling and terrestrial runoff, mechanical disturbance from storms, light reduction from changes in turbidity, and in some locations, highly variable temperatures (Peckol 1982, Idol 2013, Short et al. 2015). Past work has demonstrated that often epibenthic invertebrates may not respond to the same disturbance regimes as macroalgae, allowing for oscillation between states of algal and invertebrate dominance (Irving and Connell 2002, LaCroce et al. 2018). Under conditions of high light and sufficient nutrients, macroalgae become the dominant overstory, but with low light and increased turbidity macroalgae are lost and sessile invertebrates become the predominant cover (Miller and Hay 1996, Oviatt et al. In press). Macroalgae and sessile invertebrates likely do not contribute equally to reef functioning. Therefore, understanding the implications of altered epibenthic community structure is critical to predicting how changing ecosystems may alter the breadth of temperate reef functioning. Tropicalization is often driven by the arrival of tropical species to temperate communities, yet it may also result from the loss of cold temperate species (McLean et al. 2021). Marine macroalgae are some of the most susceptible to this change, with many areas seeing ongoing loss of large fleshy macroalgae and the habitat they provide (Thomsen et al. 2019, Berry et al. 2021). In cold temperate environments, charismatic macroalgae such as Nereocystis luetkeana , Macrocystis pyrifera , and Durvillaea spp. may clearly be thought of as ‘functionally distinct’. However, in regions where the largest macroalgae are only a meter tall at their peak, it is worth considering if height is the main and only way these organisms differ from their neighboring epibenthos. Similarly, it may be important to consider that other, less charismatic, and therefore less studied, organisms may be functionally distinct within that community (Violle et al. 2017, Mouquet et al. 2024). North Carolina (United States) exists at the boundary between the subtropical and temperate zones of the western Atlantic and is therefore an important indicator region for warming temperate waters (Pappalardo et al. 2015). Additionally, the Gulf Stream is continually importing tropical spores, gametes, and larvae to North Carolina waters, some from species that are or may become invasive with topicalization (Paxton et al. 2019). This unique biogeographical transition zone supports unique biological communities not seen elsewhere, though there is still much work to be done to understand how these communities contribute to reef functioning and how the trait community structure compares to similar tropical-temperate bioregions throughout the world. Here we compare epibenthic community structure at a reef location in Onslow Bay, North Carolina, across two time points one year apart. Using these data, we aim to understand the functional trait community dynamics of the epibiota in the region. To do so, we ask the following questions : 1. Do epibenthic communities with and without major macroalgal taxa have similar or distinct trait community structure? 2. If these trait communities are distinct, which taxa and traits drive differences? 3. Does a shift in trait structure suggest a gain or loss of function? METHODS Diver surveys and community data collection The data for this project was adapted from diver surveys for LaCroce et al 2018 and 2020, which describe the methods in full detail. The authors provide an abbreviated description of these methods here. From May 2016 to September 2017, divers surveyed the epibenthic communities at 5 Mile Ledge, a hard bottom reef site approximately 5 miles from Masonboro Inlet in North Carolina (Fig. 1). The surveys were conducted at three replicate sites, 5- Mile A, B, and C, along three permanent transects. Images were taken within a 30cm x 30cm photoquadrat frame and then uploaded to CoralNet (Beijbom et al. 2015). The images were assessed for percent cover of organisms using a stratified random point intercept method with 72 points overlayed on each image. Organisms under each point were identified to the lowest taxonomic group possible using macro morphological characters. Trait selection, data collection, and assignment Six traits were defined for each organism in the data: observed thermal range, maximum height, shape, calcification, energy source, and original individual organism – the first free living life stage of the organism (Table 1; Table S1). These traits were selected to represent a suite of ecological functions that epibenthic organisms provide on reefs, including primary and secondary production, habitat provisioning, reef accretion, growth and reproduction, and the aggregation and release of nutrients (Table 1). Trait data for each organism were assigned using a combination of published sources (e.g. Schneider and Searles 1991) and in-situ observations. Continuous trait data were binned where necessary to account for intra-specific variation (Table 1). For example, while a mean value for the maximum height of each organism would be ideal, in-situ or ex-situ measurements of many individuals of each organism were impractical. Therefore, each species was assigned to a binned range of values (e.g. 500-1000mm). These assigned trait values were then used to assess the trait community structure in analyses. Statistical analyses Previous work by Lacroce et. al (2018, 2020) described abundant macroalgae in 2016 which declined and did not return in 2017 (Fig. 2). To compare a community with abundant macroalgae and one without, the community data was subsetted to June-August of 2016 and June-August 2017 to compare the summer community in each year (Fig. 2). Before anlaysis, community data were arcsin( √ ) transformed to down-weight abundant taxa that are typically over sampled, and to increase the weighting of less abundant taxa that are typically under sampled (Clarke et al. 2014). The arcsin( √ ) transformation is analogous to a ln() transformation but more appropriate for proportional data like percent cover (Sokal and Rohlf 1995). Organisms’ abundances were then combined with their trait values to generate community-weighted means (CWMs) of traits in each observation. For continuous traits, CWMs are the cover-weighted average trait value and for categorical traits CWMs are the proportion of cover made up of each trait modality. These CWMs were used as the trait community matrix. Using a principal component analysis (PCoA) on a Gower dissimilarity matrix of species traits, trait structure of taxa were compared in multidimensional space. By doing so, taxa that are functionally similar to one another are plotted close together, and taxa that are functionally distinct are plotted further apart, with their positions in space corresponding to their overall trait compositions. The plotted trait space was then compared between 2016 and 2017 and overlaid with 2D kernel densities to illustrate the distribution of species’ abundances in trait space (Fig. 3). To compare structuring of the communities in 2016 and 2017, a PCoA was applied to a Bray-Curtis distance matrix generated from the species abundance (i.e. transformed percent cover) matrix while a multi-factor analysis (MFA) was used on the trait community matrix (Bécue-Bertaut and Pagès 2008). MFA is used for trait ordination because it can give equal weighting to unequal groups. The resulting ordinations were then plotted to compare community trends in the two years (Fig. 4). Based on results of this ordination analysis, we specifically examined changes in total algal and invertebrate abundances to illustrate major changes in community structure (Fig. 5B). We next assessed whether changes in trait structure corresponded to changes in biodiversity by comparing both taxonomic and trait diversity between time periods (Fig. 5A). Taxonomic diversity was calculated as Shannon-Weiner diversity of the transformed community data and the ‘dbFD’ distance based functional diversity function from the R package FD was used to calculate Rao’s Quadratic Entropy, an analogous measure of functional diversity (Botta‐Dukát 2005). These calculations and all previous analyses described were performed using R version 4.4.1 (R Core Team 2024). RESULTS Epibenthic reef communities in the summer of 2016 and summer of 2017 were distinct both in taxonomic and trait community structure. In 2016, reef communities were characterized by abundant brown macroalgae Sargassum filipendula , Dictyota spp. , and Dictyopteris hoytii , while the summer of 2017 had consistently low algal abundances (Figs. 2, 5). However, there were similar invertebrate abundances between years (Figs. 4, 5). While this taxonomic change has already been well described (LaCroce et al. 2020), we demonstrate important changes in the trait structure of these communities (Figs. 3, 4). With the loss of macroalgae, communities shifted from tall, structurally complex, uncalcified primary producers to shorter, simpler, calcified consumers (Fig. 4). Since we selected traits to reflect reef functions (Table 1), we accept this shift as evidence that the communities with and without major macroalgal taxa may be functionally distinct from one another. This shift in trait structure is clearly visible in the plotted trait space (Fig. 3). There was a clear shift in the abundance of functional traits provided by tall, fleshy macroalgae in 2016, to less abundant functional traits provided by invertebrates and compressed macroalgae in 2017. This indicates that in addition to the two years being functionally distinct, the loss of macroalgae may have resulted in an overall loss of reef function. Interestingly, despite the major shift in taxonomic and trait structure, there was no visible change in taxonomic diversity (Shannon-Weiner) between years. However, trait diversity (Rao’s quadratic entropy) appeared higher in 2016 compared to 2017 (Fig. 5A). DISCUSSION Here we used species’traits as proxies for reef function to demonstrate that the loss of macroalgae on a temperate reef may have led to a loss of the critical reef functions provided by those species; primarily habitat complexity and primary production. The large, foliose macroalgae which were abundant in the summer of 2016 ( S. filipendula , Dictyota spp. , and D. hoytii ) were much reduced in the summer of 2017, though invertebrates and calcified algae were relatively unchanged (Fig. 2). Interestingly, despite this loss of macroalgal cover there was no major change in taxonomic diversity, and there was a slight increase in functional diversity (Rao entropy) (Fig. 5). Compared to invertebrate taxa, the major macroalgae carry similar traits and may be more functionally redundant to one another. In other words, the three most abundant macroalgal taxa S. filipendula , Dictyota spp. , and D. hoytii all filled a similar functional role. With these species reduced, the total trait community structure shifted from one where CWMs were dominated by trait values represented by these abundant macroalgae, to a distinctly different trait community structure where CWMs were dominated by those represented by invertebrates (Figs. 3, 4). It is possible that substantial cover of any one species of macroalgae could have maintained some of the functional traits, and by extension, reef functions, that this group provided. Despite the loss of these dominant algal taxa and a potentially profound shift in the functional roles they support, there was no visible change in species diversity and only minor change in functional diversity (Fig. 5). This appears to contradict conventional thinking on the relationship between diversity and function, which suggests that ecosystem functioning and biodiversity are tightly linked, and instead supports the notion that trait composition, not diversity, may be more important for understanding ecosystems and their functioning (Rahman et al. 2024). Traits and environmental conditions Some traits in our data can be considered response traits – that is pertaining to an organisms response to environmental or other stressors (Lavorel and Garnier 2002, Hadj-Hammou et al. 2021). Species’ response traits and resulting community trait structure then may correlate with environmental factors and resistance to unfavorable conditions and disturbance. Observed thermal limits, for example, are directly related to a species ability to survive and function in a given environment. In this case, there was little apparent environmental filtering due to thermal limits, since temperatures were consistent during the 2016 and 2017 periods included in this study (see LaCroce 2020 Fig. S1). Along with temperature, light is an important factor for macroalgal growth and reproduction (Peckol 1983, Lapointe and Duke 1984). The tall, structural macroalgae Sargassum filipendula is seasonally abundant on North Carolina hard bottom reefs and had the highest percent cover of epibenthic organisms at the 5-mile ledge study site during the 2016 summer (Fig. 2; LaCroce et al. 2020). It is one of the few North Carolina species for which light requirements for growth are known (Dawes 1987), and bottom light levels were below the photosynthetic compensation point for a majority of the 2017 summer (LaCroce et al. unpublished; Fig. S1). While tall, fleshy macroalgae might provide good biogenic habitat structure and be better competitors for light, they may be more vulnerable to mechanical disturbances such as the wave action from northeasters and hurricanes. This is especially true when thallus strength may be compromised during periods of non-optimal light and temperature conditions. So while the community shifted to shorter, more calcified organisms when foliose macroalgae were lost, that shift may have been in part due to the vulnerability of tall, uncalcified organisms to specific conditions. Epibenthic organisms and reef function on a global scale Lower macroalgal cover logically leads to a loss of trait abundance, and by extension, functions provided by macroalgae. Despite this apparent reduction in competition, slower-growing invertebrate taxa did not increase in the absence of macroalgae, and no functionally similar species were able to fill the functional niche macroalgae left. This phase-shift between macroalgae and invertebrates in North Carolina communities is apparently common and reversible and has been described in previous publications (e.g. Peckol 1982). With many benthic ecosystems in decline globally, such algal-invertebrate phase-shifts may become more prevalent as temperate reefs lose macroalgal cover and coral reefs are increasingly overgrown by macroalgae (Rogers-Bennett and Catton 2019, Gorman et al. 2020, Bosch et al. 2022). As epibenthic reef communities change, so too will the suite of functions they provide. A key example is a loss or alteration of biogenic structure provided by these organisms. Diverse and abundant reef fish communities are correlated with complex reef habitat (Gratwicke and Speight 2005, Darling et al. 2017). In coral reefs, branching corals may provide the primary habitat, but in temperate reefs macroalgae are often the primary source of biogenic habitat (Srednick and Steele 2022). To date it has been difficult to fully separate the importance of physical structure from the other important functions epibenthic organisms may provide. Our analysis demonstrates the feasibility of an epibenthic trait analysis, and emphasizes the utility of incorporating structural measurements as a part of a larger trait set to disentangle biota from structure. Epibenthic organisms trophic mode and trophic level (primary producers, consumers) can further structure fish and mobile invertebrate communities via the storage and cycling of nutrients on reefs (de Goeij et al. 2013, McMurray et al. 2018). Macroalgae often acts as a sink for rapid nutrient pulses, with their ability to absorb nutrients being directly linked to their morphologies (Peckol and Ramus 1988). Macroalgal nutrient uptake initially slows the impact of a nutrient pulse on reef ecosystems, but as macroalgae release DOC, die, reproduce, or are grazed upon, their nutrients are converted to other bioavalable forms of DOM and POM (Krumhansl and Scheibling 2012, Allgeier et al. 2014, Weigel and Pfister 2021). Then, microbes in the water and primary consumers like sponges, gorgonians, and scleractinian corals are able to collect and store those nutrients at a slower rate. Without macroalgae, nutrients may be available to fuel plankton blooms, providing a sudden increase in food for plankton consumers but disadvantaging consumers relying on light due to increased turbidity, ultimately influencing the flow of source carbon and nutrients in the food web (Miller and Hay 1996, Morgan et al. 2020). We illustrate this potential function of nutrient mediation to demonstrate how an ecologist analyzing a reef community could use an appropriate trait analysis that incorporates both energy source and structural complexity to model the relative influence of each of these functional traits on a reef. Future directions Clearly, most macroalgae are distinct from most sessile invertebrates and they likely contribute very differently to reef function. Moreover, tall macroalgae are clearly more vulnerable to wave action disturbance than shorter organisms and organisms with low thermal tolerances cannot survive under high temperature conditions. So, while we demonstrate some overlap in individual traits between algae and invertebrates, our goal is not to state novel relationships between trait community structure and the environment or to conclude that algae and invertebrates are the same, but to demonstrate the utility of quantifying these traits for individual organisms across all epibenthic taxa. That said, there are several areas in which these data and analyses can be improved for future work. The set of trait data we use here is imperfect, with some measurements limited to what was observed in a limited time (e.g. Observed thermal limits) and others broad generalizations (e.g. Shape as Elongate or Filamentous ). There is much work to be done honing this trait data for taxa in other systems, but we suggest our trait data set as a starting framework on which to improve. By improving upon this cross-taxa functional trait set and selecting relevent traits for their questions, ecologists can improve the accuracy and meaningfulness of these and future analyses (see Table S1 for all current trait data). One suggested improvement to the current trait data is collecting morphometric traits for all taxa. This has already been shown to be a useful approach for fish trait analysis and would provide new avenues for analyzing species differences (Su et al. 2018). However, as macroalgae and invertebrates do not share the same organs (e.g. polyps vs blades) measurements for specific organs would not be appropriate. We suggest instead using structure from motion techonology to construct digital 3D models of individual organisms that can be measured for volume, surface area (House et al. 2018), various structural complexity metrics (Guendulain-García et al. 2023), and morphological ratios such as maximum height : maximum width. The collection of these data could be paired with other measurements such as hardness or density of an organism, dry mass of inorganic calcium carbonate, C:N ratios, presence of chemical compounds, and more. Collecting morphological data on individuals would also help improve another weakness of the current data, the lack of intraspecific variability. As suggested, part of the value of epibenthic trait analysis is the potential to better understand how epibenthic community structure influences fish community structure. Therefore, combining reef fish community and trait data with comprehensive epibenthic community and trait data will certainly help reef ecologists to clarify how total reef function may be changing under current climate change scenarios, or predict how management action will impact an ecosystem. We suggest this as a primary application of comprehensive epibenthic trait analysis, as reef fish trait ecology has already grown dramatically in recent years and would be well complemented by this method. Despite the pressing need to understand the impact of changing epibenthic communities on reef function, such as how tall structural macroalgae may supplement the habitat value of degraded coral reefs, inclusive epibenthic trait analysis has not been conducted to our knowledge. Here we have demonstrated how inclusive trait analysis can produce quantitative results linking organisms and communities to reef functioning by showing how two communities with and without major macroalgae are functionally distinct. As algal-invertebrate phase shifts become more prevalent with ocean warming and increased heating events, it will not be enough to separately quantify coral, invertebrate, or algal communities. 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FIGURES TABLES Trait Trait values Analog to function Observed thermal limits Continuous Growth, survival, and reproduction Max height Binned continuous values: Habitat provisioning and growth 0-10 mm 10-100 mm 100-500 mm 500-1000 mm Shape Filamentous Habitat provisioning and growth Elongate Globulose Encrusting Calcification Rigid Defense, habitat provisioning, and reef accretion Flexible Soft Uncalcified Energy source Active consumer Nutrient accumulation, primary/secondary production, and growth Active consumer with symbionts Passive consumer Photosynthetic Original individual organism Planula larvae Settlement dynamics, reproduction, and dispersal Simple motle larvae Tadpole larvae Carposporophyte generated sporophyte or 1N nonmotile spore Flagellated 1N spore Information & Authors Information Version history V1 Version 1 12 March 2025 Peer review timeline Published Marine Ecology Progress Series Version of Record 11 Feb 2026 Published Copyright This work is licensed under a Non Exclusive No Reuse License. Keywords algae community ecology epibenthic functional traits macroinvertebrates trait ecology Authors Affiliations Jared Oviatt 0009-0006-3521-4473 [email protected] University of North Carolina Wilmington View all articles by this author Matthew McLean University of North Carolina Wilmington View all articles by this author Melissa LaCroce North Carolina State University at Raleigh View all articles by this author D Freshwater University of North Carolina Wilmington Center for Marine Science View all articles by this author Metrics & Citations Metrics Article Usage 202 views 307 downloads .FvxKWukQNSOunydq8rnd { width: 100px; } Citations Download citation Jared Oviatt, Matthew McLean, Melissa LaCroce, et al. Epibenthic species traits demonstrate how macroalgal decline degrades temperate reef function. Authorea . 12 March 2025. 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