Coastal Marine Habitats Research Articles

Seasonal dynamics of a glycan-degrading flavobacterial genus in a tidally mixed coastal temperate habitat.

Coastal marine habitats constitute hotspots of primary productivity. In temperate regions, this is due both to massive phytoplankton blooms and dense colonisation by macroalgae that mostly store carbon as glycans, contributing substantially to local and global carbon sequestration. Because they control carbon and energy fluxes, algae-degrading microorganisms are crucial for coastal ecosystem functions. Environmental surveys revealed consistent seasonal dynamics of alga-associated bacterial assemblages, yet resolving what factors regulate the in situ abundance, growth rate and ecological functions of individual taxa remains a challenge. Here, we specifically investigated the seasonal dynamics of abundance and activity for a well-known alga-degrading marine flavobacterial genus in a tidally mixed coastal habitat of the Western English Channel. We show that members of the genus Zobellia are a stable, low-abundance component of healthy macroalgal microbiota and can also colonise particles in the water column. This genus undergoes recurring seasonal variations with higher abundances in winter, significantly associated to biotic and abiotic variables. Zobellia can become a dominant part of bacterial communities on decaying macroalgae, showing a strong activity and high estimated in situ growth rates. These results provide insights into the seasonal dynamics and environmental constraints driving natural populations of alga-degrading bacteria that influence coastal carbon cycling.

Morphology and phylogeny of four trachelocercid ciliates (Ciliophora, Karyorelictea, Trachelocercidae) from North China Sea, with description of a new species

Trachelocercids are common ciliates in marine sandy intertidal zones, however, only few species have been described using modern taxonomic techniques, with several earlier descriptions still lacking primary data, such as a detailed description of the oral ciliature. For this reason, systematics of the family Trachelocercidae Kent, 1881 resulted in paraphyletic genera and needs a critical revision. As an attempt to fill the gap of knowledge for this group, this study presents one new species description, Tracheloraphis apodiscolor n. sp., along with redescriptions of three lesser-known trachelocercid species, Trachelocerca bodiani (Dragesco, 1963) Dragesco, 2002, Trachelocerca ditis (Wright, 1982) Foissner & Dragesco, 1996 and Prototrachelocerca fasciolata (Sauerbrey, 1928) Foissner, 1996, collected from coastal marine habitats at Qingdao (China), using live and protargol-stained specimens. Tracheloraphis apodiscolor n. sp. can be distinguished from its closest related congener, T. discolor, by a shorter body length and fewer somatic kineties. Molecular data of T. apodiscolor n. sp. and T. bodiani were provided for the first time. Additionally, based on the Qingdao populations, we provide improved diagnoses for T. ditis and P. fasciolata. Phylogenetic analyses were performed and discussed, as there is strong support for paraphyly of the genera Tracheloraphis and Trachelocerca. In general, more integrative studies based on taxonomy, ultrastructure as well as molecular data are needed to properly shed light on the systematics of trachelocercids.

Algal bloom ties: Systemic biogeochemical stress and Chlorophyll-a shift forecasting

Algae are deemed to be the highest carbon drawdown contributors in the world. Almost half of the world’s organic carbon is fixed by marine phytoplankton, especially during algal blooms, despite accounting for less than one percent of the total photosynthetic biomass on Earth. Nonetheless, there are growing concerns about the rise of harmful algal blooms in terms of their persistence and distribution that is a fingerprint of both global climate and local anthropogenic pressure.A novel forecasting model – combining transfer entropy network inference and a forecasting convolution neural-network – is used to predict bloom and non-bloom epidemic regimes, and their environmental determinants to define bloom sources, causes and systemic risk. The model shows high forecasting skills by extracting salient ecosystem features even without spatial dependencies. We defined a 2D entropic ecosystem mandala where the ecological impact, manifested by the distribution’s randomness of Cyanobacteria-driven chlorophyll-a (CHL-a), is proportional to the systemic environmental pressure/stress determined by a set of erratic ocean/climate and coastal/nutrient factors. Originally, a spatial risk was defined based on CHL-a magnitude, persistence and shifts. Considering the temporal variability of CHL-a in Florida Bay (FL Bay) as a case-study, we show how shifts in algal blooms are becoming more persistent in shallow areas with higher dinoflagellate/diatom ratio. This emphasizes the likely key role of cyanobacteria disorganization into phytoplankton organization, and thus the role of land discharge into the marine microbiome balance. This presents major challenges considering the increasing potential causality of green–blue algal blooms (river-dominated) for harmful red-tides with cascading socio-ecological effects, including carbon cycling alteration and ingrained eutrophication in coastal ecosystems. A universal threshold on the top 20% Pareto CHL-a extremes clearly defines bloom and non-bloom regimes independently of being endemic or epidemic, underpinned by distinct eco-environmental interactions, where the largest biogeochemical stress is structurally scale-free with CHL-a as the hub.Forecasting algal bloom in short- and long-term is indispensable for quantifying ecosystem health considering coastal-marine habitats, species and humans, as well as impacts into environmental processes such as carbon sequestration capacity. However, the increasing disorganization of biogeochemical stress decreases our forecasting ability of algal blooms except during outbreaks when is too late for prevention. This has impacts for investigating and controlling eco-environmental determinants of undesired algal bloom emergence and spread.

ANALYSES OF THE AVIFAUNA AND BIRD POPULATIONS OF THE ISLAND OF ITURUP, GREAT KURIL ISLANDS

Ecological patterns in the formation of the avifauna and bird populations of the Iturup Island were analyzed. Route counts were used along transects of unlimited width. As many as 116 bird species were registered, including 36% revealed to be ubiquitous, another 34% local and further 26% highly local. 71 species were shown to nest. The taxonomic structure of the avifauna, represented by species from 15 orders, corresponded to the zonal and landscape features of the island’s territories located at the eastern margins of northern Eurasia. Passeriformes (37%), Charadriiformes (22%), Anseriformes (9%), Procellariiformes (8%) prevailed. The zoogeographic peculiarity of the local avifauna was a combination of elements of the Far Eastern island, Pacific, Siberian and Chinese faunistic complexes, some Siberian-American and widespread species, as well as Japanese island endemics. The avifauna around the Iturup Island, formed by a system of general zonal-landscape and altitudinal-belt patterns, united ecological groups of marine and land species, including montane ones (n = 9). Local avifauna in coastal marine habitats included 41 species, vs 55 in forests, 37 in light forests, and 46 in tall grasses, the population density being 607, 785, 968, 518 individuals/km2, respectively. The similarity coefficients for the populations of forest habitats were 19–48%, vs 22% for light forests, 20–37% for tall grasses, while in the sea coast and adjacent water areas they amounted to 21–52%. The populations of terrestrial habitats were dominated by the Oriental Turtle-dove, the Pacific Swift, the Siberian Rubythroat, the Japanese Bush-warbler, the Marsh Tit, the Coal Tit, the Eurasian Nutcracker, the Oriental Greenfinch, the Eurasian Siskin, the Long-tailed Rosefinch, the Masked Bunting, and the Grey Bunting. The populations of the coast and adjacent sea area were dominated by the Japanese Cormorant, the Rufous-necked Stint, the Slaty-backed Gull, the Black-tailed Gull, and the Black-backed Wagtail. In open sea areas, the most common were the White-winged Scoter, the Black-footed and Laysan albatrosses, the Northern Fulmar, and the Short-tailed Shearwater.

The development of decontamination methods in coastal marine habitats by transplantation of the mussel Mytilus galloprovincialis (Lamarck, 1819): Comparison between in vivo and in situ investigations

The health status of Mytilus galloprovincialis native from a polluted habitat was surveyed before and after 30 and 60 days of in situ transplantation and in vivo experiments. The results showed a reduction in filtration rate by 24 % and 45 %, respectively, after 60 days of in vivo and in situ experiments compared to the rates at polluted sites. The respiration rate reached a minimum of 0.081 ± 0.05 mg O2.L−1 after 60 days of in situ transplantation. Moreover, the antioxidant activities were changed in a time-dependent manner for both transplantation conditions. The highest superoxide dismutase and catalase activities corresponded to the stressed mussels and declined by 76 % and 54 %, respectively, after 60 days of in situ transplantation. Changes in lipid peroxidation and acetylcholinesterase activity were observed in internal organs following 60 days of transplantation. At this time slot, the lowest content of metals and microplastics was also noticed.

How environmental beliefs influence the acceptance of reallocating government budgets to improving coastal water quality: a hybrid choice model

ABSTRACT In this study, we analyse how beliefs concerning environmental action influence choices in a stated preference survey on coastal water quality and marine habitat areas. Survey respondents were presented with a series of choice tasks featuring improvements in water clarity, reef health, seagrass area and a series of costs in the form of reallocated state budget against a baseline of no new improvements and no change in the budget. The reallocated budget scenario was used as it is likely to be realistic to respondents. Estimates of willingness to reallocate were obtained using a hybrid choice model which included the choice data, attitudinal data regarding support for environmental action and sociodemographic characteristics. Our results suggest that beliefs supporting environmental action influence the willingness to reallocate for attributes that change coastal water quality. A decision support tool for policy analysts was developed to illustrate how public support, as a probability of supporting reallocation, is shaped by beliefs and changes with sociodemographic characteristics.

Hyposalinity reduces coordination and adhesion of sea urchin tube feet.

Climate change will increase the frequency and intensity of low-salinity (hyposalinity) events in coastal marine habitats. Sea urchins are dominant herbivores in these habitats and are generally intolerant of salinity fluctuations. Their adhesive tube feet are essential for survival, effecting secure attachment and locomotion in high wave energy habitats, yet little is known about how hyposalinity impacts their function. We exposed green sea urchins (Strongylocentrotus droebachiensis) to salinities ranging from ambient (32‰) to severe (14‰) and assessed tube feet coordination (righting response, locomotion) and adhesion [disc tenacity (force per unit area)]. Righting response, locomotion and disc tenacity decreased in response to hyposalinity. Severe reductions in coordinated tube foot activities occurred at higher salinities than those that affected adhesion. The results of this study suggest moderate hyposalinities (24-28‰) have little effect on S. droebachiensis dislodgement risk and survival post-dislodgment, while severe hyposalinity (below 24‰) likely reduces movement and prevents recovery from dislodgment.

Light pollution alters the skeletal morphology of coral juveniles and impairs their light capture capacity

Urbanization and infrastructure development have changed the night-time light regime of many coastal marine habitats. Consequently, Artificial Light at Night (ALAN) is becoming a global ecological concern, particularly in nearshore coral reef ecosystems. However, the effects of ALAN on coral architecture and their optical properties are unexplored. Here, we conducted a long-term ex situ experiment (30 months from settlement) on juvenile Stylophora pistillata corals grown under ALAN conditions using light-emitting diodes (LEDs) and fluorescent lamps, mimicking light-polluted habitats. We found that corals exposed to ALAN exhibited altered skeletal morphology that subsequently resulted in reduced light capture capacity, while also gaining better structural and optical modifications to increased light levels than their ambient-light counterparts. Additionally, light-polluted corals developed a more porous skeleton compared to the control corals. We suggest that ALAN induces light stress in corals, leading to a decrease in the solar energy available for photosynthesis during daytime illumination.

Physiological condition of the warty venus (Venus verrucosa L. 1758) larvae modulates response to pile driving and drilling underwater sounds

Noise is now recognized as a new form of pollution in marine coastal habitats. The development of marine renewable energies has introduced new sonorous perturbations, as the wind farm installation requires pile driving and drilling operations producing low frequency sounds at high sound pressure levels. Exponential expansion of offshore wind farms is occurring worldwide, making impact studies, particularly on benthic species highly abundant and diverse in the coastal area used for wind farming, a necessity. As larval recruitment is the basis for establishing a population, we conducted an experimental study to assess the interactive effects of pile driving or drilling sounds and larval rearing temperature on the endobenthic bivalve Venus verrucosa. In ectothermic animals, temperature modifies the organism’s physiology, resulting in performance variability. We hypothesize that temperature modulation could change larval responses to noise and explore the potential interacting effects of temperature and noise. Using two distinct rearing temperatures, physiologically different batches of larvae were produced with contrasting fatty acid content and composition in the neutral and polar lipid fractions. Without defining any absolute audition threshold for the larvae, we demonstrate that the effects of temperature and noise were ontogenic-dependent and modulated larval performance at the peri-metamorphic stage, acting on the metamorphosis dynamic. At the pediveligers stage, a strong interaction between both factors indicated that the response to noise was highly related to the physiological condition of the larvae. Finally, we suggest that underwater noise reduces the compensatory mechanisms established to balance the temperature increase.

New species, new records and key to the species of the Rhagoveliaitatiaiana group (Hemiptera, Heteroptera, Veliidae) from Brazil.

Rhagovelia Mayr, 1865 (Hemiptera, Heteroptera, Veliidae), known as riffle bugs, includes more than 400 species and is commonly found in tropical lotic environments, including coastal marine habitats, such as mangroves and estuaries. Due to the elevated number of species, the fauna from the Americas has been divided into several groups, which facilitates taxonomic studies. Amongst them, the itatiana group currently includes two species from the Greater Antilles and five from south-eastern and southern Brazil. Despite the many taxonomic studies developed during the past few decades, new species of Rhagovelia are still being discovered in several areas of the continent, including the Atlantic Forest of eastern Brazil. Rhagoveliabispoi sp. n. is described, illustrated and compared with similar congeners. The new species belongs to the itatiaiana group and can be diagnosed by the uniformly black mesonotum, the presence of a tuft of setae medially on male abdominal sternum VII, the armature of the male hind femur and the distinctive shape of the paramere. In addition, we present new records of R.trepida Bacon, 1948 from the States of Paraná and Santa Catarina and a key to the species of the itatiaiana group recorded from Brazil.

Cenozoic colonisation of the Indian Ocean region by the Australian freshwater-originating glassperch family Ambassidae (Teleostei)

We examined the phylogeny and biogeography of the glassperch family Ambassidae (Teleostei), which is widely distributed in the freshwater, brackish and marine coastal habitats across the Indo-West Pacific region. We first built a comprehensive time-calibrated phylogeny of Ambassidae using five genes. We then used this tree to reconstruct the evolution of the salinity preference and ancestral areas. Our results indicate that the two largest genera of Ambassidae, Ambassis and Parambassis, are each not monophyletic. The most recent common ancestor of Ambassidae was freshwater adapted and lived in Australia about 56 million years ago. Three independent freshwater-to-marine transitions are inferred, but no marine-to-freshwater ones. To explain the distribution of ambassids, we hypothesise two long-distance marine dispersal events from Australia. A first event was towards Southeast Asia during the early Cenozoic, followed by a second one towards Africa during mid-Cenozoic. The phylogenetic signal associated with the salinity adaptation of these events was not detected, possibly because of the selective extinction of intermediate marine lineages. The Ambassidae shares two characteristics with other freshwater fish groups distributed in continental regions surrounding the Indian Ocean: They are too young to support the hypothesis that their distribution is the result of the fragmentation of Gondwana, but they did not retain the phylogenetic signal of their marine dispersal.

Thallium toxicity to temperate and tropical marine organisms: Derivation of water quality guidelines to protect marine life

A lack of thallium (Tl) toxicity data for marine organisms has hampered the development of water quality guidelines for protecting marine life and assessing ecological hazard/risk. This study assessed the toxicity (EC10/EC50) of Tl in natural seawater (salinity 34 psu and pH 8.05) to 26 functionally diverse marine organisms (19 phyla from five trophic levels) from a variety of temperate and tropical coastal marine habitats. EC10 values ranged from 3.0 μg/L (copepod, Acartia tranteri) to 489 μg/L (cyanobacterium, Cyanobium sp.), while EC50 values ranged from 9.7 μg/L to 1550 μg/L. Thallium(I) was the dominant (86–99 %) oxidation state in test waters across the range of EC10 and EC50 values. Thallium toxicity (EC10/EC50) did not differ between temperate and tropical marine organisms. New, reliable, long-term Tl water quality guidelines were derived using species sensitivity distributions (with model-averaging) to protect marine life in Australia (e.g., 3.9 μg/L for 95 % species protection).

Assessment of natural capital and environmental flows distribution: A Mediterranean case study

The coastal marine area hosts among the most productive ecosystems in the world, in terms of biomass and species richness. These ecosystems’ natural capital stocks provide essential flows of resources for the environment and human life. The distribution of natural capital (NC) and environmental flows (ENFL) characterizing the coastal marine habitats of Ligurian Sea, a biodiversity hotspot in the Mediterranean region, were assessed to define their current state. The study area was divided into 43 functional spatial sections, defined as “biomarine units”. In each biomarine unit natural capital and environmental flows were estimated using data on benthic and fish biomass. Emergy analysis, a thermodynamics-based methodology that expresses the costs in terms of resources incurred by nature to maintain the ecological processes of the marine coastal habitats, was then applied to assess the natural capital and the environmental flows in biophysical terms (solar emergy joules, sej), and using appropriate conversion factors, in monetary terms (emergy euro, em€). The monetary equivalents facilitate understanding for stakeholders and pave the way for the inclusion of marine resources value in socioeconomic and political contexts. The total value of natural capital for the Ligurian coastal and marine area is 2.11 billion em€, while for environmental flows, it is 1.43 billion em€ a−1. Greater values belong to units included within the boundaries of protected areas, proving the efficiency of the protection measures taken. These values represent a reference point and shall be kept constant to preserve natural capital and to ensure services provisioning at least at the current level. This work identify a method useful to monitor the status of natural capital value and environmental flows along Ligurian coast, which can be helpful to stakeholders and policymakers for better monitoring and management of the area.

Baseline Assessment of Ecological Quality Index (EQI) of the Marine Coastal Habitats of Tonga Archipelago: Application for Management of Remote Regions in the Pacific

The loss of coral habitats and associated biodiversity have direct effects both on the physical dynamics of the coast and on natural resources, threatening the survival of local populations. Conservative actions, such as the creation of new Marine Protected Areas, are urgent measures needed to face climate change. Managers need fast and simple methods to evaluate marine habitats for planning conservation areas. Here, we present the application of an Ecological Quality Index (EQI), developed for regional-scale habitat maps of the Atlas of the Marine Coastal Habitats of the Kingdom of Tonga, by processing Copernicus Sentinel-2 imagery. Both the habitat mapping classification and the EQI application were focused on the importance of coral reef, seagrass and mangrove habitats, both as natural defense and sustenance for the local populations. Twelve main Pacific reef habitats were evaluated through a three-level EQI score assigned to six parameters: nursery ground, connectivity, species reservoir, fish attraction, biodiversity and primary production. The EQI was integrated into a developed georeferenced database associated to the QGIS software providing the ability to identify on the maps the area of interest and the associated habitats, and to quantify their ecological relevance. The EQI is proposed as a tool that can offer to stakeholders and environmental managers a simple and direct indicator of the value of the marine coastal environment. The index may be handled for management purposes of vast areas with remote and uninhabited islands.

Synbiotics and aquamimicry as alternative microbial-based approaches in intensive shrimp farming and biofloc: Novel disruptive techniques or complementary management tools? A scientific-based overview

Globally, aquaculture, especially shrimp farming, plays an important economic role. However, it is known that traditional shrimp farming could negatively create environment impacts (e.g. due to water discharge into coastal areas and marine habitats), if good management practices are not followed. For these problems to be minimized, the industry needs to develop and implement technologies that promote sustainable aquaculture. Among different techniques, the biofloc technology (BFT) system and, more recently, the synbiotics and aquamimicry are considered alternatives microbial-based approaches that address high yields with certain level of biosecurity and better environmental practices. However, different from biofloc, both aquamimicry and synbiotics use fermented carbon sources in their routine practices. The present article aims to bring (i) the current status and research and development (R&D) efforts, (ii) the basics principles around synbiotics and aquamimicry; (iii) compares their key characteristics and (iv) discuss whether these two systems would be considered novel disruptive techniques or more likely management tools. The manuscript evidenced both systems share several operational and microbial similarities, and operate under comparable conditions. Recent bibliometric analysis (Web of Science) showed 578 articles for BFT, and only 20 for synbiotics and 3 for aquamimicry, an evident lack of scientific background highlighting that more science-based R&D efforts are needed in synbiotics and aquamimicry.

Evaluating Connectivity of Coastal Marine Habitats in the Gulf of Maine by Integrating Passive Acoustics and Metabarcoding

Ecological connectivity among coastal marine habitats—linkage in the movement of organisms and natural processes across habitat boundaries—has significant implications for the health and resilience of commercially important or threatened species in the Gulf of Maine (GOM), off the coast of the northeastern United States. Methods designed to efficiently assess connectivity are vital for identifying and managing critical habitats (Perry et al., 2018). Paired use of passive acoustic monitoring (PAM) and metabarcoding seawater samples (MSS) for observing biological and functional connectivity at various spatiotemporal scales in the marine environment is largely unexplored and may provide an efficient alternative or supplement to existing strategies.

Characterization of Redox Sensitive Brown Algal Mannitol-1-Phosphatases

Macroalgae (seaweeds) are key primary producers in marine coastal habitats and largely contribute to global ocean carbon fluxes. They also represent attractive renewable feedstock for the production of biofuels, food, feed, and bioactive. Brown algae are seaweeds that produce alginates and fucose containing sulfated polysaccharides in their cell wall and laminarin and mannitol for carbon storage. The availability of genomes of the kelp Saccharina japonica and of the filamentous Ectocarpus sp. paved the way for the biochemical characterization of recombinant enzymes involved in their polysaccharide and carbohydrates synthesis, including, notably, mannitol. Brown algal mannitol biosynthesis starts with the conversion of fructose-6-phospate into mannitol-1-phosphate (mannitol-1P), and this intermediate is hydrolysed by a haloacid dehalogenase phosphatase (M1Pase) to produce mannitol. We report here the biochemical characterization of a second M1Pase in Ectocarpus sp. (EsM1Pase1). Both Ectocarpus M1Pases were redox-sensitive enzymes, with EsM1Pase1 active only in presence of the reducing agent. Such catalytic properties have not been observed for any M1Pases yet. EsM1Pases were specific to mannitol-1-P, in contrast to S. japonica M1Pases that could act on other phosphorylated sugars. Finally, brown algal M1Pases formed two well-supported clades, with possible distinct subcellular localization and physiological role(s) under diverse environmental conditions and/or life cycle stages.

Effects of COVID-19 lockdown on the observed density of coral reef fish along coastal habitats of Moorea, French Polynesia.

The online version contains supplementary material available at 10.1007/s10113-022-02011-0.

Structural Diversity, LC-MS-MS Analysis and Potential Biological Activities of Brevibacillus laterosporus Extract.

Lake Mariout is Egypt's degraded coastal marine habitat that encompasses a variety of wastes. The biodiversity and hard environmental conditions allow the co-existence of organisms with high resistance and rich metabolism, making them potential candidates for screening and isolating novel microbial strains. A bacterial isolate (BF202) cultured from the marine sediments of Alexandria's Mariout Lake (Egypt) was tested for its antimicrobial and anticancer potential. The phylogenetic analysis of the isolated strain's 16S rDNA and gyrB revealed that BF202 belongs to Brevibacillus laterosporus (B. laterosporus). Antibiosis of B. laterosporus was confirmed against microbial pathogens including Escherichia coli, Klebsiella pneumoniae, Salmonella typhi, and Staphylococcus aureus. The highest antibacterial activity was detected on glucose peptone medium after 18 h of incubation at 35 °C, and at pH of 7.0 in the presence of mannose and ammonium carbonate as carbon and nitrogen sources, respectively. The cytotoxicity of the methanolic extract against breast cancer (MCF-7) and normal Vero cell lines, using the MTT test, revealed IC50 values of 7.93 and 23.79 µg/mL, respectively. To identify apoptotic and necrotic cells, a flow cytometric analysis using annexin V-FITC/PI dual-labeling was utilized and recorded a higher number of necrotic cells compared to apoptotic ones. Similarly, the cell cycle S-phase arrest was reported. The LC-MS-MS investigation of B. laterosporus extract and the molecular networking database analysis demonstrated five strategic diketopiperazine compounds with antimicrobial and anticancer activities. Taken together, this research shows that the crude extract of B. laterosporus might be an effective agent against drug-resistant bacteria and malignant disorders due to its richness in diketopiperazines.

A quantitative synthesis of approaches, biases, successes, and failures in marine forest restoration, with considerations for future work

Abstract Marine forests is a term commonly used for coastal marine habitats formed by dense stands of brown macroalgae, typically consisting of kelp and fucoids. These habitats are highly productive, offer habitat to numerous marine organisms, and support a range of invaluable ecosystem services. Despite their importance, marine forests are declining in many regions around the world as a result of interacting global, regional, and local‐scale stressors. Consequently, interest in restoration as a tool to mitigate these declines and reinstate marine forests is growing. Recent reviews have provided insights into marine forest restoration; however, for the most part, a synthesis of restoration success is lacking. A meta‐analysis and quantitative review of published marine forest restoration efforts was conducted to examine: (i) how restoration affects the abundance and morphology of marine forest species; and (ii) trends in marine forest restoration success. The meta‐analysis of 25 studies revealed that restoration positively influences the abundance and morphology of marine forest species. The quantitative review of 63 studies demonstrated that taxa and restoration technique were important factors influencing restoration success, and revealed a bias towards the monitoring and reporting of abundance and morphological response variables. The review also highlighted a lack of monitoring and/or reporting of environmental variables at restoration sites, and limited comparative research across environmental contexts and restored species. It is shown that successful marine forest restoration is possible at experimental scales, but that better monitoring and reporting of restoration efforts, alongside increased project durations, could improve our understanding of restoration success at the ecosystem level. Considerations for future marine forest restoration efforts are also provided. It is hoped that the review will advance marine forest restoration efforts, allowing the preservation of these valuable ecosystems and their associated services.