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Christie H, Jorgensen N, Norderhaug K, Waage-Nielsen E.. Species distribution and habitat exploitation of fauna associated with kelp (Laminaria hyperborea) along the Norwegian coast. J Mar Biol Assoc UK 83: 687-699
Abstract and Figures
Fauna associated with the common kelp along the Norwegian coast, Laminaria
hyperborea, was sampled at four sites covering 1000 km of coastline. Exploitation of the kelp habitat by the fauna, and the ways in which habitat size and seasonal variations affect the kelp fauna community were analysed. The study focused on mobile macrofauna, of which 238 species were found on 56 kelps sampled, with an average density of almost 8000 individuals per kelp. Amphipods and gastropods were the most diverse and abundant fauna groups. The species composition was different on the lamina, stipe (with epiphytic algae) and holdfast. A similar pattern of epiphyte- and holdfast-fauna composition was found for all regions. Lowest diversity and abundance were found on the lamina, and highest diversity in the holdfast. Highest abundance was found on the stipe in summer, but there were large variations between sites and seasons, from a few individuals to more than 80 000 animals per stipe. Neither seasonal changes nor variation in habitat volume affected the number of species significantly, but abundance was significantly related to season and habitat volume. These variations were most pronounced for stipe fauna. Laminaria
hyperborea offers a heterogeneous habitat exploited by a diverse and abundant invertebrate community, its abundance depending on local and regional variations in kelp size.
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... The extensive, complex coastline of the northeast Atlantic Ocean supports vast, productive and diverse stipitate kelp forest ecosystems , which represent vital fisheries habitats Jackson-Bué et al. 2023), valuable repositories of biodiversity (Christie et al. 2003;Smale, Epstein, et al. 2020;King et al. 2021;Earp et al. 2024) and important components of coastal carbon and nutrient cycles Pessarrodona et al. 2018;Smale, Pessarrodona, et al. 2020). The widespread kelp L. hyperborea serves as the dominant foundation species along open wave-exposed coastlines, forming dense forests extending from the low intertidal to depths in excess of 30 m in clear waters Smith et al. 2021). ...
Aim
Kelp forests support high biodiversity, primary productivity and ecosystem service value but exhibit high levels of spatiotemporal variability, which can complicate management and conservation efforts. A better understanding of multiscale temporal variability is needed to improve understanding of kelp forest dynamics.
Location
West Scotland and southwest England, United Kingdom.
Methods
We utilised high‐resolution quantitative historical records from the 1940s and 1980s, combined with robust multiyear contemporary field surveys, to explore intra‐ and inter‐decadal scale variability in population structure of the kelp Laminaria hyperborea in two regions of the UK (‘cool’ conditions in west Scotland, versus ‘warm’ conditions in southwest England).
Results
Over decadal timescales, the abundance (i.e., density, standing stock) of a kelp population in southwest England declined, which aligns with a concurrent increase in sea temperatures above the optimum for the performance of this species. Conversely, a population in western Scotland exhibited stability, with plant density and size remaining consistent over multiple decades. Over shorter timescales (across 10 years of contemporary surveys), kelp populations in both regions exhibited minimal temporal variability, in terms of plant density, cover and standing stock, indicating that this species underpins stable and abundant habitat.
Main Conclusions
Compared to many kelp ecosystems globally, and contrary to the widely accepted highly dynamic nature of these habitats, L. hyperborea populations exhibited marked stability across years and (in the case of west Scotland) decades, although gradual ocean warming is likely eroding the resilience of populations in warmer waters located towards this species upper thermal limit. While historical evidence allowed us to reconstruct ecological baselines, patterns must be interpreted with caution as the number of available sites was very limited. Improved monitoring of these vital coastal habitats is needed to better understand patterns and drivers of temporal variability over multiple time scales.
... O espaço intersticial criado entre o substrato rochoso do fundo marinho e os rizóides apterantes oferece proteção à fauna intersticial contra predadores e condições ambientais adversas; além disso, permite a acumulação de fontes de alimento e aumenta a área do substrato e, consequentemente, a área disponível para colonização 15 . A fauna associada aos rizóides de Laminaria é composta por invertebrados móveis, como copépodes harpacticoides, poliquetas, gastrópodes e anfípodes, bem como fauna séssil, como briozoários, bivalves e esponjas 15,16,17,18,19,20,21,22,12 . Além disso, essas algas gigantes, devido ao seu tamanho de vários metros, atuam como engenheiras de ecossistemas, protegendo ambientes costeiros da ação intensa das ondas: elas funcionam como barreiras naturais contra ressacas e outros eventos extremos. ...
As florestas de Laminaria ochroleuca no Estreito de Messina e no Mar de Alborão (Mar Mediterrâneo) são verdadeiras espécies relictas atlânticas, provavelmente remontando ao Plioceno ou a períodos anteriores, que permaneceram isoladas nessas áreas do Mar Mediterrâneo devido à presença de condições químicas e físicas semelhantes às do Oceano Atlântico temperado, de onde se originam. Elas representam um habitat prioritário, ou seja, um habitat natural ao qual a Comunidade Europeia atribuiu prioridade de conservação. Essas florestas gigantes de kelp são espécies resilientes e altamente relacionais, estabelecendo inúmeras relações recíprocas sustentáveis com o ambiente biótico e abiótico e com as populações costeiras nativas do Mediterrâneo, fornecendo diversos serviços ecossistêmicos. As relações recíprocas e interconectadas que caracterizam os serviços ecossistêmicos dessas florestas desencadeiam um efeito dominó (ou efeito borboleta), com consequências positivas para a saúde integral do ecossistema, no qual as populações costeiras nativas estão entre as muitas espécies beneficiárias. O bem-estar de uma espécie reflete intrinsecamente o bem-estar integral de um ecossistema. Portanto, as populações costeiras nativas do Mediterrâneo devem desenvolver uma nova consciência e habilidades relacionais. Os objetivos desta contribuição científica são fornecer considerações e percepções valiosas sobre as interconexões entre os serviços ecossistêmicos das florestas de L. ochroleuca, apresentar dados preliminares e observações sobre as atividades de ciência e pesquisa participativa realizadas por pesquisadores e mergulhadores no Estreito de Messina, bem como abordar a saúde integral do ambiente marinho e das populações nativas mediterrâneas que vivem ao longo dessas costas.
... O espaço intersticial criado entre o substrato rochoso do fundo marinho e os rizóides apterantes oferece proteção à fauna intersticial contra predadores e condições ambientais adversas; além disso, permite a acumulação de fontes de alimento e aumenta a área do substrato e, consequentemente, a área disponível para colonização 15 . A fauna associada aos rizóides de Laminaria é composta por invertebrados móveis, como copépodes harpacticoides, poliquetas, gastrópodes e anfípodes, bem como fauna séssil, como briozoários, bivalves e esponjas 15,16,17,18,19,20,21,22,12 . Além disso, essas algas gigantes, devido ao seu tamanho de vários metros, atuam como engenheiras de ecossistemas, protegendo ambientes costeiros da ação intensa das ondas: elas funcionam como barreiras naturais contra ressacas e outros eventos extremos. ...
The forests of Laminaria ochroleuca in the Strait of Messina and the Alboran Sea (Mediterranean Sea) are true Atlantic relict species, probably dating back to the Pliocene or earlier, that have remained isolated in these areas of the Mediterranean Sea due to the presence of chemical and physical conditions similar to those of the temperate Atlantic Ocean from which they originate. They represent a priority habitat, i.e., a natural habitat to which the European Community has assigned conservation priority. These giant kelp forests are resilient and highly relational species, establishing numerous sustainable reciprocal relationships with the biotic and abiotic environment and with the Mediterranean native coastal populations, providing various ecosystem services. The reciprocal and interconnected relationships characterizing the ecosystem services of these forests trigger a domino effect (or butterfly effect), with positive consequences for the integral health of the ecosystem in which native coastal populations are among the many beneficiary species. The well-being of a species inherently reflects the integral well-being of an ecosystem. Mediterranean native coastal populations therefore should develop a new awareness and relational skills. The objectives of this scientific contribution are to provide valuable considerations and insights on the interconnections between ecosystem services of L. ochroleuca’s forests, preliminary data, and remarks concerning participatory science and research activities carried out by researchers and divers in the Strait of Messina, as well as the integral health of the marine environment and the native Mediterranean populations living along these shores.
... Nevertheless, this will be temporary if the biomass is to be harvested entirely (Christie et al., 2003;Corrigan et al., 2023b). The research suggests that a partial harvest can reduce costs while preserving habitats for these organisms, leading to a higher taxa richness. ...
Offshore wind energy has become an essential substitute in the European energy mix, serving as a renewable energy source for Denmark. The increasing need to decommission oil & gas installations in the North Sea has sparked significant interest in the decommissioning of offshore wind farms (OWF). These installations will inevitably require decommissioning, which is currently under thorough examination by the offshore wind commissioners. Various methods are being considered, from complete removal to leaving the subsea structures in place. Increased awareness of the marine ecosystems developed around these offshore structures has raised concerns about finding the most appropriate decommissioning method. In response to Europe’s growing interest in expanding seaweed cultivation, this study aims to merge these interests by exploring the potential of cultivating kelp on the foundations remaining after the removal of offshore wind installations. This approach will explore the sustainability of this decommissioning option and examine the long-term carbon storage capabilities of two OWFs in Denmark. Additionally, this study will investigate how this decommissioning strategy interacts with the Sustainable Development Goals and the potential carbon quota markets, offering a new and innovative concept for stakeholders considering various decommissioning methods. This thesis will use System Dynamics as a simplified method to quantify the carbon storage potential and provide a comprehensive and interdisciplinary review of offshore wind decommissioning in relation to seaweed’s carbon storage capabilities.
... Kelp forests support a diverse ecosystem and numerous epifauna living on the kelp (Christie et al. 2003), and many fish species use this habitat for feeding and shelter (Norderhaug et al. 2005). However, the role of kelp forests for zooplankton is largely unexplored. ...
Kelp forests are dynamic coastal habitats that generate large amounts of carbon‐rich detritus. The fate of this detritus is largely unknown and considered a missing link in global carbon budgets. Kelp detritus can serve as food for benthic invertebrates and pelagic invertebrate larvae, but we know close to nothing about the role of kelp detritus as food for other zooplankton. We conducted feeding experiments to test if the highly abundant pelagic copepod Calanus finmarchicus can feed on fragments of two dominant kelp species, Saccharina latissima and Laminaria hyperborea . A series of experiments including particle ingestion, fecal pellet production, and DNA tracing tended to support the hypothesis that C. finmarchicus can feed on kelp particles of both species, but at a reduced rate relative to when on a regular phytoplankton diet. Moreover, the results provide initial evidence that L. hyperborea contains substances that are toxic to copepods, an observation that warrants further research. Pelagic copepods consuming kelp detritus would constitute a largely undescribed pathway of carbon from benthic primary producers to the pelagic food web, and a trajectory for deep‐sea carbon sequestration. We hope these preliminary results will inspire future studies on the role of pelagic filter feeders in carbon transport and turnover from macroalgae habitats.
... Fabricia stellaris (Müller, 1774) (Davoult et al., 1999;Christie et al., 2003) with additional reports from the Caribbean Sea and the Mediterranean Sea (Davoult et al., 1999;Miloslavich et al., 2010). There are currently no biogeographic or population genetic studies available for this species. ...
This study presents the first comprehensive annotated checklist of polychaetes collected from floating dock communities across New England and adjacent New York areas, emphasizing the significance of rapid biodiversity assessment surveys in understanding marine biodiversity. With 61% of the identified species classified as cryptogenic, the research highlights the complexity of marine biogeography and the challenges of distinguishing between native and non-native species. The incorporation of DNA barcoding has significantly improved species identification and revealed the presence of cryptic species complexes. The study's findings illustrate the prevalence of tubicolous families (Spionidae, Serpulidae, Sabellidae, and Terebelllidae) that are susceptible to anthropogenic dispersal mechanisms. It also addresses the challenge posed by the high proportion of cryptogenic species, calling for enhanced taxonomic and genetic analyses to resolve their origins and ecological roles. Despite the temporal variation in polychaete composition across years, the absence of distinct community assemblages suggests a level of resilience within floating dock communities. Our study advocates for the continuation and expansion of rapid assessment surveys, coupled with the integration of genetic methodologies, to provide a clearer picture of marine biodiversity.
The relationships between meiofaunal communities and hard substrate are relatively well-documented in the scientific literature. However, a comprehensive quantitative review of global research on meiofauna colonization across different hard substrates has not yet been conducted. In this study, a scientometric analysis was performed to evaluate scientific interest in various hard substrates in studies exploring the influence of spatial heterogeneity on meiofaunal colonization. A total of 124 articles published from 1967 to 2023 were selected from online databases. Macroalgae were the most frequently studied hard substrate, and it was the one that harbors the highest abundance and richness values compared to other substrates. Studies predominantly focused on specific taxonomic groups, particularly Copepoda, Harpacticoida, and Ostracoda. Nematoda, Copepoda, Harpacticoida, and Amphipoda were the most commonly recorded meiofaunal taxa. Geographically, the United States of America was the most productive country in this field, followed by Brazil. Multivariate analyses, especially Non-Metric Multidimensional Scaling (nMDS), were the primary quantitative methods used. A decline in studies on meiofauna-substrate relationships over recent years was observed. Given the extensive research on macroalgal colonization, future studies should consider a wider variety of hard substrates to expand understanding in this field.
We have little understanding of the evolution of modern marine faunas from the European Atlantic coasts. In NW France very rich Neogene and early Quaternary mollusc assemblages occur that may shed light on the evolution of these modern faunas. Here we describe a Gelasian gastropod assemblage consisting of 76 species-level taxa from Selsoif (Manche, France), recovered from a sand extraction site between 1989-2020 by various collectors. The fauna reflects a range of intertidal to shallow subtidal palaeoenvironments. A few reworked Eocene fossils were also recovered. The extant portion of the Selsoif fauna is dominated by species with a Lusitanian signature, but also contains common species
that nowadays have a Boreal-Celtic and Mediterranean signature. Furthermore, the fauna has quite
some species in common with Early Pleistocene North Sea Basin faunas and also contains a few endemic species such as Calliostoma normanensis n. sp., Seila quinquecarinata n. sp., Alvania selsoifensis n. sp., Admete trigostomoides n. sp. The Selsoif fauna therefore represents a transitional fauna between Neogene and modern marine faunas of the European Atlantic.
The kelp Laminaria hyperborea is regularly harvested along the Norwegian coast. Kelp trawling is regulated by restricting this to every 5th year in specified areas. The kelp plants form dense forests, 1–2 m high, and house a large number of epiphytes and associated invertebrates. Kelp, epiphytes, and holdfast (hapteron) fauna were sampled at two different regions in untrawled kelp forest and at sites trawled different number of years ago. We have examined the rate of kelp regrowth after trawling, and in what time scale the associated flora and fauna colonize the trawled areas. The trawl removed all adult kelp plants (the canopy plants), while small understorey kelp plants were left undisturbed. These recruits, given improved light conditions, made the new generation of canopy-forming kelp plants, exceeding a height of 1 m within 2–3 y. The recruitment pattern of the kelp ensures maintenance of kelp forest dominance despite repeated trawling. Both percent cover, abundance and number of epiphytic species increased with time post trawling, but epiphytic communities were not totally re-established before the next trawling episode. Colonization of most species of fauna inhabiting the kelp holdfast were found as early as one year after trawling, but increasing size of the habitat by age of kelp gave room for increasing numbers of both individuals and species. Slow colonization rate by some species might be due to low dispersal potential. Due to a higher maximum age and size of kelp plants in the northernmost region studied, restoration of both kelp and kelp forest community was slower there.
Eight populations of Laminaria hyperborea from wave-exposed localities in Finnmark (70-71-degrees-N) were compared with two populations in Vega (65-degrees-N). Standing stock in shallow water (3-5 m) was within the same range in the two areas (6-16 kg fr. wt. m-2). Both the highest and lowest value of standing stock were registered in Finnmark. Degree of wave-exposure was determined by the numbers of sectors exposed to open sea at each locality, with each sector given a relative wind force value. The most wave-exposed locality in Vega had a slightly higher annual biomass production as a function of plant age compared with the populations from Finnmark within a similar range of wave exposure. Of the two localities in Vega the most wave-exposed one had a higher annual biomass production per plant than the more sheltered one. The most wave-exposed locality examined was situated in Finnmark and exhibited the lowest annual biomass production per plant. Recruits (one-year-old plants) were found at all the localities except at one locality in Finnmark. The plants reached a higher age in Finnmark (13-18 years) than in Vega (8-9 years).
A sample of giant kelp, Laminaria hyperborea Gunn. (Foslie), was made outside Vega (Nordland county), an area with varying densities of the green sea urchin Strongylocentrotus droebachiensis. The kelps were collected from one station with low (Bremstein), and one with heavy (Indreskjaer) grazing pressure. Algal epiphytes on the kelp stipes were examined. A total of 45 species was found; 31 red, 10 brown, and 4 green algae. The most common species were Polysiphonia stricta, Audouinella purpurea, Palmaria palmata and Ptilota gunneri. The average number of epiphytic algae was higher at the station with heavy grazing pressure, than at the station with low grazing pressure. Crustose algae were most abundant at the station with low grazing pressure.
