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Dataset for - The ecology, impact and management feasibility of the invasive kelp Undaria pinnatifida in the UK
No full textThis dataset supports the PhD Thesis:
Epstein, G. The ecology, impact and management feasibility of the invasive kelp Undaria pinnatifida in the UK</span
The ecology, impact and management feasibility of the invasive kelp Undaria pinnatifida in the UK
No full textThe invasive kelp Undaria pinnatifda has a global non-native range and is considered oneof the “world's worst invasive species". It has been present in the UK for at least 25 years;however given its status, there remains a dearth of information regarding its ecology,impacts and management feasibility. A variety of surveys and manipulative techniqueswere implemented in rocky reefs and marinas of the southwest UK to better supportthe design and prioritisation of management, and to advance ecological understandingof marine invasive species more generally. This thesis consistently highlighted thatmarinas are paramount to the successful spread, proliferation and reproductive fitnessof Undaria. Excluding or limiting its abundance in marinas may, therefore, restrictthe likelihood of its spread to new regions and its proliferation to surrounding naturalhabitats. Management feasibility, however, was considered to be low, due to targetedremoval measures in marinas altering recruitment patterns and even promoting totalrecruitment, and the high inter-habitat and inter-annual variation recorded in Undariapopulation dynamics. Within natural rocky reef habitats, Undaria was absent or foundin low abundance in areas of high wave exposure, high desiccation stress, and where therewas high abundance of the native perennial Laminaria spp.. Undaria is therefore likelyto be restricted in the potential range into which it can proliferate. Where Undaria hadinvaded rocky reef communities, there was a consistent and significant impact upon thenative annual canopy-forming macroalgae S. polyschides. The overall ecosystem impactof Undaria on rocky reef communities of the UK, however, is likely to be small, withno consistent impacts identified for any other macroalgal species, including the canopydominant Laminaria spp.. There are cases where targeted management of Undaria maybe proportionate and feasible; however, in many locations around the UK, Undaria islikely to remain unmanaged and will become an accepted part of the biota. How scienceand policy reacts to the continued spread and proliferation of Undaria may influe<br/
Environmental and ecological factors influencing the spillover of the non-native kelp, Undaria pinnatifida, from marinas into natural rocky reef communities
No full textThe non-native kelp, Undaria pinnatifida, is considered one of the world’s worst invasive species. The northeast Atlantic is a hotspot of Undaria invasion, yet there is limited knowledge on its invasion dynamics. In the UK its distribution is strongly associated with artificial structures, primarily marina and harbour pontoons, with relatively few records of Undaria on natural substrates. Here, the southwest UK is used as a case region, to explicitly link Undaria distribution-abundance patterns in artificial marina habitats with those in natural rocky reef habitats. Using a mixture of in situ recording and video survey techniques, Undaria was found at all thirteen marina sites surveyed; but in only 17 of 35 rocky reef sites, all of which were in 2 of the 5 larger systems surveyed (Plymouth Sound and Torbay). The distribution-abundance patterns of Undaria at reef sites were analysed using zero-inflated models. The probability of finding Undaria on rocky reef increased with increasing proximity to marinas with high abundances of Undaria. Total propagule pressure from marinas also increased the probability of occurrence, and was positively related to Undaria abundance and cover at reef sites. Increases in the cover of native kelps, Laminaria spp., and wave exposure at reef sites were linked to a reduced probability of Undaria occurrence, and lower abundance and cover. Identifying high risk areas, natural boundaries and factors affecting the spread and abundance of non-native species in natural habitats is key to future management prioritisation. Where Undaria is confined to artificial substrates management may be deemed a low priority. However, the results of this study suggest that controlling the abundance and propagule pressure in artificial habitats may limit, to some extent, the spillover of Undaria into natural rocky reef habitats, where it has the potential to interact with and influence native communities
Between-habitat variability in the population dynamics of a global marine invader may drive management uncertainty
Full text linkUnderstanding population dynamics of established invasive species is important for designing effective management measures and predicting factors such as invasiveness and ecological impact. The kelp Undaria pinnatifida has spread to most temperate regions of the world, however a basic understanding of population dynamics is lacking for many regions. Here, Undaria was monitored for 2 years, at 9 sites, across 3 habitats to investigate habitat-related variation in population structure, reproductive capacity and morphology. Populations on marina pontoons were distinct from those in reef habitats, with extended recruitment periods and higher abundance, biomass, maturation rates and fecundity; potentially driven by lower inter-specific and higher intra-specific competition within marinas. This suggests that artificial habitats are likely to facilitate the spread, proliferation and reproductive fitness of Undaria across its non-native range. More broadly, generalising population dynamics of invasive species across habitat types is problematic, thus adding high complexity to management options
Predictive maps and related data on organic carbon stocks in surficial sediments of the Canadian continental margin
No full textThis repository contains predictive maps of mud content, carbon content, dry bulk density and organic carbon density in surficial seabed sediments of the Canadian continental margin. These each include the mean predictions as well as the lower and upper uncertainty bounds. Additionally, data are presented from a systematic data review of organic carbon content in seabed sediments across Canada, and from two regional case studies on the influence of the predicted distribution of rock habitats. All the associated code used for data manipulations, model building and predictive mapping are also published herein. Data are organised across five folders. Please see the individual readme files within each folder and the associated published paper for further information
Priority areas for research and potential protection of seabed sediment carbon on Canada's continental margin - outputs and associated R code.
No full textThis repository contains a shapefile (PA_Shapefile.zip) delineating possible priority areas for research and potential protection of seabed sediment carbon within marine protected and conserved areas (MCAs) on Canada's continental margin. Areas were identified by selecting seabed sediments of high carbon density that lie outside of current MCAs. All areas were then ranked upon: 1) mean carbon density (including estimated uncertainty), 2) total carbon stock (including estimated uncertainty), 3) estimated mean mud content, 4) distance to shore, and 5) the proportion of the area which lies within Ecologically and Biologically Significant Areas; with the sum of these 5 rankings taken as a general metric for potential overall priority. All the associated code used for data manipulations, and file construction are also published here. The code file also contains exploratory analyses on the coverage of seabed sediment carbon by designated and proposed MCAs in Canada. Please see the readme file and the associated published paper for further information
Undaria pinnatifida : A case study to highlight challenges in marine invasion ecology and management
No full textMarine invasion ecology and management have progressed significantly over the last 30 years although many knowledge gaps and challenges remain. The kelp Undaria pinnatifida, or “Wakame,” has a global non-native range and is considered one of the world's “worst” invasive species. Since its first recorded introduction in 1971, numerous studies have been conducted on its ecology, invasive characteristics, and impacts, yet a general consensus on the best approach to its management has not yet been reached. Here, we synthesize current understanding of this highly invasive species and adopt Undaria as a case study to highlight challenges in wider marine invasion ecology and management. Invasive species such as Undaria are likely to continue to spread and become conspicuous, prominent components of coastal marine communities. While in many cases, marine invasive species have detectable deleterious impacts on recipient communities, in many others their influence is often limited and location specific. Although not yet conclusive, Undaria may cause some ecological impact, but it does not appear to drive ecosystem change in most invaded regions. Targeted management actions have also had minimal success. Further research is needed before well-considered, evidence-based management decisions can be made. However, if Undaria was to become officially unmanaged in parts of its non-native range, the presence of a highly productive, habitat former with commercial value and a broad ecological niche, could have significant economic and even environmental benefit. How science and policy reacts to the continued invasion of Undaria may influence how similar marine invasive species are handled in the future
Removal treatments alter the recruitment dynamics of a global marine invader - implications for management feasibility
No full textFrameworks designed to prioritise the management of invasive non-native species (INNS) must consider many factors, including their impacts on native biodiversity, ecosystem services, and human health. Management feasibility should also be foremost in any prioritisation process, but is often overlooked, particularly in the marine environment. The Asian kelp, Undaria pinnatifida, is one of the most cosmopolitan marine INNS worldwide and recognised as a priority species for monitoring in the UK and elsewhere. Here, experimental monthly removals of Undaria (from 0.2 m2 patches of floating pontoon) were conducted at two marinas to investigate their influence on recruitment dynamics and the potential implications for management feasibility. Over the 18-month experiment there was no consistent reduction in Undaria recruitment following removals. Cleaning of pontoon surfaces (i.e. removal of all biota) led to significant short-term reductions in recruitment but caused a temporal shift in normal recruitment patterns. Non-selective removal (i.e. all macroalgae) generally promoted recruitment, while selective removal (i.e. Undaria only) had some limited success in reducing overall recruitment. The varied results indicate that the feasibility of limiting Undaria is likely to be very low at sites with established populations and high propagule pressure. However, where there are new incursions, a mixture of cleaning of invaded surfaces prior to normal periods of peak recruitment followed by selective removal may have some potential in limiting Undaria populations within these sites. Multi-factorial experimental manipulations such as this are useful tools for gathering quantitative evidence to support the prioritisation of management measures for marine INNS
Identifying niche and fitness dissimilarities in invaded marine macroalgal canopies within the context of contemporary coexistence theory
Full text linkContemporary coexistence theory provides a framework for predicting invasiveness and impact of Invasive Non-Native Species (INNS) by incorporating differences in niche and fitness between INNS and co-occurring native species. The widespread invasive kelp Undaria pinnatifida is considered a high-risk INNS, although a robust evidence base regarding its invasiveness and impact is lacking in many regions. Invaded macroalgal canopies at nine coastal sites in the southwest UK were studied over three years to discern whether Undaria is coexisting or competing with native canopy-forming species across different habitat types. Spatial, temporal and depth-related trends in species distributions and abundance were recorded within intertidal and subtidal rocky reef as well as on marina pontoons. A primary succession experiment also examined competitive interactions between species. In rocky reef habitats, Undaria had lower fitness compared to long-lived native perennials, but was able to coexist due to niche dissimilarity between species. In contrast, Undaria was likely to be competing with short-lived native annuals on rocky reef due to large niche overlap and similar fitness. In marina habitats, Undaria dominated over all other canopy formers due to low niche diversification and higher fitness. Generalisations on INNS impact cannot be made across habitats or species, without considering many abiotic factors and biotic interactions.</p
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