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Dan A. Smale - One of the best experts on this subject based on the ideXlab platform.
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Environmental and ecological factors influencing the spillover of the non-native kelp, Undaria pinnatifida, from marinas into natural rocky reef communities
Biological Invasions, 2018Co-Authors: Graham Epstein, Dan A. SmaleAbstract:The 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.
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Undaria pinnatifida: A case study to highlight challenges in marine invasion ecology and management.
Ecology and evolution, 2017Co-Authors: Graham Epstein, Dan A. SmaleAbstract:Marine 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.
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The influence of native macroalgal canopies on the distribution and abundance of the non-native kelp Undaria pinnatifida in natural reef habitats
Marine Biology, 2017Co-Authors: Rebecca Leij, Graham Epstein, Matthew P. Brown, Dan A. SmaleAbstract:The Asian kelp Undaria pinnatifida (‘Wakame’) is one of the most widespread invasive non-native species in coastal marine habitats and is fast approaching cosmopolitan status, yet its interactions with native species are poorly understood. Within the Plymouth Sound (UK) Special Area of Conservation (SAC), Undaria has become a conspicuous and important component of assemblages in shallow rocky reef habitats, where it co-exists with native canopy-forming brown macroalgae. We examined the hypothesis that rocky reef habitats supporting dense macroalgal canopies will have more biotic resistance to the invasion of Undaria compared with reef habitats supporting disturbed or sparse native canopies. Field surveys were completed at two spatial scales and sampling resolutions, and a short-term field-based canopy removal experiment was conducted to examine the influence of native macroalgal assemblages on the abundance, cover, biomass and morphology of Undaria . Field surveys indicated that Undaria was negatively related to the cover of macroalgal ‘competitors’, particularly Laminaria spp. However, multiple, large Undaria sporophytes were observed within dense native canopies, suggesting that disturbance to, or the absence of, canopies is not a prerequisite for Undaria colonisation. The short-term canopy removal experiment indicated that Undaria functions primarily as a pioneer species in this system. Where native canopies were left intact, Undaria sporophytes were far less abundant and were generally smaller with lower biomass compared with those in disturbed patches. The spread of Undaria into natural habitats is inhibited by the presence of native competitors, particularly large perennial species such as Laminaria spp., although the persistence of intact dense canopies does not completely prevent assimilation of Undaria into native assemblages.
Graham Epstein - One of the best experts on this subject based on the ideXlab platform.
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The ecology, impact and management feasibility of the invasive kelp Undaria pinnatifida in the UK
2019Co-Authors: Graham EpsteinAbstract:The invasive kelp Undaria pinnatifda has a global non-native range and is considered one of 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 techniques were implemented in rocky reefs and marinas of the southwest UK to better support the design and prioritisation of management, and to advance ecological understanding of marine invasive species more generally. This thesis consistently highlighted that marinas are paramount to the successful spread, proliferation and reproductive fitness of Undaria. Excluding or limiting its abundance in marinas may, therefore, restrict the likelihood of its spread to new regions and its proliferation to surrounding natural habitats. Management feasibility, however, was considered to be low, due to targeted removal measures in marinas altering recruitment patterns and even promoting total recruitment, and the high inter-habitat and inter-annual variation recorded in Undaria population dynamics. Within natural rocky reef habitats, Undaria was absent or found in low abundance in areas of high wave exposure, high desiccation stress, and where there was high abundance of the native perennial Laminaria spp.. Undaria is therefore likely to be restricted in the potential range into which it can proliferate. Where Undaria had invaded rocky reef communities, there was a consistent and significant impact upon the native annual canopy-forming macroalgae S. polyschides. The overall ecosystem impact of Undaria on rocky reef communities of the UK, however, is likely to be small, with no consistent impacts identified for any other macroalgal species, including the canopy dominant Laminaria spp.. There are cases where targeted management of Undaria may be proportionate and feasible; however, in many locations around the UK, Undaria is likely to remain unmanaged and will become an accepted part of the biota. How science and policy reacts to the continued spread and proliferation of Undaria may influe
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Environmental and ecological factors influencing the spillover of the non-native kelp, Undaria pinnatifida, from marinas into natural rocky reef communities
Biological Invasions, 2018Co-Authors: Graham Epstein, Dan A. SmaleAbstract:The 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.
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Undaria pinnatifida: A case study to highlight challenges in marine invasion ecology and management.
Ecology and evolution, 2017Co-Authors: Graham Epstein, Dan A. SmaleAbstract:Marine 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.
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The influence of native macroalgal canopies on the distribution and abundance of the non-native kelp Undaria pinnatifida in natural reef habitats
Marine Biology, 2017Co-Authors: Rebecca Leij, Graham Epstein, Matthew P. Brown, Dan A. SmaleAbstract:The Asian kelp Undaria pinnatifida (‘Wakame’) is one of the most widespread invasive non-native species in coastal marine habitats and is fast approaching cosmopolitan status, yet its interactions with native species are poorly understood. Within the Plymouth Sound (UK) Special Area of Conservation (SAC), Undaria has become a conspicuous and important component of assemblages in shallow rocky reef habitats, where it co-exists with native canopy-forming brown macroalgae. We examined the hypothesis that rocky reef habitats supporting dense macroalgal canopies will have more biotic resistance to the invasion of Undaria compared with reef habitats supporting disturbed or sparse native canopies. Field surveys were completed at two spatial scales and sampling resolutions, and a short-term field-based canopy removal experiment was conducted to examine the influence of native macroalgal assemblages on the abundance, cover, biomass and morphology of Undaria . Field surveys indicated that Undaria was negatively related to the cover of macroalgal ‘competitors’, particularly Laminaria spp. However, multiple, large Undaria sporophytes were observed within dense native canopies, suggesting that disturbance to, or the absence of, canopies is not a prerequisite for Undaria colonisation. The short-term canopy removal experiment indicated that Undaria functions primarily as a pioneer species in this system. Where native canopies were left intact, Undaria sporophytes were far less abundant and were generally smaller with lower biomass compared with those in disturbed patches. The spread of Undaria into natural habitats is inhibited by the presence of native competitors, particularly large perennial species such as Laminaria spp., although the persistence of intact dense canopies does not completely prevent assimilation of Undaria into native assemblages.
Maria Luz Piriz - One of the best experts on this subject based on the ideXlab platform.
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the invasive kelp Undaria pinnatifida phaeophyceae laminariales reduces native seaweed diversity in nuevo gulf patagonia argentina
Biological Invasions, 2004Co-Authors: Graciela N Casas, Ricardo Augusto Scrosati, Maria Luz PirizAbstract:The kelp Undaria pinnatifida(Phaeophyceae) is a seaweed native to northeast Asia, but during the last two decades, it has been accidentally or intentionally introduced in several temperate coasts worldwide. In central Patagonia (Argentina), this species was first detected in late 1992, and it is progressively spreading from the point of introduction. Through a manipulative experiment involving Undaria removal in 2001, we found that its presence is associated with a dramatic decrease in species richness and diversity of native seaweeds in Nuevo Gulf. Future prospects are worrisome, as, in addition to the negative impact from a biodiversity viewpoint, native commercial macroalgae and invertebrates might also be affected.
Robert M. Lafrenie - One of the best experts on this subject based on the ideXlab platform.
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Uncaria tomentosa acts as a potent TNF-α inhibitor through NF-κB.
Journal of ethnopharmacology, 2009Co-Authors: Lisa Allen-hall, John T. Arnason, Pablo Cano, Robert M. LafrenieAbstract:Abstract Aim of the study Uncaria tomentosa , commonly known as Cat's Claw or Una de gato , is a medicinal plant that has been shown to have effective anti-inflammatory activities. We have previously shown that treatment of monocyte-like THP-1 cells with Uncaria tomentosa inhibits the production of the pro-inflammatory cytokine TNF-α while augmenting the production of IL-1β. Since TNF-α and IL-1β are usually regulated similarly and share a number of common promoter elements, including NF-κB and AP-1, the ability of Uncaria tomentosa to differentially regulate these inflammatory cytokines is of particular interest. Materials and methods To determine the mechanism of action of Uncaria tomentosa, we investigated the effects of specific inhibitors of NF-κB on cellular responses including transcription factor activation using TransAM assays, the expression of cytokines as measured by ELISA, and cell survival as measured by changes in cell number following treatment. Results Treatment with Uncaria tomentosa inhibited the LPS-dependent activation of specific NF-κB and AP-1 components. In addition, treatment with Uncaria tomentosa enhanced cell death when NF-κB was inhibited. The ability of Uncaria tomentosa to inhibit TNF-α production was diminished when NF-κB activation was prevented by drugs that mask NF-κB subunit nuclear localization signals, while IL-1β expression was unchanged. Conclusions These results demonstrate that Uncaria tomentosa is able to elicit a response via an NF-κB-dependent mechanism. Further studies to characterize the mechanism by which Uncaria tomentosa can affect this pathway could provide a means to develop anti-TNF-α therapies.
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Treatment of THP-1 cells with Uncaria tomentosa extracts differentially regulates the expression if IL-1β and TNF-α
Journal of ethnopharmacology, 2006Co-Authors: Lisa Allen-hall, John T. Arnason, Pablo Cano, Rosario Rojas, Olga Lock, Robert M. LafrenieAbstract:Uncaria tomentosa, commonly known as cat's claw, is a medicinal plant native to Peru, which has been used for decades in the treatment of various inflammatory disorders. Uncaria tomentosa can be used as an antioxidant, has anti-apoptotic properties, and can enhance DNA repair, however it is best know for its anti-inflammatory properties. Treatment with Uncaria tomentosa extracts inhibits the production of the pro-inflammatory cytokine, TNF-alpha, which is a critical mediator of the immune response. In this paper, we showed that treatment of THP-1 monocyte-like cells with Uncaria tomentosa extracts inhibited the MAP kinase signaling pathway and altered cytokine expression. Using ELISA assays, we showed that treatment with Uncaria tomentosa extracts augmented LPS-dependent expression of IL-1beta by 2.4-fold, while inhibiting the LPS-dependent expression of TNF-alpha by 5.5-fold. We also showed that treatment of LPS-stimulated THP-1 cells with Uncaria tomentosa extracts blocked ERK1/2 and MEK1/2 phosphorylation in a dose-dependent manner. These data demonstrate that treatment of THP-1 cells with Uncaria tomentosa extracts has opposite effects on IL-1beta and TNF-alpha secretion, and that these changes may involve effects on the MAP kinase pathway.
Dougal J Fergus - One of the best experts on this subject based on the ideXlab platform.
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Eradication success down under: heat treatment of a sunken trawler to kill the invasive seaweed Undaria pinnatifida.
Marine pollution bulletin, 2004Co-Authors: Debra M Wotton, Chris O'brien, Mike D Stuart, Dougal J FergusAbstract:Eradication of invasive species is difficult in the marine environment, and there have only been a few successes. We report the successful eradication of the invasive seaweed Undaria pinnatifida from a sunken trawler in the Chatham Islands, New Zealand. New heat-treatment methods were developed as the most cost effective and environmentally acceptable option to kill Undaria. Monitoring of the trawler for three years after it sank found no Undaria after the vessel was treated. Key factors in the success of the eradication programme included: early detection, a rapid response, pre-existing knowledge of Undaria, an adaptive management approach, targeting of multiple life history stages, and the cooperation of the vessel's insurer.
