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Pacifastacus leniusculus
Signal Crayfish
The signal crayfish is a large North American freshwater crayfish introduced to Europe in the 1960s to replace declining native fisheries. It has become one of the most ecologically impactful invasive decapods in Europe, outcompeting native crayfish and serving as a carrier of crayfish plague (Aphanomyces astaci). The species establishes self-sustaining populations rapidly, with six age cohorts documented within a few years of introduction. It shows sex- and size-specific coloration patterns, with males displaying more saturated and brighter ventral claw surfaces than females, suggesting a role in intraspecific communication.
invasive-species crayfish-plague-carrier decapod freshwater-crustacean conservation-concern species-of-Union-concern early-detection-rapid-response ark-sites ecosystem-engineer bioaccumulation sexual-dimorphism nocturnal-activity invasion-gradient trapping electrofishing eradication Mediterranean-invasion headwater-threat native-crayfish-displacement fisheries-introduction 1960s-introduction Europe Japan California-native Pacifastacus Astacidae Decapoda Malacostraca Arthropoda Aphanomyces-astaci white-clawed-crayfish signal-crayfish control-planning removal-actions catch-per-unit-effort color-variation carotenoids camouflage conspicuousness intraspecific-communication elemental-accumulation contaminant trophic-level macroinvertebrate plant-detritus riffle stream river lake tributary invasion-front core-population exploratory-behavior migration-patterns ontogenetic-color-change kick-sampling detection-protocol false-negative Catalonia Italy Portugal Spain Poland Scandinavia British-Isles Segura-River Clitunno-River Valla-stream Rabaçal-River Fosso-Vecchio Union-concern LIFE-IMAGINE eradication-attempt biosecurity pathway-action-plans INNS-inspectorate environmental-DNA eDNA host-pathogen-dynamics conservation-translocation ark-site aggregates-levy environment-agency BBC-wildlife-fund defra habitats-directive favourable-conservation-status unfavourable-bad extinction-risk funding-cuts ecosystem-services keystone-species woodland pollination decomposition nutrient-cycling predation water-purification citizen-science ex-situ-conservation-rearing zoos aquaria Fen-Raft-Spider Pond-Mud-Snail Large-Marsh-Grasshopper Freshwater-Pearl-Mussel Marbled-White-Butterfly Small-Skipper climate-change assisted-colonization range-margin biotic-response abiotic-driver warming pollution eutrophication functional-trait thermal-limit embryogenesis competitive-advantage alien-aquatic-species artificial-light-at-night nutrient-enrichment brown-trout biological-control clearance-rate parasite-load sympatry global-invader predatory-interaction experimental-approach epiphytic-algae submerged-plant-community molecular-tools informatics social-media pooled-sampling integrative-taxonomy hybrid bryozoan cost-efficient-methodology policy-effectiveness legislative-tools LIFE-INVASAQUA networking prevention awareness marine-protected-area citizen-science-data non-native-freshwater-fish knowledge-gaps invasive-alien-freshwater-plants naturalised-plants aquatic-habitats pot-plants horticulture New-Guinea-flatworm Partula-tree-snails Lob-worm Lumbricus-terrestris Harlequin-ladybird Oak-processionary-moth New-Zealand-flatworm Australian-flatworm Lily-beetle Rosemary-leaf-beetle Spanish-slug Girdled-snail Australian-landhopper Light-brown-apple-moth Asian-hornet Argentine-ant Linepithema-humile Vespa-velutina ash-dieback Hymenoscyphus-fraxineus Floating-Pennywort Giant-Hogweed Chinese-Mitten-Crab Eriocheir-sinensis Ballast-Water-Convention Office-for-Environmental-Protection Environmental-Improvement-Plan Global-Biodiversity-Framework delisting listing rapid-response Great-Britain-Non-native-Species-Strategy Nature-2030 Wildlife-and-Countryside-Link Buglife invertebrate conservation reintroduction reinforcement assisted-colonisation habitat-management genetic-diversity donor-stock stakeholder-collaboration Natural-England eNGO landowner public-engagement media-attention tabloid sensationalism spider size-of-rats Marvellous-Mud-Snails-Cornwall Citizen-Zoo Hop-of-Hope volunteer ex-situ-rearing long-life-cycle glochidia salmonid-fish-host Freshwater-Biology-Association juvenile-mussel habitat-restoration micro-habitat Field-Cricket Wart-biter-Bush-cricket Barberry-Carpet-Moth Marsh-Fritillary-Butterfly Fisher's-Estuarine-Moth Southern-Damselfly White-faced-Darter-Dragonfly Pine-Hoverfly Dark-bordered-Beauty-Moth Medicinal-Leech Tadpole-Shrimp Netted-Carpet-Moth Ladybird-Spider Narrow-headed-Ant Cumbria Dorset Devon microhabitat low-mobility natural-colonization short-haired-bumblebee Bombus-subterraneus sub-optimal-management Barberry-bush Paul-Waring Benoit-Guénard conservation-funding vertebrate-bias invertebrate-neglect beaver Castor-fiber pine-marten Martes-martes bird-of-prey Large-Blue-Butterfly Phengaris-arion Chequered-Skipper Carterocephalus-palaemon mainland-Europe national-reintroduction local-reintroduction donor-population receptor-site county 400-m isolated-habitat England-Species-Reintroduction-Task-Force Karim-Vahed half-a-century diverse-species logistically-easier guidelines code government habitat-conditions site-conditions targeted-habitat-management mobility recovery unsuccessful-case lack-of-genetic-diversity optimal-management establishment-failure care knowledge funding-allocation PNAS threatened-species 80%6%species-numbers imbalance legislation wild-release high-profile main-image Decticus-verrucivorus Dr-Sarah-Henshall share Facebook LinkedIn Trinity-Audio tweet NEOBIOTA-2024 Lisbon 421-participants 47-countries invasion-science aquatic-studies marine freshwater oral-session poster workshop NeoBiota-Special-Issue editorial Pedro-Anastácio Filipe-Ribeiro Paula-Chainho 23-papers five-themes 100th-issue ZooKeys digital-taxonomy environmental-stressor invasion-success salinity sea-level-rise Alternanthera-philoxeroides stress-tolerance avoidance escape Gonçalves physiological-performance Callinectes-sapidus climate-warming Phymactis-papillosa environmental-tolerance ecological-impact Portuguese-intertidal synergistic-effect Zhang ecological-interaction invasion-impact population-dynamics Salmo-trutta Matos bivalve capture-efficiency natural-seston Cabral Eupercaria Tkachenko global-aquatic-invader Reshetnikov Pontederia-crassipes Pistia-stratiotes Shen detection monitoring surveillance early-detection Dias Xenopus-laevis pooled-eDNA Everts Squalius Gkenas Chilean-SE-Pacific Rech management policy legislative-tool EU-policy sectoral-impact Magliozzi freshwater-turtle Rato Carosi habitat-use trapping-efficiency hypersaline-lagoon Herrero-Reyes Iberian-Peninsula López-Cañizares African-marine-protected-area global-database Ackland Indian-freshwater-fish evidence-gap Kumar European-freshwater-plant ecosystem-impact Di-Lernia global-synthesis naturalised-plant aquatic-habitat Kortz interdisciplinarity translational-relevance issue-4930 Bluesky scholarly-publishing ecology invasion-ecology aquatic-ecosystem flatworm snail gang-attack extinction pot-plant soil-sterilization fumigation hot-water-immersion biosecurity-measure international-trade Hirudo-medicinalis Neil-Phillips Steven-Falk Sarah-Henshall omphiscola-glabra Cornwall Scotland Blera-fallax Epione-vespertaria Triops-cancriformis Eustroma-reticulatum Eresus-sandaliatus Formica-exsecta Gryllus-campestris Decticus-verrucivorous Pareulype-berberata Euphydryas-aurinia Margaritifera-margaritifera Gortyna-borelii-lunata Dolomedes-plantarius Coenagrion-mercuriale Leucorrhinia-dubia Stethophyma-grossum Melanargia-galathea Thymelicus-sylvestris Formica-rufa Kielder-Forest Northumberland Liz-Oldring Stephen-Wills Durham-University climate-suitability limited-funding biased-funding vertebrate nature-positive-trade 2024-General-Election Manifesto-for-Bugs seven-actions commitments halting-nature-loss reversing-invertebrate-decline Andrew-Whitehouse South-West-Manager Lord-De-Mauley wildlife-minister mineral-extraction Treasury George-Entwistle 50%-cut badger-cull river-dredging £100K £12.75 £420 £1,616 2012 2014 21-projects 2-projects reporting Bedstraw-hawk-moth national-pride leadership David-Smith Social-Change-and-Advocacy-Officer Lisa-Manning Policy-and-Engagement-Officer February-2024 GB-Non-Native-Species-Strategy one-year-anniversary measurability timeline off-track 2030 time-lag establishment Red-Imported-Fire-Ant Solenopsis-invicta world's-worst-invasive-species PaPs draft-form consultation-delay 2023-State-of-Nature-Report Environmental-Audit-Committee £6-million animal-health plant-health resourcing long-term-future slipped-timelines inefficient-process fully-resourced-implementation-plans general-election manifesto smallest-creatures foundations healthy-environment ecosystem-function nature's-decline action commitment England-Manager deliberate-movement release wild conservation-purpose feathered furred multitude large-scale 1980s 1990s 2018 England small-size small-scale region 2005 2007 2008 2010-2015 2009 2010 2019 2022 2023 isolated high-reproductive-potential cost-effective zoo aquarium collaboration ten-different-zoos thousands spiderlings four-new-populations Norfolk Suffolk media-response 2024 headline homeowner urgent-warning relatively-easy-to-rear local-schools colleges volunteers small-aquaria 500-snails four-new-sites 6,000 47-volunteers long-complex-life-cycle long-lived many-years 50,000 specialised-facilities hundreds juvenile-mussels ageing-populations Northern-England natural-range conservation-status 2000 climatically-suitable nine-years pest-species Forestry-England Wood-Ant keystone-woodland-species rescue immediate-danger Austropotamobius-pallipes North-American-Signal-Crayfish Pacifastacus-leniusculus outcompetes fungal Crayfish-Plague susceptible successful-reintroduction rigorous-planning appropriate-guidelines reintroduction-code natural-habitat restoration micro-habitat-requirements life-cycle-stage conservation-tool-kit targeted-habitat-restoration mobile-species species-specialist public 2010s 2004 thousands-of-caterpillars multiple-attempts public-attention vertebrate-relative 2025 opposite-pattern celebration