Overvåking av spredningsveien import av planteprodukter: Basisovervåking 2023 og ti års oppsummering

Davey, M.L., Westergaard, K.B., Endrestøl, A., Fossøy, F., Hanssen, O., Brandsegg, H., Laugsand, A.E., Opsahl, N.N., Dahle, S., Andersskog, I.P.Ø., Staverløkk, A., Åström, J. 2024. Overvåking av spredningsveien import av planteprodukter: Basisovervåking 2023 og ti års oppsummering. NINA Rapport 2484. Norsk institutt for naturforskning. Fremmede arter er regnet som en av de største truslene mot verdens biologiske mangfold. De kan medføre store økologiske og samfunnsøkonomiske kostnader, og de kan være svært kostnadskrevende å bekjempe. Det mest kostnadseffektive tiltaket mot fremmede arter er å forhindre introduksjonen og redusere spredningen ved å oppdage dem tidlig. Gjennom overvåking av deres spredningsveier er det mulig å oppdage artene i introduksjonsfasen av invasjonen og dermed kunne iverksette tiltak for å begrense spredningen så tidlig som mulig. Prosjektet «Overvåking av spredningsveien import av planteprodukter», utført på oppdrag for Miljødirektoratet, har som mål å kostnadseffektivt overvåke og beregne kvantitativt hvor mange fremmede arter som kommer til Norge som blindpassasjerer via spredningsveien import av planteprodukter, og hvilken risiko disse utgjør for det stedegne biologiske mangfoldet. Her rapporterer vi metode og resultater for 2022 og 2023, og vi gjør en oppsummering av dataene fra 2014-2023. I tillegg rapporterer vi for opsjonen «Bruk av ny teknologi», hvor målet har vært å vurdere DNA strekkoding som en metode for å identifisere plantespirer fra spireforsøker av frø som følger med den importerte plantejorda som «forurensing». I 2023 har vi videreført basisovervåkingen som ble etablert i tidligere år med innsamling av levende invertebrater fra jordprøver, bankeprøver og lysfeller (innendørs på importlokaliteter) og spiring av karplanter fra jordprøver fra importerte hageplanter. Det ble tatt prøver av 17 konteinere, som inneholdt 11 376 invertebratindivider (eksklusivt midd og spretthaler). Vi har artsidentifisert 1676 spirte frø fra jordprøvene, som inkludert 127 individer som tilhørte 8 forskjellige fremmede arter. Totalt 256 invertebratindivider ble identifisert fra bankeprøvene i 2023, og lysfellene fanget et estimert antall på 35 000 invertebratindivider. Årets arbeid på opsjonen «Bruk av ny teknologi» har fokusert på vurdering av DNA-strekkoding for identifisering av karplantespirer i vekstforsøk, og vi anbefaler at prosjektet bruker DNA strekkoding som et støtteverktøy til morfologisk artsbestemmelse for å kunne identifisere spirer som har få morfologiske karakter eller hvor man mangler riktig kunnskap for å gjøre en sikker bestemmelse. Bruk av denne metoden kan redusere sårbarhet med hensyn til mangel på taksonomiske eksperter og samtidig kan det føre til mer nøyaktig identifisering av vanskelig individer og taksa. I løpet av prosjektperioden (2014-2023) overvåket vi mellom 110 og 230 L jord (38 – 105 kg) fra importert planter hvert år, som utgjør under 0,0001% av mengden av jord og vekstmedium som årlig importeres til Norge. Over 34 000 karplanteindivider har vært identifisert og vurdert, mot Fremmedartslista og 35 fremmede arter, 4 dørstokkarter, og 24 potensielt fremmede arter oppdaget. Blant materialet fra jordprøver og lysfeller satt ut på importlokalitetene har vi vurdert litt under 175 000 invertebrater (unntatt midd og spretthaler), og oppdaget 28 fremmede og 37 dørstokkarter. I tillegg har vi oppdaget flere arter som ikke er kjent som stedegne i Norge og heller ikke er vurdert på Fremmedartslista. Disse artene kategoriseres ut fra tilgjengelig kunnskap fra resten av Europa enten som mulige stedegne arter som har ikke vært rapportert fra Norge ennå, eller potensielle fremmede arter som bør sendes til ekspertkomiteene for vurdering som dørstokkarter. Observerte oppdagelsesrater for arter som er nye for prosjektet (første oppdagelse av en fremmed/dørstokk art i løpet av prosjektet) var hovedsakelig under 5 karplantearter og 10 invertebratarter per år, og holdt seg stort sett jevnt gjennom prosjektperioden. Men disse ratene var avhengig av prøvetakingsinnsats både for planter og invertebrater, som viser at videre tolkning av introduksjonstrender basert på dataene må ta hensyn til det for å få pålitelige estimater av introduksjonsrater. Introduksjonstrykk per art var relativt lav for de fleste artene, uavhengig av risikokategori, unntatt planteartene Conyza canadensis (HI) (oppdaget fra 9% av jordprøvene, 2.7 individer/L jord) og Epilobium ciliatum subsp. ciliatum (SE) (oppdaget fra 14% av jordprøvene, >4 individer/L jord), og billen Carpelimus zealandicus (PH) (oppdaget fra 15% av jordprøvene med gjennomsnitt >35 individer/L jord), som alle hadde høye introduksjonstrykk gjennom flere år. Vi har identifisert flere mulig synergier mellom «Overvåking av spredningsveien planteimport»-programmet, andre overvåkingsprogrammer, og eksisterende strukturer for fremmedartsforvaltning som kan videreutvikles i framtiden. Vi anbefaler at eksisterende database og innsynsløsning oppdateres og forbedres for å tilgjengeliggjøre dataene fra prosjektet til videre horisontskanning og risikovurdering av arter på Fremmedartslista. Med formelle rutiner for å sette sammen forekomstdata fra «Overvåking av spredningsveien planteimport», «Tidlig oppdagelse av nye fremmede arter» og nasjonale overvåkingsprogrammer for planter og insekter er det mulig å identifisere arter som er tidlig i den biologiske invasjonsprosessen og dermed legge grunnlag for prioritering av tiltak mot fremmede arter. Pilotprosjektet på metastrekkoding har vist at i kombinasjon med programmet for Nasjonal insektovervåking har vi mulighet til å overvåke import av fremmede insekt-haplotyper i tillegg til fremmede arter, og oppdage genetisk forurensing i stedegne bestander.

Davey, M.L., Westergaard, K.B., Endrestøl, A., Fossøy, F., Hanssen, O., Brandsegg, H., Laugsand, A.E., Opsahl, N.N., Dahle, S., Andersskog, I.P.Ø., Staverløkk, A., Åström, J. 2024. Monitoring the invasion pathway of imported horticultural plants. Basic monitoring 2023 and a ten year summary of results. NINA Rapport 2484. Norwegian Institute for Nature Research. Invasive species are considered one of the most significant threats to global biodiversity and have substantial ecological and socioeconomic costs. Eradication measures are often expensive, and their success and cost effectiveness rely heavily on early detection and rapid response. Monitoring of introduction pathways detects organisms in the introduction phase of biological invasions, allowing for the implementation of control measures to minimize introduction pressure, hindering spread and further colonization. The project “Monitoring the invasion pathway of imported horticultural plants”, commissioned by the Norwegian Environment Agency aims to monitor and calculate how many invasive species arrive to Norway as contaminants and hitchhikers with plant products, and to assess the risk they pose to local biodiversity, in a cost-effective way. Here, we present the results from monitoring activities in 2023 and select activities undertaken in 2022, as well as a summary of the past ten years of monitoring (2014-2023). We also report the results from the supplementary work-package “Using new technology”, where the goal was to evaluate DNA barcoding as a method for species identification of contaminant seedlings germinated from the soil of imported plants. Basic monitoring activities continued in 2023 as in previous years, with the germination of seeds from soil samples collected from imported garden plants, and the collection of live invertebrates from soil samples, beating of plants and light-traps deployed indoors at plant import facilities. We sampled soils from 17 shipping containers and recovered 11 376 invertebrates (excluding mites and springtails). A total of 1676 viable vascular plant seeds were identified from the soil samples, including 127 individuals of 8 different invasive species. More than 250 invertebrates were sampled from the aboveground parts of the imported plants, and an estimated 35 000 invertebrates were captured in light traps deployed indoors at import facilities. Activities in this year’s “utilizing new technologies” work package focused on evaluating DNA barcoding as a method to identify vascular plant seedlings in germination trials. Based on our results, we recommend the method is implemented as a support tool for taxonomists to facilitate easier and more precise identification of particularly difficult individuals and taxa, and to compensate when specialized taxonomic expertise is lacking. Over the course of the project period and its earlier development phases we have monitored between 110 and 230 L (38-105 kg) of soil from imported plants each year, which comprises under 0.0001% of the annual mass of plants with soil and growth medium imported to Norway each year. Over 34 000 vascular plant individuals have been evaluated, and 35 invasive, 4 doorknocker, and 24 potential invasive species have been detected. Among the material from soil samples and light traps set out at import localities, we have evaluated almost 175 000 invertebrates (excluding mites and springtails) which include 28 invasive and 37 doorknocker species. A portion of the species detected are neither known to be native in Norway nor have they been evaluated for the current version of the Norwegian Invasive Species List. We have further evaluated divided this group of species into putative native species that have likely gone previously undetected in Norway, and potential invasive species that should be sent to the Norwegian Biodiversity Information Centre’s expert committees for further evaluation as doorknocker species in future horizon scanning exercises. Invasive species introduction rates (based on the first observation of an invasive/doorknocker species during the program) have typically been below 5 plant species and 10 insect species each year, with no clear positive or negative trends during the project period. However, these rates were clearly linked to sampling effort for both groups, which indicates that any interpretation of introduction trends must take sampling effort into account in order to draw robust conclusions. Introduction pressure for individual species was low for the majority of invasive and doorknocker species, regardless of their risk categories. Exceptions to this pattern were the plants Conyza canadensis (HI) occurring in 9% av soil samples with 2.7 seeds/L soil) and Epilobium ciliatum subsp. ciliatum (SE) (occurring in 14% of soil samples with >4 seeds/L soil), and the beetle Carpelimus zealandicus (PH) (occurring in 15% of soil samples with >35 individuals/L soil). We have identified several potential synergies between the “Monitoring the introduction pathway of imported horticultural plants” program, other monitoring programs, and the existing structure for managing invasive species in Norway that can be further developed in the future. We recommend establishing an improved database structure and visualization platform to ensure effective information flow from the project, so data is readily available to inform horizon scanning and further risk assessments of species on the national invasive species list. With formal routines to combine data from this project, the “Early detection of invasive species” project, and national monitoring programs for plants and insects, it is possible to identify species that are early in the biological invasion process and further inform prioritizing of species for eradication and control measures. A pilot project using metabarcoding to identify insects has shown that when combined with data from the National insect monitoring program, we have the possibility to monitor not just the import of invasive species, but also the import of foreign insect haplotypes and to identify resulting genetic pollution among populations of native species.

Davey, M.L., Westergaard, K.B., Endrestøl, A., Fossøy, F., Hanssen, O., Brandsegg, H., Laugsand, A.E., Opsahl, N.N., Dahle, S., Andersskog, I.P.Ø., Staverløkk, A., Åström, J. 2024. Monitoring the invasion pathway of imported horticultural plants. Basic monitoring 2023 and a ten year summary of results. NINA Rapport 2484. Norwegian Institute for Nature Research. Invasive species are considered one of the most significant threats to global biodiversity and have substantial ecological and socioeconomic costs. Eradication measures are often expensive, and their success and cost effectiveness rely heavily on early detection and rapid response. Monitoring of introduction pathways detects organisms in the introduction phase of biological invasions, allowing for the implementation of control measures to minimize introduction pressure, hindering spread and further colonization. The project “Monitoring the invasion pathway of imported horticultural plants”, commissioned by the Norwegian Environment Agency aims to monitor and calculate how many invasive species arrive to Norway as contaminants and hitchhikers with plant products, and to assess the risk they pose to local biodiversity, in a cost-effective way. Here, we present the results from monitoring activities in 2023 and select activities undertaken in 2022, as well as a summary of the past ten years of monitoring (2014-2023). We also report the results from the supplementary work-package “Using new technology”, where the goal was to evaluate DNA barcoding as a method for species identification of contaminant seedlings germinated from the soil of imported plants. Basic monitoring activities continued in 2023 as in previous years, with the germination of seeds from soil samples collected from imported garden plants, and the collection of live invertebrates from soil samples, beating of plants and light-traps deployed indoors at plant import facilities. We sampled soils from 17 shipping containers and recovered 11 376 invertebrates (excluding mites and springtails). A total of 1676 viable vascular plant seeds were identified from the soil samples, including 127 individuals of 8 different invasive species. More than 250 invertebrates were sampled from the aboveground parts of the imported plants, and an estimated 35 000 invertebrates were captured in light traps deployed indoors at import facilities. Activities in this year’s “utilizing new technologies” work package focused on evaluating DNA barcoding as a method to identify vascular plant seedlings in germination trials. Based on our results, we recommend the method is implemented as a support tool for taxonomists to facilitate easier and more precise identification of particularly difficult individuals and taxa, and to compensate when specialized taxonomic expertise is lacking. Over the course of the project period and its earlier development phases we have monitored between 110 and 230 L (38-105 kg) of soil from imported plants each year, which comprises under 0.0001% of the annual mass of plants with soil and growth medium imported to Norway each year. Over 34 000 vascular plant individuals have been evaluated, and 35 invasive, 4 doorknocker, and 24 potential invasive species have been detected. Among the material from soil samples and light traps set out at import localities, we have evaluated almost 175 000 invertebrates (excluding mites and springtails) which include 28 invasive and 37 doorknocker species. A portion of the species detected are neither known to be native in Norway nor have they been evaluated for the current version of the Norwegian Invasive Species List. We have further evaluated divided this group of species into putative native species that have likely gone previously undetected in Norway, and potential invasive species that should be sent to the Norwegian Biodiversity Information Centre’s expert committees for further evaluation as doorknocker species in future horizon scanning exercises. Invasive species introduction rates (based on the first observation of an invasive/doorknocker species during the program) have typically been below 5 plant species and 10 insect species each year, with no clear positive or negative trends during the project period. However, these rates were clearly linked to sampling effort for both groups, which indicates that any interpretation of introduction trends must take sampling effort into account in order to draw robust conclusions. Introduction pressure for individual species was low for the majority of invasive and doorknocker species, regardless of their risk categories. Exceptions to this pattern were the plants Conyza canadensis (HI) occurring in 9% av soil samples with 2.7 seeds/L soil) and Epilobium ciliatum subsp. ciliatum (SE) (occurring in 14% of soil samples with >4 seeds/L soil), and the beetle Carpelimus zealandicus (PH) (occurring in 15% of soil samples with >35 individuals/L soil). We have identified several potential synergies between the “Monitoring the introduction pathway of imported horticultural plants” program, other monitoring programs, and the existing structure for managing invasive species in Norway that can be further developed in the future. We recommend establishing an improved database structure and visualization platform to ensure effective information flow from the project, so data is readily available to inform horizon scanning and further risk assessments of species on the national invasive species list. With formal routines to combine data from this project, the “Early detection of invasive species” project, and national monitoring programs for plants and insects, it is possible to identify species that are early in the biological invasion process and further inform prioritizing of species for eradication and control measures. A pilot project using metabarcoding to identify insects has shown that when combined with data from the National insect monitoring program, we have the possibility to monitor not just the import of invasive species, but also the import of foreign insect haplotypes and to identify resulting genetic pollution among populations of native species.

Miljødirektoratet: M-2656|2023