27.09.2015 Views

Norsk svarteliste 2007

Last ned Norsk svarteliste 2007 - Artsdatabanken

Last ned Norsk svarteliste 2007 - Artsdatabanken

SHOW MORE
SHOW LESS

Create successful ePaper yourself

Turn your PDF publications into a flip-book with our unique Google optimized e-Paper software.

Arbeidet i ekspertgruppene The work by the team of experts<br />

<strong>2007</strong> Norwegian Black List<br />

A) Fremmede arter i Norge (2466 arter)<br />

B) Stedegne arter spredt med menneskelig<br />

aktivitet i Norge (14 arter)<br />

C) Foredlete stedegne arter spredt i Norge (3 arter)<br />

Punkt B og C er ikke vurdert for karplanter. For andre<br />

grupper gir liste B og C ikke en fullstendig oversikt over<br />

stedegne og foredlete stedegne arter spredt i Norge,<br />

men er inkludert i arbeidet for å synliggjøre problemstillingene<br />

rundt begrepet fremmede arter. Det må<br />

settes i gang egne prosjekter for å gjøre disse listene mer<br />

komplette og utfyllende. Det vil også være nyttig å få en<br />

samlet oversikt over hvilke fremmede arter som er under<br />

spredning i våre naboland (”dørstokkarter”) og som<br />

med stor sannsynlighet vil kunne etablere seg i Norge.<br />

Risikovurderte fremmede arter<br />

For et utvalg av artene på oversikten er det gjennomført<br />

en vurdering av økologisk risiko, dvs. en vurdering av<br />

om den enkelte av de utvalgte fremmede artene kan<br />

ha en negativ effekt på stedegent biologisk mangfold.<br />

Begrepet stedegent biologisk mangfold inkluderer her<br />

alle nivå; stedegne genotyper, arter, habitater og økosystem.<br />

Totalt er det gjennomført en risikovurdering av<br />

217 fremmede arter. I underkant av 10 % av artene på<br />

den totale oversikten er vurdert (tabell 2). Medlemmene<br />

i ekspertgruppen har selv foretatt utvalget av artene som<br />

skulle risikovurderes og mange av de utvalgte artene<br />

er kjent for å ha negative effekter. For halvparten av artsgruppene<br />

er tilnærmet alle (80-100%) kjente fremmede<br />

arter i Norge vurdert. Risikovurderingene er gjennomført<br />

ved hjelp av et felles kriteriesett for plassering av<br />

arter i risikokategorier. Ekspertene benyttet databasen<br />

FremmedArtsBasen, som er utviklet på grunnlag av<br />

dette kriteriesettet.<br />

than 70 % of which were vascular plants (see Results<br />

for more details). One reason for this predominance of<br />

vascular plants on the list is that vascular plants have<br />

been documented in Norway for more than 150 years,<br />

based on specimens in herbaria and through the work<br />

done on ”Lid’s flora”. The trend in the vascular plant<br />

flora is constantly followed by professional and amateur<br />

botanists.<br />

The survey presented here (Appendix) is incomplete<br />

and does not cover every group of species. It must be<br />

looked upon as the start of a major, continuous task<br />

whose principal long-term objective is to close the existing<br />

gaps in knowledge regarding which alien species are<br />

found in Norway. Our knowledge is particularly poor<br />

as regards bacteria, pseudofungi, fungi and invertebrate<br />

animals. Only a small selection of bacteria, for example,<br />

has been included at this stage. Knowledge of the occurrence<br />

and distribution of invertebrate animals is on the<br />

whole poorer than for the rest of the Norwegian fauna.<br />

An updated survey of alien speciesis now includes 2483<br />

species and is divided into the following three lists (see<br />

the Appendices):<br />

A) Alien species in Norway (2466 species)<br />

B) Indigenous species spread by human activity in<br />

Norway (14 species)<br />

C) Improved indigenous species spread in Norway<br />

(3 species)<br />

B and C have not been evaluated for vascular plants,<br />

and for other groups, too, they fail to give complete<br />

coverage of such species that have spread in Norway.<br />

However, they are included to give some notion of the<br />

problems surrounding the concept of alien species. Separate<br />

projects must be started to make these lists more<br />

complete. It will also be useful to have a full survey of<br />

which alien species are spreading in our neighbouring<br />

countries (”door-knockers”) and will most likely be able<br />

to establish themselves in Norway.<br />

Risk-analysed alien species<br />

An ecological risk analysis, i.e. an evaluation of whether<br />

the species concerned may have a negative impact on<br />

indigenous biological diversity, has been carried out<br />

for a selection of species in the survey. The concept of<br />

indigenous biological diversity here includes every level:<br />

indigenous genotypes, species, habitats and ecosystems.<br />

A risk analysis has been performed for 217 alien species,<br />

which is just fewer than 10 % of the species in the total<br />

list (Table 2). Members of the team of experts have chosen<br />

the species that were to be risk analysed and many<br />

of these are known to have negative impacts. For half of<br />

64

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!