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skunk cabbage pollinators in the UK

I am located in Oregon, USA, and recently learned that most western skunk cabbage plants (our native species that is invasive in the UK) are pollinated by rove beetles (Family: Staphylinidae) in the genus Pelecomalium. I found bunches of these beetles in the flowers of skunk cabbages here in Oregon this past weekend. Would anyone be willing to look to see if these beetles are present on skunk cabbage flowers in the UK?
I really appreciate any help you could offer!
Bill Gerth



  • ButtercupdaysButtercupdays Posts: 4,531
    I put on my wellies and went to look at mine, but no sign of any beetles or other insects. It's still early days here though, there were actually a few bumble bees out, the first day I've seen more than one. The spadices ware still pale, off white, so probably not ready yet. I can't smell them myself, so no clues there!
    There were a couple of new babies to be pulled out, but I never get many, as I try to remove the spadix as soon as it has been pollinated. Don't want bother from them escaping into the wild.
  • LynLyn Posts: 23,190
    I think that plant is banned in the Uk. 
    Gardening on the wild, windy west side of Dartmoor. 

  • FairygirlFairygirl Posts: 54,754
    I had to report it last year @Lyn - because  a load of them suddenly appeared all along the edges of the little burn which is along the road, and also runs under the road. I can see them on the other side too. They've appeared in the last week or so. I don't know if anything gets done though. I have a feeling they've somehow originated in the little NT garden but I don't have any proof.  There's been some odd changes in the amount of water going  down the burn in the last couple  of years.
    They're very obvious further west from here, at Lochgoilhead - a huge stand of them where the Corbett Beinn Bheula is. Not been there for a while though. 

    If I can get down to the area they're in @b_gerth, I'll take a look. If I remember, I'll take my camera.  :)

    It's a place where beautiful isn't enough of a word....

    I live in west central Scotland - not where that photo is...
  • b_gerthb_gerth Posts: 7
    Thanks so much for checking the plants in your area, @Fairygirl!! If you happen to check occasionally over the next little while and see any insects (or don't), I'd be interested.
  • b_gerthb_gerth Posts: 7
    Thanks so much for checking plants in your area, @Buttercupdays! If you notice any insects in the flowers (or not) over the next couple weeks, I'd be really interested! I really appreciate you responding and checking on this so quickly!
  • b_gerthb_gerth Posts: 7 is a link to photos of the rove beetles that pollinate western skunk cabbage out here in western North America...

  • wild edgeswild edges Posts: 10,436
    It might be worth approaching the question differently. The plant uses a pollination strategy that is shared by other species so if you can find out what plants make the same type of smell and what insects are attracted to it in this country then that would be a start. You might have to factor in for time of year in case some insects aren't on the wing at the time of flowering. It might be worth asking on a forum that caters to insect lovers as well as plants. Try iNaturalist or similar, or maybe contact Buglife. The US rove beetle seems to be a single native species as the key pollinator for the plant so it's interesting to consider what is performing that role in other ecosystems. I think Arum species are usually pollinated by flies in the UK.
    There's over 1000 rove beetle species in the UK. It's a huge family globally. Here's the UK list if it's any help.
    If you can keep your head, while those around you are losing theirs, you may not have grasped the seriousness of the situation.
  • FairygirlFairygirl Posts: 54,754
    edited April 2023
    I took my camera when I went out but no sign of anything on the plants. I did manage to  disturb the two mallards that are often tootling around there though  ;)

    I wondered if timing and climate would have an effect on what would be around the plants @wild edges. The sun was out this morning when I went out, so more insects around than yesterday and the day before, but I don't know enough about the plants to be able to determine what would pollinate them etc. Flies makes sense though, when you consider it's an Arum. 

    It's a place where beautiful isn't enough of a word....

    I live in west central Scotland - not where that photo is...
  • b_gerthb_gerth Posts: 7
    Thanks for the pics from your adventure, @Fairygirl ! From my reading, I've learned that western skunk cabbage flowers are protogynous, which means that the female parts of the flowers develop first and then the male pollen-producing parts develop later. Out here it may be a bit warmer, so I noticed lots of pollen inside the yellow covers (spathes) around the flower stalks (spadices) when I saw the beetles, indicating the flowers had been around a while. Pollinators in your area might be waiting for the pollen to develop if it has been cool.
  • b_gerthb_gerth Posts: 7
    Thanks for the tips, @wild edges . I will try posting on other naturalist and bug-related forums too! I was just wondering if our beetles got imported to the UK with the plants and went unnoticed. I know that I've been around skunk cabbage plants a lot while hiking (though not always at this time of year) and I've never looked in the flowers to see the beetles until this year. I guess it's unlikely that the beetles got there unnoticed, but was just curious.
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