It’s supposed to be getting better tomorrow, but the Spring so far has been slow and suppressed by easterlies. Even so, the last couple of nights have been good for the garden MV: numbers of red chestnut, early grey and engrailed are up and small quaker is having a bumper year. Nothing outstanding: A cristata, streamer and lead-coloured drab the pick of the bunch.
Bumblebee queens have been very busy foraging this week. What has become apparent is that numbers on my bee-friendly patch (the surrounding fields are a desert) are generally healthy – B. pratorum, lucorum, terrestris and hypnorum are all numerous. B pascuorum and hortorum always seem to be a couple of weeks later than the others. However, what is very clear is that B lapidarius, the large red-tailed, has had a catastrophic couple of years. It used to be the commonest of the early bees, but I haven’t seen one yet this year. Anyone else noticed an absence?
Incidentally, what is the general opinion about MV bulbs? Years ago I was taught that the moth catch decreases with the age of the bulb, but recently I spoke to an equipment dealer who was adamant that age makes no difference. Any thoughts?
I don’t know my bees that well but have an interest. I have less Queen bumbles at home this year than previous years. Last year was good to very good with lots of different species so I have been surprised as to how few there are here this year. However I have noted a lack of red tailed this year. Like you I am surrounded by arable land almost devoid of life.
Regarding mv lights I have heard that the catch falls off but not sure anyone believes it. I use my bulbs until they no longer work and for me, not a frequent trapper I have lost one bulb since 2003. If this was my oldest bulb that blew it was more than 10 years old at the time. Keith
Been a slow spring everywhere I feel. Will report on my findings once I have some spare time.
I’ve seen a few Red-tailed bumblebees here, and generally low numbers of the other species. Think a lot are only now waking up! Ditto with butterflies.
On mv bulbs, I do think they fade over time. I was running one which was a number of years old and the catch seemed to be poorer than it should have been on warm nights. Changed to a new bulb and it was much brighter and I had a better catch. It is certainly the case with actinic lights as well.
I’ve noticed a lack of B. lapidarius this year and also far fewer hypnorum which has been abundant here. Commoner than terrestris last year. I also get B. jonellus and had one in the trap a few days ago. hortorum is scarce here as a rule. MV bulbs certainly fade. When you change an old bulb for a new one the difference is obvious. It stands to reason that the catch will be lower since the light will not reach out so far for an impact.