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Greengage
01-09-2016, 08:01 AM
Are honey bees responsible for the decline in native pollinators and are honey bees responsible for the spread of non native plants.

gavin
01-09-2016, 10:37 AM
Q1: Habitat loss, habitat loss, habitat loss, then maybe some other factors ..... plus the fact that some native pollinators are not in decline but are actually spreading .... probably due to climate change. It seems to be the pollinators with exacting habitat requirements that are in trouble.

Q2: Maybe a bit. However the insects pollinating Himalayan balsam round here seem to me to be bumble bees, wasps and honey bees in roughly equal numbers, and that is right beside some of my apiaries. That one plant alone must ensure that populations of all three insect types go into winter in a much healthier state that they used to.

I've even wondered whether the persistent recurrence of AFB at the site near the Isla (mentioned by Murray and DR in another thread) is helped by the sea of HB there helping swarms occupying old sites get through the winter. That is another reason for a high level of care in swarm prevention - if you let a certain proportion go as a matter of routine then they might come back to bite you next season when they spread disease back into your apiaries.

SDM
01-09-2016, 12:13 PM
I would say that Beekeepers tendencies to move bees to nectar sources like balsam is certainly contributory.
I've even known of a Beekeeper who moved the balsam to him, he would t be the only one so its surely a factor.

mbc
01-09-2016, 08:25 PM
As usual for most (all?) species, the greatest competition comes from members of the same species or very closely related species. Native honeybees have been in decline ever since imports began and they are surely part of our native pollinating fauna. Other moths, bumbles, masonry / carpenter, hover flies what have you occupy different niches and no study I've read indicates honeybees have adversely affected their populations.
As troublemaker Gav points out, habitat loss is number one, two and three on why some species are in decline.

Greengage
02-09-2016, 10:13 PM
Interesting but Habit loss on its own may not cover everything isolation, and fragmentation, inbreeding non-native species and diseases; pollution, are all contributing factors also, But lets look at Honey bees they are not native to either America or New zealand so it would be interesting to know of their impact on native species there. If the Great yellow bumblebee Bombus distinguendus was discovered off an Island in Scotland would it be a good idea to introduce hives there as both would be competing for the same flora.

greengumbo
13-09-2016, 09:25 AM
Interesting but Habit loss on its own may not cover everything isolation, and fragmentation, inbreeding non-native species and diseases; pollution, are all contributing factors also, But lets look at Honey bees they are not native to either America or New zealand so it would be interesting to know of their impact on native species there. If the Great yellow bumblebee Bombus distinguendus was discovered off an Island in Scotland would it be a good idea to introduce hives there as both would be competing for the same flora.

In Australia there is some weak evidence that honeybees outcompete native pollinators for floral resources but mainly tend to favour the non-native (mainly European) plants. I think Dave Goulson has been involved in some research on bumblebees in the UK where the suggestion was honeybees might be exploiting floral resource to the detriment of the bumbles on heather moors.

Also this by Goulson(2003): Annu. Rev. Ecol. Evol. Syst. 2003. 34:1–26 doi: 10.1146/annurev.ecolsys.34.011802.132355

Then there is this more recent paper, although a clue is in the abstract "in simplified landscapes where flower-rich habitats have been lost".

http://www.sciencedirect.com/science/article/pii/S1439179116300378

Greengage
14-09-2016, 07:57 AM
It is an interesting topic. I keep Honey bees, but when it comes to pollinating insects beekeepers seem to have hijacked a lot of the initiatives to support their own agendas. When most of the problems with honey bees would appear to be Beekeepers problems. The talk of native Honey bees in decline is always brought up, But what is native? Apis millifera millifera according to all the data I have read are not indigenous to specific countries but are a northern European bee. Ok if you have access to DNA kits you may be able to prove they are indigenous to specific areas.
This regularly gets me in trouble with Honey beekeepers. Closley related species do compete for the same food sources but the proboscis lenght in both Honey bees and Bumblebees would mean that the longer proboscis of say Bombus hortorum would prevent honey bees from accessing nectar in certain flowers. then again I have read referance to Bombus pratorum learning to rob nectar from flowers of Foxglove and Honeysuckle and Honey bees expoliting this.

SDM
14-09-2016, 08:56 PM
Greengage, you beat me to the proboscis length argument, but I'd say that alone rules out over competition from honey bees.
Did anyone see the "state of nature report" ? A pretty damning account of farming practices and completely in support of the loos of habitat argument. It covers a lot more than just honeybees. 8000 species with 1200 threatened. I haven't read the whole thing yet, but even just the headline figures are worrying.

https://www.rspb.org.uk/community/ourwork/b/biodiversity/archive/2016/09/14/a-pocket-guide-to-statistics-used-in-the-state-of-nature-2016.aspx

Greengage
14-09-2016, 10:33 PM
Ill read it later But my radar goes on alert when some of these NGOs launch reports as they have an agenda.
As Adrian Horridge said "scientific literature is scarcely read, the all-important authors’ summaries can hide the weakness of the data, the conclusions often turn out to be invalid, the titles of the papers are often misleading and textbook writers cannot know it all. Few go back and study the original design of the experiments and the data. In fact, experts are so few in the world that often there is only one research group at the cutting edge—and they have baggage and axes to grind."

fatshark
14-09-2016, 11:05 PM
Some have no baggage, no axes and are nowhere near the cutting edge ...

... just sayin'.

SDM
15-09-2016, 05:45 AM
Ill read it later But my radar goes on alert when some of these NGOs launch reports as they have an agenda.."

There's govt. organisations involved in compiling the report too, if that makes you feel better. The likes of Natural resources Wales and their Scottish,English and Irish equivalents, plus of course the RSPB and most other wildlife and conservation groups.
So I suppose they do have a combined agenda, that of conservation. Since that's one that every living thing bar those profiteering from exploiting the planet/environment shares. I don't think it skews the truth on this occasion. It's simply an audit of biodiversity, an account of its reduction and assessment of the causes and consequences of further reduction( in this case the possible collapse of the UK ecosystem).
It's a model that works especially well in Britain, the first of the industrialised nations, with a large population per square mile. We are a great early warning system for the rest of the world.
I'm stunned you think there's a lack of experts on the subject of conservation, I seem to be tripping over them lately .

Greengage
15-09-2016, 07:34 AM
An expert is a person who knows everything about something and nothing about everything else.
I myself have met a lot of beemasters lately, well they have the papers to confirm it and the media keep reminding the rest of us mortals. please bow before the beemaster.

alancooper
15-09-2016, 10:37 AM
I would say that Beekeepers tendencies to move bees to nectar sources like balsam is certainly contributory.
I've even known of a Beekeeper who moved the balsam to him.
Maybe everyone knows this but Himalayan balsalm is an invasive non-native plant pest species. It occurs mainly along river and stream banks. Since it shades out most other native species in these habitats (ie, reduces plant species diversity), surely beekeepers should not be encouraged to contribute to its long-term spread for (dubious?) short-term nectar supplies?

SDM
15-09-2016, 10:43 AM
I've had the opposite experience with the ones I've met. Both are advisors to NRW one is a retired botany professor, who retired to become a commercial Beekeeper. He advises NRW on planting matters, who's wife is an evolutionary and molecular geneticist who played a big part in the mapping of all lindigeonous welsh plants and has bees near me on several sites.
The other a retired entomology professor ( through old age) who just happened to be the only house near a patch of heather and happily has my bees on his land now. He advises nrw on biodiversity and carried out the survey in a few of their local forests( non Beekeeper)
Both seem pretty clued up full stop. I certainly learned more about bees in the first few hours of meeting the entomologist than I had in the last few years.
Both seem to manage to be capable and sociable human beings too, which to accept your point, does seem to be the exception.
Back on track sort of, tk the whole farming practices thing and loss of habitat. I agree with some of the farmers comments that progress has been made on field boundary areas etc. but it was made on the back of EU conservation subsidies. I've been told these subsidies will stop in 2020. I don't see farmers giving up 20% of their farms once they're not being paid for it.

Greengage
15-09-2016, 01:50 PM
:D ;)

The Drone Ranger
15-09-2016, 10:10 PM
If you spray a field the overspray just drifts over the field boundaries
So planting a strip of grass and nectar plants along a field boundary is not ideal
Well that's how it seems to me
After the neonic ban the crops grown round here are more diverse
It was just rape , grain, potatoes now already there are far more crops being grown
Plus there are more cows and sheep showing up in fields


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Calum
16-09-2016, 09:13 AM
Maybe everyone knows this but Himalayan balsalm is an invasive non-native plant pest species. It occurs mainly along river and stream banks. Since it shades out most other native species in these habitats (ie, reduces plant species diversity), surely beekeepers should not be encouraged to contribute to its long-term spread for (dubious?) short-term nectar supplies?

Yeah its very invasive. Here in Germany they are rife along woodland boundries. I think they fire their seeds up to 5m so spread merrily without much help. The upside for beeks is they provide an excellent late crop for that the bees can overwinter on very well. Some years you do not need any winter feed at all. So I can see a beeks motivation for leaving / planting them.
The environmental protection agency habitually has a purge to get rid of them. Their seeds are very tasty by the way - taste nutty.

Greengage
26-09-2016, 08:17 AM
I came across this from June 2016
have not found the full report nor do I speak Norwegian http://sciencenordic.com/wild-bees-lose-fight-flowers

gavin
26-09-2016, 10:13 AM
After Calum's comment I had back-up from one of the helpers at a bee workshop by the river Tay. He nibbles on young HB pods rather than seeds. Since then I've been contributing to the conservation effort by eating a few every time I see them - a few pods amongst the millions at these sites. Tasty enough but not worth travelling for.

There has been a steady if unremarkable flow from HB around here in recent weeks. A half super here and there, nucs that have readied themselves for winter. Yesterday at one site the two nucs which had remained there were piling the stuff in whereas the hives back from the heather last week were sitting quietly. Perhaps they'd been out earlier and the nucs were chancing it, getting back home shortly before the heavens opened.

At that same workshop someone said there was a conservation effort to eliminate HB on a river island I think, just to see what happened. That's about all that can be done - it is so widespread and abundant it is clearly an alien here to stay.

SDM
26-09-2016, 10:37 AM
I've seen it successfully cleared from several sites and since it can and would infest most of the uk if given the chance it's not one to give up on eradicating.

Calluna4u
26-09-2016, 03:36 PM
I've seen it successfully cleared from several sites and since it can and would infest most of the uk if given the chance it's not one to give up on eradicating.

Was talking to a lady involved in a hoped for project to clear this from the River Earn from Crieff to the sea. They considered the effort and expected expense to be very worthwhile, though I doubt the beekeepers agree.

Its not a huge bit of river and its not all full of it, but the expenditure they hoped to have approved was in the high six figures, verging on seven. This would be ANNUALLY for the foreseeable future. Apply this to the whole of Scotland and its a LOT of money. For a lot less you could deal with a truly noxious plant, Giant Hogweed, yet it grows in forests in places, especially around Perth. Once the numbers are added up the cost benefit ratio does not work out, no matter how ideologically pure an attempted eradication might be.

One patch and a decent flood later, and you have it all to do again next spring. Its here to stay.

fatshark
26-09-2016, 05:01 PM
Big effort to eradicate balsam from Monnow river catchment on Wales/England border has been very successful, though still not complete.

It might be good for late nectar, but there may well be detrimental influences on pollination more generally - for example, this quote from the invasivespeciesireland.com (http://invasivespeciesireland.com/toolkit/invasive-plant-management/terrestrial-plants/himalayan-balsam/) website which has other reasons to eradicate HB "However, recent research suggests it competes for pollinators such as bumblebees with the native riverbank species, and so reduces pollination of other plants."

madasafish
26-09-2016, 06:08 PM
HB is a natural species round here.. sorry naturalised. There are miles upon miles in fields,ditches, hedges , in valleys and moorland.. It bothers no-one, coexists with nettles, brambles and other "weeds" and does not appear to affect erosion.

Eradication is worthless. It's the wild Japanese Knotweed I worry about. I walk past a strand on my daily walks... been there 10 years and not spread - yet...A good mile and half from our house and 50 meters higher...

Greengage
26-09-2016, 07:54 PM
I hope I did not post this before.
I recently came across a research document by Alicia prowes who looked at the ecological effects of this plant on native plants her conclusions show that:

It may have some effects on native plant communities, But it cannot be said for certain that it excludes any single species. As it flowers in late summer and many people comment on it then they often overlook other plants that would have been flowering earlier in the season such as lesser celandine, Large Bitter-Cress and Marsh marigold. Etc... Also It may be the case that Hyacinths nonscripta (Bluebell), for example, provides a refuge for slugs, one of the major herbivores affecting survival of seedlings of Hymalayan Balsam (I. glandulifera) (Prowse 1998) thereby reducing the possibility of establishment of I. glandulifera in bluebell dominated area.
http://www.morrison-prowse.com/documents/alicia_prowse_phd.pdf