I can find sources for you with commercial beekeepers pollinating canola crops seed-treated with neonicotinoids seeing no change in their colony survival at all.
Also, your argument would be a bit stronger if canola wasn't the crop referred to in the study the BBC post is talking about.
It's a known issue that colonies cannot survive long term on substitutes. Why this is isn't clearly known yet but the assumption is that they are missing some dietary analogue to vitamin C.
Well, the BBC article plus several studies it links to are some sources to start with. Right?
This article deals with non-honey or bumble bee species so it is not attempting to make any assertions about a neonic-honeybee health link.
The Swedish Board of Agriculture recently released a systematic review of scientific literature [0].
Bumblebees are more sensitive to subletal effects of neonicotinoids than honey bees [1][2]. There's a great variation in sociality, seasonality and living for various species of bees, which means the effects of neonicotinoids will vary between species [3][4][5].
A big issue is also that most studies only look for residue of neonicotinoids in plants or in the bee to figure out how calamitous they are. Even though many of the most used neonicotinoids have a high LD50 in bees [6], there are very few studies that look at the effects of the bees of the exposure. Instead of just looking at the individual level, more studies are needed that look at effects on sub-individual, hive and population level.
In rapeseed, there has been negative effects on the growth and reproduction of the bumblebee Bombus Terrestris linked to neonicotinoids [7][8]. And in [8] they also showed that Osmia Bicornis failed to create hives by rapeseed fields where clothianidin were used, but in average created 2.88 hives by non-treated fields.
--- [0] http://www.jordbruksverket.se/download/18.1a3130fb152332440f...
[1] Cresswell JE, Page CJ, Uygun MB, Holmbergh M, Li Y et al. (2012b) Differential sensitivity of honey bees and bumble bees to a dietary insecticide (imidacloprid). Zoology 115: 365-371.
[2] Cutler GC, Scott-Dupree CD (2014) A field study examining the effects of exposure to neonicotinoid seed-treated corn on commercial bumble bee colonies. Ecotoxicology 23: 1755-1763.
[3] Thompson HM, Hunt LV (1999) Extrapolating from honeybees to bumblebees in pesticide risk assessment. Ecotoxicology 8: 147-166.
[4] Williams NM, Crone EE, Minckley RL, Packer L, Potts SG (2010) Ecological and life-history traits predict bee species responses to environmental disturbances. Biological Conservation 143: 2280-2291.
[5] Brittain C, Potts SG (2011) The potential impacts of insecticides on the life-history traits of bees and the consequences for pollination. Basic and Applied Ecology 12: 321-331.
[6] LD50 for imidacloprid, thiamethoxam and clothianidin for the honey bee Apis Mellifera is 0.02-0.08 μg per bee. For acetamiprid and thiacloprid it's 8.1-39 μg per bee. EFSA 2012.
[7] Goulson D (2015) Neonicotinoids impact bumblebee colony fitness in the field; a reanalysis of the UK’s Food & Environment Research Agency 2012 experiment. PeerJ 3: e854.
[8] Rundlöf M, Andersson GK, Bommarco R, Fries I, Hederström V et al. (2015) Seed coating with a neonicotinoid insecticide negatively affects wild bees. Nature 521: 77-80.
