Hi all
The use of imidacloprid has been studied for at least 20 years. Many dire predictions have been made and most have not occurred. Here VA Krischik predicts the impact of imid on ladybugs, possibly leading to increased pest populations. The second study shows no decline in overall ladybug populations in Michigan although there is a change in the species makeup of that population due to exotics. Needless to say, following the so-called "precautionary principle", we should have been moved to act by Krischik’s admonitions, and we would never have known that ladybugs would be thriving 15 years later despite the steady increase of the use of neonics.

1999
> Our study confirms the potential for systemic imidacloprid to have nontarget effects on the behavior and fitness of a common predator, C. maculata [spotted lady beetle]. Widespread use of imidacloprid in many urban systems may reduce the general mobility and number of C. maculata present in these systems. These effects could in turn increase pest populations by reducing or eliminating predation by the commonly found C. maculata.  

— Smith, S. F., & Krischik, V. A. (1999). Effects of systemic imidacloprid on Coleomegilla maculata (Coleoptera: Coccinellidae). Environmental Entomology, 28(6), 1189-1195.

2013
> We examined a 24-year dataset of coccinellid [lady beetles] communities in nine habitats in southwestern Michigan for changes in community function in response to invasion. Specifically we analyzed their temporal population dynamics and species diversity, and we modeled the community’s potential to suppress pests. Our results indicated that although the composition of the coccinellid community in southwestern Michigan has changed dramatically in the past several decades, its function has remained relatively unchanged in both agricultural and natural habitats.  

— Bahlai, C. A., Colunga-Garcia, M., Gage, S. H., & Landis, D. A. (2013). Long-Term Functional Dynamics of an Aphidophagous Coccinellid Community Remain Unchanged despite Repeated Invasions.

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