The folks who make them call them systemic insecticides--a rose by any other name is....... Whether it is better than what we've used in the past is tough to assess since so much change has occurred in habitat conditions for bees and all the complex interactions, especially in the top honey producing states such as North Dakota. The region has seen sweeping change in the past decade that range from the loss of large acreage of conservation lands (e.g., Conservation Reserve Programs [CRP]) to an even greater reduction in the diversity of crops that are grown here. The regional climate cycles between periods of severe drought to periods of severe deluge; climate cycles, although seemingly bad, are the primary reason the soils are rich because there has been little leaching of soil nutrients. The interaction of climate and rich mineral soils is the main reason the region is so productive of crops, wildlife, and honeybees. Over the past couple of decades, climate has been generally favorable to crops and bees (still in mostly a wet phase of the cycle) but there have been sweeping changes in crop diversity and habitat availability for bees due to higher crop returns that encouraged conversion of conservation lands to agricultural production, even on less productive soils. When I first came to North Dakota about 25 years ago, crops were fairly diverse, CRP and other conservation lands were far more abundant, and there was less competition for flowers because there were fewer bees and more favorable and abundant habitat. Today, we mostly grow corn and soybeans (these crops were pretty much absent here 25 years ago, especially corn), we've lost most of the CRP acreage, and our bees have far more competition for flowers because our hive numbers have about doubled. As a consequence, there are fewer flowers available and the reduced diversity in crops has resulted in fewer blooming periods for pollinators. Historically, the mixture of conservation lands (pastoral too) and crops once provided fairly long periods when flowers were available to provide nectar and pollen. Today, with fewer crops, we have more dearths when little to no nectar and pollen available but we also have periods of extremely high nectar flow when weather conditions complement a particular crop or other important plants to bees--sort of a rabbit-gas-type trajectory. As tough as this is on beekeepers and honeybees, native bees are even more vulnerable when land use change results in periods of dearth when little or no suitable flowers are available because many don't store food like honeybees. Consequently, we feed more (syrup and pollen sub) than in the past to get our bees strong enough to make a profitable return in honey during periods of high flow (we generally do the same thing for pollination). Our landscape used to provide for the needs of honeybees without any help from beekeepers; a clear sign that today's landscape doesn't provide a sustainable habitat for bees--that's pretty scary. As a result, our bees will and do forage on plants that offer poor or no nutrition because that's what they have available and today's agricultural crops are not just less diverse and they form a proportionately larger area of habitat for our bees than in past decades. This does lots of things but I think a couple are profound: 1) Bee diets are less diverse (research shows that bees consume pollen from a greater variety of plants, they are healthier (e.g., improved immune systems) [pollen is their source of protein and different plant species have different amino acid composition in the protein so consuming pollen from more plant species increases the chance that they will get the diet they require) and 2) the proportionate exposure to crops is higher than in the past and the way the systemic insecticides work is much different than insecticides used in the past. From my understanding, the dose an insect pest gets from a plant grown from treated seeds is a very low dose and we don't understand all the mechanisms of how that low dose may effect bees. Maybe it's nothing to worry about, maybe it builds up in the hive (chronic exposure) that has a negative influence on the hive over time, or maybe influences (or not) the bees in ways we don't yet understand. No doubt that they kill insects; that's what they were designed to do and they work well. Maybe, even though some of the earlier insecticides, as bad as they are, weren't as hard on bees in the long haul because they were more acute, killed the bees outright so not as much insecticide got in the hive--I don't know. I do know there are lots of unanswered questions that need to be answered before we can make informed decisions to keep pollinators healthy and functioning for healthy crops and ecosystems. This is long-winded but I think we all need to think about the larger picture and how all the pieces fit together. The link I provided the other day talked to the situation in Europe and how the 3 systemic insecticides they banned resulted in healthier bee populations. There have been a number of peer-reviewed papers published that support the reasoning of the recovery in the link; I don't doubt the findings but I do suspect other factors were also important--it's a very complex world out there! I believe this is the point we need to keep in mind for context as we consider the reports such as the one in this thread. All the insults our bees receive today (pesticides from the agricultural, and other industries), chemicals and other pesticides we use in the hives, habitat loss and floral diversity, and many more) act in synergy to influence the health of our bees; I believe this is the reason it is so hard to document cause-and-effect with neonics and why it divides our views so much on causes and solutions.
