In a rush to understand why as much as half of certain bee populations are dying off, scientists at the University of Pittsburgh have been examining the relationship between flowers with high levels of nickel and aluminum and the behavior of the bumblebees that forage off them.

The results, published in Environmental Pollution, are telling.

By manipulating the nectar with the metals, researchers found that while the presence of aluminum did not have an obvious affect, the flowers containing nickel received fewer and shorter visits. However, because these visits were not stopped alogether, scientists to believe that the bees were still likely consuming the potentially toxic element, perhaps after being desensitized to it.

Furthermore, while the study's authors are not sure why the bees didn't seem to mind the flowers with higher concentrations of aluminum, they believe the behavior may be based in the fact that, according to PhD candidate and report co-author George Meindl, "past studies show that concentrations of aluminum found throughout blooms tend to be higher than concentrations of nickel." This, Meindl said, could render the bees more tolerant or even immune to it.

As the study's lead investigator, Tia-Lynn Ashman, explained in an article published on the school's site, fallout due to overexposure of nickel includes death, taste perception, agility and working memory.

Fortunately, there are ways to effectively remove said contaminents from soil, namely through a method called phytoremediation - the practice of growing metal-accumulating plants on polluted soil in order to suck the metals from the ground.

Such an approach, Ashman warns, ought to be considered carefully due to the study's findings that the bees will continue to forage on plants with high levels of potentially toxic metals. More research, she suggests, should be done in order to determine what plants are ecologically safe and will not pose a threat to pollinating animals.