As we resume our hand weeding of jump-seed follow up along the edge of our public road, a couple of observations that are becoming more obvious as we continue. The strips that have been previously sprayed with Round-up (glyphosate) the regrowth is vigorous and lankier. Also there is a distinct absence of fungi’s and worms. Further beyond, next to the public road and where Round-up has not been sprayed there are frogs and native water plants thriving.
Photo from the Independent UK.
Glyphosate (GLY) is a herbicide that is widely used in agriculture and land-care for
weed control. Although reports about the impact of GLY in snails,
crustaceans and amphibians exist, few studies have investigated its sublethal effects in non target organisms such as the honeybee (Apis mellifera), the main pollen vector in commercial crops. Here we tested
whether exposure to three sublethal concentrations of GLY (2.5, 5 and 10mg, corresponding to 0.125,0.250 and 0.500 g per
animal) affects the homeward flight path of honeybees in an open
field. We performed an experiment in which forager honeybees were
trained to an artificial feeder, and then captured, fed with sugar
solution containing traces of GLYand released from a novel site either
once or twice. Their homeward trajectories were tracked using
harmonic radar technology. We found that honeybees that had been
fed with solution containing 10 mg l−1 GLY spent more time
performing homeward flights than control bees or bees treated with
lower concentrations. They also performed more indirect homing
flights. Moreover, the proportion of direct homeward flights performed
after a second release from the same site increased in control bees
but not in treated bees. These results suggest that, in honeybees,
exposure to levels of GLY commonly found in agricultural settings
impairs the cognitive capacities needed to retrieve and integrate
spatial information for a successful return to the hive. Therefore,
honeybee navigation is affected by ingesting traces of the most widely
used herbicide worldwide, with potential long-term negative
consequences for colony foraging success.
KEY WORDS: Apis mellifera, Glyphosate, Sublethal
Read more at The Journal of Experimental Biology.
In other words the wide spread use we are now seeing with this herbicide and probably many others are a major factor in the alarming decline of our bee population.
Photo by Rodney Weidland taken here . A honey eater enjoying a coral tree flower during the winter flowering season when there are few native flowering trees.