[MAIPC] steep decline in pollinators this summer?

[Stephen Hiltner]

This may not be exactly on topic, but I'd like to check in with the group
about others' observations of pollinators this summer. My observations are
very local, in Princeton, NJ, but I have paid pretty close attention to
pollinators on the classic summer wildflowers, which we have planted in
abundance, and though I noticed declines over the past two years, this year
there's been a disturbing absence. Though I've seen quite a few bumblebees,
particularly on our wild senna, the number and variety of bees and wasps is
way down. As an example, blue-winged wasps were common in previous years,
but only a few seen this year. Our clustered mountain mint was covered with
pollinators last year, with 4-6 tiger swallowtails at a time among a host
of other insects, but even the swallowtails are rare now. Boneset, usually
a magnet for insect action, is essentially empty. It's like hosting a party
and no one shows up. Strangely numerous are baldfaced hornets and European
hornets, which are often the first insects I see as I approach one of our
plantings. These are not interested in nectar, but are instead predatory on
other insects. It's not clear if they are more numerous or more obvious
given the lack of other insects. There has also been a reduction in
mosquitoes this year, mentioned by several people I've spoken with.

Others I've asked thus far have also noticed reductions in pollinators. One
suggested that homeowners are spraying more insecticides, due to the 17
year cicada brood and the lanternfly invasion. I wonder if the warm winters
mess with dormancy, and if the heavy and numerous rains are flooding out
ground nesting insects, particularly given our dense piedmont soils. Could
the cicada's myriad channels be reducing standing water that breeds
mosquitoes, but also allowing the soil to become more quickly penetrated by
rainwater, which could increase flooding of ground nesters? That hornets
are numerous could point to rain as an issue, giving an advantage to
insects that nest above ground, and leading to increasing predation on any
pollinators that survive other challenges. I have never seen a hornet catch
another insect and carry it away, however, though it may happen so fast
that it goes unnoticed.

Please let me know what you've been seeing, whether it be good news or bad.

Steve
PrincetonNatureNotes.org <http://princetonnaturenotes.org/>
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