Northland Nature: Autumn insects continue to be activeSeptember, in similar fashion to the previous three months, was also warmer than normal. We did experience a cooling trend and after days in the 80s during the first week, we never saw that reading again.
September, in similar fashion to the previous three months, was also warmer than normal. We did experience a cooling trend and after days in the 80s during the first week, we never saw that reading again.
But nights and early mornings were not as chilly as we often get during this month. We recorded temperatures in the upper 30s a couple of times and though we did have frosts, none were heavy and killing.
During the waning days of the month, we witnessed some great colors of reds and yellows in the trees, plenty of ripe apples and acorns and, just a few days ago, I noticed that the rose hips had reached maturity as well.
Some trees, notably the hawthorns, are holding a crop of fruits on branches that are largely devoid of leaves. This tree is usually the first of our arboreal plants to drop its leaves in the developing autumn. Soon many others will take this same route after we enjoy their colorful foliage shows.
Migration is underway with many birds whether they are raptors, water birds or songbirds. Frogs and snakes sense the cool air and are moving towards wintering sites as well. Small mammals continue their preparations by storing food and building a den.
And then there are the insects.
I have been watching the insects of autumn: the late-season ones that are still active during these last few weeks. When it comes to dealing with winter, the choices are basically four for the Northland wildlife.
Some migrate, going to another place where the cold is not as intense. Others hibernate, and sleep until spring. Lots of birds and mammals
will remain active throughout the cold times. And many will die during these shortening days after laying eggs to hatch next year.
Insects are highly diverse and, with the exception of staying active, they do all these options.
Migrant insects are not too likely, but while biking in the past week I saw two kinds, the monarch butterfly and the green darner dragonfly, that do just that. While the well-known monarchs go all the way to a mountain site in Mexico, the darners make it only to the southern states.
I have seen other butterflies, the anglewings, comma and mourning cloak, that hibernate while the white cabbage and the yellow sulphur will succumb in the coming frosts.
Cold will also prove to be the demise of the small red Meadowhawk dragonfly that still zips through the yards, roadsides, fields and swamps in search of mates and meals.
Also while biking, I watched as numerous grasshoppers came onto the trail, joined by their cousins, the locusts.
Grasshoppers, so common now, will die in coming weeks. They need to deposit their eggs underground at this time. It is interesting to see how they try to lay eggs in the pavement of the trail.
Crickets of a couple kinds call in the grasses, as do katydids. They are using these last weeks of life to attract mates with their tunes. I hear them during all but the chilliest days and nights.
Others approach the coming cold in different ways. Hornets and yellow jackets go to apples, berries and other sweets to enjoy meals of their own after feeding the young of the colony all summer. The colony is now empty and they helped to raise the brood. Now they feed themselves.
In a similar manner, the bumble bees, so common in the goldenrods a few weeks ago, are nearly all gone. With both the hornets and bumble bees, it is only the queen who survives winter in hibernation; everyone else dies.
Traveling across the roads,
I see woolly bear caterpillars. They are en route to finding a hibernating site for themselves. Unlike other caterpillars, these hairy ones will go dormant for the winter in this stage under leaves — not a cocoon —
Last week at dusk, I visited a swamp. Here I watched the bats taking their insect dinners above the wetland. But in the midst of this flying, I saw another large insect, a giant water bug, rising from its aquatic home and taking wing. Apparently, they feel the cooling temperatures and decide to leave to go to a larger body of water such as a lake for the winter.
Nearly as big as a small bat, this bug is about three inches long, one inch wide and has two big anterior pinchers. And, as I saw, they also have powerful wings.
Though they are huge insects, we would probably not even notice this night flight were it not for the fact that they can and often do get distracted by our lights and buzz themselves into a fatigue and drop to the ground.
It is here that we might see them in the next morning. As the cold comes in, we will see fewer insects, but the ones active at this time continue to be very interesting to watch.
Retired teacher Larry Weber is the author of several books, including “Butterflies of the North Woods,” “Spiders of the North Woods” and “Webwood.” Contact him c/o firstname.lastname@example.org.