September notes

Wingin’ It

By Kate Crowley

As we reach the middle of September my attention has been captured by various events taking place in the winged world.  First there is the increase in Northern “yellow-shafted” flickers.  These members of the woodpecker family are only transitory in our particular neighborhood. Each spring we watch them as they come through, landing on the thawing ground in search of food.

Unlike the other woodpeckers, flickers prefer terrestrial fare, mainly ants.  The reverse happens in the autumn.  These birds are easy to pick out when they fly away from you, by the large white patch of feathers on their rump and their swooping flight pattern. They will land in trees and when they do, you can see their similarity to the other woodpeckers, especially in the tail braced on the trunk. Their beaks are long and sharp, but have a bit of a downward curve. This makes sense since they don’t use them to pound on wood. They will head as far south as needed to find suitably soft soil and ant colonies.

We are at the tail end of the ruby throated hummingbird migration. I still have a couple of feeders set up in case any stragglers need a boost.  I have heard from others in Duluth and even further up the shore that they are still seeing the little birds at their feeders. Laura Erickson, birder extraordinaire of Duluth, believes that the hummers got such a late start on nests this year, because of our extended winter that they we may be seeing more than usual at this time of September. 

You may have heard someone say you should bring in your hummingbird feeders in the fall so that the hummingbirds won’t be tricked into staying too long.  Not true.  These birds are moving as much as because of the shortening days as the diminishing food sources. Leaving your feeders up is just a way to provide them with some extra energy as they head south. I’ll leave mine up a couple more weeks and then give up for the year. 

What has been most on my mind, however are the bees. Maybe you saw the two part article in the Star Tribune a week ago detailing the problems facing the honeybees and their keepers (as well as us).  It is a problem that most people should be aware of by now and that is the precipitous decline in this domesticated bees numbers.  The best scientific consensus says that the bees are suffering from long term exposure to pesticides, loss of flowering habitat, and the spread of disease and parasites. 

When I say this is a problem for us, I am talking about their irreplaceable value as pollinators. Along with butterflies, these two types of insects may be responsible for “one out of every three bites of food Americans eat”.  Berries, nuts and other nutritious fruits and vegetables depend on their existence due to honey bees in particular.  And let us not forget the food that they are named for – honey. It too is in decline, naturally, as the honey bees themselves disappear. 

I have not seen any honey bees on our flowers this summer. That’s not to say they haven’t been there, though I don’t know of any bee keepers within miles of us. Bumblebees are another story.  While they have been visiting our flower beds all summer, it’s at this time of the year that I really start to notice them; clustered on the center disks of sunflowers, on the Echinacea (coneflowers) and on the multi-flowered heads of Sedum. 

For the past week I have been going out each morning and afternoon to look closely at the ones on the Sedum. For the most part they have been very lethargic, to the point of appearing paralyzed. But they are moving, ever so slowly over the clusters, poking their proboscis into the nectar tubes.  I can see some faint yellow coloring on their legs – pollen that has stuck, but none have been carrying ‘saddlebags’ of pollen on their hind legs. When I get even closer and extend a finger towards their bodies they raise one of their middle legs – a gesture that means back-off, you’re too close, and so I do, though I admit that I did pet the fuzzy back of one especially large bee.

What has surprised me was finding the bees on these flowers all day long and often first thing in the morning, which leads me to believe they are staying there all night.  Honey bees will always go back to the hive, but apparently bumblebees don’t have the same need.  It has been cold these past few days and this too can lead to lethargy.  In order to fly a bumblebee’s thorax must reach 86F. This temperature can be reached by being exposed to the sun, or by shivering, which allows the flight muscles to perform.  A grounded bee will pump their abdomen to ventilate the flight muscles - the rate of pumping increasing with the rise in temperature.

It is also possible that I am seeing bees in the last days of their lives.  Among the bumblebees, only the fertilized queen will overwinter in a subterranean nest. The following spring she will lay her eggs and create a new colony.  But as I look at these somnolent bumblebees I also wonder whether they have been affected by neonicotinoids. These are pesticides that even in low doses scramble the bees navigation systems, making them behave like drunks unable to find their way home.

I was especially disturbed to learn last spring that many garden centers, including Home Depot and Lowes were selling flowers that had been treated with neonicotinoids. This pesticide doesn’t wash off in the rain; it is incorporated into the plants tissues and remains there ready to be incorporated into the insect’s bodies that feed on them. Bayer and other manufacturers of this poison insist that the dosage is diluted in the plant and too low to kill bees directly – which could well be true, but how much is needed to seriously impair the pollinator, whether bee or butterfly?

There was enough of an outcry by gardeners and other concerned citizens last spring that Home Depot has said it would “require growers to label plants containing neonicotinoids and see if they can grow plants successfully without them.” At the very minimum I want to know if the plants I’m buying are going to be helping or hurting the insects they are meant to attract.  Hopefully, all garden centers got this message and as conscientious consumers we need to ask.