Martins and Drones

The purple martin is the largest member of the swallow family. These strong flying, insect-eating birds migrate to North America in the spring, and return to South America in the summer. Martins nest in gourds hanging from vines in treetops or in man-made bird houses mounted on poles. During the spring and early summer, martins rear their young. They catch great numbers of flying insects to feed their rapidly growing offspring, and the martins are feeding young birds at the same time that honey bee colonies are at the height of queen bee production. Soaring high in the sky and performing aerial acrobatics, the martins grab flying insects at will. As martins climb, dive, and sweep through honey bee drone concentration areas 20 to 80 feet in the air, they likely catch some queen bees making mating flights as well as drones.

Peace Bee Farm employs drone-breeder colonies with added drone brood frames to increase the number of drones in the drone concentration areas with valued traits. This technique, called drone saturation, is intended to lessen queen matings with feral drones. While some healthy bees are lost to martin predation, I feel like the birds actually help by eliminating weak or slow flying queens and drones. Martins surely apply selective pressure on queen bees while the queens are vulnerable outside the hive. It is evident that martins fly through drone concentration areas, because numbers of drones follow the martins back to their nest. Drones have large eyes to see queen bees making their mating flights. They seem to be attracted to the martins that fly through their drone concentration area. Following a fast moving martin, a plume of drones has no trouble keeping up with the bird as it sweeps through the sky. The drones follow the martins all the way back to their nest. Today’s photo shows a drone in close pursuit of a martin. The birds seem to pay no attention to their “comet tail” of drones.

--Richard

Martins and Drones

At Peace Bee Farm, we enjoy the purple martins for half of the year. These largest of the swallows arrive in February, nest in artificial gourds that we provide for them, rear young birds, and then leave without fanfare in July. During the six months that they occupy the farm, they entertain us daily with their song, which is almost speech, and their flight, which some describe as aerial acrobatics. Anyone who has observed these popular birds knows their ability to climb, dive, and soar can’t be matched by other birds. They can regularly be seen sweeping along the surface of lakes or soaring hundreds of feet in the air, catching insects in flight. When they approach their nest, they dive at great speed. It is not uncommon for us to see drone honey bees chasing the martins as the birds circle their nesting gourds or sweep in for a landing. Sometimes a single drone follows a martin; at times half a dozen drones will be in close pursuit. The drones, which normally pursue queen bees in their mating flights, have no trouble keeping up with the rapid, turning flight of the martins. Click on the photo and you can see a number of drones that followed the martin all the way back to the perch above their nesting gourds.

The purple martin is an insect eater and a very efficient gatherer of flying insects. It is obvious that our martins frequent the drone concentration areas and bring back drones visually focused on the zooming birds. I don’t know how many drones and queen bees are eaten by these birds along the way, but I do feel that the birds are doing their part to eliminate weak drones and queens from the mating areas. If this is the case, the martins are helping select for stronger honey bees. The martins will spend the next six months in the Amazon River basin. I wonder if their other home is a similar bee farm in the Southern Hemisphere.
--Richard