Little Bees

I was out exploring another one of the bare soil areas.  This one is odd because several feet of loose material overlay the bedrock.  The surface has a thin layer of clay, but beneath that is a mix of silt and sand.

Wet weather seeps keep this area wet during most of the winter.  Four weeks of droughty weather have allowed things to dry out completely.  The clay surface layer has even developed cracks.  My interest I this particular spot was a swarm of tiny bees rapidly criss-crossing the area.

They maintained an almost constant low level flight.  I kept watching for mating activity, but the only interaction between bees appeared to be occasional collisions that resulted in both bees tumbling to the ground.  After a split second disentanglement on the ground, they were back in the air.  If any mating occurred, it had to have been the briefest of contacts.

I don’t recall having seen this species before.  It isn’t one of those that are typically attracted to sweat and I haven’t seen it on any flowers.

Those few that landed did so in just a brief instant.  Their small size made it hard to see what they were doing.  The grass stalks in the foreground give an idea of the small size of these bees.

My best look was of a dead specimen left headless on the ground.

Some disappeared into underground burrows, so it’s possible this was a nesting area and not the site of courtship activities.  Those that landed wasted no time disappearing into the nests.  It’s also possible that they are a parasitic species and were depositing eggs in another species nest.

Others that landed did a quick run across the ground and then took off.  Maybe they were having some difficulty in relocating their nests.  I watched the activity for about 15 minutes at which time the bees disappeared.  It happened suddenly and I have no idea where they went.  I guess they either dispersed or took their swarming activities elsewhere.  It was an interesting encounter and like many others I’ve had, I’ll probably never know exactly what was going on.

Bare Ground

Blue Jay Barrens has several small areas that are so inhospitable that very little plant life is able to survive.  They are mostly the result of massive erosion that took place through many decades of poor land management practices.  This particular site is primarily rock covered by a thin layer of silt and clay.  It is excessively wet in the winter and as dry as a baked brick in summer.

Some plants manage to grow here, but their life is a struggle.  Sometimes odd rarities that can’t compete elsewhere survive in these bare spots.  I enjoy exploring these areas because the plants are spread out and easy to observe.

What appears to be soil from a distance turns out to be small gravel.  It takes a pretty tough seedling to anchor itself in this ground.

Insects and other arthropods are the real draw in these areas.  Native solitary bees find the conditions to be perfect for their underground nests.  Many of these species require bare ground as nest sites. 

I visited this site on a cool, cloudy morning, which may explain why the bees were still in their tunnels.  I saw a bee just inside the entrance to about every tunnel I checked.  I imagine they headed out to forage as soon as the weather warmed.

Little spiders were the most abundant residents this morning.  I think this is the young of one of the larger Wolf Spiders.

This is a female Thin-legged Wolf Spider, one of the Pardosa species.  These are small, fast moving spiders that are very difficult to see.  The blue egg sac carried beneath the abdomen is what gave them away. 

That blue egg sac is really something.  It gave the spider away every time, sort of like Rudolph’s nose.  It seems that a spider predator would have no trouble finding these females.  Judging by their abundance here, it might not be so bad if a few do get eaten.  When I crouched down to get some shots, there were a half dozen spiders within camera range and a lot more not far off.  If all those eggs hatch, that’ll be a lot of baby spiders.

Native Bee Swarm

The bee swarm on the barrens has come early this year.  I was out trying to determine just what the bees were trying to accomplish.  There were bees both on the ground and in the air that all seemed to be interacting in some way.

The area of activity was this steep, south facing slope of short grass and bare soil.  Hundreds of bees participated in the frenzy that covered a circular area roughly 60 feet across.  This annual event always occurs in this same location and has never been found anywhere else on the property.

Mating was a definite priority activity.  The ground was littered with small clusters of male bees competing for a female.

What I was trying to figure out was the relationship between the bees and the various holes in the ground.  Some holes were shallow excavations of less than a quarter inch deep.

Other holes were surrounded by a pile of debris that suggested a substantial underground excavation.

Still others showed no signs of any sort of digging.

The thing they all had in common was bee activity.  This bee stayed at the entrance to the hole as if it were a guard.  It would retreat inward when approached and come back to the entrance once the danger had passed.

Bees on the wing were constantly coming in low to investigate the hole, but the guard would not leave.  Mounded holes without guards were frequently entered.  What I assumed was the same visiting bee would leave the hole a couple of seconds later.

Bees behaved similarly in the unmounded holes.  I speculated that the mounded holes were for newly constructed brood chambers and the others were empty chambers from which this year’s brood emerged.  It just seemed that the entering and exiting of holes was too random for bees preparing brood chambers.  I also thought it possible that the visiting bees were all males searching for newly emerged females.  It probably requires more than an hour of casual observation to piece together the whole story.

Mating Bees

Insects spend most of their lives doing what’s necessary to produce more insects. These ground nesting bees, female to the right and male on the left, are just two of many hundreds that were busily searching out mates.

I was walking across one of the barrens when I encountered a swarm of insects rapidly criss-crossing an area about 70 feet across. They gave way as I walked into the swarm, so I sat down in the grass to see if they would come close enough for me to get a good look. They obliged and proceeded to put on a very interesting show.

Apparently, the insects in the air were males of a species of ground nesting bee that had recently emerged from their buried pupae. Occasionally, a female would work its way out of the ground and fight her way up through the matted grass. As soon as she got clear of the grass, several males would rush to her and struggle to be the lucky mate.

I kept moving the grass away, trying to get a clear shot at the struggling mass, but the group kept rolling down the hill as fast I could get them uncovered. I counted eight males wooing this female.

After a couple of minutes, the group broke apart and the female emerged with the lucky suitor. The pair did a bread-N-butter around a dead grass leaf and had to stay put a while for some photos. Several pairs formed during the short time I sat watching. It’s amazing how emerging insects can time things so perfectly. The barrens offer some perfect bare soil sites for ground nesting bee species. Managing for this type of site is one of the key activities for those trying to increase native bee populations.