The Cholla Ecosystem and More about Cactus Bees

The Cactus bees finally showed up around 10:00 this morning, and I enjoyed watching them go straight to work. I was very curious to see if the little bee that curled up inside of the flower yesterday was still there, but that flower closed into a tight little bud, and I don't think I can get a view inside of it without destroying it and/or hurting the bee. Maybe it will open a little later today.

Waiting around the cactus for the bees to show up gave me an opportunity to observe the other wildlife that the cholla supports. I have come to think of the cholla as a dessert version of a coral reef! Every time I move, there are little rustling sounds as lizards run for cover under the cholla's spiky branches. There are several different spiders who have virtually covered the whole plant with webs. The cactus bees are incredibly adept at avoiding the webs. Yesterday Tim noticed a beautiful, brown dragonfly hanging out near by, and most of the cholla's magenta flowers have at least two resident ants who like to harass the bees when they visit. I mentioned yesterday that there were two types of bees that visit the cactus. Today I began to wonder if they were different subspecies of cactus bees.

One cactus bee

A second type of cactus bee? Notice it's furrier than the first one and brown.

Another view of the second cactus bee

A spider hoping for a meal

An unfortunate snail. A cactus really seems like the wrong neighborhood for such a soft creature.

I have SO many questions...where do the bees live? What do they eat when the cholla isn't in bloom? How many chollas can there possibly be in Livermore? How far do the bees fly to find them? How closely are cactus bees related to honey bees? Do cactus bees visit other types of flowers? Do my honeybees visit the cholla cactus? (I haven't seen any honeybees there). Are the two cactus bee 'subspecies' really different bees? Or is one male and the other female? Lots to discover!

OUCH!

This morning around 9:00, I went out to see if the cactus bees were up. They were not--they seem to be late risers. In fact the flowers on the cactus had not yet opened. I went home and had some breakfast, and then I went out again around 9:30. Still no bees, and for something to do while I waited for them to show up, I decided to try and take a segment of the cactus home to grow in my yard.

Now, you might be thinking, does everything this girl does have to include the possibility of getting stuck with a barbed spike? However, that did not occur to me until I dropped the cactus segment on my toe and learned that getting stuck by a cholla cactus quill is about 10 times more painful than being stung by a bee. And the quill is even harder to remove than a stinger. I had to pull really hard to get the biggest of the quills out and then my toe just gushed with blood (gush might be an exaggeration, but it was a lot more blood than I expected)! Like a bee's stinger, the cholla's quills are barbed, making them a bit of an ordeal to remove. In the final analysis, I am quite happy to study the cactus bees on the neighbor's cholla. I don't need one in my back yard!

My right baby toe after being stuck by a cactus quill.

Cactus bees and other fun stuff

I took a walk along the creek behind our house today, and on my way home, I stopped to look at an overgrown cactus with beautiful, magenta flowers. Always hoping to spot one of my bees having a good meal, I was drawn to the plant and soon noticed several frantic bees zipping around. On closer inspection, I noticed that the bees, although a similar overall size to honeybees, had a slightly flat abdomen, with pronounced white and brown stripes. And boy were they good pollinators! I watched a bee nuzzle its way into the flower's plentiful stamens and quickly pass pollen from its front legs to the huge pollen loads on its back legs. Before I knew it, the bee was onto the next flower. There was another, smaller bee on the scene, but for the most part the larger bees dominated, and I started to wonder if it was a plant-specific bee. I couldn't find it's exact match online, but I was satisfied to know that 'cactus bees' or Diadasia  (http://www.greatsunflower.org/diadasia) do exist; they are solitary bees that live in the ground and eat the pollen and nectar of cacti. Who knew? When I went back to take the pictures below, I noticed one particularly fuzzy little bee go into a flower and stay there. I confess that I bugged her a little--I wanted to know what she was up to--and I was rewarded with a very sweet picture of her peeking out. I can't help wandering what she was up to. Just taking a rest? Would she sleep there through the night? Very mysterious. 

During my search to identify the cactus bee, I ran across a fantastic story about a UK grocery chain's PR campaign, which involves hanging bee hotels across England. Here's the story: http://www.businessgreen.com/bg/news/1803494/sainsburys-doors-bee-hotels

Our bees are doing great. We combined a couple of hives because they went queenless post-swarm. They are monster hives now, and we are hoping to get a honey harvest this year...finally!