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The dragonflies are swarming my neighborhood this week.

Dragonflies are fun to watch because they often return to the same perch over and over, giving you the opportunity to observe them closely.

Watch the abdomen on this one.

It has tipped its abdomen up into what is called the "obelisk posture."

It is possible that it saw my camera as a threat and this was a defensive move. On the other hand, it was a hot day and scientists have suggested the obelisk posture is a way dragonflies adjust their exposure to sunlight and keep from overheating.

Cool!

Insect swarms have been in the news this summer.

This week it was pallid-winged grasshoppers in Las Vegas (see for example, this story in LiveScience) or check out this AP video

The grasshoppers aren't the only ones.  Last week there was an article about flying ants in Britain being picked up by weather satellites (Guardian article) and in June it was supposedly ladybugs in Southern California (LA Times article) spotted on weather radar, although later reports say no one could verify which insects were actually detected.

Although these swarms can be alarming or exciting depending on your perspective, they are completely natural. Because insects may reproduce rapidly when food supplies are high and enemies are sparse, many species have the potential to build up to high numbers.

In fact, it is probably not amazing that insect blizzards happen, but that that don't happen even more often.

In a matter of days the insects either migrate away, are eaten, or come to the end of their life cycles. As quickly as they appear, they are gone again.

So for now, grasshoppers are simply having their 15 minutes of fame (or is it infamy?)

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Some plants and pollinators have unique relationships. Take the rush milkweed.

Most years our rush milkweed plants only produce one or two seed pods each.

This year, however, the plants are covered with seed pods.

Why?

To figure out, we need to go back a few weeks. At that time the plants were covered with flowers.

We also saw a lot of tarantula hawk wasps visiting the flowers.

Although they are clumsy giants, tarantula hawks are especially good at pollinating milkweeds.  Their long legs slide into the grooves in the flowers, where they collect the sticky sacs of pollen called pollinia (for more information, see BugGuide). When the wasps visit the next flower, the process is reversed, leaving the pollinia behind to pollinate the plant.

This year the tarantula hawk wasps were abundant and now the seed pods are, too, which hopefully means

soon we'll see more milkweed seeds,

which will glide away on their silky parachutes to make more rush milkweed plants, which are

good for the monarch caterpillars that eat them, and

which turn into monarch butterflies, important pollinators for many other wildflowers.

All thanks to tarantula hawks!