RSS

Yellow Jackets

13 Oct

yellow jacketYellow Jackets. Just those two words together evoke a visceral reaction to swat the air and sweat.

Around here everyone has had a close encounter of the third kind: actual contact. It is never pleasant.

Yellow Jackets are wasps in the genera Vespula and Dolichovespula. They are black and yellow and mean. Okay, that is anthropomorphic, what they are is protective of their hive. I know this first hand. Once I was gardening and was pulling goldenrod when I unfortunately ripped the top off of a nest. A cloud of wasps flew out of the ground and around my head, so thick my vision was blurred. I ran. I swatted. I yelled. This attracted the neighbor’s dog. He was an Irish Wolfhound. He chased me being chased by a swarm of angry wasps. It was like a cartoon.

Once I was out of range I stopped and brushed hundreds of the yellow and black ladies off my body. Amazingly they bit me only 23 times. It felt like 23 matches being touched to my skin. These ladies meant business. The signal was clear–stay away from our hive.

So of course, I crept back around to the nest to see what damage was done. A 4 foot ring 2 feet thick of wasps was circling the nest.Their wing beats could be felt like electricity in the air. Fascinating.

The life cycle of these animals is a little know secret. It goes like this: colony initiation, growth and expansion, production of reproductives, reproductive dispersal, and colony decline.

Everyone seems to know that the “queens” over-winter, but where do the rest of the wasps go here in New England. Its not a nice story if you are wasp. The queens do overwinter. They hide out in the ground, old logs, tree bark, your house. In the spring she starts a new colony since she held the sperm over the winter so she can fertilize her eggs. But she doesn’t have to. Wasps are haplodiploid. That means males develop from unfertilized eggs and are haploid (have half a genome), and females develop from fertilized eggs and are diploid (like you and me, they have half a genome from their mother and half from their father). At first though she does fertilize the eggs and gets females. She starts the nest building but then leaves it to the first offspring to finish.

Most all the members of the colony are females. They are all sisters. They all have modified ovipositers (egg layers) that are stingers. They are the builders, hunters, hive protectors (the Yellow Jack venom is only for protection they do not use it to stun their prey). There may be multiple queens in Yellow Jacket colonies. More power! These yellow and black bullet bugs might seem to be a nuisance to us, but on the flip side they are hunters. They hunt caterpillars, flies (house flies being their main prey), they also drive down fly populations by competing for garbage, dead animal wastes and rotten fruit.

Once the colony is established energy goes into producing ‘reproductive’ female and male wasps. These offspring are sent off to find mates from other colonies and start new colonies.

yellow jackets on appleAs the autumn approaches the colony no longer has a purpose. No more offspring are produced, and the ties that bind no longer feel so tight. So the individual wasps are forging for themselves.This is why you see more wasps in the fall. They seem a little more aggressive, because they are looking at that juicy food you are eating and not thinking about bringing it home to mama and the babies. And she has more time to sit on that apple and suck out the juices. Its the twilight of her life let her enjoy it, soon she will slow down and die. All but the queens, those royal ladies will hole up somewhere and start the whole thing again in 6 or 7 months. Such is the life of the Yellow Jacket.

Advertisements
 
Comments Off on Yellow Jackets

Posted by on October 13, 2015 in backyard bugs, backyard science, insects, Science

 

Tags: , , ,

Comments are closed.

 
%d bloggers like this: