Showing posts with label insects. Show all posts
Showing posts with label insects. Show all posts

Sunday, December 20, 2009

Baby Praying Mantises

Over the summer we found several big green Praying Mantises around the Earth Discovery Center. We kept one for several days in a container to show students and visitors, and to our delight it laid a brown, styrofoam-like egg case (also known as an "ootheca" - pronounced "oo-oo-thee-ka") on the lid. We planned to put the egg case outside, but instead it got pushed to the back of the reception desk and forgotten about. One day at the end of November we were sitting at the desk and noticed a tiny yellow creature scampering across the phone - the egg case had hatched early due to the warm temperatures! We spent the rest of the afternoon rounding up the 50 or so baby mantises that had scattered all over the desk, floor, and walls.

We kept them all together in a large screened cage for their first few weeks where there was a pretty high attrition rate - so far we have six survivors. This is probably similar to their survival rate out in the wild; most of the hatchlings would fall prey to larger insects.

Here are the six survivors, now living in vials with a foam plug on the top. We put them in the smaller containers so we could keep a closer eye on whether or not they were getting enough food. The cottonballs at the bottom are for moisture, and the smaller black dots in the containers are fruit flies for the baby mantises to eat.
Here's a close up of one of the little doobers - even at this size they have all the personality of the larger mantises. They tilt their heads and wash their legs and antennae, almost like cats.

This one is munching on a fruit fly. A mantis eats by grabbing the prey with its folded pair of front legs and then digging right in and munching on the fly once it has a good grip. As the mantises get bigger, we will switch them to larger insects like crickets.


As the mantises grow, they crawl out of their old skins, leaving an empty "molt" behind. It's amazing how you can see every detail on the empty skin, even the antennae, and the spikes on the front pair of legs. The mantis hatchlings with molt several times until they reach their adult and final molt, at which point they will have fully developed wings and will be able to fly. This process, where the young insects closely resemble the adults, is known as incomplete metamorphosis. Insects such as butterflies, beetles, and flies, which have a larval forms known as caterpillars, grubs, and maggots and form a pupa before the adult stage, go through complete metamorphosis.


Contrary to popular belief, praying mantises in our area are not endangered, and you won't go to jail if you kill one although we'd prefer that you didn't. We have three species of praying mantis in our area: the native Carolina Mantid (Stagmomantis carolina) and two introduced species, the European Praying Mantis (Mantis religiosa) and the Chinese Mantis (Tenodera aridifolia sinensis).

Our babies are of the Chinese Mantis variety - they will eventually reach between 3-5 inches in length. The adults are often brown with green stripes down the edges of the wings. Chinese Mantises were introduced into North America in the late 1800's as a source of pest control - these are usually the species shipped if you order mantis egg cases in the mail, although the release of non-native species is usually frowned upon in most areas.

The native Carolina Mantis is much smaller than the Chinese Mantis - usually around 2 inches, and is often a dusty brown in color. The European Mantis is slightly larger and often pale green in color.

Sunday, March 22, 2009

Bloodroot

In the space of a day it seemed like, the Bloodroot burst from the ground at my house! I have not found any yet at the park, but I haven't really had a chance to look in too many areas. You have to enjoy the bloodroot flowers while they're up - they don't bloom for long, although the leaves last well in to spring. The leaves have deep notches around the edges, and in my opinion are just as interesting as the flowers. Bloodroot is named for the reddish sap that oozes from the roots. It was used historically for medicinal purposes, but the sap can cause severe skin lesions and can even be lethal if too much is taken internally. The seeds of bloodroot are adapted to be spread by ants. The seeds have a fleshy area called an elaiosome. The sole purpose of the elaiosome is to entice ants into carrying the seed back to their nest, where they eat the fleshy treat, but leave the rest of the seed undamaged, and now buried in a nice fertilized ant mound, ready to grow. How awesome is that! The process of seeds being spread by ants is known as myrmecochory.

Tuesday, March 17, 2009

Carrion Beetles - Gross Stuff Warning!

White-tailed Deer love to hang out right in front of the EDC. They seem to be shedding their winter coats - we found a few clumps of deer fur along the trail!A park volunteer brought me a partial deer skeleton that he found on the other side of the reservoir. Since it still had some meat and fur on it and is a bit smelly, I put it out alongside the trail for the scavengers and decomposers to finish cleaning. The skeleton has only been there a week and already it has been discovered by carrion beetles (family Silphidae), who were working away industriously at cleaning up the remaining dried up bits of flesh from the bones. Here's a video of some of the beetles working away. There appear to be two types of carrion beetle here - all black ones, and some with orange on their heads, almost like lightening bugs. I find them fascinating, but if the thought of beetles scuttling about and munching on a dead deer grosses you out, you may not want to watch this one. Just imagine how gross it would be if they DIDN'T eat the deer though - yuck!

A Winter's Butterfly

While walking along this Monday we were greeted by the sight of a dark-colored butterfly flitting through the forest - in March! Most butterflies and moths overwinter in the chrysalis or cocoon stage. A few, such as the black-and-orange woolly bear, hibernate as caterpillars, but the Mourning Cloak overwinters as an adult butterfly, and is thus the first to emerge in the spring. Occasionally folks who bring in firewood in the wintertime are surprised when a hibernating butterfly wakes up with the indoor warmth and starts flying around their house! Mourning Cloak adults feed on tree sap more than flower nectar, while the caterpillars feed on willow species. (The photo is from wikipedia - the butterfly we saw didn't hold still long enough for me to get a picture!)