On the hike through the state land of the Sonoma
Developmental Center, I came across several interesting invertebrates. The most
interesting invertebrate to me that I saw was the tan praying mantis Stagmomantis californica. The species
was found in the garden at Dr. Lee’s residence and was about four inches
long. Out of the few thousand mantis
species that are a part of the family Mantidae, I was able to determine the
species through geographic location and photo identification. I first looked up
California stick bugs before realizing that this insect did not resemble any of
the stick bugs we have examined and then realized it was in fact a mantis. I
then looked up mantis species that would be found in California, which narrowed
the results down to just one species, Stagmomantis
californica. I compared the photos of the species S. californica online to the photos I took of the species and only
half of them related because there were a great number of S. californica photos that were green in coloration. After further
research I was able to determine that the one I had examined was just a tan
coloration of the several colors of S.
californica that exists. It was believed that this mantis only lived the
hot southern climates of the North American South West, but in the past 25
years began moving north. S. californica
can now be found in many of the states of the Pacific North West. Idaho State
University biology professor, Robert Anderson, believed that these
invertebrates have adapted to the cold environment through a series of
mutations. The mantis lays about 50-100 eggs in a protective case known as an
ootheca that allows the eggs to survive the winter before hatching sometime in
April or May. Although most bugs are not wanted in a garden, gardeners like Dr.
Lee can rejoice in the S. californica
since its diet consists of many garden pests such as aphids, scale insects or
mites. Since the mantis is apart of the superclass Hexapoda in the Phylum Arthropoda,
it also molts its exoskeleton as it grows and eventually it may get to the size
where it can eat larger insects such as grasshoppers. S. californica is a gardeners greatest ally in keeping the garden
clean and fresh.
Up at Fern Lake, I climbed roughly five meters into the reeds around the lake and discovered a pill bug. The pill bug was in the cracked dry mud in at the base of the reeds. This species is more difficult to identify because only a few species have been extensively studied. One species that it seems very likely this pill bug may have been is the arthropod, Armadillidium vulgare. According to Oscar Paris of UC Berkley, A. vulgare is one of the most abundant invertebrates of the California costal grassland. A. vulgare is an omnivore who is knoen to eat dead plant material, fungi, and dead animals. Since dead plat matter makes up the majority of their diet, it is reasonable that the organism I found was on the ground where there was a great amount of dead leaves and grasses. It is also believed that that the optimal conditions for the A. vulgare species is 65% relative humidity. The lake, therefore, seems like a great location for this invertebrate to live. What else I found interesting was that I was able to observe several aspects of the food chain within this lake environment. The sun is the source of food for the plants that are eaten by the consumer A. vulgare. This pill bug in turn is often eaten by predators such as lizards, one of which I also located and attempted to catch while in the reeds. It was a great example to see how energy can move through a food web.
In past hikes around the Sonoma County area, including hikes in Glen Ellen, I have witnessed much higher numbers of invertebrates. This made me realize the effect that the drought may be having on the invertebrate community. Many terrestrial invertebrates enjoy dark, wet habitats (such as under rocks in moist dirt) but with the extensive drought California is facing, these optimal habitats are few and far between. While searching though the base of a redwood grove, I was able find only one small spider on a tree despite looking under many rocks and locks where countless invertebrates are usually found. For this reason I believe the invertebrates that were found during this hike in the Sonoma Developmental Center must be well adapted to survive harsh, dry conditions. The numerous dead organisms that were found may have died in various ways but it is very likely that the lack of water in the current Sonoma County wood and grasslands could be a major factor in invertebrate species survival.
References
Descriptions and
articles about Stagmomantis californica - Encyclopedia of Life. (n.d.).
Paris, O. (1963).
The ecology of armadillidium vulgare (isopoda: Oniscoidea) in california
grassland: Oood, enemies, and weather. Ecological Monographs, 33(1), 1-22.
Praying mantises
trekking their way north into Idaho. (1997, August 31).
Spencer, J.
(1954). The absorption of water by woodlice. Journal of Experimental Biology,
31(4), 491
