For four days each February, birdwatchers of every skill level can participate in a global event for the love and wellbeing of birds.
Join us October 14th through November 18th (one day per week) for Session II
With all of the wonderful apps available, it is still a good idea to have a shelf of guides to call on. We love paging through them while planning our next exploration, exploring their beautiful illustrations, and carrying our favorites with us for quick reference.
BRDC recently hosted a Primitive Technology course as part of Galax Middle School Enrichment Week. The students were engaged with a variety of hands-on activities that connected them to skills used by early American Indians and materials found in their backyards.
"Over the last half a billion years, there have been five mass extinctions, when the diversity of life on earth suddenly and dramatically contracted. Scientists around the world are currently monitoring the sixth extinction, predicted to be the most devastating extinction event since the asteroid impact that wiped out the dinosaurs."
The plume moths, Pterophoridae, include many species that can't be identified either in the field or from photos. Fortunately there are a few exceptions in our area. This moth is maybe an inch from wingtip to wingtip. Its name, Platyptilia carduidactylus, is longer than its wingspan. Its English name, Artichoke Plume Moth, indicates one of tis host plants, but the caterpillars also utilize thistles, much more common than the garden vegetable in my neck of the woods.
In the Central Virginia Blue Ridge exists a phenomenal ecosystem, one that was probably shaped by raging braided mountain streams during the last iceage. It contains many disjunct species. In fact, over 90 species that are well outside their typical range have been documented here. It’s an odd mix of coastal plain, Appalachian and northern plants and animals. While several rare and endangered species exist here, today we focused on a well known Blue Ridge phenomenon: Salamanders.
Late October produced several interesting critters that were obviously looking for juicy meals. The first photo is a wheel bug,
Arilus cristatus
.
The second one was a small spider, much enlarged in the photo. It looked and acted like a crab spider and, when I intercepted it, was closing in on a moth half again its size.
On May 11 a blue grosbeak showed up at the house in Woodlawn. Because they aren't common here on the plateau, my wife and I enjoyed seeing it. They were plentiful during summers in Fayetteville, NC, where we lived for 30+ years. Seeing one here and adding it to our yard list was a treat.
While on one of my daily nature walks I looked down and spotted one of the true beauties of the woods, a red eft (see photo). They wander around, especially after rains and are very slow-moving and unafraid. Of course there is a reason for this- they are protected by a very potent poison, tetrodotoxin. You cannot be poisoned by handling the young newt, but if you eat it your nerve cells will have some severe problems. The bright orange/red coloration of red efts, which are juvenile stages of the red-spotted newt, clearly warns potential predators to leave them alone. As the red efts mature into adults, they become more greenish-yellow (see second photo). The adults return to the water where the gilled larvae started life and spend the rest of their lives there. This "reverse" life history (embryos, gilled larvae and adults are aquatic, but juveniles are terrestrial) is in contrast to typical amphibians, where only the embryos and larvae are aquatic. While there is much about this process that is unclear, it does seem likely that such an alternation of generations between habitats is probably a means of minimizing competition for limited food resources. One strange thing is that not all populations of newts have an eft stage, perhaps due to unsuitability of land habitats or less competition for food in the water. A similar phenomenon may cause retention of gills in some populations of tiger salamanders (leading to presence of aquatic, reproductively adult axolotls that resemble gilled larvae).
Another really interesting feature of red efts is that they are probably mimicked by other amphibians such as the red salamander (see photo). This latter creature is apparently tasty but may be protected by its resemblance to the very toxic red eft. Isn't it intriguing how the color red has come to be used as both a warning and an attractant, for example as the prime color for flowers used for nectar by hummingbirds, and as the color of ripe fruits? Remember also that the recognition of the color red requires that an animal has color vision, which many mammals do not. So the target predators for this red-hued message by the efts is likely to be birds.
Here we have another example of the complex interactions that govern the lives and appearance of critters- just amazing!
-Bill Dunson
Galax, VA & Englewood, FL
I came across a bald-faced hornet nest (actually a type of yellowjacket) in a tree while I was cutting brush. After most of the hornets had died from cold weather, I cut the nest open to examine the contents, and was amazed by its complex structure. There are several outer shells of paper (made from scrapings of wood), an entry hole at the bottom, and a series of shelves of combs (see my photo with a hornet sitting on the comb which is made up of hexagonal cells). There are hundreds of infertile female workers and a fertilized queen in the hive, and they defend the nest very vigorously! They are mainly predatory and feed primarily on insects.
This represents a typical Hymenopteran caste system made up mostly of infertile female workers, where the males appear only at the end of the seasonal cycle to mate with new queens which then over-winter to restart the entire life cycle the next season. So this life cycle relegates the males to the most basic aspect of pure reproduction- a bag of sperm !
The alternation of extreme activity during the Summer, with the eventual death every year of the entire hive, except for the newly fertilized recently hatched queens is incredible. The lives of these tiny automatons seems so strange to us, yet they are quite successful. The hexagonal geometry of the comb is interesting in its simplicity and efficiency. How remarkable are the lives of these highly social, but behaviorally rigid insects !
Bill Dunson
Galax, VA & Englewood, FL
