September 21 Program Review

The World of … Lichens

Manuela Dal Forno, PhD, presented an entire introductory course on lichens. Lichens are complex symbiotic units formed by a main fungal partner, a green algal and/or a cyanobacterial partner, along with a diverse community of microorganisms.  They represent an important biological group present in most terrestrial ecosystems, with key functions such as colonizers, food source, nitrogen fixers, among many others. During the Zoom recording of her program, you will learn more about lichens in general – what they are, why they are important and how to detect important characteristics to identify them in the field and in the lab.

Manuela Dal Forno (Manu) is a Brazilian-American researcher interested in multiple aspects of the lichen symbiosis. She earned her PhD in Environmental Sciences and Public Policy at George Mason University in Virginia and later was awarded two postdoctoral fellowships to work at the Botany Department at the Smithsonian National Museum of Natural History. She joined the Botanical Research Institute (BRIT) in 2019. Her research has particularly focused on the discovery of new species, especially in the Tropics, and how they are related to one another.

View the recording here.

Some resources for those wanting to learn more and explore a gallery of lichens.

Lichens of North America (book) and website
http://www.sharnoffphotos.com/lichen_info/index.html
 
iNaturalist guides and observations
www.inaturalist.org/guides
 
US Forest Service
https://gis.nacse.org/lichenair/index.php
 
Ways of Enlichenment
https://www.waysofenlichenment.net/

August 14 Program Review

An Evening at SWNP – Looking for Arachnids, by Michael Smith

The evening of August 14th was focused on discovering and understanding spiders and their kin, under the guidance of Meghan Cassidy. She is a naturalist, photographer, and a strong advocate of everything in the class Arachnida. Those animals, the arachnids, include spiders, harvestmen, scorpions, ticks, and a few others, many of whom are misunderstood and sometimes feared. There is much to love about arachnids, though, and the walk on the 14th showed it.

Meghan brought a few examples to get us started, including a wolf spider, yellow garden spider, and a solifuge. During the discussion of those critters, a family discovered our little group and joined for a while. Their pre-adolescent boy promptly found a striped bark scorpion and brought it to us. It had just molted and was bright, soft and vulnerable. An interesting discovery was that, while scorpions show up as fluorescent yellow-green under a black light, this one did not. Perhaps there is some change in the chitin after it hardens that is necessary in order to fluoresce under black light.

About a dozen participants came together before we started the walk. Many of them were easily pulled into a genuine fascination with the little things of this world. For them, spiders are no less worthy of study – and of admiration and respect – than any other wildlife.

I tentatively place myself in that group, despite my continuing tactile defensiveness of webs or what feels like clutching, unpredictable contact of spider-on-skin. I can admire the symmetry and patterns of webs and be fascinated with the sparkling way that sunlight can reflect off the silken strands. I am captivated by the pretty patterns of yellow garden spiders or green lynxes, and wonder at the strange, crab-like, thorny forms of spiny-backed orb-weavers. It’s the grasping, tactile contact with a bigger spider that I struggle with. 

The admiration and wonder are stronger than the crawling residue of fear. I joined the ranks of the other naturalists, searching the vegetation alongside the trail, capturing a small species of lynx spider to ask Meghan to identify, and listening to the give-and-take of discussion as she shared her extensive knowledge of these arachnids and their natural history. We found leaves folded around silken “sleeping sacs” that some spiders use for a daytime refuge, and some of them contained shed skins of growing spiders.

It was such a positive experience, being a part of a group whose delight was in discovering and sharing things about the natural world. Somebody would find something on the sidewalk and everyone would immediately crouch down to see it up close, photograph it, and find out what Meghan would have to say about it.

“It’s a dotted wolf spider.” Meghan explained, pointing out the pattern on its abdomen and how it lacked the chevrons that defined the rabid wolf spider (which is not really “rabid” or aggressive, just fast).

After sunset, Meghan showed us how to shine flashlights into the leaf litter and look for the greenish reflected light from the eyes of wolf spiders. At the ponds, we were able to see many long-jawed orb-weavers (the name emphasizes their jaws but once again they are not aggressive or dangerous), spinning webs over the water. In the trees, other orb-weavers were constructing their target-shaped webs. The tinier spiders wove orbs so fine that they looked like small circles of woven mist clinging to a flower stem. At the north pond, participants with black lights discovered two tiny scorpions. Despite being babies, they fluoresced green in the black lights; otherwise we never would have found them.

As the evening was wrapping up around 10:00pm, I walked ahead a little and watched the approaching group, now visible as a half-dozen flashlight beams shooting out of the tree canopy at shifting angles like some luminous beast of the woods. These were my kind of folks, people who would stay past the designated time and never give it a moment’s thought, lost in discovery and wonder.

July 20 Program Review

Past Climate: Putting the Puzzle Together

Angela Kline-Osen, PhD discussed how scientists use geology, paleontology, biology, and models to help determine possible climatic conditions of the past. Her focus was on Texas, particularly the DFW region, but she also expands a bit about the Permian-Triassic period (about 250 million years ago) as that is where much of her research has been concentrated.

Dr. Osen is a Professor at Tarrant County College where she regularly teaches Earth Science and Oceanography. She has also served as Field Camp Coordinator for Geology Field Camp and taught Earth Systems as well as Historical Geology at the University of Texas at Arlington. She received her PhD in Earth and Environmental Science and from the University of Texas at Arlington where her research concentration was on Paleoclimate and Paleoceanography. She also has her Bachelor of Science in Geology through UTA. During the summer, she assists with fossil prep at the Heard Museum. Previously, she had volunteered as a dig crew member at the Arlington Archosaur Site. Dr. Osen’s discussion of the processes and results of that dig got a lot of questions (and answers).  To see the photos and hear the discussion, you can view the recorded Zoom program.

A couple of reference tips from Dr. Osen – a wonderful interactive map of Texas geology – https://txpub.usgs.gov/txgeology/ and a free smartphone app Dr. Osen recommended – Rockd from the University of Wisconsin-Madison.

June 18 Program Review

Bats of the Area and How to Find Them

Local bat enthusiasts Ellen Ravkind and Anne Alderfer along with bat expert Kate Rugroden from the Bat World Sanctuary provided our program, held at the amphitheater, overlooking the south pond.  Kate talked about the bats in this area and the role the sanctuary plays in education and rehabilitation. Ellen and Anne demonstrated the use of the echo location devices from Wildlife Acoustics (Echo Meter Touch 2).

We began to see bats flying overhead during Kate’s talk – too fast for anyone to ID.  But once Anne and Ellen turned on their echo location systems, we were able to count them and find out which ones were there.  The recap is thanks to Anne Alderfer.  The results include a “test sample” Anne took at SWNP on June 17th. 

  • Seminole (23 recordings–the most prominent species)
  • The following have 1-3 recordings and are found commonly in our area: Evening, Tri-colored, Eastern Red, Mexican, Southern Yellow, and Hoary.
  • These three were identified as possible: Big Brown, Silver Hair and Cave Myotis.
  • Not normally found in our area: Western Yellow.

Kate Rugroden is Director of Special Projects for the Bat World Sanctuary and is a licensed wildlife rehabilitator, specializing in bats, raccoons, and opossums. To learn more www.batworld.org and www.bwmidcities-batworld.org.
Dr. Ellen Ravkind is the Naturalist Manager/Environmental Educator at River Legacy Foundation/River Legacy Living Science Center. Anne Alderfer is a volunteer at River Legacy Park and a Master Naturalist.  She is involved in innumerable nature activities in this area.