The September 17, 2023, Friends of the Lakeshore Nature Preserve Fall Bird Field Trip was amazing because a rain shower the previous night had caused a group of night-migrating neotropical birds to "fall out." A "fall out" is an unusual event that is exciting for bird watchers. Hundreds of birds were migrating and suddenly they ran into rain and were forced to the ground, leaving hundreds of birds wherever they landed in the dark. The birds seen on the field trip were lucky to land at a migratory stopover in the Lakeshore Nature Preserve.
Jill Feldkamp and Roma Lenehan led the group, looking up at shadowy birds in the trees near the first oak. They proceeded along the Big Oak Trail to the Second Oak and the Biocore Prairie edge and then to the Eagle Heights Gardens. Even in these open areas, warblers were everywhere - in the little oaks and other bushes, the native plants, and even in the non-native grass near the water utility. In addition to warblers, there were many flickers and other larger birds flying around
When not looking at birds, Ingrid Jordon-Thaden, Friends Board Host, explained about autumn seed dispersal of Great St. John’s Wort as well as about Black Knot, a disease found on fruit trees. Participants enjoyed learning about these plants when not watching birds. Several UW grad and undergrad students enjoyed the birds they saw, especially several hummingbirds feeding at cannas. They said that they liked the time outside away from their books and computers.
At least 40 bird species were found. Highlights included good views of flying Redtailed Hawk, Cedar Waxwing, Northern Flicker, Rose-breasted Grosbeak and Ruby-throated Hummingbird. Eight warbler species were seen multiple times by various people including multiple Black-and-white and Palm Warblers. Many Tennessee, Nashville, and Magnolia Warblers flitted everywhere. Four Chipping Sparrows and 2 Lincoln's Sparrows were found in the Eagle Heights Gardens. A couple of very lucky people saw the Merlin, a small swift falcon, fly across the grassland, possibly looking at the many warblers.
The leaders hoped that everyone enjoyed this rare phenomenon which dramatized the abundance of our migrating birds.
Report by Roma Lenehan and Jill Feldkamp, photos by Ingrid Jordon-Thaden.
On the evening of Friday September 1st, arachnid specialist Ben Klementz led a group of 18 of us on a search for the Preserve’s many many-legged inhabitants. Ben is a PhD student in the Prashant Sharma Lab studying arachnid evolution and shared with us his deep interest in spiders, harvestmen (daddy longlegs), mites, ticks, and psuedoscorpions. What is a pseudoscorpion? To demonstrate, Ben had brought some specimens from his lab. We’d normally be able to find them out in the Preserve’s damp leaf litter, but it’s been a very dry summer. Preserved in alcohol, Ben introduced us all to the pseudoscorpion. They are pudgy little creatures with two scorpion-like pincer arms. While the pseudoscorpion does not have fangs like spiders and does not have a tail like a scorpion, it does have a venom gland located in its pincers! Fascinatingly terrifying. Though, to be fair, three of these critters could fit comfortably on your pinky nail, so they are no danger to humans. Just an important member of our native ecological community.
The first spiders we encountered were Agelenid funnel-weaver spiders in the joints of the Picnic Point entrance fence. Unlike other web-weaving spiders, funnel-weavers do not add glue to their webs. These spiders instead use their speed to dart out and grab any prey that touches their web lines. Orb weavers and sheet-web weavers, on the other hand, do use glue. Spider silk glue is a fascinating substance that acts like a non-newtonian fluid, Ben informed us. Similarly to cornstarch and water, when an insect traveling at high enough speed hits the glue, the glue acts like a solid and the insect bounces off. When an insect traveling at the right speed hits the web, the glue acts as a liquid and captures them. Different spiders use different formulations of glue that speed-select their preferred prey, while preventing fast, dangerous insects like wasps from getting stuck. Silk glue chemistry also allows for the glue to be effective in wet and humid conditions, unlike most human adhesives.
The most common orb weaver we encountered was the furrow spider, named after a furrow that runs down the top of its abdomen. We even had the opportunity to watch some of these furrow spiders building their beautiful webs. Web-building spiders use their own body proportions to precisely measure out the spacing of their web strands, allowing them to make such amazingly complex-yet-standard webs in a variety of places. It turns out that the spiders that have taken up residence behind my car’s side mirrors are also furrow spiders! How they can make webs between my mirrors and doors that withstand highway speeds mystifies me.
We also encountered a number of sheet-web spiders, which make more abstract net-like webs than the typical circular “orb” webs of their counterparts. Additionally, we spotted two harvestmen (or daddy longlegs) on the trip. These arachnids are not spiders, do not make webs, and only have one body segment. Ben was able to identify one as being a juvenile of an introduced European species. We found very few ground-dwelling arachnids like harvestmen, wandering spiders, and pseudoscorpions likely because of the dry conditions, though we did find one millipede!
As the sun set and it grew darker along the paved path up towards the Biocore Prairie, the spider webs became much easier to spot in the beams of our lights. We saw tiny intricate webs between leaves and huge multi-foot webs that were strung from sturdy ground anchors. Luckily spider size does not correlate proportionally with web size! Near the end of our trip we looped back down towards the Picnic Point entrance to look at the flowers in the rain garden and along the sumac boundary of the grass lawn at the base of Picnic Point. There we encountered a number of crab spiders! Crab spiders lie in wait on flowers to ambush unsuspecting insects. Their body shape is roughly reminiscent of a crab, which gives them their name.
On our way back out we had one more chance to observe the Agelenid funnel-weaver spiders in the gate fence before we dispersed.
Many thanks to our leader Ben Klementz for this wonderful trip! Report and photos by Will Vuyk.
An Introduction to the Lovely Mosses and Other Bryophytes of the UW Lakeshore Nature Preserve 27 August 2023
UW Department of Botany doctoral candidate Brandon Corder (firstname.lastname@example.org) attracted 26 participants for this fascinating walk. As Brandon’s research is now focused on the relationship of orchids with fungi, Masters student Nkosi Evans, who is actively studying mosses, assisted him. After introductions by Hosts Will Vuyk and Doris Dubielzig at the Picnic Point entrance kiosk, we walked to a shady, wooded spot where Brandon pointed out moss growing on the bark base of a white oak tree. After looking carefully at mosses growing on the logs lying on the ground around us, Brandon explained that mosses are primitive plants that have neither flowers nor seeds.
Moss ecology causes different species to occur in layers on logs and at different heights on tree trunks.
They are difficult to identify, because
Consequently, genetic analysis is now used to identify moss species.
Brandon pointed out the glossy green seductive entodon (Entodon seductrix). The less shiny, filmier, Leskea grows on higher, drier parts of tree trunks.
On the ground below a maple tree in Caretaker’s Woods, Brandon showed us a large patch of Anomodon that exhibited the moss lifecycle, which has two distinct stages. The green, leafy tissue produces the gametes – the eggs and sperm. After fertilization (the union of the egg and sperm), an elongated red capsule forms that contains the spores. After the spores scatter, they create more of the green, leafy tissue. In addition to sexual reproduction, Anomodon has asexual, vegetative reproduction.
On Frautschi Point, Brandon introduced us to fern anatomy and three kinds of ferns. Because they have vascular systems for transferring water and nutrients, ferns are generally larger than mosses. Ferns have two essential parts: 1) the leaf = “frond” and 2) the stem = “rhizome,” which is usually underground.
The Wood fern has a large leaf (“frond”) which is subdivided into leaflets (pinnae) and subunits (pinnules). On the underside of the frond are many spots or “sori” which contain the spores.
Brandon showed us a large patch of Ostrich fern, which has the sori all grouped together on a special fertile frond. He also described the Interrupted fern, that has some sterile pinnae and some fertile pinnae.
Finally, Brandon showed us a sample of liverwort. This relative of mosses usually has a flat plant body (“thallus”). Liverworts have high moisture requirements, which prevented us from seeing them in their habitat. I have seen them from a canoe on the rock wall rising above Lake Mendota’s surface, west of Raymer’s Cove,.
Thank you, Brandon Corder, for your thoughtful preparations and clear explanations.
Report by Doris Dubielzig, photos from Mary Prior, Doris Dubielzig, and Will Vuyk