Spider Bonanza

by Eric Neubauer

If you’ve searched Texas spiders on iNaturalist lately, you’ll probably found a tremendous increase in species. This is largely due to Justin Williams (jgw_atx) in Austin, who has done a lot of work on it lately. I searched Lycosidae (wolf spiders) yesterday and there were 402 species.

I’m sharing this information in the blog, since it makes iNat a lot more useful for spider identification in Texas. This kind of community science is what makes us Master Naturalists happy, and shows how much our own work can contribute to the knowledge of the natural world.

Here are a few pictures from Justin. Click on them to see them full size. They are gorgeous. They have Creative Commons copyright.

By the way, I also got a new and interesting spider observation! This is the first time Zora pumila has been observed in Texas, according to Justin Williams. The discussion on my observation is quite interesting.

Zora pumila observed by Eric Neubauer on January 12, 2021

Feast Time for Hawks

by Eric Neubauer

Much has been written for those of us who want to attract wildlife, but sometimes luck plays a part. It turns out this is an ideal venue for hawks, validated by the hawks themselves.

Two hawks hanging out.

I planned to make my former farmland a prairie rather than a lawn because that’s what would be natural for the area. Doing nothing was a great start. While I decided how best to proceed, nature took over. All kinds of plants came up, both native and non-native. By then I knew I’d have to mow once in a while to control the growth of brush since burning wasn’t a safe option. I mowed several paths through the grass and weeds and around the house so I’d could access various parts of the yard without walking through head-high grasses and forbs. Next I started mowing in from two edges of the property before stopping and leaving the rest as cover for wildlife. This included the margin along the north edge of the property under the power line next to the road.

The hawk hunting venue

When late fall arrived I noticed how often a hawk was sitting on the power line. At first a Prairie Falcon was there on a regular basis, then an American Kestrel, Cooper’s Hawk, and Red-Tailed Hawk showed up. After a couple of months it looked like they’d finally hunted the area out, and started watching across the road instead. Today they are gone except for the American Kestrel. On the last busy day, the Cooper’s was on the power line just as it started to get light. Then a Red-tailed Hawk (I think) flew up to the transformer on the pole about 15’ from the Cooper’s, before moving down a couple of poles. Right after that an American Kestrel came along and buzzed the Cooper’s before landing on the wire midway between the other two. It wasn’t the first time I’d seen that happen. Loggerhead Shrikes are also on the wire a lot, but that’s a year round occurrence. I know hawks are also perching on my roof and using the mowed area around the house in the same way.

Here is why I think the venue worked so well;

  1. The tall grass provided cover and food for grasshoppers, small birds, and rodents. The mowed area next to it made them accessible to the hawks when the prey strayed.
  2. The wire was on the north side of my property so they could approach their prey with their shadows behind them and the prey wouldn’t be warned as a shadow passed over them.

The grasshoppers are also giving out now. The only ones left  are a very few Schistocerca americana and Melanoplus femurrubrum adults, and some Chortophaga viridifasciata nymphs. In late summer, there were hundreds of thousands of M. femurrubrum nymphs, and a plague of Biblical proportions appeared to be brewing. It appears few ever made it to adulthood, and those that did suffered heavy predation. I’m sure the little birds did their bit, but the hawks did too. Attracting birds isn’t purely for entertainment.

Flying Spiders and Other Arachnid Tales

by Eric Neubauer

Flying Spiders

A while back a friend directed me to an article suggesting that spiders use the electrical gradient in the atmosphere to become airborne. When they produce silk, it has a charge and is attracted upward. Enough silk, and they’re up and away. So, the thing that causes lightning can also be used by spiders to fly.

Sometimes the webs get caught on fencing. Image by @Donatellaloiphoto via Twenty20

After I read the article, I’ve wanted to see a flying spider. Yesterday, I was lucky and saw one go by at about 5 mph and 6 feet above the ground. I saw the spider, one of my guests saw the silk thread it was suspended by. Unfortunately it went by too quickly for either of us to  see what was at the other end of the thread.

Whether it is pure instinct or involves some thought, the spider is purposefully flying. By dropping down on the thread, the spider can land at will. I have seen what I take to be silken spider balloons lying on plants.

I’ve also wondered how those silken threads that span the tall grass on either side of the driveway got there. It would be tedious for the spider to go down, across, and up while risking the thread getting entangled along the way. They probably simply fly it across. I’ll be looking for more flying spiders.

Additional information from Sue Ann

I’m busting in on Eric’s article, because this is also one of my interests. I found on Wikipedia that this is called ballooning. Apparently lots of spiders and some other organisms do this, and yes, it’s electrical!

I’ve also read that the wolf spiderlings are blown out of their nests on these little parachutes of silk, which is how they disperse. Here’s a close-up I found. At some times of the year at our ranch, they are everywhere. I can remember getting covered by the sailing webs while driving in our utility vehicle.

From Sue Ann: this is a photo we have framed and hung on the wall. Our dog, Penney, was running through the field at sunset during the time all the spider babies are flying off. The sun is reflecting off the webs.

Are spiders disgusted by humans?

As the season winds down and the avian predators clean up the last of the grasshoppers, the mating season of Eastern Harvestmen (and women) is in full swing. Perhaps because of this they seem to be very curious.

Have you ever seen a daddy longlegs this close up? Wow! Photo by Eric.

Twice I’ve had them come to investigate while I was fussing around with something. Rabid Wolf Spiders also do this, but I figured in their case they were hoping for a meal like the swallows that appear when you’re out on a lawn tractor.

The funny thing was when I stuck my finger out to see what the Harvestmen would do with it, they turned tail and ran away immediately upon contact. It seemed as if they had the same gut reaction that some people have when they see a spider. It also suggests they have really poor eyesight and are probably as comfortable in total darkness as they are in light.

This is apparently a harvestman and a harvestwoman. (ha ha)

I later had another encounter with a harvestman. I kept my finger still as it approached. As soon as its leading foot touched me, it turned and ran. Primatephobia at its  best!

Amazing Things in Nature

by Eric Neubauer

Finding a funnel web a couple of feet off the ground is unusual, and more so when it uses a knot hole as a focal point. This shows nearly as much “intelligence” and behavioral flexibility as using something in the environment as a tool.

Funnel weaver nests are usually on the ground, above a hole

So, where does that “intelligence” reside? I can see two main conclusions: First that intelligence is no big deal after all, and second that intelligence must reside outside the physical being. However it seems logical that the expression of “intelligence” would be subject to the limitations of the physical being.

Here you see the spider peeking out of the knothole it’s used for a “hole.”

As far as intelligence residing outside the physical being, one of the unique characteristics of life is its ability to act with purpose which is something that lies outside of the laws of physics anyway.

Boopedon gracile: A Photo Essay

by Eric Neubauer

All photos copyright 2020, Eric Neubauer.

Boopedon gracile, the Prairie Boopie

Fact Sheet

• Range is south-central Great Plains into Mexico.
• 26th most commonly observed grasshopper in Texas at iNaturalist.
• Eye oval in shape, less curved in front; dark with fine tan mottling.
• Thin black stripe extends from front of eye, just over and past antenna.
• Female has vestigial wings and is flightless.
• Male has functional wings which usually extend beyond the abdomen.
• Most have black “eyebrow”, curved on top and flattened on bottom.
• Light dorsal stripes on pronotum are parallel toward front rather than pinched, then widening and fading toward back; slight pinching on males.
• Front lateral edge of pronotum usually light.
• Abdomen with black sides appears striped as segments have pale trailing edge. Black may be eroded, especially on females. Top of abdomen is pale.
• Hind femur strongly banded on male
• Outside of femur on female mostly black; back and inside may show banding.
• Hind tibia violet on at least one female; apparently tibiae not colored on instars.
• Female colors tan, green, and black.
• Male colors dark brown, black, and yellowish tan.

The habits of this species aren’t well known. Photos of male abdomen and most instars are lacking here.

More Photos

Female with a lot of green
Female with a little green
Two more examples
Female showing violet tibiae
Left: yellowish female. Right: female with longer wings
Typical males
Typical male
Light male
Youngsters

You are welcome to download this PDF of the photo essay. Click the Download link below.

Reference:

https://idtools.org/id/grasshoppers/factsheet.php?name=17690

Note: Boopedon nubilium is found in western Texas. The male is black. The typical female is mostly pale brown and somewhat similar to B. gracile.