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[00:00:00] Michael Hawk: Have you seen all of those scary headlines about massive, venomous spiders invading the eastern USA? Well, as you might imagine, those headlines are designed to drive clicks so that individuals and media can monetize their content. That’s a massive downside to the internet age. Clicks and likes are the currency, and the methods that deliver those clicks and likes are very often inauthentic or, in this case, downright misleading.

[00:00:23] So today with the help of Dr. Sarah Rose, we’re going to get to the bottom of the reality of Joro spiders. Those are the spiders behind the sensational headlines that I spoke about.

[00:00:31] You might recognize Sarah from episode 58 of Nature’s Archive, where we had a deep dive into spiders. We discussed how they make wind sails, cast nets to capture prey, how they produce their own antifreeze, and the fact that they’re A list impersonators of, of things like ants and even bird poop. Dr. Rose is the author of the spectacular field guide, Spiders of North America, from Princeton University Press, and has a Ph. D. in Restoration Ecology from The Ohio State University.

[00:00:58] I’m including that full interview as well this week, so you can catch up on the amazing world of spiders. And be sure to check out Sarah’s YouTube channel, which has lots of fun spider videos and the show notes on naturesarchive. com, which has some incredible spider photography. So this episode came about because I Patreon patrons, and we’re going to answer all of those today.

[00:01:19] And of course, Joro spiders were asked about. which is why we’re covering them, as well as a question about some incredible videos of peacock spiders who perform elaborate mating rituals consisting of dancing and drumming. So, by the way, if you want to support Nature’s Archive and jumpstart Nature’s broader mission to catalyze people to make a difference for nature, please consider becoming a patron, too.

[00:01:40] You can do this for as little as 4 a month. And I try hard to give special perks and unique content, and you can cancel at any time. I can’t stress enough how important this is for our volunteers and I to continue to make content. So, to get started, what’s up with those Joro spiders? I’ve seen headlines such as giant venomous flying spiders with four inch legs heading to the New York area, giant spiders expected to drop from the sky across the East Coast this spring, and giant spiders are invading the East Coast.

[00:02:10] This is not a drill. So those really sound scary. So I asked Sarah what the reality is, and she shared this response with me.

[00:02:18] I’m going to read the response, which she also posted on social media. So here goes. Lately, the giant flying venomous spider articles have been doing the rounds again. These are not new articles. They circulate quite regularly. They use sensational language and inaccurate information. So let’s set the record straight.

[00:02:37] If you have my book, the species appears on page 187 and she posted a screenshot on social media as well. I’ll make sure to link to that post, by the way, in the show notes. So the Latin name for the spider is Trichonephila clavata, hopefully I pronounced that right. These were accidentally introduced, at least that’s the assumption, in Georgia prior to 2014. . That means the spider has already been in the United States for over a decade and it hasn’t taken over the East Coast yet.

[00:03:06] It has slightly increased the area that it occupies, but the speed at which this is happening is not alarming or rapid. They can be transported by humans. It’s likely how they arrived in the US in the first place. There have been a few records from outside the localized area they inhabit due to this.

[00:03:23] Are they venomous? Yes. Like most spiders, the spider uses venom to neutralize its prey. There are a few venomless spiders, but the vast majority of spiders do have venom. Like most spiders, this venom is not considered to be medically significant, meaning you might have localized pain and swelling if bitten, but you would not need medical attention.

[00:03:45] And, and this is a big and, like all spiders, this spider really wants nothing to do with humans and will only bite a human as a self defense last resort. They are not out to get us and actually will feed on things that might be out to get us.

[00:04:00] Are they giant? They are quite large. Females can have a total body length of up to 30 millimeters. Some of our native spider species are of a similar size.

[00:04:11] For example, female yellow garden spiders and the female giant lichen orb weaver can have a total body length of up to 28 millimeters. For those of you not familiar with metric, that is a difference of about one 32nd of an inch. So basically the same size.

[00:04:27] And the golden silk spider, which can be found in the southeastern U. S., is larger. Females can get to 34 millimeters total body length.

[00:04:35] Do they fly? Many spiders use a technique called ballooning to disperse. Anyone who has read or seen the movie of Charlotte’s Web should be familiar with this. There’s a size limit when it comes to ballooning. Therefore, only the young spiderlings can balloon. Now, are they invasive? Well, researchers are looking at this, but at this time there is not scientific consensus showing that they are having a negative ecological impact.

[00:05:00] This is going to be a tough one as many arthropods are in peril right now. So even if changes in native species are detected in the area, it will be hard to separate those from other possible causes, such as habitat loss, global climate change, overuse of pesticide, etc. This is especially difficult if you are using something like iNaturalist for your data, as many people are posting these spiders, but are not posting their native spiders to provide complete data.

[00:05:25] Should we systematically kill them as they are not native? I cannot see any reason to promote killing them. They will eat many things we consider pests. In their native range, they have been documented preying on brown marmorated stink bugs, which are an invasive species in the United States. I also worry about recommending the public take any action, as there are similar looking native spiders.

[00:05:47] I have seen too many cases where people are proud of destroying an invasive species when in reality they just killed a native species that looked similar. Even if they are documented to be invasive, I would also point out that their impact will be minor when compared to things like the emerald ash borer or even domestic cats that are allowed to roam in the environment.

[00:06:06] I often wonder if the people promoting killing them are actually looking for an excuse to kill spiders in general than having an overall motive to protect the ecosystem. They are beautiful spiders with a gorgeous golden silk web, so stay calm and just admire them if you happen to see one. Researchers are using iNaturalist data to track them.

[00:06:25] Posting images can help out, but remember to also document your native species if you use this platform, especially other orb but you do have to wonder why this keeps making the rounds and why the headlines are so dramatic. I saw an article some time ago promoting planting milkweed for monarch butterflies.

[00:06:43] why the article is not titled, Your neighbor might be planting toxic plants in the hopes of increasing the numbers of poisonous insects.

[00:06:50] I realize many people have been taught to fear spiders. Maybe this is something we should work on as a society as they are really beneficial to us in many ways. In conclusion, please, please, please do not click the clickbait articles. The more they’re clicked, more they will continue to be posted.

[00:07:07] Please do not share them for the same reason, and please be kind to spiders.

[00:07:11] Okay, with that out of the way, on to the other questions. So, in addition to the couple of questions I had about Joro spiders, listener Laura asked, I do wonder about the mating ritual of the jumping spiders and if any other species do something as elaborate as the dancing and drumming. Moreover, the peacock jumping spider and his fan that he waves to woo the females.

[00:07:31] Do other species have anything like that as well?

[00:07:35] So Sarah replied with the following. Spider courtship is a complex business, and as spiders are diverse, there are many different forms of courtship. The peacock jumping spider has a fascinating technique where he shows off his highly colorful abdomen in a manner similar to how a peacock shows off its flashy tail feathers.

[00:07:53] These are not the only spiders with complex courtship ritual. So jumping spiders have good vision. And as such, many of their courtships often involve a visual component. Spiders also have hairs on their legs that are capable of hearing sounds, and hearing is in quotes. Spiders are capable of making sound by drumming and stridulation.

[00:08:14] Think of a spoon on a washboard. Arachnologists will often say that courtship involves singing and dancing for the jumping spiders as both techniques are used.

[00:08:21] One really interesting species to look at these behaviors in is the dimorphic jumping spider.

[00:08:27] The males of this species have two very different morphologies. Morphologies are basically that they look different. There are the gray males and the tufted males. Interestingly, the courtship dances of the two different males are also very different. As jumping spiders have good vision, researchers can create videos of the various courtship rituals and present them to the females to determine their reaction.

[00:08:51] There’s some fantastic research that has been done and is being done on these behaviors in spiders. Complex courtship methods allow the spiders to confirm that they are the same species, and for the male to determine if the female is receptive, and in many cases this allows females to pick the best or most fit males to mate with.

[00:09:08] These types of rituals are not isolated to jumping spiders. For web building spiders, the males will pluck out a song on the webs of the females. Wolf spiders use stridulation and drumming, and some use visual dances. Some males offer the females nuptial gifts, some restrain the females during mating, and there are chemical signals, often in the silk.

[00:09:30] Some spiders use touch to communicate in courtship rituals, just to name a few. When your potential mate could easily kill and eat you, there’s a benefit to getting things right.

[00:09:40] Thank you so much to Sarah for answering those questions. And without additional delay, I’ll move on to Episode 58, which was the full discussion that I had with Sarah, talking about her book, spiders in general, and her own personal pathway that got her interested in spiders in the first place.

[00:09:56] Sarah, thank you so much for making the time to talk with me today about the wonderful world of spiders.

[00:10:02] Sarah Rose: Well, thanks for having me.

[00:10:03] Michael Hawk: I always like to find out for my guests really how they got interested in the passions that they’re pursuing. So I’m wondering like, maybe even backing up more than that, where did you grow up and how did you get interested in nature in the first?

[00:10:16] Sarah Rose: I’m originally from England but my dad worked in the aircraft industry, so we moved around a lot. Almost like a military brat. I went to like 16 different schools between elementary and high school. So where did I grow up? All over the place, but the advantage to that, Because we were constantly moving.

[00:10:36] Our family didn’t do family vacations and take trips places because we were always moving. So instead what we would do is we’d do like mini trips out to local things to get to know the local flora and fauna . So when we lived in Seattle, we would take a day trip to Mount St.

[00:10:52] Hollands type of thing. And it just really got me curious and my parents really did inspire this of what’s here what’s to know about what’s here that can hurt you, that you should be looking out for? What’s interesting that’s only found here. So we did all these little exploratory trips every place that we lived, and it just gave me this real understanding of how broad and diverse and different things are in different places.

[00:11:15] Michael Hawk: I guess the positive side effect of constantly moving is lots of exposure to new habitats and new things. When did you realize though, that you were really interested in spiders, that was a outsized interest for you?

[00:11:27] Sarah Rose: So I, I’ve always loved spiders. I think they’re just really awesome. They’re engineering feats with making their webs and how they hunt and take down a lot of the things that we don’t like. And I guess I never really thought of it as a, an oversized interest or that they, I was really, some, it was something different than most people until when I was an undergraduate at the Ohio State University.

[00:11:50] I did a summer up at their Stone lab, which is on an island in Lake Erie. And I took Field Zoology there with Dr. Michael Hogarth and we had to do a field collection of various. Mainly insects, but pretty much anything that we were allowed to collect. And I just really loved looking at all the different spiders and it’s such a huge diversity of spiders right there.

[00:12:15] And he then put me in touch with Richard Bradley, who’s the author of Common Spiders of North America. And just went, if you’re that interested, maybe there’s some ways for you to learn a little bit more.

[00:12:25] Michael Hawk: So was that the point where you really recognized that maybe this was going to be your career? Spider research, spider observation publishing. I don’t even know how to describe it.

[00:12:36] Sarah Rose: No, not really. So I knew I had a passion for biology and all living things, and so I got my bachelor’s degree and then I was actually working on a bird project. Where we were going out and checking nesting success for various birds in a rural to urban gradient. And while you’re wandering around looking for bird nest, you happen to come across a lot of spiders too.

[00:12:58] And so I always had my camera with me and was photographing the spiders and actually was talking to the PI on the project about the fact that there were different spiders in the rural sites compared to the urban sites. And she was the one that pushed me, that I should go to grad school and maybe do some research on different spider communities.

[00:13:14] Michael Hawk: I’m sorry, what is pi?

[00:13:16] Sarah Rose: A primary investigator.

[00:13:18] Michael Hawk: Ah oh,

[00:13:19] Sarah Rose: So it’s usually the head scientist on a project.

[00:13:22] Michael Hawk: right. So it was that observation of of the differences that triggered. Further research and at university, maybe I’m jumping ahead a little bit. I know that you’re looking in specifically, at least from what I read in your bio, and you can correct me where I’m wrong that you’re looking at them from a perspective of how they relate from a restoration ecology standpoint.

[00:13:43] Can you tell me more about.

[00:13:44] Sarah Rose: My, PhD is actually in Restoration Ecology and I ended up working with someone that was looking at fuel loadings in the Jack Pine stands in Michigan. And so we decided to put the spider component on that. How did the spider communities change with the succession of the forest in natural succession as a way to, if we’re going in and manipulating to, to create the forest we want, are we doing it successfully?

[00:14:12] And then you can use the spider communities to work as an indicator for that because one of the problems that we have with Restoration Ecology is, We use plants as a lot of the metrics. So we go into an area, let’s say it’s been devastated by some human alteration and we want to restore habitat.

[00:14:29] We plant the plants that are supposed to be there, and then too often we use are the plants there as the metric as to whether we’ve succeeded. Well, if we’ve put the plants there, the plants are there. We need to be looking at other metrics to be sure that we’re making a complete ecosystem because just having the plants isn’t restoring the ecosystem.

[00:14:49] So the idea was if we use naturally regenerating jack pine stands, we could look at the spider communities and then we could use that to go into these artificially regenerated Jack Pine stands to see if we’re getting those same communi.

[00:15:03] Michael Hawk: That’s fascinating and I know in some past episodes of this podcast. With other guests talked about Kirkland’s warbler, which is dependent on Jack pine forest. So I’m wondering, just, I’m going out on a limb here, but in your research of the spider communities, does , Kirkland’s warbler come up in any connective way?

[00:15:21] Sarah Rose: So actually some of my sites had kurtland warblers nesting in them, so I had very restrictive access to some of my sites. But that’s actually why they’re looking at the fire loading the fuel loadings and the fire history up there. Because what we’ve done is we know that kurtland warblers like the five to 20 year old stance of jack pine.

[00:15:41] So once something gets to be 20 years old, we chop it down. We go and plow through it and we plant three to five year old Jack Pines in it to, to speed up that process of getting curtland warbler habitat, which means we’re now excluding things that use the one to four year jack pine stands and anything that lives in the 20 plus.

[00:16:01] And so that was one of the things that we were taking into consideration is when we’re doing this, when we’re manipulating the system for one specifically endangered animal, which we need to do to get their numbers back, are we potentially putting other things in per.

[00:16:17] Michael Hawk: Yeah, that’s a, something I hadn’t really thought about honestly. So in, in this case, when the Jack Pine forests are getting too old and this this effort, comes in and they’re cut down and plowed over and restarted, is that meant to replace wildfire or some other natural disturbance?

[00:16:34] Sarah Rose: So yeah it’s a fire dependent system, so they’re going in and mimicking wildfire by taking out the older trees. The other interesting thing, if you ever go onto Google Maps and you look into like the graying Michigan area is the areas that they’ve planted with Jack Pine. They do this open weave where they do like an undulating line of jack pine and then another undulating line of jack pine.

[00:16:57] So you get this very uniform pattern in these. That’s not how natural forests regenerate. When it naturally regenerates. You get these really spotty and you do get these lines of mature trees that just don’t burn when there’s a fire. So when we go in and we clear cut, we’re very much not mimicking the natural process.

[00:17:17] Michael Hawk: And from your research, how did that translate to the spider diversity and abundance in that area?

[00:17:23] Sarah Rose: So for my PhD, we did the first part, which was going in and sampling the communities in these naturally regenerating jack pine stands. Hopefully in the near future I’ll get a position with a university and then I’ll be able to do the added part, which is then going in and sampling the managed sites to see how they compare to the naturally regenerating sites.

[00:17:45] Michael Hawk: And do you feel that from your knowledge of spiders are they a better indicator species, so to speak, than maybe some other species when you’re looking to extrapolate the health of those systems?

[00:17:56] Sarah Rose: So the reason I think that spiders are a great indicator species is because they’re everywhere. You can’t go into a terrestrial system that doesn’t have spiders. They’re diverse there. There’s always gonna be a couple of hundred at least species in an area. So you’re gonna always be able to detect those changes in that slight habitat preference difference in the different spiders, what they’re utilizing, whether they need vertical structure for building their webs on whether they’re more ground dwelling to need that leaf litter.

[00:18:25] So because of all these different life strategies that they have, I think they’re a great indicator. The disadvantages, they can be time consuming to identify and going out and collecting and then identifying all the spiders does take time. But I personally think that they’re a great choice.

[00:18:42] Michael Hawk: Yeah, that’s super fascinating. I think when we get into some of the life history topics of spiders here in a few moments, that will start to become clear for listeners too as to how specialized they are and how they do fit in so many places. And actually maybe even before we get there, I know that there are lots of people, my own kids included, who are just, they have a kind of a visceral negative reaction when they see a spider.

[00:19:05] And and I’m wondering like, What is your most persuasive argument for people to help them see spiders like you see them?

[00:19:13] Sarah Rose: Well, first of all, I. Looking at them, actually taking the time to look at some of the really close up pictures. Start with the jumping spiders. That’s really gonna be the gateway spider. , a lot of them have a really cute face with some big eyes that, that sort of appeals to humans.

[00:19:28] So take a good look. Normally all people see is that thing scurrying across the floor, but when you start looking at some of these macro photos where you can see the faces and the beauty and the colors. But the thing I like to point out to people is there was a paper that came out either last year or the year before where they calculated that spiders on the entire planet consume prey That would equal in mass the entire human population in a. if you think about all the little insects that it would take to be the equivalent of the human population, they’re eating a lot of things and a lot of those things that they’re eating are things that we probably don’t want around. So things that are gonna be the biting insects that are coming to feed on us, the things that are feeding on our crops, the things that are feeding on our homes and our resources.

[00:20:22] So just from that standpoint, if you start to appreciate the fact that they’re out there doing a great service for us and have no interest in messing with us. But yeah, I think the biggest thing is start looking at those pictures. There’s some great videos that have recently been made that are a little animated videos that, that depict spiders that make them really cute, but it’s a great way to get into that.

[00:20:49] Michael Hawk: Yeah, I’ve shown my kids Lucas the Spider, which is this kind of cute animated Yeah. And they have a social media presence as well. It’s something that you can follow, know, like on YouTube I’ll link to that actually. And yeah, I, when I find a jumping spider I was so happy actually.

[00:21:03] I took my kids camping and a jumping spider jumped on my leg and it was checking me out is what it, how I interpreted it. Anyway, it was crawling around and, of looking, it looked like it was looking at me and my kids thought it was really fascinating. And so now every time we see a jumping spider, I remind them of that instance.

[00:21:20] And I hope that it resonates. Like, yeah, no reason to be fearful,

[00:21:24] Sarah Rose: So the jumping spiders are one of the few spiders with really good eyesight. So when they look like they’re looking at you, they’re looking at.

[00:21:31] Michael Hawk: Yeah, that’s cool. And I also remind them when we find spiders in the house, that they’re there for a reason. Like they must have found some other insects to eat. So it’s it’s a good thing. And you know what’s gonna happen if we get rid of the spider? What insects are gonna start to appear that maybe you like less so

[00:21:47] Sarah Rose: Yeah,

[00:21:47] Michael Hawk: spider but that hasn’t worked real well because then they turn that into it’s more of a fear based kinda kind of argument anyway.

[00:21:55] Yeah. It’s always a challenge with kids. You started to talk a little bit about how the spiders, consume a lot of things that we would consider pests. And that might be a good segue to talk about some of the diversity in the world of spiders. I feel like this is saying tell me about world history in an hour.

[00:22:14] You know, There’s so much you could talk about. Maybe we can start, I don’t know where the best place to start is, but, talking a little bit about the diversity that we see here in North America. Maybe from hunting styles or prey choices, or, I don’t know what, whatever you think is best as an entry

[00:22:29] Sarah Rose: So I actually think that’s a great way to go into what the guilds are. So the guild assignment that’s from a paper cardoso at all that I used for my PhD research to put things into different blocks to make it easier to analyze data was the first goal from that. But it’s this really nice way of saying spiders can be split just based on how they hump for their prey and how they hump for their prey is gonna tell you a little bit about what prey they’re hunting.

[00:22:57] So for the guilds, there’s four guilds that have web building. For prey capture and for guilds that there is no web for prey capture. So right there you can see there’s gonna be a difference in what they’re catching. So if you’ve got your big orb weavers with their big round web that’s suspended in the air, most likely they’re targeting flying insects for their prey.

[00:23:18] And that’s why the web is deployed in that way. Whereas your ground active hunters are running along the ground chasing their prey. So they’re probably not going after flying prey as much because they want something that they can chase down on the.

[00:23:30] Michael Hawk: That makes sense. And it actually reminds me, almost missed this, but I’m glad that you mentioned the orb weave. I had a question from a listener. So I asked my listeners if they have any questions for future guests, and I give them a topical content and they said, Why are or weavers so prominent and so large in the autumn?

[00:23:50] Can you tell me a little bit about what’s going on there? Is that spider a spider ling that was hatched in the springtime?

[00:23:56] Sarah Rose: right? So some of the orb weavers, not all of them, but some of them actually emerge in the spring as really small spiders. So actually there’s a lot more spiders. Of that particular kind in the spring because when the egg sacs emerge, there’s gonna be hundreds of baby spiders coming out of that egg sac.

[00:24:14] And then they’re spending the spring and the summer building different size webs at different locations, catching all of those flying insects and growing bigger and bigger. And by the time we get to late summer and fall, that’s when they’re mature adults and that’s when we’re seeing these big webs with the quite large spider sitting in the middle because they’re at their adult stage.

[00:24:34] They then will mate produce an egg sac and then the adults will die for the winter and the young will over winter and the egg sac and emerge in the spring and the cycle starts again. Now I say that for some of them. With spiders, there’s over 50,000 known species of spiders in the world. So there’s not gonna be one life history.

[00:24:54] You can’t just say this is what a spider does and this is its life history because there it’s just so diverse. And even with in the OR weavers, there are some or weavers that over winter as subadult mature in the spring mate and then it’s a completely different timeline or phenology for them.

[00:25:13] So it’s difficult to put things all together in one. But for orb weavers, there does seem to be a good number of them that have that emerge in the spring, grow through the spring and the summer, mature in the late summer fall, may produce your egg sack and then die. And that actually makes sense when we think about the fact that during the winter there’s not usually a whole lot of flying insect prey around for them to be catching.

[00:25:39] Michael Hawk: Yeah, and then that, that could lead to a hypothesis that in areas that do have mild winters, that maybe you find more of those multi-year life cycles or something. I don’t know.

[00:25:50] Sarah Rose: There are some here in like Ohio where we do get really cold winters that the orb weavers that over winter as adults or sub-adult stages. And what they do is they just go into a torper for the winter. So when they get cold enough, they’re basically, their metabolism slows down to the point that they’re basically in a coma like hibernating for the winter.

[00:26:07] So even with the cold winters, there are cases, but yeah, there are, like if you were in Florida, there’s probably more orb weavers that are gonna be active during the winter because there’s more.

[00:26:18] Michael Hawk: That’s really cool. And I, want to ask about those ones that you have in Ohio that go into Toper. Are they finding a place where they stay above freezing or can they actually freeze?

[00:26:27] Sarah Rose: Spiders actually contain an antifreeze substance within their bodies. So you can. You could, if you got them really cold, you could freeze ’em. But at normal temperatures you can’t freeze them. So the funny thing is, when I took an entomology class and we went out and we did a whole bunch of sweep netting in a meadow and the answer was to just take the tie off the sweep net and put it in their freezer overnight.

[00:26:49] Cuz the entomologist thing was you come back the next day, you dump it out on the table and you can collect all the insects that you want from it, because having been put in the freezer of, they’re dead. The catch is the spiders will wake up when they get warm again and start crawling around on the table, which even a lot of entomologists are aach phobic.

[00:27:06] So that was a lot of fun in the classroom to suddenly have all these spiders bringing back to life after being in the freezer overnight and crawling around on the table.

[00:27:15] Michael Hawk: That’s interesting. And I, the other thought that came to mind is if some of those spiders were maybe predatory on the other insects that were in there, those those insects that you just caught maybe become a meal for the spider.

[00:27:25] Sarah Rose: Yeah,

[00:27:26] Michael Hawk: Let me get back on track to what I had asked about before taking you on this tangent. And you were talking about the guild structures which was new to me, by the way.

[00:27:36] I hadn’t seen that until I purchased your book, so I totally missed this. And it makes a lot of sense. So maybe from there you talked about some guilds use web, some guilds don’t use webs. Maybe we can look at some of the the web building spiders and the diversity that exists in those sets.

[00:27:53] Sarah Rose: Yeah, there’s four of the guilds that use webs for prey capture. We have our sensing web guild, and although their webs don’t actually catch the prey I think of it more of a prey detection system. Those are things like our trap door spiders that would haves. Silk lines that radiate out from their borough.

[00:28:11] They’ll sit at the entrance of the borough and they can sense the movement of insects when they walk across their trip lines. So they detect the prey with their web. Instead of the web actually being used for prey capture, there are sheet web weavers whose web is basically a two-dimensional sheet.

[00:28:28] Sometimes it could be pulled into a bowl shaped or curved into a dome shape. But there it’s basically a sheet. Some of them also would have a funnel retreat at one end of it. That’s non sticky silk. So pray that gets caught in that web is just basically getting snagged. If you look at detailed photos of a lot of insects, they have lots of little spines and claws and hairs and things on their legs.

[00:28:52] So when they land on a web, it doesn’t take much for those things to get tangled in there and they have to try and pull free. So for example, grass fighters in the genus, a synopsis are a great example of this. They’re lightning fast. When something hits their web, they run out of their little funnel retreat to grab the prey item because the prey item could potentially break free cuz it’s not stuck to the web. We have our orb weavers which is what most people think of as a spider web. The round with a sticky spiral. Although sometimes it can be modified. There’s some that make just like one pie segment. Out of the orb web. And that oftentimes is using sticky silk. Not always, but there’s some sort of glue on the silk.

[00:29:35] So when the insect hits the web, they’re stuck to the web. So then for the last of the web building, we have the space web, we weavers they build a web that oftentimes looks like chaos. There doesn’t seem to be any set structure. It just fills a three dimensional space and it goes all over the place.

[00:29:53] Some people call them tangle webs or cobwebs. The things that you get in your corner of your house where there’s just this massive silk going in all different directions. And they have some great hunting techniques that are very specific to, to that group. And then we have our four guilds that don’t.

[00:30:10] A web for prey capture, and that was just basically splitting them by where they hunt. So the ground active hunters, the other active hunters, the ambush hunters. And then the last one is our spider hunters, which are specifically targeting other spiders. So our ground active are gonna be mainly on the ground, other active maybe up on buildings or on plants.

[00:30:31] Our ambush hunters are really the sit and wait. I love the crab spiders that, that they sit there with those front two pair of legs just extended waiting to give free hugs to any insect that happens to come close

[00:30:43] Michael Hawk: free Hugs,

[00:30:44] Sarah Rose: So it just really does come down to where they’re hunting and how they’re hunting.

[00:30:48] So if you think about, you look at different habitats there, there’s different options available. So you, in order to put a big orb web up, you need structure to attach the web two. So if you have a mode front lawn with two inches of grass and that’s all you have, you’re not gonna have any of the orb weavers, cuz there’s nothing for them to attach their web to until they get to your house.

[00:31:12] And then your front porch is gonna be a perfect location because there’s actually something to attach to. But with that, you have a lot of ground surface. So you can have your ground active hunters that are gonna be out there running around on the ground, chasing down all of your ground dwelling.

[00:31:26] Michael Hawk: Right. And that reminds me of a couple of questions that I personally have. So the orb weaver, spiders, so many of them seem to rebuild their webs almost every day. Maybe it is every day. And since that’s a sticky web, is that, is it just to make sure it’s fresh and optimal stickiness or is there any other theories behind that?

[00:31:45] Sarah Rose: I think that, there’s quite a few different things that play into that. So there are some species that literally will take down the web every morning. They consume the silk when they take down the web so that they’re getting that protein back to be able to produce new silk in the evening. And then at night they put another web up.

[00:32:01] And one of the big things I’ve heard is especially for those spiders that are only active at night, so they only want the web out during the night, is it means they’re less obvious to predators where they are because there’s no web indicating spider lives here. And also, Oftentimes during the day, the web would get damaged by other things.

[00:32:21] So if you’ve gone ahead and taken it down, recycled those proteins so that you haven’t lost anything, you can then rebuild fresh when the next night rolls around.

[00:32:30] Michael Hawk: Oh yeah, that makes a lot of sense.

[00:32:31] Sarah Rose: There are also some or weavers that will keep a web up until it’s reached that point of disrepair where you can’t just patch it, that the best option is to take it completely down and rebuild.

[00:32:42] So it, it does vary, but the ones that do it every day I’ve heard a couple of different hypotheses and unfortunately we haven’t figured out a way to ask the spider why it does that yet.

[00:32:51] Michael Hawk: Well, let me know when you do figure that out in the future. I think that would make a good episode. And it reminded me of this, unfortunately I haven’t seen one now probably in over a year, but I, for a couple of years I had these tiny little, I think they’re orb weavers that the trash line orb weaver in my backyard.

[00:33:07] And I think that they would leave their webs up for extended periods of time. Can you tell the audience a little bit about the trash line or Weaver and , what they do with their webs?

[00:33:15] Sarah Rose: Yeah, so they’re really cool little spiders. In the middle, usually a vertical line down the middle of the web, they will put the remains of their prey and they’ll ball it up and it’ll make this line the trash line down the middle of the web, which acts as great camouflage for the spider.

[00:33:31] So oftentimes you’ll see the trash line in the middle of the web, and you’ll be looking at it, and you won’t see the spider unless you actually poke the spider and get it to move. So it’s great camouflage for the spider. Some of the species actually also hide their egg sacs within those . The line of debris.

[00:33:48] And when they rebuild the web, they leave the trash line intact, so they’ll take down the rest of the web and spin the rest of the web new, leaving the trash line. So it’ll start as a really thin line, a little bit of debris in the spring. And then as the year goes on and they’ve accumulated more and more prey items, you’ll get a really bigger, longer, thicker trash line

[00:34:10] Michael Hawk: Yeah, it’s pretty cool in the adult spider, in the middle of the web. As you pointed out, I didn’t even recognize it was there. I just was taking pictures and when I was looking at my photos, I was like, Oh, wait a minute. That is the spider right there. And it had its legs all tucked in.

[00:34:22] It made it really hard to identify. And then, sorry, I’m making this about my yard we have a lot of I think it’s the Western Black Widow it’s one of the black widows. Anyway, they make one of those really three dimensional tangly webs, like you were talking about. And they often get really full of debris as well, like leaf litter and random things.

[00:34:43] And it seems like they don’t care. They just let that stuff sit in the web. Does that relate to their hunting style or any other aspect of their life?

[00:34:52] Sarah Rose: So the, I love the black widows. I think they’re beautiful spiders. And one thing I would point out to your listeners is black widow silk is really strong silk equivalent to almost feeling like you’re trying to snap fishing line. I know someone that had a black widow that put its web behind their sofa and when they pulled the sofa out from the wall, they said it sounded like they were popping bubble wrap because it was snapping the lines that it’s so strong.

[00:35:17] So if you think you’re looking at a black widow web, one of the ways to tell is if it’s really strong silk. And yeah, they built this big, messy tangle. It’s just, and I almost do think it’s just random that they just put all these different silk lines, cuz I actually have had captive black widows and watched them have to cut their silk lines to get to the prey.

[00:35:34] So I think they just put up random silk lines and because of that, that it does catch a lot of debris. I’ve seen them sometimes go in and start taking some of the debris out, cutting it out and dropping it out of the web. But I don’t think it really impacts their ability to capture prey seen as most of the time they do leave it.

[00:35:53] And a lot of times what they’re going for is they. A lot of the cobweb weavers, so the family, the day, which black widows belong to create what are called gum foot lines. So they’ll have this big tangle web, and then from the bottom of the web to the ground, they’ll have these straight lines that are stretched down and glued to the ground.

[00:36:13] They’re sticky at the bottom, and the glue that’s holding it to the ground isn’t particularly strong. So anything that walks into those at the bottom, The silk will stick to what’s walked through it and then break from the ground and it’ll actually like hoist the prey item up into the web. And so one of the things that a lot of the, of the, the DIDs do is they let that prey of sit there and struggle and struggle and struggle and get tired out before they go in for the bite.

[00:36:37] So I’ve heard people comment that they think a black widow bite can happen is if you stick your finger in the web accidentally and it thinks your prey’s gonna run over and bite you. If you ever watch one taking down its prey, the bite doesn’t happen until they’re pretty sure that that prey item is secure and it’s no longer a threat to them.

[00:36:55] So biting is not the first thing they do, but yeah, that just tangle and just things getting caught in there. And I wonder sometimes if having the debris there makes things think that’s no longer a threat.

[00:37:07] Michael Hawk: It’s like a camouflage.

[00:37:09] Sarah Rose: Yeah.

[00:37:10] Michael Hawk: Interesting. So I like my black widows. We have a lot of them around the house. And not inside. I don’t, I try not to have them inside, but but outside. And my observation is, as you described, they’re generally very reclusive and, they’re out at night, not during the day. They’re usually hiding.

[00:37:27] But if someone were to encounter one, do they ever bite in defense or is it strictly to subdue a prey item?

[00:37:35] Sarah Rose: So the only time they’ll bite a human is in defense. And there’s actually a great paper. David Nelson and his group did a study where they took black widows into captivity and they made fake fingers and manipulated the spiders using these fake fingers to see what does it take for a black widow to bite somebody.

[00:37:53] And like a lot of snakes, they can also dry bite. So if you’re just manipulating them and they’re really not happy