 We have a presentation on vernal pools with Steve Tacho from the Vermont Center for Eco Studies. I met Steve about 25 years ago when he was working for VINs. And I had just taken a teaching position at Brain Free, which was half time at that point. I was looking for something else to do and we got an indoor job at VINs. Which was perfect for me. I could work through a lot of the work at home, come in three mornings a week. And the best thing about that job is that I could come in very early in the morning and work with Steve and Chris Rimmer and Kent McFarland, conservation biologist there, taking birds out of the nets and banning them. And Steve and his friends were very kind to let a newbie like me help out in that position. But Steve and Chris and Kent left in the late 90s? No, I think it was eleven years ago, yeah. To found the Vermont Center for Eco Studies. Steve is still very interested in birds, as they all are there. But he is the lead person for vernal pools. And he's going to talk with us tonight, share some of his expertise. Thank you Steve. Sure, thanks Tom. Happy to be here tonight. After three beautiful days, we're kind of back to the reality of April. A little cooler weather, but still isn't too bad out there. Maybe some of you have seen some amphibian migration last weekend. There's a lot happening last weekend, a lot of movement going on. So we'll talk a little bit about some of that stuff tonight. Before I start, I just want to mention I have some handouts up here. You're welcome to help yourself too. There's three related to vernal pools. It's kind of an overview of what vernal pools are. There's one about some research I did a while back doing some radio telemetry with salamanders. To see how far salamanders move away from vernal pools in the summer. So we know how much habitat they need around these vernal pools. So that summarizes that research. And then there's another one talking about force management guidelines around vernal pools. We're kind of related a follow up to that research. Kind of the reason why we did that research was to find out how much habitat they need. And then talk about how we can better manage the forest in those areas. And suggest the guidelines for that. This is our Vermont Center for Eco Studies. This is our current newsletter, which was last fall's newsletter. Our spring newsletter isn't out yet. We do a newsletter twice a year. And then this report is something that I published a couple of years ago. The status of vermal forest birds. This is a summary of 25 years of bird monitoring in Vermont in forest habitats. So if you're interested in any of that, feel free to make one of those up. All right. I would encourage you to ask questions as we go along. Try to keep it informal as we go. I have some videos to show as we go. I don't know if we can turn out the lights. Maybe it might be a little bit better. Keep trying. One of those will work. There we go. There we go. Usually I bring a couple of books with me that I'd like to show to the group as additional reference materials. But my intern has absconded with my vernal pool books. And I can't seem to get them back. So a couple of slides of my two favorite vernal pool books. The one on the left, vernal pools, natural history and conservation by Elizabeth Colburn is a great sort of armchair naturalist kind of natural history and look at vernal pools really in depth about what they are, their values, and a lot about the animals that utilize them. She's particularly strong with invertebrates. So the chapter on invertebrates is really good. The book on the right, Science and Conservation of Vernal Pools by the editors are Aram Calhoun and Philip de Menardier both from Maine. This is a little bit more of a scientific approach to the natural history and science of vernal pools. A very good book. It's pretty expensive. Like, you know, we're talking like $120. It's kind of a textbook. Elizabeth Colburn's book is more like $30 or $40. Both really good references. And then finally, my favorite field guide is this little field guide to the animals of vernal pools. Really great resorts, colored photographs and illustrations throughout. It's waterproof so you can take it out in the field on rainy days. And it's only $12 from the Massachusetts Fish and Wildlife Department. Don't buy it on Amazon because it's like 40 bucks on Amazon. But $12 from Massachusetts Fish and Wildlife. So great, that's a great little resource. All right, so as we gaze into the reflection of a vernal pool, I'd like to start off, if I can find my, here it is over here. I'll start off with a poem by Robert Frost. Some of you may know it's called Spring Pools. I might, well, we'll see if I can get through. I might need a light, yeah. Thanks. These pools that, though in forests, still reflect the sky almost without defect. And like the flowers beside them, chill and shiver. Will, like the flowers beside them, soon be gone. And yet, not out by any brook or river, but up by roots to bring dark foliage on. The trees that have it in their pent up buds to darken nature and become summer woods, let them think twice before they use their powers to blot out and drink up and sweep away these flowery waters and these watery flowers from snow that melted only yesterday. All right, we can hit the lights back and sorry to spoil the mood with turning the lights back on. All right, just a brief outline. I'm going to talk about what vernal pools are, kind of their values and their functions in the ecosystem. Focus a lot on the natural history and ecology of some of the animals that utilize vernal pools, mostly the amphibians, but we'll also touch on some of the invertebrates. And then I'll finish up with just touching on a couple of the projects that I'm working on that also involve volunteers in case you're interested in getting involved. So what are our vernal pools? Well, they're these small, temporary wetlands that usually occur in forested situations. They're shallow, usually only a foot or two, maybe occasionally deeper than that, isolated from other types of wetlands, other permanent wetlands. They usually have these fairly well defined boundaries. They're not sort of like big swamps that can sort of go on forever or be hard to define. They're usually fairly easily defined and they're small. Most vernal pools in Vermont are less than a tenth of an acre in size. Of about almost a thousand pools that we visited in Vermont, about 70% are less than a tenth of an acre. And then about another 20% are less than a quarter of an acre. So they can be larger. There are some that are an acre in size, but most of them are quite small, shallow, isolated from permanent wetlands. They're fed primarily by surface water. So runoff, spring rains, snow melt, and they usually is not a connection to the ground water supply. You'll notice I'm saying a lot of usualties. There's very often in nature there aren't these hard and fast rules. There's a lot of gray areas where sometimes we can't really say, is that a vernal pool? It's more of a seep, but it's functioning like a vernal pool because it's deep enough and it holds water long enough. So there's some gray areas. They have this distinct seasonal hydrology. That's one of the important things about them is that they dry out, if not every year, then in most years, or maybe only in drought years. That helps to prohibit fish populations from becoming established. And that's really key for the animals that use vernal pools because these are animals that haven't evolved with fish predators. So the amphibians that use vernal pools don't have any defenses against fish unlike amphibians that live in ponds like green frogs and bullfrogs and newts. Their eggs, their tadpoles are all toxic. Fish learn very quickly not to eat them, but the amphibians that use vernal pools don't have those defenses. So they would be quickly consumed by predatory fish if they were to be established in a vernal pool. So seasonal hydrology, they're usually filled full to the brim this time of year and then as the season progresses, that water level declines due to, you know, as the spring rains sort of diminish, temperatures increase over the summer. There's more evapotranspiration through the trees and just evaporation and the vernal pools slowly will dry. Usually by August, most vernal pools are dry, August or September. Unless it's a really wet year, they may retain some water or they may retain water. There are some semi-permanent pools that function as vernal pools, they only dry out in drought years but remains moist or wet many other years. In order for there to be successful breeding with amphibians, they really need to hold water for at least three months. And the longer of the hydro period of a vernal pool, the longer the period that it holds water, usually leads to a greater increase in the species diversity. So you can have these short hydro period pools, they might be pools that only hold water for a month or two. They're probably not going to support successful breeding for amphibians, but there might be a few dozen species of invertebrates that can live there. But then you get vernal pools that last three months or four months and you're going to have a lot more invertebrate community, a lot higher diversity, and you're also going to have a lot higher diversity of amphibians that use those pools. What we don't know is how climate change is going to affect vernal pools. We know that the predictions for climate change are for more greater intensity of storms. That could be a good thing. It could mean that vernal pools will, the hydro periods of vernal pools won't change too much because those intense storms will tend to reflood them, keep them flooded. But if we do have warmer summers, that could mean that we could shorten the hydro period and that could have a big effect on the success of vernal pools. And the last characteristic is that they provide critical habitat for a variety of invertebrates and amphibians. For the amphibians, it's just breeding habitat. These amphibians don't need these vernal pools as adults. They only migrate there to lay their eggs and then they return to the forest. The eggs and the tadpoles need the vernal pools to develop, but the adults are just using them as a nursery, just as a place for those eggs and tadpoles to develop. The invertebrates are a mixed bag. Some of them spend their entire lives in vernal pools. Others just go through a developmental phase and as adults they can leave. And others like the predacious diving beetle on the left, they have the capability of flying as an adult. So they might land in a vernal pool and spend a few weeks or months there, and then they can fly to another water body as the pool shrinks up. So there are literally dozens, if not hundreds, of species of invertebrates that you can find in vernal pools. That's where the real diversity is. A fewer number of amphibians that you'll find. And it's one of the only ecosystems, it's the only one I can think of that's defined by its animal community rather than its plant community. So usually you think of a natural community like a red maple swamp or a beech maple forest or a spruce fir forest or a sedge meadow, something like that. It's always defined by the plants that are found there. Vernal pools don't have any characteristic plants. In fact, they're pretty devoid of plants for the most part. So they're really defined more by their animal communities. Pretty unique in that way. If I'd say in the last probably 10 years, ecologists have really come to the realization that vernal pools are a keystone ecosystem. And by that, I mean they have a very big influence on the surrounding forest community than you would expect based on the size. I mean you might have a vernal pool the size of this room. It's not a very big water body, but it can have a big influence on the surrounding community. So we call that a keystone ecosystem. They're also keystone species that have a big influence on the surrounding community. Probably the most common or the most talked about is the beaver. Beavers have a huge influence on the surrounding ecosystems because of their ability to build dams, create wetlands, and then move on. And while there's not a lot of data on what that influence is, how that's hard, kind of fast information about what that influence is, it's primarily in the impact it has in the food chain or the food web of the surrounding forest. So this guy, probably the best hit is from Brian Windmiller, who is a PhD student at Tufts University back in the 90s. And as part of his PhD, he estimated the biomass, the weight of all the breeding birds, all the small mammals and all the amphibians in a 50-acre forest surrounding a single vernal pool in suburban, just outside of Austin, in suburban Concord, Massachusetts. And so his estimates, here's what he came up with. He came up with 13 pounds of breeding birds in this 50-acre forest, 108 pounds of small mammals, which, if I recall correctly, were squirrel size and smaller. And of the seven species of amphibians that bred in this vernal pool, he came up with 271 pounds of amphibians. So that's a pretty big influence on the surrounding forest. More biomass than mammals and birds put together, at least small mammals. And I kind of think of vernal pools as like fast food joints in the forest. A lot of animals take advantage of them either during the breeding season when the adults are there. There are a number of species that really key in on that activity to get their food. And then later in the summer, after the breeding's over, and all those little metamorphs, all those little amphibians, frogs and salamanders are leaving the pool, and they're just little protein snacks hopping out of the water that are available for a lot of other animals to take advantage of. So a huge amount of energy being transferred from an aquatic system to the terrestrial forest. So here's a good example. Garter snakes are one of the bigger predators of amphibians. They really key in on them. And as well as a lot of mammals, raccoons, often will take advantage of vernal pools. This is a game camera from Waybridge, Vermont, set up on a vernal pool that these volunteers are monitoring. That pole in the middle is a PVC pipe that we give them to put in the vernal pool to measure the water height and then attach to the bottom of that PVC pipe is a little temperature logger. So it measures the water temperature every hour throughout the whole summer. And the main reason for that is so that when the pool dries, we'll know exactly when that happens because the temperatures will start changing dramatically. Instead of being consistent with the water temperature, it'll start reading the air temperature. So we'll have an exact record of when that pool dried. So we're doing this with pools all over the state. But anyway, he's got a game camera set up and here he's got a whole group of raccoons feeding on the edge of the pool. That was on April 9th, just a couple weeks ago. And then the next night, he's got a couple of bar dals, one bar dals sitting on the pole, the other bar dals up in the upper left in flight. So it's kind of blurry. April 10th, and then here's April 14th. Same two bar dals. Bar dals are probably the most common predator I see at vernal pools. I don't think it's any coincidence that bar dals chicks hatch this time of year. They take full advantage of the bounty that they can get at vernal pools, especially when the wood frogs are coursing and breeding. But we have a little video here we're going to go to. This is a game camera set up elsewhere. I'm just going to pause it for a moment. This is a game camera set up in Keen, New Hampshire. And I'm not going to watch the whole video, but we're going to scroll through it a little bit. We have a bar dail coming to a vernal pool night after night. This is May 2nd. I'm going to scroll ahead to another night here. Day and night, actually. This bar dail is hunting. Here it is waiting around in the leaf litter, picking up things. And there's one point in here where he picks up a salamander. He flew away with something there. I think it's right about here. Yes, he's going to pick up a salamander in his beak. Right. He's coming up. He's got it in his foot there. There it is. He's got it in his beak right there. So waiting around, actually finding spotted salamanders with its feet. Pretty remarkable stuff. So yeah, if I go to a vernal pool at night, you're guaranteed to see bar dail there, because it's really common. So a lot of the wildlife that vernal pools support are really dependent on forested habitat. And so vernal pools are really, really important in these forested systems. Of course, you can find vernal pools in fields. What's a field? Around here, but a cleared forest. And if you let it go long enough, it'll grow back to forest. But they're really dependent on forested habitat for a number of reasons. One of them is that the base of the food chain in the vernal pool is the leaf litter that falls into the pool. It's a detritus-based food web. So that leaf litter, in this case, primarily from beach leaves that have fallen into the forest, into the pool, is the base of the food chain. And species like catasfly larvae and isopods up in the upper right, two very abundant invertebrates in vernal pools, they're shredders. They shred leaf litter up into smaller pieces to eat it. And as they're doing that, it speeds up the decomposition of the leaf litter in the vernal pools as well as speeds up the growth of what's called paraffitin, which is sort of a fuzz that grows on leaf litter and on sticks in vernal pools. It looks like a fuzz. It's a complex, nutrient-rich fuzz. That's a technical term. That's made up of fungi and bacteria and algae and something else I'm forgetting is in there too. And it's really important for the wood frog tadpoles. That's primarily what they feed on, especially when they're fairly young. They feed on that paraffitin. They'll also feed on some algae. And as they get older, they'll also feed on some animal matter as well. So the forest, the connection to the forest is important for vernal pools. Some of the other invertebrates include this really unique species, the fairy shrimp. We don't know. This is the knob-lipped fairy shrimp, which is the one I see. It's the only one I've seen in Vermont. Some people have said they've seen this on other species in more in southern Vermont. A really unique organism. They're found all over the globe. They are a shrimp. They're a crustacean. They're about an inch long, maybe three quarters when they're full grown, three quarters of an inch or so. They're probably hatching about this time of year, maybe a little bit later. And they're very small when they hatch. They go through a number of instars, a number of growth spurts, growth phases before they reach the adult size, probably by mid-May or early May, when they'll mate. They'll lay eggs and then the adults will die. The eggs sink to the bottom of the pool and wait for that to happen again. There's not a whole lot we know other than that kind of those basics. There have been some research to suggest that their eggs have to go through a period of drying and freezing before they become viable. We don't know if that's true for all species or just some. But what I do know is that some years you go to a vernal pool and there'll be millions of fairy shrimp. I can't miss them. They're everywhere. Other years, you can go to the same vernal pool at the same time of year and there's no fairy shrimp. So they're very enigmatic, really beautiful to watch when they swim, very graceful. And this knob-lipped species is always this orange kind of color, salmon kind of color. As I said, they can be really dense at times, really abundant. And we're going to go to another video just so you can see them, watch how they swim because they can be easy to mistake for other species of invertebrates. It's good to have a search image to know what you're looking for with your fairy shrimp. They look like they're swimming upside down, very graceful with those eight rows of feathery legs. Really beautiful to watch. Very smooth, swimmers. That's a female with the egg sac at the base of the tail. All right, that's that. All right, let's talk a little about the amphibians, which is kind of my, more of my area of expertise in the invertebrates, although I am very interested in fairy shrimp and learning more about their ecology. So these are the four species that are really vernal pool dependent. So starting on the left, the spotted salamander, which is kind of the poster child of the vernal pool movement. In the middle is the blue-spotted salamander, a little bit more rare and less widely distributed. On the far right is the Jefferson salamander, and on the bottom the wood frog. These are the four that are really dependent. There are other species that will use vernal pools, spring peepers will, great tree frogs will, but they're not really dependent on them so much. They're actually, I would say they're more common in other types of wetlands, those two. And all of these can also use other types of wetlands. They're not limited to just vernal pools, but they're, without vernal pools, these guys are going to be much less common because they can't breed in all kinds of wetlands. For that reason we talked about earlier, they don't have defenses against predators or against fish really. But they can breed in shallow edges of marshes where there's a lot of cover, a lot of vegetation and cover and fish really can't get into those shallower margins. They can breed in some beaver ponds that don't have predatory fish populations and other types of wetlands. But these guys are really the key vernal pool indicators. So let's talk a little bit about these two salamanders, the Jefferson and the Spotted, which tend to share habitats pretty closely. Oh, we got another video. So in the early spring, this time of year, salamanders are migrating to the breeding pools. And when they arrive, usually they're migrating on rainy nights, only on rainy nights, because amphibians are sensitive to dehydration. So they avoid moving in the daytime mostly. Wood frogs will, but salamanders rarely will. When they arrive, the males gather up in these congresses, these groups of males, and they're called congresses. And they're basically just hanging out, it's like a middle school dance with the boys hanging out together hoping that the girls come over and ask them to dance. And that is literally what happens. Okay, when a female approaches the group, she will basically select her partner and they move away from the group. This is just one, getting some air. The two will move away from the group and go through a courtship ritual, which we're not going to see in this video, but it is a great video of a congress. So the courtship ritual is the male and the female sort of dancing on this underwater dance. And then what you might notice, scattered around on the bottom are these little white spots. Those are spermatophores, little sperm packets that the males deposit. So as the male and the female move away from the group, the male will deposit his spermatophores and the female will pick those up. And these are spermatophores. So it's a little jelly capsule that's sort of capped off with a little packet of sperm on the top. And he might drop four or five of these. The female will pick some of them up. I don't know how many she picks up if she picks up just one or two, but she picks them up with her cloaca, which is her vent, where waste is excreted. She picks up those sperm packets and her eggs are fertilized internally. And then a few hours later, she'll deposit eggs. So Steve, I have a question. So if she was a congress with just all the males and the spermatophores there, if the female comes and picks a male, what would she know which spermatophore goes for a male? Well, when she moves away, the male and the female move away from the congress and they go through their dance, he'll actually drop his spermatophores during the dance and she'll pick them up. So that's just a waste that the guys don't hang it out? Exactly, you're correct. What we believe it is, is the young males who know they don't have a chance won't have a dance. Just hoping. So these are what the spermatophores might look like if you arrive the day after the dance. So it's evidence, because chances are very slim, if you go to Overnal Pool during the day, you're going to see salamanders. They're probably there. They're under the leaf litter, but they stay very well hidden. It's really rare to see them during the day, but you can see the evidence that they were there. So at least you know. How long do they usually stay in the Overnal Pool after they fly in there? For the salamanders, it varies by sex. So the males will stay a week or two weeks perhaps. The females will leave shortly after they lay their eggs. They ideally will wait for a rainy night, but they will move just out of the pool and stay right near the edge of the pool underground and wait for a rainy night to be able to move further away from the pool. So the female might only be there for a day or two, and then she wants to get out of there. She doesn't have any other... She's been spending the winter underground. They immediately migrate to these ice cold waters to breed, and then it's time to get some nutrition. The males will hang out longer. So the female will lay from one to three egg masses, really depending on her, probably her age and her fitness. And each egg mass can contain anywhere from about 30 to about 250 eggs. So one female could have as many as 750 or so eggs, or embryos, in these egg masses. When they're laid, they're about the size of a golf ball and they're a little bit smaller, but they pretty quickly swell up to be about the size of a baseball. And they're not always round. They can be sort of oblong shaped, but they're pretty big and impressive. I'll talk a little bit more about identifying egg masses later on. The Jefferson salamander, however, lays these much smaller egg masses, and she might lay from one to three as well, each female, and the egg mass only contains between five and maybe 30 embryos. So a much smaller, much less conspicuous egg mass, with much lower numbers of embryos. And the Jeffersons go through the same kind of ritual that the Spottas do. They have Congresses and the female picks the partner she's interested in. And then the rest of the year, the adults are spent, all leave the pool after a week or two. The adults disperse out into the surrounding forest. And this was the question that part of my research sort of addressed looking at how far did they move after breeding out into the forest. So I radio tagged Spottas salamanders and Jefferson salamanders down at Marsh Billings, Rockefeller forest in a park down in Woodstock, and tracked them through the summer for six months from May to October. And basically they move about 200 yards, up to 200 yards away from the breeding pools. And other studies have pretty much confirmed this with these species as well in other parts of their range. They don't go real far, but it's further than a lot of people would have thought, 200 yards away from the pool. Females tend to go further than the males. We don't know why. And during the rest of the year, they're primarily living underground in small mammal tunnels. They can't dig their own tunnels. They're just not physically capable, but they share these small mammal tunnels that are dug by things like meadow voles and short-tailed shrews and mice, chipmunks. And this was one of my study animals that we're looking at. And almost every day, I could go in the forest. I had a little flag stuck in the ground, a little ground flag, and I could pick up the leaf litter, and there he'd be at this entrance to this tunnel just waiting for something to walk by that he could eat. So these guys are predators. They're eating all kinds of small insects and other invertebrates, centipedes, millipedes, spiders, beetles, worms. And then on rainy nights, they come above ground and move and forage above ground and move further away. So there's definitely an interesting relationship going on between small mammals and salamanders, because they're using the same tunnels together. I don't know if it's mutually beneficial, or if the salamanders are just taking advantage of this and the mammals don't mind. So while these two species, Jefferson's and spotted salamanders have very similar biologies, their conservation status is a little bit different. So spotted salamanders are relatively secure in their range. They have a fairly large range all the way down to the Gulf States and up to the Mississippi River and all across the Northeast. They use a wide variety of wetlands for breeding from vernal pools and beaver ponds. Species of greatest conservation need which is a designation in the Vermont Wildlife Action Plan and that's largely because of their dependence on vernal pools to maintain their current distribution. While the Jefferson salamander has this much smaller global range, it's really more limited to the Ohio Valley in the Northeastern US and a very large percentage of its range is really focused there in the Northeast. And it's really this is one species that is more limited to vernal pools and its breeding, especially around here we find it really limited to primarily sort of upland rich top kind of vernal pools and we don't find it as commonly down in the valleys. It's considered a high priority species of greatest conservation need in both Vermont and New Hampshire and there's some evidence that there may be some population declines, particularly along the edges of its range and that it may be more sensitive to habitat fragmentation than the spotted salamander is. Alright, so here are their distributions as we know it currently in Vermont based from the Vermont Reptile and Amphibian Atlas project. Jefferson salamander on the left spotted salamander on the right which found everywhere in the state. Jefferson salamander is a little more limited in this area. It is found around Orange County in Northern Windsor County and there are some pockets throughout the Champlain Valley and up into parts of Washington County as well. It looks like no records for Randolph or Braintree but there are records in Brookfield and Roxbury in this area and then there's the blue spotted salamander. It's a little beauty, a little bit smaller than the Jefferson to which it's most closely related and it has that beautiful blue flecking on the sides and its distribution again its stronghold here in Vermont is the Champlain Valley but there are these scattered populations and as you see there is at least a few records from Randolph and then down on the southern Connecticut Valley down on the southwest corner and then these scattered records from the northeast kingdom so it's a fairly secretive species, it's a little harder to detect because its egg masses are very small and hard to see. That makes it harder to find this particular species but it has this kind of interesting global range where it's found in the northeast but then there's this big gap where it kind of wraps around the great lakes and up into Canada. So among these these three salamanders it's the one that ranges the furthest north and then there's this really wild thing that goes on or that happened with Jefferson and blue spotted salamanders thousands of years ago where they hybridized and created these these unique unisexual populations of salamanders that are some of them are more closely related to blue spotted so we call them the blue spotted complex some are more closely related to Jefferson salamanders so we call them the Jefferson complex and I literally I could do an hour long talk just about this alone, it's so fascinating these are unisexual populations of salamanders they're all female they need males because they need sperm to activate their eggs to develop but there's no genetic material incorporated into the egg so they lay eggs that are clones of themselves and they're all females so you get but they need males so they're called I forget the term now but anyway they're basically using the males for sex but they're not using any of their genetic material so where you have these hybrid populations these unisexual populations with the with the pure populations they're skewed to the females so you're going to find a population that's two to one females to males whereas in a typical spotted salamander or pure Jefferson population it's going to be skewed male almost two to one male to female so in the long term it's really a dead end because the males are not sharing their genetic material with these unisexual salamanders only with the pure but they don't know which it is that they're mating with and the really wacky thing is they can have this weird genetic makeup in that they you know typical sexual breeding you have a set of chromosomes from mom and a set of chromosomes from dad diploids well these guys can have multiple sets of chromosomes they can be pentaloids or tetraploids up to five or six sets of chromosomes so on the left the top one is a pure blue spotted the one in the middle has one set of chromosomes from blue spotted and one set of chromosomes from Jefferson one on the bottom has one set of chromosomes from blue spotted and one set of chromosomes from Jefferson it's really wacky it does it makes identifying what you have a little bit more difficult because if they have a lot of Jefferson genes and a little bit of blue spotted they might look a little bit like a blue spotted even though they're more of a Jefferson so it makes mapping their distribution really complicated as well you must go a little bit there though because if they're not if they're clones and they're not incorporating how are they getting these extra chromosomes yeah and that I don't know really well they have the latest research that I read showed that they they can incorporate some genetic material sometimes nobody knows what triggers that at first they thought it was temperature because they were able to do it in the lab so they thought maybe it's warmer water temperatures so in the real world it probably would never happen because these guys are breeding when the water temperature is like 34 degrees but in more recent studies of another species that has the same thing going on in Ohio they found that once in a while they incorporated genetic materials they don't know if it's some thing that's turned on by some environmental event or trigger so yeah yet to be determined it's really a fascinating story that is still unfolding and basically the last thing I'll say about this is the theory about how this all started was that during the last glacial event it was one species of salamander that got isolated in two different refugia and they started to evolve a little bit as the glacier retreated they think these populations perhaps met in a few places they were still closely enough related that they could interbreed but they were on their way to becoming two different species and they created these hybrids because the hybrids are not being created now so you can't take a pure Jefferson and made it with a pure blue spotted that doesn't work they're not creating hybrids these hybrids were created centuries ago as these unisexual populations yes really wild alright back to the real world we'll talk about the wood frog a little bit the one frog that's really infernal pool dependent like the salamanders it spends most of its life in the forests around vernal pools and in the early spring you know it migrates to the pools to breed just like the salamanders distribution is statewide probably our most abundant frog perhaps one of our most abundant frogs it's the frog that ranges the furthest north in North America above the Arctic Circle all the way up to Hudson Bay and up to the Arctic Ocean pretty remarkable distribution for a frog and one of the things that allows it to do that is a unique strategy to survive to over winter and we're going to watch a little video here let me just turn the loud enough this frog does something I didn't know was possible as soon as the frog touches just touches an ice crystal says Professor John Costanzo we're away from the center of its body so the frog's internal organs are now wrapped in a puddle of water that then turns to solid ice as it know our feet run for days perhaps even week this little frog feels like a rock except that as it froze the frog flooded itself with a kind of sugar the frog's blood sugar is distributed through the circulatory system like an antifreeze it's harder for the water to freeze so cells stay just dampen up for the animal to hold itself together until the spring time the animal literally is warming up the outside of this little guy somehow his insides, his heart, his brain they fall first his insides warm up before his outsides but somehow it all happens in perfect synchrony every spring well he said we don't know why they come back to life so to speak I think we do this for sex that's why so after spending the winter frozen just under the leaf litter they make a little like hibernaculum like two inches below the leaf litter they thaw out and they make an immediate migration on a cold rainy night to a vernal pool that's like 34 degrees and the first thing they do is start breeding or at least attempting to breed the males arrive first this is a male most of you have probably heard what a wood frog sounds like a duck so the males have these paired vocal sacks on either side of their head the males float around on the pools calling incessantly they haven't eaten since being frozen solid all winter and they're just waiting for the females to arrive they'll attach themselves to anything that they think might be a female which might be other frogs it might be a spotted salamander it might be a herpetologist boot who knows they're extremely amorous and ready for ready for getting on with it so they probably so they can get out and eat something so let's see there we go so unlike the salamanders who have this internal fertilization frogs have external fertilization so the once the male does grab a female it gets into what's known as amplexus with the male on top of the female the females are typically larger because they're carrying the eggs so they need to be they need to be larger and they're often this reddish color in the spring really beautiful the males tend to be darker brown in the spring during the summer when you see them they're usually very tan so they get into amplexus as the female begins to deposit the eggs she vibrates a little bit and that's a signal to the male to release the sperm into the water and as the eggs are being laid they're fertilized at the moment of being laid so no internal fertilization eggs are usually usually laid in these large communal masses very often so each female only lays one egg mass and it's again about the size of a golf ball when she lays it and it quickly swells up to a baseball size but again you often have these communal masses which probably helps to increase solar absorption big dark mat floating in the water also can reduce predation because there's safety in numbers those at the middle are going to be much more protected and may also protect a lot of the eggs from temperature extremes because again those in the middle are going to be more protected during cold snaps let's just look at the four eggs of these four species that we just talked about the four amphibians starting in the bottom left spotted salamander which is very common as I've contributed all salamander eggs have a jelly around the embryo and then they have a whole the whole mass of embryos is encased in another mass of jelly a matrix of jelly and you can clearly see that outer jelly matrix on the spotted salamander egg mass that's the key to knowing whether it's a salamander or an egg contrast that with the wood frog eggs on the right on the bottom they appear kind of lumpy there's no outer jelly matrix holding it all together so each of those little individual embryos could sort of slough off and become smaller little clumps of eggs and they're fairly fragile in that respect when you pick them up the egg mass can break into several pieces whereas a spotted salamander egg mass is really pretty firm and well protected so then we'll go to the other salamanders the upper left is the Jefferson it does have an outer jelly matrix but again it's hard to see because it's very thin the embryos themselves are smaller there's a fewer number of embryos and they tend to be very cylindrical in shape very often and then the blue spotted are really hard to see just laid on the bottom of the leaf litter a single egg or maybe two or three together like this small little clump so they're very hard to find and then the unisexual egg masses often have a lot of imviable or dead embryos that are just white pure white so they have a high proportion I didn't put in a slide of that but sometimes 60-70% of the embryos are not viable and I'm not sure why that is if that's because they didn't maybe they were they didn't get activated by the sperm they picked up or maybe there's something else going on with the unisexuals that we don't know this is really fascinating though spotted salamanders for more than 100 years we've known that there's this algae that grows in spotted salamander eggs some of the early naturalists noted this and named it oophilia amblystomatis it's a unique algae that only is found in spotted salamander egg masses but more recently they discovered that it's not just in the salamander eggs it's in the salamander embryos it's in and it's actually in some adult salamanders in their cells algae growing in a vertebrate cell it's the only known case of algae growing inside of a vertebrate cell so now they're wondering if to the adults actually pass it on to the to the egg masses at first they thought well the algae finds the egg mass and starts growing in the egg mass but now it's thinking maybe it's the other way around maybe the adults are passing that algae to the egg mass what's the benefit well the photosynthesis of the algae produces more oxygen for the embryos so in these low oxygen breeding sites where they're often breeding where there's very low oxygen shallow water fairly warm at times they're providing more oxygen for the embryos to develop and their byproducts the urine from the embryos is being used by the algae inside the adults yeah we don't know that I don't know if anybody knows that yet so the larva the eggs depending on species spotted salamander eggs might hatch in anywhere from let's see probably I'm just getting three weeks to maybe a month or so the eggs will hatch fairly quickly might be just ten days to two weeks depending on water temperature there because of the big variation the warmer it is the more speedy their development the salamander larvae have these feathery gills on the top there wood frog tadpoles look like tadpoles with a big head internal gills and the big tail salamanders are predators their larvae are predators so as when they first hatch they're feeding on primarily zooplankton and as they grow they'll feed on larger things like copepods or sometimes even small insects or other invertebrates wood frog tadpoles are omnivores they're mostly feeding again on that paraffitin that fuzz high nutrient rich fuzz and both of these have fairly high mortality rates so on average it's 80 to 90 percent that's on average which includes years where the pool dries and there's 100 percent mortality in a good year 30 or 40 percent mortality might be normal in a good year when there's a lot of water but on average high mortality so the adults are taking their chances with a lot of offspring no parental care no time and caring protecting their young just laying the eggs getting out of there and hoping for the best the juvenile stage so late summer 2 to 3 months after the eggs are laid the young are leaving the pools so for wood frogs it might be as early as mid or late July salamanders it's usually in early August but there's some flexibility there so they'll stay in the pool longer because they'll get bigger and their survivorship is better the longer they stay in the pool so once they leave this is their sort of dispersal period the upper left photo is a young spotted salamander about 2 months old so this was in September or October I found this guy on my hand on the far right is probably a 2 year old or so this is the period where they're wandering the forest wandering the landscape they could go for miles before they become an adult salamanders are long lived surprisingly long lived 20, 25 years maybe 30 years wood frogs don't live so long but the salamanders take 4 to 5 years to reach adult breeding age so during that period is when they're dispersing colonizing new areas and sharing genetic material they all don't return to the same pool where they were born that wouldn't be genetically viable for very long some do but they all don't there has to be genetic exchange between pools the salamanders probably only live 2 to 3 years maybe 4 if a female breeds twice in her lifetime that's probably pretty good for a wood frog they're about an inch long when they leave the pools sometimes half an inch long they're usually mature sexually mature in the following spring it might take 2 years to leave the pool early and they were really small frogs are much better dispersers than salamanders because well they can hop they're just better at getting across the ground all right so we mentioned that we know that these animals spend most of their lives in the forests around pools so we know that those habitats are important for their longevity so we know if you're going to think about conserving these species of course we need to conserve their breeding pools the blue dots on this graphic those are the pools then we also need to think about how much habitat around those pools we need to think about if you're doing forestry or trying to develop a conservation strategy or conservation plan for a piece of land so generally as we talked about earlier 175 meters or 200 yards or so is kind of a life zone for these amphibians that's the area that the adults need around the pools to survive but you also need to think about maintaining some sort of connections between those pools depending on how far apart they are and what's between them so in this case this pool that's further to the left you want to try to maintain some forested habitat between the other pools to exchange between those pools we also know that roads are pretty bad for amphibians if they have to cross the roads between their overwintering sites and their breeding sites so there's been a lot of work being done on that as well so let's just finish up by talking a little bit about some of the projects that I've got going on for for vernal pool conservation so the first is mapping vernal pools and I know some towns have been actively mapping vernal pools Tom and Braintree have been doing some mapping of their vernal pools that's a project I started I don't know seven or eight years ago and it's ongoing most recently we just started the vernal pool monitoring project last year this is our first full year of data collection for the monitoring project and then the next thing I'm looking to do is to really start promoting the use of best management practices around vernal pools so I'm just going to talk a little bit about the mapping and the monitoring projects just very briefly the mapping project was started for the simple reason that if you don't know where something is you can't conserve it and we didn't know where the vernal pools were because vernal pools typically don't appear on the national wetland inventory maps the NWI maps or on the Vermont state wetland inventory map so these are all the inventory wetlands in Woodstock then we did a project just in Woodstock and mapped the vernal pools and almost no overlap between them so we know that they don't appear on the wetland map so we wanted to know where they are in the state and maybe we had where they were so we did some color aerial photo interpretation to locate vernal pools and the other thing we knew through this process is that we were losing vernal pools so right in the middle of this color infrared aerial photograph right there is a classic vernal pool in these color infrared photos anything red is actively photosynthesizing these photos are taken typically in early May before the leaf out occurs so you can see water water shows up as a really clean black and that's a very classic vernal pool there's no streams going in and out of it like a permanent pond would have it's a vernal pool this was a 1991 photo 10 years later there's a house and a barn built right where that vernal pool was so we knew that we were and so the wetland office also made a change to the regulations about how vernal pools are protected now vernal pools are considered class 2 wetlands if they have evidence of amphibians using them for breeding so they're regulated on a state level that was that occurred about the same time 7 or 8 years ago with the new wetland rules so here's the map that we came up with mapping all these potential pools across Vermont almost 5,000 potential pools using just these aerial photo interpretation then for a couple years we did a big effort to go out and field verify as many of those as we could mostly on public lands where we didn't have to get landowner permission although we did get some sites where we had landowner permission so to date we've field verified almost a thousand vernal pools in the state but we have a long way to go to verify all of them and of course our mapping didn't pick up all of them and our mapping also picked up a lot of false positives so what we thought were pools sometimes turned out to be seeps instead of vernal pools or sometimes turned out to be something else like one was a big water dump it's just a big pile of tires in the woods or sometimes it's just a shadow from a big conifer in the woods that look like water on the aerial photo so what we're still hoping people will do will get out and help us to field verify vernal pools you can either do it on your own property or on you know neighbor's property you do need landowner permission because these data if you submit it to the vernal pool or to the atlas it's eventually goes to the state as a wetland layer so they do need landowner permission for that if you're collecting the data on the ground alright where are we okay and so we'll just finish up with the monitoring project this is an effort to really collect long term data on a suite of vernal pools all over the state I think we're up to almost 50 vernal pools in the state that we're monitoring this is a citizen science project so it's teams of two volunteers sort of adopt the vernal pool you go out to that vernal pool four times during the year the first time is just to set out the equipment there's that water temperature logger that automatically logs the water temperature to tell us how long the pool holds water there's a little digital recorder that we set out that's programmed to record for about records for about a half hour during the night during the evenings from the time you set it out till the batteries run out and that's mostly just to pick up the wood frog the onset of the wood frog calling so we know exactly the one wood frog start breeding that's a good indicator of when the salamanders start breeding as well and it's mostly to look at the phenology the timing of that breeding is it does it stay the same going 10-20 years down the road or is it getting earlier with climate change then we also do egg mass counts we do another visit about this time of year where you walk the perimeter of the pool and you count wood frog and salamander egg masses give us an idea of the size of those populations and the breeding effort and then you do another egg mass count a few weeks later and you're also we're also inventorying or counting doing some quick counts of two invertebrates cattus fly larva which are really common very abundant easy to see and you basically just do a quick count in a meter square plot at four points in the pool and then if they're a fairy shrimp you do the same thing for fairy shrimp fairy shrimp they're not but we're just counting to make it something that everyone can do because vernal pools are different sizes and different shapes different depths to try to standardize it for everyone we're just counting within a meter of the shore so you walk around and count any eggs within a meter and if you can see eggs deeper you can do an estimated count further out deeper water but sometimes you know some pools are very ten and the water is very ten stained and you can't see very far into the pools some pools are big and three feet deep and you can't count the egg masses and we also really didn't want people waiting into the water to try to count every single egg mass first of all it can be dangerous the water is cold it's in the 30's some of these pools are deep but also there are some diseases that can be spread from pool to pool that you can get on your boots and transfer from pool to pool so we just felt easier not to have people actually going into the water to count eggs so those are the reasons we've just doing a sample of the egg masses and I think those are the basic the basic things we're monitoring other than sort of standardized things like depth, how the water level changes weather size things like that so that's it be happy to try to entertain any questions I'm going to turn it to a good point thanks we spotted so many navigators across the stream they can yeah one of my radio tagged salamanders went across a pretty good stream that surprised me but yeah they wouldn't cross the first branch of the white river probably but a stream I've only seen one in a few years they can get large they grow throughout their life they never stop growing and because they're long lived I've seen them 10 inches long more typical is 6 6 inches females are bigger than the males they have to carry the eggs so they're bigger and so there are owls that are preying on some mammals so minks, mink will prey on them raccoons and hawks probably hawks and red-shouldered hawks in particular again I don't think it's a coincidence and broadwing hawks are arriving like right now I'm certain that they're following the migrating wood frogs from Connecticut up through New England because they arrived first broadwing I saw was last Friday they might choose one pool over another in one year just because they tended over winter nearby probably but the one thing that complicates all this information about these species these amphibians are really hard to study long term because our typical ways of marking animals doesn't work with amphibians so it's really hard to track them over many years with birds we can put a band on their leg and they carry that band for their life with salamanders we can't do that because they shed their skin and the same with frogs they shed their skin multiple times during the summer and having something attached to them gets in the way so you can't attach things to them they breathe through their skin so there have been some more high tech ways where you can insert almost like a grocery scanner tax pit tags they basically have a code and you catch an animal and you rub your wand over it or swipe your wand and see if it's one of your animals but it's fairly expensive it's not as inexpensive as bird banging so again it's hard to have some of these long term studies that look at what individual animals do I just have a vague recollection from more than four years ago of like Dr. Shoot from URI clipping toes and of course you're limited to well yeah well that was the standard thing clipping toes but amphibians regrow their toes so that doesn't work amphibians are amazing they can regrow a limb if they lose a limb they can regrow an entire limb some salamanders have been known to regrow eyes if they get an eye damaged regrow their tails in fact some salamanders have a anti-predator mechanism that it drops its tail and its tail will sit there wiggling while the salamander sort of slithers away and the predator grabs the tail and then they grow in detail so yeah clipping the toes that works for one season oh because what I remembered him talking about was that he had determined that not only did the breeding adults return to the same pond but that he had buried hands so that they actually would fall in the exact same pond from year to year so how could he unless he's able to you know the next year reclip it or see that it hasn't regrown fully I don't know how quickly that will regrow but they will regrow there okay because I never read this study myself but I just remember him talking about it yeah and it is remarkable they will often enter the pool and exit the pool in the same spot many of my study animals entered the pool I caught it exiting the pool in the same place they entered the other way that people are identifying spotted salamanders now is just taking a photograph of their spot pattern and then using software to analyze that spot pattern and give it a unique code and then the next year they photograph all their salamanders and run through the software and it will tell you if you have matches so that works great digital photography that's pretty easy to do we have Wood and Hillside Planner house there's a drone pool that the utility company has on their maps as well we've always seen that they're 20 years and lots of wood frogs and behaviors and clearly wood frogs and the duck noise last year and this year it's wood frogs and what would cause that do they some event or yeah I mean it could have been a die off event more likely from one of the diseases there's two particular diseases that can affect wood frog the rhino virus is the one that's known to be in Vermont but I don't think we know I don't think anybody's found any huge die offs but it mostly affects the tadpoles so I wouldn't expect to complete you know population loss or one season of adults it's usually it affects the rhino virus affects the tadpoles the tadpoles don't survive to metamorphose and then the other one is the fungus Kittred fungus that does affect the adults don't think we know of any examples of Kittred in Vermont pretty sure it hasn't been found in the northeast Kittred is the the culprit for losing a lot of our tropical frogs 20 years ago there was a big thing about the frogs in Costa Rica disappearing that was when Kittred was discovered so other than that I can't think of a predatory event that would cause an entire breeding population it was on fiber I mean it was like I could see a decline in a lower number are they ever later than the gamers because like we have both and they usually were around the same time maybe they haven't been started by now I should have started by now we still see that young frogs in the summer in like in Vermont and around but I don't see as many of them later as I used to I used to see hundreds of them I don't see as many do turkeys for a date our whole 14 acres is scratched up every fall yeah they'll definitely especially for the adults too but I can't see a predator wiping out every last you know the other thing to keep in mind with these frogs that use that super cooling or the freezing overwintering strategy there's two other keepers do it as well in grade tree frogs use the same exact strategy for overwintering that only protects them down to about 20 degrees so they still need snow cover for insulation so if we get with climate change if we get winters where we don't have snow cover or we don't have deep snow cover and we get a really cold couple of nights we can have large mortality of those frogs because they're not protected they're only under the leaf litter and they might be two inches in the soil not a lot of insulation there so they might be able to withstand a night down to 10 degrees without snow cover but much below that is that to have migrated in like I mean over time find that spot again yeah some stochastic event wiped out that whole population I mean thank you for being recolonized fairly quickly frogs are pretty good at that well thanks a lot everybody enjoy the discussion