Monster Muleys Podcast
All aspects of western hunting, with a focus on mule deer.
Monster Muleys Podcast
Episode 5: The Science of Mule Deer with Randy Larsen
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In this episode of the Monster Muleys Podcast, host Shane Rasmussen sits down with Randy Larsen, a professor at BYU who has spent decades studying mule deer and their behavior. Through years of research, Randy has become one of the leading experts on mule deer ecology and has played a significant role in helping shape mule deer management decisions in Utah.
Shane and Randy discuss the science behind managing mule deer populations, how GPS collar data has transformed researchers' understanding of deer movement and survival, and what that information means for hunters and conservationists alike. They also explore the challenges facing mule deer today, including habitat, migration, predation, and the factors that influence herd health across the West.
Whether you're a dedicated mule deer hunter, a wildlife enthusiast, or simply interested in the science behind wildlife management, this episode offers fascinating insights from one of the foremost experts in the field.
Also, listen for a chance to win free digi-scoping gear from Ollin. Check them out at https://www.ollin.co
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All right, welcome to the Monster Mulies Podcast. Today we have on Randy Larson. But before we get started, I want to give you a quick reminder. Um, and also you have a shot to win a free all-in digiscoping system for your binoculars or buying a harness. So here's how you're gonna do it. You have to be a member of Monster Muleys. So go create account if you haven't, monstermulies.com, and you're gonna have to go under the Monster Mulies podcast forum. Um I will have a thread that has Randy's Randy Larson's podcast on it. Um you have to make a remark, leave a comment, ask a question on that thread. Then what we'll do is go through a random number generator and select one person that made a comment for the digiscoping spotting scope setup and another one for the bino for the bino uh digiscoping setup. Anyways, very slick quick system. Uh make sure you go register to be a member of Monster Muleys, tons of knowledge on there. If you're into big game, especially Mule Deer, you're gonna want to be on that forum. Um, I've learned so much, people willing to help. I know you know some of these magazines you sign up for, you can call and they'll give you a list of people to call. And I mean that's costing you hundreds of dollars. Get on Monster Muleys, get to know some people, um, they'll help you out, send them a private message, try to not spot burn. But yeah, um get on there, it's it's awesome. And also at allin.com, now until July 31st, you can save 22% by using code MMPodcast All Caps. MM Podcast All Caps. So check that out. Scouting season, you're gonna want to get those bucks and bowls on film. Um, anyways, we got Randy Larson. Randy is very knowledgeable with Mule Deer, he's a professor at BYU, instrumental in decisions made on mule deer hunting around the state of Utah, very um involved in the collar data, and just knows a ton about mule deer. You're gonna love this episode. All right, let's get started. All right, welcome to the Monster Mulies Podcast. Today I got on Randy Larson. Randy's very knowledgeable about mule deer, plays a big role in the collar data, and um love hearing him talk, he's super knowledgeable. So we'll just get started. Randy, tell us a little bit about you and maybe your role you play with deer in Utah.
SPEAKER_05Uh, you bet. Thanks for having me. Fun to be on. Um give you just a little bit of background. Uh uh my mom's from Portland, Oregon. My dad grew up in Cleveland, Utah. So super different uh backgrounds from mom and dad. Uh they uh got married and settled in Oram, Utah. So I'm a native of Utah, grew up in Oram. And all throughout my childhood and early teen years, hunting and fishing and outdoor stuff was was my favorite thing to do. I loved it all. Um we've hunted, and dad grew up hunting on the on the in central Utah on the Manti unit, one of the general season units in Utah, and I've done that for my entire life since I was, you know, whatever, early enough, young enough to tag along with dad, probably eight years old to now. Um I ended up at first I thought I was gonna maybe be an accountant, so I took a couple years of schooling in accountancy and just hated it. Uh switched over after a few years to wildlife biology, uh, finished up uh both a bachelor's and a master's degree at BYU, and then I went to Utah State University in Logan, Utah, and earned a PhD uh at that institution. And then I've been was hired uh right out of PhD by BYU, and I've been here at BYU since 2008, and work a lot with Brock McMillan. We kind of run a joint lab uh where we interface a lot with the federal and state agencies, do a lot of work with Utah Division of Wildlife Resources, Mule Deer Foundation, Sportsman for Fish and Wildlife, etc. And uh we love mule deer, all things mule deer. Still my favorite species to interact with and hunt. And so we're really passionate, like all your listeners are about mule deer, and are just grateful to be plugged into Utah's got a really big mule deer initiative, monitoring effort, lots of GPS callers, lots of work to try and understand what's limiting different herds and why certain herds aren't growing. And we're just fortunate to be plugged in and training the next generation of wildlife biologists in terms of our students. And so we've been doing really heavily involved with all things mule dare in Utah since about the early 2010s or so.
SPEAKER_01All right. Well, thank yeah, thanks. So I I want to be the first to say so I I appreciate all the work you guys do, and I've noticed uh you guys are you guys are quick to act, and um it's not a long drawn-out process. I mean, you if you guys think something needs to be done, it seems like you can make it happen. Um, I love the dat the color data. I mean, you're able to tell if it's a mountain lion kill, if it's a roadkill, if it's starvation, you know, if it's a mountain lion kill, maybe we need to knock down the mountain lion numbers. Anyways, I love all the color data and the work you're doing. And hunters are hard to make happy. We want to draw every year and we want monster bucks, so it's hard. So yeah.
SPEAKER_05Uh more bigger bucks hunting every year. That's what we all want.
SPEAKER_01Yeah, that's what we all want. It's it's just impossible at times. And that's cool. You mentioned your dad, you hunt with your dad, is your dad still hunting?
SPEAKER_05Yeah, he's getting up there in years now, so uh it's tough to get up in the steep stuff where we used to go a lot, but he's still active. Uh we've got one tag. My son's got a tag this year, and uh my dad will still will tag along. He'll he'll be a little bit of a spotter for us, probably. And uh we'll get out there and enjoy the enjoy the hunt. Nothing better. How old is your dad? He's uh just uh like 72-ish, I think.
SPEAKER_01Okay, I like hearing these stories of people that are a little older hunting because you know it makes me feel like my career still got some time, so I love hearing those stories.
SPEAKER_05Age is just a number.
SPEAKER_01That's right. All right, well, thanks, Randy. So, yeah, I got a couple questions for you here. And um, anyways, we'll just jump into them. Some of the listeners on uh Monster Mule submitted some questions, and I had some of my own. And so I had a couple people, they wanted to know um, does grazing cows and sheep does it impact deer and elk and does it have any beneficial effect? And do um the second part of that is does wildlife avoid areas that have cows or sheep on it? Do they compete for the same food?
SPEAKER_05Yeah, yeah, good question, great question. Um, like lots of the stuff we'll talk about and think about today, there's not always the you know, the easy, short, simple answers. Um in in general, it's to me, uh you know, my opinion would be uh grazing done well is helpful to landscapes.
SPEAKER_00Okay.
SPEAKER_05Um there's there's one line of thought, if you think about the history of mule deer, you know, think about the boom years and the boom decades when we had deer coming out our ears. Uh, you know, you're talking about the 1930s, 40s, and 1950s. There's one line of thought that grazing and even in some ways over-grazing of grass promoted shrubs, which uh perhaps benefited mule deer. Now, there's lots of other potential reasons for those boom years, including management of predators, etc. But to me, uh a good grazing plan is completely consistent with good land management in healthy herds of wildlife, healthy populations of wildlife. All right. Now you can flip that if it's if it's done poorly, right? If you're talking about you know overgrazing or poor grazing management practices that you can do harm to landscapes and that can be detrimental, but I I think they can be compatible when uh they're done well.
SPEAKER_01Okay, nice. Um, and then as you know, around the state, we got some pretty big fires going. Um, I had some uh members on the podcast interested. Um if those wildfires are they are they killing animals or just displacing them? Or what are your thoughts on that?
SPEAKER_05Yeah, good. No, and we've got data on that kind of thing. Um, in general, I'm gonna be someone who is pro-fire, especially high elevation fire. So when we when we get fires that are burning up in conifer and aspen communities, to me, those are almost always beneficial for Mule Deer in the in the medium and long term. Now, sometimes there are short-term impacts. Uh a few years ago, and it and and the fires this year are possibly in that category too, because they're burning in June, right? We've got brand new baby fawns. Uh, most of the fawns in Utah and and much of the western U.S. will be born in the month of June. So you've got brand new baby fawns on the ground. They can't always get out of the way of those fast-moving fires. But in terms of the adults, the adult females, which is the core of your sort of population, most of those will either move out of the way and come right back, or some of them will kind of just move away from where the fire burns. But you you typically do not see fire-related mortality of the adults, you know, cohort, the adults uh segment of your population. And like the two big fires in Utah, uh, we've got a lot of deer with collars on the on the Babylon fire down on the San Juan Elk Ridge. And we haven't had any collared animals die. Last year with the big Monroe Canyon fire, we had a lot of GPS collars online, and we didn't have any of the adult fem, you know, adult females or you know, year-old uh bucks and does die from the immediate fire. So, in general, I don't think we need to worry that much about direct mortality of the adults.
SPEAKER_00Okay.
SPEAKER_05Now, if you've got a 10-day-old fawn, yeah, that's a different story. Um, about I can't remember when the Bryanhead fire burned, maybe five, six years ago, the Bryanhead fire. We did see a reduction in the Fondo ratio that fall, but it was also a high elevation early June fire when a lot of the fawns were you know young. Uh but the populations bounce back and they can handle they can handle a hit on the on the the neonates, the young better than they can handle losing the adults.
SPEAKER_01Okay. So I was gonna one fire came to mind. Are you familiar with the Forsyth fire last year? It was down on Pine Valley. Okay, yeah, yeah. And that was a June fire. Do you remember anything about that if it would take if it took any adults or uh or if a lawn recruitment was no adults were uh died in that fire.
SPEAKER_05We we've in in all the years we've been monitoring collared deer.
SPEAKER_00Okay.
SPEAKER_05I mean, we we've I can remember a bighorn sheep or two that got stuck in some rocks and died from like the hot rocks of the fire, but I can't I can't think of a single deer that adult deer that has died with a GPS collar from the fire. Now, I know on the Monroe Canyon fire there were a few non-collar deer that like maybe died of smoke inhalation uh and were reported. But in general, the wildlife, unless those fires, the literature kind of suggests the fire needs to be spotting out ahead of itself, like a half a mile or more uh to where it's trapping animals in between the main flame wall and where the embers jump out ahead of it. And so to get that kind of I mean, we've got big fires with heavy wind, but in general, the animals do okay, other than you know, newborn fawns are gonna struggle to get out of the way.
SPEAKER_01Okay. How um how is well here's a question How long after a fire can it be beneficial to deer? Can it be that next spring, next summer, or is it usually a couple years out?
SPEAKER_05Yeah, um depends on where where the fires at, right? We we worry a lot about the loss of sagebrush at lower elevation. And those fires, you know, you think about the in Utah this year, we've got the one out by Eureka in the West Desert, right? That one's probably gonna struggle to come back really quickly and produce uh good, you know, quality deer habitat. But the stuff at high elevation, though it just seems to be lower risk in terms of plant community changes. Um, you don't have you know as much tea grass up at the top of those at those higher elevations, and the plant communities seem to respond better. Uh, it can be a year or two before you really get the best nutritional pulse, but you're talking about taking a whole bunch of nutrition, nutrients, minerals, taking it out of the forest canopy where it was not available to mule deer, putting it into the soil, starting over with the plants, and making and those plants are now like in the browse zone where deer can actually access them. And so, in general, I think most of these, especially the high elevation fires, are long-term beneficial for mule deer. And even, you know, if your listeners are, you know, I'm assuming most of your listeners are looking for big bucks or interested in big antlers. Fire, you know, you think about the Henry Mountains in Utah, that has been really good, especially after those big fires that that uh occurred on that mountain. I wouldn't be surprised, Shane, if we see like the San Juan Elk Ridge fire. If that San Juan Elk Ridge becomes kind of like the new Henry Mountains where you're shooting giant buck deer in three, four, five years because of the enhanced nutrition associated with what the fires are doing.
SPEAKER_01Well, there's a little nugget for all you guys. We'll keep that between me and you, Randy. We won't tell anyone about that. Yeah. Um, so even that next year, though, it's worth maybe checking the area out.
SPEAKER_05Yeah, I wouldn't high elevation. Yeah, I wouldn't I wouldn't avoid areas that have burned. Um I we hunt on the Manti and had a big fire burn through the spots we hunt. And I remember the first year shooting a good buck out of a bed uh on recently burned landscape, right? Most of the time uh there's pockets and refuge that doesn't burn, you know, there's still some cover for them, and so yeah, I wouldn't I would not necessarily avoid hunting recently burned areas.
SPEAKER_01Awesome. All right. How how is the fawn recruit recruitment looking across the state this year? Do you know? I mean, I know it's been super dry, but yeah, what have you seen?
SPEAKER_05Yeah. Um there's two parts to that piece, or you know, kind of two parts to that question. First thing that I would I think about, like survival's been pretty good in Utah, and and let's start maybe we'll start with we'll divide your deer population up into kind of three groups. There's the adult females that are at least a year and a half or older, and they came through the winter. You know, we hardly had a winter, it was really light, we didn't get very much winter kill. Um, you know, they came through the winter okay. And then the other group uh or the next group down is six-month-old fawns. So fawns from last year. We catch them in December when they're six months of age, and they off often only half of them make it, like the long-term average for overwinter survival of six-month-old fawns is only like 50%. But this year, because of the light winter, we've got really good fawn survival. Uh, we're running as good as we've been in Utah. Um, you know, we're kind of at the above average uh for survival of six-month-olds. And then the next the latest piece or the last group would be fawns that are born this year. Um, they won't really show up as huntable deer until they're you know, a year from this fall when they're yearlings, two points spikes. Um that's TBD, sort of, right? They just were born most of them in June. Um, we are in bad drought, which is not good. Me personally, after doing all this work and you know, spending a lifetime thinking about them and looking at them, I'd way rather have a big winter than a bad drought because the winter is going to put the moisture back into the landscape, into the soil, into the habitat. But I I got my fingers and toes crossed, Shane. The latest forecast for the southwestern U.S. is above average precipitation and a reduction in the drought due to monsoon moisture. So July, August, and September are supposed to be wetter than average. How accurate is that report usually uh I mean it's it's a prediction from it's from NOAA. You know, you listeners could go look it up and just Google NOAA, so the National Oceanic and Atmospheric Administration, they put kind of a three-month forecast out.
SPEAKER_00Okay.
SPEAKER_05And because of the big El Nino out in the Pacific, their prediction is that we're gonna get a really kind of juicy thunderstorm season this summer with lots of monsoon moisture. And if that happens, that's like the perfect combination, right? To grow deer. We've had a light winter, and now if we get excess moisture and increased moisture during summer, we're growing deer. We're gonna be, you know, females will be fat, fawn survival will be good this summer, fall, the animals will be healthy going into this next winter. So that at least in the forecast, the recipe is good. Everybody cross your fingers, cross your toes, say your prayers, whatever. We hope it comes to fruition. Uh, but yeah, I think we're in an okay spot. Drought is not good, but if we get relief this summer with monsoon moisture, we will be doing okay.
SPEAKER_01Awesome. Here's a question I've been dying to ask, and I've heard a couple different thoughts on it. So, anyways, let's say this year's bucks, they're um anyway, they're who knows, they're like probably 80%, 75%, 80% growing right now. Say they get, I guess, is it already written? Is there are there antlers, is it is it already written in their their body? It's like say we get a big storm in a few days, a week. Is that gonna help the antlers much, or is it like no, what's done is done?
SPEAKER_05Yeah, I mean, as we get closer and closer to the those when they stop growing them, I think you get it, it gets uh more written in stone.
SPEAKER_01So maybe like a May or June storms are gonna they still will help them this year, but not not maybe all right.
SPEAKER_05Yeah, I think a lot of the antlers, the antlers, it would be how well they have come through winter and then what the spring looks like. Um, but there's a lot of stuff up high, at least in Utah, that to me is not you know, is looking okay in terms of vegetation. There's the low stuff isn't great, and certainly parts of southern Utah are you know it's pretty bad drought. Um so to me it what's it's it's mostly written what they're gonna be, is especially as we get into mid-July ish. Okay.
SPEAKER_01Okay. Um, have you had any color data that's uh deer deer drying from drought in southern Utah this year?
SPEAKER_05No, we've uh we've had a we had a few come in this week uh that look like they are potentially diseased. So one of the main diseases that happens in the summer is EHD, and that's uh epizootic hemorrhagic disease. It's it's transmitted by midges that bite deer, especially when they concentrate at water. So you see a little bit of a pulse in drought years with EHD, but not so much yet this year, just a couple individuals in that category so far.
SPEAKER_01Well, cool. All right. Um, another question. What percent of deer say we have an a unit with 18 to 20 uh bucks per dose per hundred dose? What do you is there any data or any knowledge um on what percent would be three and a half and older?
SPEAKER_05That's a great question. Um it depends a lot on what the previous years uh fawn survival's been. So the the six month olds how many of the six month olds made it through that first winter their first winter and then are available to harvest as like yearly uh spikes and and yearling two points and in good survival years you have a pulse of yearling bucks available that fall that next fall which makes the percentage go up and then in bad years when the survival's not good getting through the winter you got a big winter or animals came into winter really skinny and thin and not very heavy and they struggle to make it through their first winter you don't get many year yearling bucks and the percentage that are three and older goes up as a total percentage number. So that one bounces around a lot depending on how the individual year is for those six month old fonts and whether they're going to make it to be yearling bucks to in that in that group if that makes sense. Yeah okay um no go ahead I do think and your listeners will know this as well as anyone uh even at 18 to 20 or even 15 to 17 bucks per hundred dose there's usually always good bucks still available for people that are really good hunters and know where to go and go back you know maybe away from some of the crowds get in the backcountry a little bit you can still turn up those big bucks and you see it all every year you know on social media someone will kill a really big giant buck off a general season unit that's got a relatively low buck dough ratio. Yeah all right so no really hard data or anything on if out of those 17 18 bucks per hundred dollars if there's like two or three that are no real hard data on that all right yeah no hard data and and what I would one of the things that I've sort of come to grips with we're always trying to kind of manage things uh to be consistent and I and I sometimes think we we ought to maybe try to take advantage the populations are going up and down all the time a lot of that's associated with the weather and to think you know oh let's just got it kind of it's going it's trending in the right direction let's just save them we next year's gonna be phenomenal two years from now it could be phenomenal that's true but you might have something happen in between the that now and then two or three years from now and so I I sometimes wish we could be more responsive in how we think about hunting and when when you've got them and and it's been you know a couple good years in a row maybe we we harvest them right in instead of always trying to save them or bank them because it's hard to save them long term.
SPEAKER_01Okay yeah um all right here's another question I've been dying to ask you so say you're hunting a unit where the deer migrate oh I don't know so let's just say mid-Octoberish um if those deer are getting pressure say they're still somewhat in the high country and like I mean this could be the case in Wyoming some units in Utah if they start getting pressure will that pressure cause them to migrate earlier or no?
SPEAKER_05Yeah that's a great question this the things that I've looked at and that we've looked at with collar data the migration stuff is fascinating and it's not always predictable you'll see some places where almost all the deer migrate uh like the Utah's Ponsagant unit for example almost most of the deer on that Ponsagant unit are migratory and they you know they spend the winter down on the Arizona Utah border they migrate back up uh you know on top of the Ponsagant during the summer then there'll be other places like you think about like the cash unit in Utah northern Utah I don't know maybe 50% of deer are migratory and the other 50% are are like resident deer and so it's really there's a lot of variation one unit to the next and then on top of that there's in like in deer are just individuals right and they're all doing their own thing and there's some of them that do something you know and and others that are doing other things and they're everybody's just an individual in that population. In general though deer to me are way less responsive to human pressure than elk elk they you can move them around with pressure and they'll seek refuge on private land or they'll move big distances due to human presence and hunting pressure. Deer everything I've looked at suggests they mostly are sort of hunkering down and keeping to their normal pattern their normal area but maybe adjusting when they're out you know maybe they're a little more nocturnal with some increased pressure but not necess we're not necessarily changing their migratory behavior. Okay. That's what I mean there could be places where it does happen but the stuff that I've looked at they seem to be much more uh are much less responsive than elk to hunting pressure.
SPEAKER_01Yeah that's that's a couple people I've talked to they're like the thought is the similar what you just said they just tighten up their pattern they're not gonna leave the country maybe maybe they you know drop 500 feet a thousand feet but they're not gonna head yeah seven eight miles fifty miles whatever yeah I think that's right and I think they get harder to find they're smart they can feel the pressure and they maybe go nocturnal a bit on you those kind of things but they're not the hunting pressure is probably not what's forcing most of them to migrate early you know they're not migrating earlier or leaving for winter range any earlier due to pressure I don't think most of them good yeah thanks for that yeah um so that you guys did one study I th there I think there was over a thousand bucks and it might have been I believe this was you yeah it was on a like CWMU tightly controlled private land and you guys took data on how big the bucks were correct yeah now was it every buck that was shot or bucks over a certain age or only mature bucks or it was every buck?
SPEAKER_05Yeah no so uh the what you're referencing there so Brock McMillan and I here at BOU we uh and just throw this out to your listeners too if they ever want to get an animal aged we can we can take the teeth in and we can send them through a process here where you can count the growth rings and see with pretty high accuracy how old they are.
SPEAKER_00Okay.
SPEAKER_05And we've been doing that for a long time in conjunction with the state agencies as well as a lot of private land owners and where would they send the teeth Randy uh what's that where would they send the teeth in? Oh they can just get a hold of me and we and we can take them here at BYU okay cool we've got a lab set up that will process teeth there's multiple labs around the country uh but people yada you know it's kind of makes it it adds an element of fun kind of enriches your experience to understand how old that buck you killed is right yeah so we've there's a big data set that's been collected because of that a lot of times the big chunks of private land are trying to manage for trophy opportunity and they're interested in the average ages of the animals harvested and so the study you're referencing we colle we collected uh over about 20 plus years a whole bunch of ages and boon and crockett scores for both deer and elk that had been harvested predominantly on private land CWMUs in Utah um you know big ranches in Montana uh some of the tribal ground in Arizona etc and we collected all of those ages uh we had an associated boon and crockett score and we're looking at what a couple things but what's you know average a or average score for the various ages it's pretty interesting you can be giant by giant I mean 200 plus inches on the boon and crockett score to even 220 230 you can be absolutely giant at four and a half and there are lots of really big deer that are only four and a half when they're killed and then it kind of plateaus after that you you get a little bit more mass as you you age up but your overall score doesn't really increase that much as you get past five six into the seven eight year old nine year old age age classes yeah so you know age is really important for for size especially during those first three or four years and then after four years of age uh you don't really get all that much bigger yeah it was that's the average Shane right so I'm talking about the average of a large sample anyone and everyone could look at you know pictures from the same animal year to year and say oh man it shrunk this year or it blew up this year. So there's individual deer getting smaller or bigger you know with each successive year. But on average the old you know you're increasing by a whole bunch through about age four and then after four years old average size average boon and crock score doesn't increase that much with age.
SPEAKER_01Yeah I think it was like four and a half or either ninety or ninety I think it was ninety five percent grown yeah yeah like something like ninety three percent of their potential average max score.
SPEAKER_05Okay.
SPEAKER_01Now again that's averages and I can think of um we worked with DWR and collared a really big buck down on the uh in southern Utah and that thing he had an ear tag and he had the collar so you could you know you could you could see him every year and have pictures uh of him for four different years and that that one in particular was bouncing around like crazy some years he was a what 180 plus excuse me a 180 plus buck other years it'd be kind of regressed in a drought to like a three three point that wasn't that big so he bounced around a lot but but on average that that pattern seems to hold from across most of the western US was he a low elevation deer into drought point at all down yep down in Pinion Juniper sagebrush desert country okay so real real subject to precept changes you know drought years and wet years yeah and on that study I think it the average of like selective hunters on private land trying to shoot big bucks um being picky didn't it come out at about 170 yeah even a little less like in the mid-160s mid-160s okay so there's a lot of deer that that's their top end yeah like their top end is a 160 inch four point right uh and so if you're looking at a big buck and when I say big I mean you're looking at a big saggy belly big body size that that's probably a you know five year old or older buck and he might only be 160 inches on the boon and crockett score and that's kind of maybe his top end and there's a whole bunch like that yep and there's probably more of those well I mean that's the average right that's the average kind of max score and so there's gonna be a lot more of those than there are going to be the 215 inch 210 inch bucks right those those are kind of the the ones that are rare. Yeah yeah um any idea then this may just be anecdotal are you guessing from your years of experience um any idea on public land what percent of bucks will hit 170 or not is that hard to know I mean I'm guessing it's pretty hard to know but yeah it's pretty hard to know if they if you on average I you know you're you're gonna be about 165 as a top end and you're probably gonna get to that by five years old.
SPEAKER_05So if you've got some age structure in the populations then the average five year old buck is probably 150 160 kind of thing. And there'd be some that would be smaller that would never get any bigger you know they might be these some of those forcas kind of deer that people talk about or see and take pictures of or you know on the other side of it would be the real big ones that are 200 plus inches.
SPEAKER_01So I know it seems like um what the data is showing is that around 15 16 bucks per 100 dose is the best number to grow a population correct or yeah so this is some new stuff and it's in a lot of ways Shane I wish it went the other way I know that like this is not the funnest stuff to think about right because we all want more bigger bucks uh and the the data come in from two sources that I think are pretty reliable one is uh some kind of natural experiments that happened in Colorado if you look at the history of how Colorado's managed their buck doe ratios they've they've increased the you know the buckdo ratios in Colorado now are pretty high relative to you know maybe Idaho or Utah in general and if you look at the Fondo ratios associated with those over long time spans you see a negative interaction as the buckdo ratios increase the fondo ratios decrease and so you're in some ways you're trading bucks for fawns a little bit um and then the piece that's most recent that supports that is the same pattern in Utah but also maybe a mechanism for it and the mechanism is we see skinnier female mule deer adult females adult does are skinnier when they are caught captured and measured with an ultrasound on units that have a high buckdo ratio suggesting that maybe there's some competition between the bucks and the does maybe there's potentially other things going on but if you're gonna run a high buckdo ratio which a lot of us want right we want to have lots of bucks we want to see a lot of bucks we want to be able to select and pick five six seven year old bucks that have big antlers and there's more of those in a population if you're running a high buckdo ratio but if we're gonna do that we're just gonna trade off and we're gonna expect or have lower production like our Fondo ratio is going to be lower.
SPEAKER_05And when we you know to me it's just a little bit of a trade off with what we want um it's not again it's not the funnest thing to think about like it'd be nice to have it go the other way where higher buckdo ratio led to higher fawn recruitment you know production but it doesn't go that way the pattern in general is units that have a high buck doe ratio usually have lower FONDO ratios and so if you want to try and balance that you know that's tough uh because you've got people that want trophy units you got people that want to hunt every year um but you know the where Utah's landed I think is pretty consistent with the data. If you're gonna have a general season hunting opportunity where we're not managing specifically for trophies then somewhere around 15 to 20 bucks per hundred dose kind of ensures that you've got pretty good production and there's still going to be some mature bucks in the population for people who want to work hard and hunt hard and look for those.
SPEAKER_01Okay yeah no I don't envy your guys' job it's a hard deal and so I know and I don't know anyways I know like states so I know Wyoming they're averaging around 30 bucks per 100 dose say region G region H and that deer herd's growing um would you say it's possible to grow them with higher buck to dough is just slower or and I think there's some places in Nevada or it's just yeah what are your thoughts on that?
SPEAKER_05Yeah no it's you can still grow and and when we did this analysis we we put into the analysis a whole bunch of things like snowfall snow depth uh precipitation and by far and away precip is the biggest driver so if you're getting you know you're going through the winter it's not a catastrophically bad winter and you're getting normal precip patterns you can still grow deer even with a high buckdoh ratio especially like in Wyoming region G, region H, they had that really big winter of 22 23, they're kind of bouncing back from that and and those populations undoubtedly are growing even with perhaps a higher buckdo ratio but if you after accounting for those things which again are the most important in terms of growing deer the weather the things we can't control after accounting for all those things then it looks like there's a negative drag on population growth with high buck dough ratio. And so again it's it's not the funnest thing to think about but the one thing we can control or have some influence over is how many we harvest and what you know what that post hunt buck dough ratio is there it does seem like if we're managing lower than 30 maybe around 20 even getting down into that 15 ish range that that's going to be a little bit helpful on how heavy the fawns are how well they survive their first winter and how fat the adult females are okay so that's yeah you but you can still grow when conditions are good. And what I tell people all the time like even private landowners like it's the data are the data it's not meant to be in any way critical of what people are doing right we're not gonna change how we manage the Henry Mountains right we're not gonna turn the Henry Mountains into some kind of general season unit right we're gonna keep we're gonna keep trophy units out there. If I own private land I would manage for a higher buck dough ratio I just would yeah but I would do that knowing that I'm gonna probably have on average over the long term maybe lower production and lower fondo ratios than if I manage for 15 to 17 bucks per hundred those.
SPEAKER_01Yeah and I guess the problem I mean of course like you know big buck trophy hunters are gonna want they're gonna want 40 bucks per 100 o's and then you got people that can't draw tag they're gonna want you know 15 bucks per 100 O's and so I guess yeah so so Utah's probably settled more on the opportunity it would cut tags quite a bit if they jumped them up the buck to dough.
SPEAKER_05Yeah I mean to me Utah's got a pretty good balance right we've got a bunch of limited entry hunting opportunities they're not the easiest to draw some of them take forever to draw um and then we've got our general season opportunities and so it's a tough balance for the state of Utah to try to manage that to try to satisfy everybody out there but it's a little it's a little bit uh pie in the sky to hope that we could manage for 40 or 50 bucks per hundred dose and not have any impact on the overall population and you know if you had livestock right I I think the livestock uh analogies are pretty good. If you had you know if your pastures could support a thousand cows and you're trying to to to produce cattle to sell and and you're you're trying to make a living how many bulls would you run with those thousand you know of those thousand cows you know you'd have a small number and we yeah 15 we see zero impact on pregnancy like almost all the adult females will get pregnant almost all of the fawns will be born in June even when the buck doe ratios are down in that twelve, fourteen, fifteen to twenty range.
SPEAKER_01So okay so they're still getting Brad on time with those Oh sorry Randy you got me? No you're good. Sorry hit the dang mute button again. Um so Perfect. Um, so even there even with those uh buck to dough ratios around the 15, 16, they're still getting bred on time. And yes. Okay. Yeah. All right.
SPEAKER_05They're still getting bred on time. And there's two, there's two potential speaking to that that same idea. Um you know, you'll have uh when we capture adult females, does, in December, they are skinnier coming off of units that have high buckdown ratio. And there's two lines of thought there. One is maybe the bucks are eating some of the same food that would be available to the does. And so that might be part of why they're skinnier. The other potential idea is if you're a f adult female in estrus in a high buckdor ratio unit, maybe you get harassed more by males during breeding season, during the rut. And so, you know, your month of November, you're you're being harassed kind of almost like maybe constantly, and your your fat accumulation is then lower. Uh, that's another potential explanation for that. Um and you can just, you know, you can yeah, your listeners could do this, just think about, you know. I like to think about in Utah, just pick two adjacent units, and they're they're never exactly the same. There's always some differences between them, but you could just go around the state and you could say, okay, let's pick the Poncigon and compare it to the Penguinch Lake. Poncygon is obviously a premium trophy unit with a high buck doe ratio. Penguich Lake is a general season unit. If you look back through 30 years of data, on average, Fondo ratios are going to be higher on the Penguinch Lakes than they are on the Poncygon. Now, maybe that's a predator issue, maybe it's a habitat issue, but it's just how it's gonna be. If you looked around Utah and you said which of our units has the very lowest uh fondo ratios on Analope Island, that's the one in Utah. And that's also the one that has the very highest buckdo ratios, and so you could just you know, if you did the same thing in a similar state, another you know, adjacent state, I'm sure it should it pan out the same way. There's just a negative interaction there again. Personally, I wish it went the other way. I wish it was positive, but it's not.
SPEAKER_01Yeah. On Antelope Island, is the how is the feed out there I mean compared to other units, is it how is the feed on Antelope Island? Is it average, not not great?
SPEAKER_03Yeah.
SPEAKER_05Um that's a really good question. Certainly, you know, if someone came to me and said, you know, I'm I'm interested in mule deer, I want you to show me the best mule deer habitat in the state of Utah. And I said, Okay, let me think about that. I probably would not pick animal pilot.
SPEAKER_01I've heard it's a got a big cheat grass problem, is that true?
SPEAKER_05Yeah, there's a lot of cheat grass there. There's a lot of threon, which is another uh grass that we don't love. Um, but that said, they the lake moderates the winter and cheat grass when it's green uh in the spring, and then it also there's usually a fall green up, is actually pretty nutritious, it's just nutritious for a short time only. Okay, and then on Allope Island, there's also an exotic invasive forb that you'll see it in the videos. It's the it's got a yellow flower, and both mule deer and bighorn sheep love uh that big tall forb. And so that that seems to have some pretty good nutrition. Um a few years ago, we moved deer off Antelope Island because the population is getting really big, and they were really fat and healthy. So it's interesting, right? It doesn't look like maybe your quintessential mule deer habitat, but um the animals seem to do okay there uh in terms of nutrition. Um, and that's kind of an interesting thing to think about.
SPEAKER_01Yeah, that's awesome. Thanks for answering those questions. I know they're tough questions, so thank you. Um yeah, um going back to the migration, what uh what triggers migration? Is it is a I'm guessing it has something to do with their feed.
SPEAKER_05No, I think you're right. Uh what what you see, and again, there's a lot of variation there, um, and that makes it hard to unpack it and understand it. Mule deer on the Poncycan, both bucks and does, are really migratory, meaning a very high percentage of all the collared animals show these strong migration patterns, and those are interesting in that they seem to move on the calendar.
SPEAKER_00Yeah.
SPEAKER_05So whether whether it's a long drawn-out summer and it's still hot at the end of September and early October, they're still moving.
SPEAKER_01So is that when they usually move about early October on the Pontigan?
SPEAKER_05Yeah, you get you get some September, October movement there, and that that that's almost like to me what you might call obligate obligatory migr migration where they're just moving on within a day of or two of each of last year and the year before, they just go, and it doesn't really matter how much snow there is, it doesn't really matter whether the summer was hot and dry or wet and cool. Uh, and then there are others that and they do move a long distance. That probably plays into it, right? How far they have to go. And then there are others that are maybe gonna only drop down a few miles, and they will maybe wait until they're almost forced to come down because of snow.
SPEAKER_01That's what it seems like on the Wasatch front, where I hunt.
SPEAKER_05Yeah, and I think the cost to move down isn't that high, you don't have to go that far, and so you just stay up high where the good food is as long as you can, and then all of a sudden you get a big storming, and oh, time to go.
SPEAKER_01And those book cliffs bucks seem to they seem to move by calendar too, yeah.
SPEAKER_05Yeah, more more like the Pontigan, more calendar type movement, yeah.
SPEAKER_01Possibly a little later in uh in October or Yep, yeah I think so. Yeah, I think so too. Awesome.
SPEAKER_05So each of the each of the each herd unit will be different. I'll bet if you moved over like the some of the longest migrations, the longest known migrations in the world are for Mueller in Wyoming. And I'll bet those are because they're going so far. I would I don't know if uh personally, but I would imagine those are more calendar type movements, too.
SPEAKER_01Yeah, that I've never even thought about that of how far they got to move. I'm sure that plays a role. And then as far as the rut, um triggering the rut, um I've always heard it's has to do with the sunlight period. And I mean, so I I've seen Bucks, I don't know, I mean I've seen them run October 24th, October 25th. But Clist comes to mind on that again. They seem like they always are rutting early, and then yeah, and then and then so I mean, how much effect does snow and cold weather really have on it? Is it is it really kicking it forward, or are they just more visible, or what are your thoughts on that?
SPEAKER_05Yeah, that's a great question. That's something like Brock McMillan is pretty fascinated in here with that BYU trying to understand that. And how much of it is driven by the males, the bucks, versus the females? Yeah, and so a lot of times the thought is uh females will come into Estrus, and then you know the bucks are gonna be ready to go. Uh, there's a lot more investment in offspring on the female side, right? Females are going to raise the babies in utero, and then they're gonna nurse them. And so there's way more female investment for most mammals uh than there is investment from the males in terms of energy. Um, there's multiple lines of thought on the timing of the rut. It does look like it moves, like it'll vary one year to the next by you know, up to a week or so. And and then when we do the research where we're catching the baby fawns, you know, we're the mean birthday is also moving as much as like a week. Uh, most of the literature suggests they don't change the gestation length. So once they get pregnant, it's gonna be uh about 270 days or so until they give birth. Uh but the when they get pregnant, when the peak rut is that's moving around uh by as much as a week, a year. Um what drives it? Is it the moon, lunar phase? Is it the nutrition of the females? Does look like when there's when the females are fatter that the the peak rut is maybe a little earlier, like they come into estrus a little bit earlier, but there's still lots to unpack there. We've been hunting them for so long, and we and we've been so fascinated with deer forever, but there's still surprisingly enough, a lot to try and understand about what is associated with the changes that we see in that peak rut and peak birth.
SPEAKER_01All right, interesting. Well, Randy, I know the listeners on MM are gonna love this information. My favorite podcast, some of my favorite are the ones with you guys that are, you know, just the biologist type stuff. I'd love that. So, anyways, thank you so much for joining us.
SPEAKER_05Anything else you'd want to say or no, it's you know, thanks for having me. It's uh I like the podcast format. Uh, I think it's a good format, a way to try and engage with people. Get out and enjoy it, you know. Prep, you know, this especially this fall, those of you who are lucky enough to have permits in your pockets. Uh, the older I get, the more valuable those seem to be to me. So I'd tell your listeners to just get out and enjoy it. Um you know, you can enrich your experience. Antlers are awesome, and everyone wants to shoot a 200-inch buck. I killed one. Uh my all one of my all-time favorite experiences in my life was hunting the mantai. So this is a general season unit in Utah, 15 to 17 bucks per hundred dose. My friends and I packed in a long ways into the backcountry, and we ended up shooting a deer. It was a 30-inch buck, but it had kind of regressed on the front end a little bit. It had you know what you would maybe call crab crop, uh crab claw fronts, so it only scored 167. It's about we pulled a tooth, yeah. It's a big buck, and it was 30 inches, legit 30 inches wide. We pulled a tooth and we aged it, and it came back at nine and a half. Wow, and we thought, oh my gosh, how did that thing escape hunters for nine years, lions, cars on the roads? Oh my goodness, you know, yeah, nine and a half. And you know, to this day, I've killed deer that are bigger than that in terms of score, but not better than that. So, as you think about what these trophies are for each and all of us, um, you know, pull a tooth and get an age and think about factoring that into how you assess uh what you want to harvest each year and just make sure you're enjoying it.
SPEAKER_01You know, that's a really good, really good point you make there. Uh I'll be honest, some of my favorite bucks, they're not my biggest. That's a good point. So, yeah. Well, I appreciate Randy. Um, maybe we'll have to have you on again. I love listening to you and just appreciate the knowledge you've gained that you're willing to share. So thanks so much.
SPEAKER_05Yeah, anytime happy to jump back on.
SPEAKER_04Thanks, Randy. Thanks, Jenny. Yeah, that's good.