Another Blog-tastic Year!

Barely a week left in good ole 2016.  The end of the year always arrives at an alarming rate.  Mostly because starting the week before Thanksgiving bear and deer season consume us.  Add in all the “extra” holiday duties (shopping, cookie making, cards, etc), throw in a sick pet or 2 for good measure, and it’s like riding Expedition Everest at Animal Kingdom.  I’m a bit shell shocked by the time Christmas rolls around. 

Now that I have put dead bears, deer heads, and formalin-floating brain stems behind me for another year, I thought I’d take a look back at our year on the blog.  Taking inventory, I discovered our post count (including this one) is 138!  Compare that to 2015 when we just cracked 100.  

Those posts garnered over 250,000 views!  HOLY CRAP!  Our 2016 posts were seen a quarter of a million times over the past year.  That’s not counting previous year’s posts that were read in 2016.  You can add on another 85,000+ for that.  That’s over 335,000 times one of our posts was read in 2016, almost 100,000 more views than last year.  

So what did you like best in 2016?  

Readers still loved The Life and Times of Buck 8917 (written in 2015; read over 10,000 times in 2016) and in a surprise landslide, Wind’s Surprising Effects on Deer Movement (written in 2015; read over 22,000 times in 2016!).

Here are the Top Posts written in 2016:

10.  I knew I forgot something

9.  The spice of life

8.  Closure

7. Confessions of a shed hunter

6. Average Joe

5. Like Mother, Like Son

4. Old Men

3. A Dangerous Game

2. Where did he go? And where did he come from?

1. When do they sleep?

These 10 posts accounted for almost 20% of blog traffic in 2016.  Impressive.

Since we had such a successful year, we have decided to celebrate by taking a much needed break.  We’d like to wish readers and their families a happy holiday.  We’ll be back when you flip the calendar for another year of fun!

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-Jeannine, Duane, and the rest of the blog-writing crew!

Deer Crew Diaries – Entry 47

[Comment in brackets are by Jeannine and Duane]

From the Northern Crew:

Dear deer people,

I woke up Monday morning to a winter wonderland outside. Had to brush 4 or 5 inches of snow off the PGC truck that had accumulated over the weekend. I’m fairly certain we already have more snow than we had on any given day last “winter.” Hopefully it sticks around for trapping season!Rock Run Rd

The unplowed Susquehannock roads made things interesting, but I was still able to get around without tire chains. However, I had to take that truck into the shop because some error codes started flashing on my dash. This is the same truck that has been spontaneously shutting off while driving. On that note, I’m also going to drop my third truck off on Tuesday to have them check the starter while I’m away for the holidays. Here’s to hoping for 3 road-worthy vehicles come January! [Constant vehicle woes make for interesting trapping seasons]

I spent the first half of Monday aging deer and then conducted a mortality run in the afternoon. Wednesday, I followed up with a hunter harvest in Ulysses to retrieve a doe collar. The remainder of the week involved collecting a few final fawn locations for 2016.

I will be driving down to State College next week to hand off my laptops to April for replacement and to deliver 4 GPS collars to Tess from harvested deer. Then I’m heading back to Wisconsin until the New Year [a rest before the craziness of trapping season]. See you at orientation in January!

-Hannah
Field Crew Leader
PGC Deer and Elk Section

 

From the Southern Crew:

Hi all,

It was a week for the trucks. Highlights include: moving the last of the Clover traps to Penn Nursery (SCORE!), getting new tires for my truck (YES!), getting my truck mirror fixed, and picking the crew truck up from the garage. Not to mention, I saw plenty of wildlife, including four of the collared fawns, 

12714 Fawnan American Kestrel, Yellow-bellied Sapsucker, and a raccoon.  I got a decent look at 12714’s collar and it looks to be stretched out pretty good already [the fawn collars are designed to expand as the fawn grows so we like to make sure the collar design works as planned]. 

Levi volunteered two days this week to help me haul the last 11 traps from State Game Lands 215 to Penn Nursery [newly renamed the Mira Lloyd Dock Resource Conservation Center – you really should click on the link about this woman]. I also spoke with a few landowners to gain permission for deer trapping on their properties this winter.

I will be driving the crew truck for the rest of the year while my truck goes into the garage to get inspected and to fix a possible muffler issue. This week, I started noticing a strong exhaust smell in the cab of the truck and hearing a ticking sound when I pressed down the gas pedal. The exhaust odor was overwhelming, so I visited the mechanic immediately. Both exhaust manifolds were replaced last winter, so that shouldn’t be the issue [still sounds like an exhaust manifold to me – anyone taking bets?]. My truck repairs usually have something to do with bad rust.

First thing Monday morning, I’ll gather all of the computers from the interns and Hannah to exchange with Ian for newer laptops. I plan to work in ArcMap as well, which will keep me plenty busy. Other than that, I’ll continue to monitor the fawns and get locations in my spare time.

-April
Field Crew Leader
PGC Deer and Elk Section


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Deer Crew Diaries – Entry XL…46

 

From the Northern Crew:

Dear deer people,

Monday and Tuesday of last week, I assisted PGC Forester Kyle Clouse with deer aging. He was flying through them almost faster than I could enter the data (pro status). He did, however, let me run the show at one processor. It’s definitely not as easy in real life as it was at training, but good experience nonetheless! I’ll be assisting him again on Monday. 

White out Longtoe Rd

During the remainder of the week, I gathered locations on fawns and gave the auto shop the go ahead to repair my latest truck (aka problem child). It started snowing here Thursday night and has hardly stopped since! Hopefully this weather trend continues through trapping season 🙂

 

-Hannah
Field Crew Leader

PGC Deer and Elk Section

 

From the Southern Crew:

Greetings all,

I began the week with some good old fashioned deer aging with Aaron Tyson, a PGCOld deer teeth forester. We visited 5 different deer processors in Centre County. This photo shows the teeth of an older deer we came across during aging [PGC deer agers only age to 3 age classes: 6 months, 18 months, and 30 months. But there are much older deer seen]. 

A collared fawn was harvested this week. The last live signal I received for her was Wednesday, December 7th. On Friday, I could not find her. I had no issue picking up her sibling’s collar signal though. I spent some time looking for her and contacted Tess to see if anyone had called in a harvest. Tess wasn’t sure at the time, but did confirm with me this weekend that the fawn was harvested. 

I also got back into working on the ArcMap trapping site file this week. The file isn’t complete yet, as I am having some issues with the formatting. It’s getting there though. 

A landowner also shared some photos and a video of a collared buck that was hit by a vehicle sometime in August [he appears to have made almost a full recovery]. We collared this buck just over the mountain from their place this past winter. 

-April
Field Crew Leader

PGC Deer and Elk Section

 

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Deer Crew Diaries – XLV

 

From the Northern Crew:

Dear deer people,

Last Thursday, I retrieved 2 radio collars – a harvested buck that only had one antler left and a DMAP doe. Coincidentally, both deer were captured and collared in April of 2014.

During Sunday’s mort-run, I discovered that one of the VIT fawns had moved 2 miles back to his summer home range for the first time since September! His winter range is in a heavily hunted area, so I wouldn’t be surprised if hunter activity encouraged him and his mama to take a little hiatus.

This week, I’m excited to be helping with deer aging Monday and Tuesday [she is one of the few who is “excited” about deer aging]. Aside from that, it will be business as usual monitoring fawns and following up with any harvests or mortalities.

-Hannah
Field Crew Leader
PGC Deer and Elk Section


 

From the Southern Crew:

Hi all,

I conducted two mortality investigations in Rothrock this week. A fawn on Tuesday on which I couldn’t find any obvious signs to explain cause of death.  I retrieved the carcass for the vet to necropsy. 

There was also a VIT doe mortality on Thursday. I located the carcass and found a bullet hole behind her shoulder. This does was trapped in March and her fawn(s) were born on Memorial Day.  Unfortunately, this was the only VIT deer we didn’t locate any fawns for. She was still lactating though which confirms that she still had young.  I was bummed to see the meat go to waste, but I’m sure she will be a nice meal for the scavengers. 

A landowner informed me that someone found a dead tagged buck on his property. He found 5 piles of bear scat around the carcass and thought it was an unrecovered harvest from archery season. It wasn’t recent though. We trapped the buck in a rocket net in Rothrock on March 1st, 2016. 

I also organized and inventoried the first aid kits, which then allowed me to submit my supply list. 

I’ll be assisting with deer aging and CWD sampling on Monday. I’ll be monitoring survival on Tuesday and Friday to see if we’ve lost anymore fawns during rifle season.

-April
Field Crew Leader

PGC Deer and Elk Section

 


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The Season is Almost Over

Over the past month we shared with you movies of several different bucks and then let you try to figure out when they started their crazy rutting movements.

Here’s Buck 12755 and his movements from October 1st through November 20th in 2015.

After you watch this movie you can make your best guess as to when his rut movements began. We’ll summarize the results from all 4 bucks next week. I’ve already taken a peek at your answers and I think you’ll find them pretty interesting.

Here’s the movie!

Watch this movie as many times as you like. When you think you know when this buck begins and ends his rut movements, enter your dates in the online survey. The survey will be open until 11pm on December 12, 2016.

Enter your dates here

We ended the movie on 20 November because that’s when bear season starts. Although there is still some breeding that occurs through the end of November, the bear season and rifle season have a greater influence on buck movements than finding the love of his life.

-Duane Diefenbach

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Deer Crew Diaries – Entry XLIV

 

From the Northern Crew:

Dear deer people,

I was out of town most of Thanksgiving week, so not a lot of news to report on the deer front. However, I did get a repair estimate last week for the “new” truck that was recently added to my inventory and needs inspection. Hoping to have all 3 trucks up to snuff before Christmas.

I did a mort-run on the fawns yesterday afternoon between 1:00 and 3:00PM.  Boy were the hunters out en masse! The fawns were all alive, but they had definitely altered their locations in response to the increased human presence in the woods.

Happy hunting!

-Hannah
Field Crew Leader
PGC Deer and Elk Section

 

 

——————————————————————–

From the Southern Crew:

Hi all,

This week didn’t necessarily go as I had planned [in the field, when do they ever?]. I didn’t make it to the bear check station in Beavertown on Monday. I called Matt around 4:30 PM when I was finished with fawn monitoring, and they only had checked 7 bears. Since they had enough help, I chose to skip bear check this year. I missed talking with the hunters and PGC employees, and of course, helping process the bears. Maybe next year!

Unfriendly schedules and appointments on Tuesday kept Levi and I from getting Clover traps on State Game Lands 215. Now, we are going to wait until rifle season is over to go to get them.

I struggled with getting some information together for what should have been a simple truck repair. When I wasn’t monitoring fawns or using LOAS [computer program that calculates location coordinates and stores data], I was contacting people about this repair.

Red shouldered hawkThe southern study area also had another roadkill buck on Route 322. This buck was captured on 3/3/16 in Rothrock. This is our fourth deer to meet its demise on Route 322 within the last 3.5 weeks [remember that pulse]. 

On the bright side, I saw a pretty red-shouldered hawk this week and a barred owl last week. Two of my favorite birds of prey! Then again, I think I say that about all birds of prey.

Happy Thanksgiving! 

-April
Field Crew Leader
PGC Deer and Elk Section

 

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Let them call me a tree hugger

I have always been fond of the American beech (Fagus grandifolia). The bark is a striking silver gray making it easy to spot in the woods. Unlike other tree species, beech bark keeps its youthful appearance throughout its life. No deep crevasses or wrinkles will ever be found no matter how old or big it is. It’s like the Paul Newman of trees. 

Have you ever hugged a beech tree? The bark feels like it has been shrink-wrapped to the wood beneath! Taut and smooth. The next time you’re out in the woods, give it a try.  It’s a lot more welcoming than an oak or maple.

Speaking of oak and maple, only white oak and sugar maple live longer – in fact the oldest known beech trees were found in Pennsylvania clocking in at more than 366 years old. 

Beech, like oak, produce hard mast (a fancy word for wildlife food, soft mast is the term for foods like blackberries, black cherry fruit, etc.). Beechnuts are nutritious and tasty (even for humans!).

How do you know when a beech tree is mature enough to produce mast?  Look for bear nests.  Yes, you read that correctly.   Read the smooth bark for graffiti first – claw marks are forever on beech bark.  If you see them, look up.  After Yogi climbs the tree and finds a nice place to perch, he reachs out, breaks off a branch, eats the nuts, then stuffs the broken branch underneath him.  A bear-sized appetite produces a bear-sized “nest” in the beech tree.

In the past couple of weeks, I’ve had different people ask me about all the beech seedlings they’ve seen in the woods. It’s funny how that happens.  Similar questions from unrelated incidents from completely different audiences.  Serendipity. 

“Is this a sign the forest is recovering from past deer browsing?”

“When will these trees be big enough to produce mast?”

Unfortunately, the answers to these questions are NO and NEVER.

A disease is killing our beech trees. It’s actually a fascinating disease complex dating back to 1849 when it was first seen in Europe. By 1890, the disease had made its way to Nova Scotia. It has been spreading across North America ever since.

The beech scale (Cryptococcus fagisuga), a small insect about 1 millimeter (0.04 inches) long, feeds on the bark cells of the tree.  Perhaps sucking the essence of the tree’s vitality and beauty.  To complete the stereotype, there are no male beech scales – only females that reproduce via parthenogenesis.

The beech scales’ quest for eternal youth does not kill the tree, but instead opens the door for another invader.

Through this open door walk two species of fungi, N. coccinea var. faginata and N. galligena. It is they who kill the beech. In an ironic twist, the fungi eventually make the tree inhospitable to the beech scale. The “she’s” are ousted…their fountain of youth evaporated.

But what about all the beech seedlings?

Those “seedlings” are actually root suckers sent up by the dying adult trees as a last gasp. If you look, they are clustered around a larger tree which is, in fact, clinging to life.

If you inspect these larger trees, you will notice the damage to the bark. It’s not smooth and taut anymore.  It is cracked and wrinkled unable to fend off ferocious fungi and other fiendish organisms.

 

These seedlings are doomed, never living long enough to become a mast-producing tree. Which means no more black bear nests.  But bears aren’t the only ones weeping at the death of the beech – squirrels, wild turkey and many other animals all mourn the loss of the beechnut as well.

But what about deer?  Maybe the seedlings could feed the deer?  Wishful thinking.  American beech is not a preferred species of browse for white-tailed deer. 

Beech seedlings are also VERY resilient to deer browsing even if deer do partake in a snack. Why do I mention this?  It means the presence of beech brush provides no indication of the intensity of deer browsing. It may look like the forest is recovering but looks can be deceiving – you have to look at other plant species to assess deer browsing intensity.

Dense stands of beech brush shade out many other species of tree seedlings and herbaceous plants that could provide food for deer and other wildlife.  Triple whammy!

So all is not as it seems. What looks like a regenerating forest is really the consequence of a dying species.

It’s why Aldo Leopold wrote, “One of the penalties of an ecological education is that one lives alone in a world of wounds.”

The next time you see a healthy beech tree, feel it’s bark. Appreciate its simple beauty. They probably won’t be around forever. And if you dare, give it a hug for me.

-Duane Diefenbach

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Deer Crew Diaries – Entry XLIII

 
——————————————————————–
From the Northern Crew:

Dear deer people,

I spent the better part of my week tracking undead deer that sent, what turned out to be, false mortality messages [no technology works perfectly!]. Last Saturday, Sunday, and the following Tuesday, I was hot on the trail of Buck 8809, which was collared in February of 2014.

Looking at his GPS locations online, I could see that his normal home range is in the Susquehannock State Forest. However, with the rut in full swing, he had crossed over onto a large swath of private land owned by a forestry company and leased to several hunting clubs.

This made getting land access slightly more complicated. But after talking to some folks in the area, I was able to track down the right people, who were all very gracious in granting me permission. My search for this potentially dead buck ended anticlimactically when I hiked into his last-known location on Tuesday and found nothing but a deer bed and some tracks. He has since resurrected back to life and returned to the Susquehannock for the time being.

Also this week, I picked up one of my trucks from the shop while dropping off another (a never-ending cycle), compiled a supply list for trapping season, and searched for the MIA fawn with no success (missing since 11/7). I also attended the Soup to Nuts presentation given by Duane and Chris on Sunday at the Lumber Museum – very interesting stuff!

Fun fact: I saw a group of 11 does in the Susquehannock on Monday! And where there are does this time of year, there are bucks 😉

-Hannah
Field Crew Leader
PGC Deer and Elk Section

——————————————————————–
From the Southern Crew:

Hi all,

Levi assisted me with trapping tasks on Tuesday. Since our old 1999 F-150 (Greenie I) was sent to surplus this spring and was replaced by Greenie II (the crew truck), we had to go through the rusty tire chains to find something that’ll work for the winter. We tested the tire chains that I kept in my truck to make sure that they were still usable. I also hosed out the bed of Brock’s (elk bio aide) old truck since it smelled like a dead elk and topped off the fluids.

I monitored and obtained locations for all fawns. I also went through the shed and my supplies to nearly complete a “winter trapping supply needs” list.

I had to cancel my volunteer for Sunday, because I didn’t want her driving to State College in potentially nasty weather. She’s planning on coming out in December though.

Since next week is Thanksgiving, many of us will have a shortened work week! I’ll be headed out-of-state for Thursday but will be back by Sunday before deer rifle season begins.

Sunset from Lake Rd

I’m planning on attending the Beavertown bear check station on Monday, getting Clover traps from State Game Lands 215 on Tuesday with Levi’s help, and obtaining locations on the fawns on Wednesday.

It’s beginning to feel like fall with the cooler temperatures and snow beginning to show up on the radar in our region, just in time for deer rifle season.

-April
Field Crew Leader
PGC Deer and Elk Section

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When do they sleep?

If you have ever spoken to a hunter seeking his quarry, the phase “go nocturnal” often sneaks in.  It refers to deer changing their activity pattern with increased hunting pressure – moving more after dark than during daylight (i.e. legal hunting hours).

During the rifle season we obtain locations every 20 minutes on bucks. What a great opportunity to see if the infamous “go noctural” is true.  And even better, our collared deer are at least 2.5 years old. Some are now at least 5.5 years old.  So they’ve been around the block a time or two when it comes to hunting season.

I took all our data from 2013, 2014, and 2015 and calculated the speed (meters per hour) every 20 minutes that every deer traveled during the rifle season.

And because behavior during the first three days (when the most hunting pressure occurs) might be different from the rest of the hunting season, I summarized the data for Monday-Wednesday after the opener and then for the remaining nine days (Thursday through Saturday).

Take a look! Legal hunting hours are about 7am to 5pm (highlighted in yellow). The least movement occurs between 9am and 4pm, with peak movement occurring 6am-8am and 5pm-7pm.

The peak speed is about 180 m/hr just before sunrise and just after sunset. From 10pm to 6am it’s about 60-80 m/hr. During the day movement is at its lowest when deer move about 40 m/hr.

Deer-Forest Study

Now let’s take a look at what they do later in the rifle season. Just about the same thing, but peak speeds are reduced to 100-140 m/hr. Notice that nighttime speeds dropped to about 60 m/hr, and daytime speeds dropped to about 30 m/hr. Clearly deer are responding to hunting pressure and reducing their movements.

Deer-Forest Study

Of course, if you’re a devoted reader of this blog that’s not surprising. We have shared with you that daytime home ranges are only about 100 acres during the rifle season.

So is this proof that bucks go nocturnal? I’m not so sure.

Deer are a crepuscular animals by nature, meaning they are most active around sunrise and sunset. Perhaps the data from our deer suggest they shifted their movements more to the darker side of sunrise and sunset.

Unfortunately, we don’t collect locations on bucks every 20 minutes outside the rifle season. However, we do collect these data for does with fawns. So let’s look at their data for October and see when they are active.

Deer-Forest Study

First, keep in mind that daylength is slightly longer (7am-7pm).   Movement peaks about 8am in the morning and just after sunset. If you ask me, it doesn’t look that much different from bucks in rifle season except the peak is lower at sunrise and slightly more active in the few hours after sunrise. However, given the amount of early morning hunting activity in rifle season, those differences are not surprising.

So I’m afraid I don’t buy into the theory that deer “go nocturnal” during the rifle season. They’re clearly crepuscular and reducing their movements overall.  But they’re certainly not becoming vampires!

The bummer is that bucks are not moving much during the middle of the day. But take heart, there are always exceptions to the rule! I plotted the maximum speeds of deer and any time, day or night, you can find deer moving over one mile in an hour!

Deer-Forest Study

Remember, averages are just that – an average – and do not reflect the variability in behavior.

Also, in my hunting experience in Pennsylvania (and other places), there seem to be a lot fewer hunters in the woods by the time lunch hour rolls around. Pack a lunch and see what other hunters are missing.

Watch this buck during the 2013 rifle season (we start the movie on Sunday, December 1, 2013). If any deer might be called nocturnal, it could be him because he makes long-distance movements at night.

But pay attention to his moves in the early afternoon. Even on opening day by 2pm, he has started to make substantial movements. And he does this more than once.

The other thing I love about this buck…he hides on public land! Where does he go at night? Down in the valley on private land but his hiding spot during the day is on public land.

-Duane Diefenbach

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Old Men

It is no secret that deer can live into their teens.  I’ve written about several old “ladies” in the past.  What I haven’t written about is old men.  Bucks with their flashy head gear are highly sought after during the hunting seasons.  Needless to say, not many of our tagged bucks make it to a ripe old age.

That doesn’t mean we haven’t tagged some old bucks.  But if they are adults at the time of capture, there is no way to determine their exact age.  

Well, I can finally write a post about old “men.”  A couple of weeks ago, we got a phone call from a hunter reporting a tagged deer.  Nothing out of the ordinary about that this time of year.  Reward tagged deer are reported to us throughout the hunting seasons.  

When we looked up the tag, we discovered that this buck was tagged in 2010 as a yearling which means he was 8.5 years old!  The hunter was nice enough to forward some photos and he was rather impressive.  

Buck11144-front    Buck11144-side

This buck was harvested during the archery season.  So, rifle, muzzleloader, and late archery hunters are out of luck this year.  But he was available for harvest as a 7.5-year-old, 6.5-year-old, 5.5-year-old, 4.5-year-old, 3.5-year-old, and 2.5-year-old for every deer season!  That means this buck outsmarted hunters for 6 years.  If he was a legal buck as a yearling, that would make it 7!  And let’s not forget, he was an antlerless deer for one year too.

He wasn’t as old as our Katniss Everdeen of 2G, but 8.5 years old is pretty old for a buck.  To give you a little perspective, less than 1% of bucks harvested are older than 7.5 years old.  

The hunter who harvested this buck was pretty awesome too.  He declined the $100 reward and asked that it be used on future research.  I guess Buck 11144 was reward enough.

-Jeannine Fleegle
Biologist
PGC Deer and Elk Section

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Is anybody home?

Anybody who’s ever used a trail camera knows how much fun they can be.  It’s amazing what goes on in the woods when you’re NOT there.  But trail cams aren’t just for scouting.

Camera traps are one of the coolest ways for researchers to study wildlife. You not only get really interesting data—pictures and videos of animals doing their thing!—they are relatively cheap, you don’t have to bother animals (remember those VITs!), and they can tell you a number of things about wildlife like when they’re active, where they are, and what habitat they use.

Mapping where a species can be found is particularly useful.  The fancy term for it is Occupancy Modeling. Researchers estimate the probability that a site is occupied, which tells you what proportion of your study areas is occupied by the species of interest. 

Let’s say we are all about coyotes.

Occupancy probability takes into account that while a coyote is present in the area of a camera station, you might not see it (because it’s not feeling photogenic). 

For example, we set out 10 camera stations (each camera station is represented by a circle in the figure below). Either we detect a coyote or not at each station.

If we detect coyotes at 3 of 10 stations (naive occupancy = 0.3) we know that at least 30% of the study area has coyotes… but it might be more (we call the proportion of stations where coyotes were detected, 3 of 10 or 0.3, “naive occupancy” because it does not account for detection probability).

What we would really like to know is the proportion of the study area where coyotes occur. That means we need to account for the probability of detecting an animal to estimate what proportion of stations coyotes are present even though we failed to detect them!

For example, true occupancy is the proportion of stations where coyotes were present whether detected or not (the orange and blue stations in the figure below).

Below are some examples of naive occupancy from a small part of our data from the Bald Eagle State Forest. At ten camera stations, we tracked whether we saw deer, black bear, gray fox, coyote, and bobcat.

 

 

 

We can easily see that deer and black bears are present at more camera stations than bobcats or gray foxes. However we haven’t taken into account the camera stations where a species could have been, but just wasn’t detected.

In order to get a true picture of occupancy, we need to factor in detection probability.  Detection probability is estimated by looking at the capture histories over time and space. 

Each camera station has its own ‘capture history’, which is simply a record of each day when we detected a bear (=1) or not (=0). For example, our capture histories for bears at 10 camera stations might look like this:

Camera Capture history
1
2
3
4
5
6
7
8
9
10
1000001010
0000010001
0011001000
1010100000
1111000011
0000000000
1000000110
0010110000
1100000101
0000000000

So let’s look at bear occupancy, this time with detection taken into account:

beartrueoccu

Our naïve occupancy estimate (that does not include detection) is 0.8 which is close to our true occupancy estimate (with detection) of 0.9. This means we have a high bear detection probability. If there was a bear at a camera station, chances are it actually showed up on the camera. But still, from our analysis we would not expect to detect a bear at 1 in 10 stations, or 10% of the area. Without doing our analysis, we would have underestimated occupancy.

In the future, we will be running occupancy analyses for multiple carnivore species and deer at over 100 camera stations across three study sites. With these analyses, we’ll look at habitat use and whether the presence of one carnivore species—say coyote—influences the presence of another carnivore – like fox.

And you thought trail cams were just a fun toy!

-Asia Murphy
Ph.D. graduate student
Ecology Program
PA Cooperative Fish and Wildlife Research Unit

 

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Soup to Nuts: A Deer-Forest Study Thanksgiving

Where: Pennsylvania Lumber Museum, 5660 US-6, Galeton, PA 16922

Date: Sunday, November 20, 2016

Time: 1:00 PM

Admission: Free and open to the public

Dr. Chris Rosenberry, Supervisor of the Deer and Elk Section of the Pennsylvania Game Commission, and I will be giving a presentation about The Deer-Forest Study. We will provide an overview of the project as well as some preliminary findings, including fawn survival and buck movements. You might even get some insider information on the patterns of those older bucks!  It might come in handy in a week or two.

If you need directions, or more information about the Pennsylvania Lumber Museum, you can find it all at http://lumbermuseum.org/

-Duane Diefenbach