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Meet the professionals: Tori , Sean, and Matt

Black bears:
Diet
Habitat
Reproduction
Research
Human Interactions
Questions

Name: Tori Seher

Title: Wildlife Technician
Organization/Department: Resources Management/Wildlife Unit
Field of study/research: Management of black bears and people

How long have you been doing this?
5 years

How did you get interested/involved in your field of study? What was your degree in and where did you study?
Ive always had an interest in animals. I developed an interest in environmental issues, and then became involved with environmental groups.
Went to Arizona State University and got a degree in Wildlife Conservation Biology

Do you like your job? What are some positive and negative aspects of what you do?
Yes, I love my job
Positive: Help protect Yosemite Wildlife; work in this beautiful place, Yosemite. Get to see neat animals
Negative: Frustrating when people can’t do easy tasks like proper food storage

For those out there who may have an interest in the study of animals or something of that sort; is there anything you can tell them about what you do and how to get there? What colleges to go to? What to study? Steps to take to put you in the right direction?
Look for a college that offers a wildlife degree, be active, volunteer, work experience is important, apply for Student Conservation Association (SCA) internships

How many bears have you seen? What’s it like to see a bear?
A whole lot…. If you work at night you see them all the time
I’ve seen about 100 individuals.
It’s exciting; your adrenaline goes up, it’s sad when you see them in a campground though. It’s frustrating to have to haze them and scare them off.

Any especially memorable experiences?
My memorable moment would have to be placing three cubs in rehab for nine months in 2000-2001 and building a den in the winter season in the backcountry and returning them into the wild. It was a success, they’ve been staying out of trouble.

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Name: Sean Matthews
Title: Research Wildlife Biologist
Organization/Department: Wildlife Conservation Society
Field of study/research: human-wildlife conflict
How long have you been doing this?
2 years in Yosemite, 4 years of bear study prior to Yosemite

How did you get interested/involved in your field of study?
“Just fell into it” Had a general interest in the outdoors and went backpacking as a kid.

What was your degree in and where did you study?
Bachelor’s degree in Wildlife management and a Master’s in Natural Resources, Humboldt State University.

Do you like your job? What are some positive and negative aspects of what you do?
Yes. It is a (good) challenge to work on interesting questions with real life implications, coming up with answers that will make a difference. I also like working outdoors with great people.

Some of the negative aspects include working with “soft money” – trying to find grant money to fund my projects. It is challenging to coordinate efforts with the National Park Service and other organizations.

For those out there who may have an interest in the study of animals or something of that sort; is there anything you can tell them about what you do and how to get there? What colleges to go to? What to study? Steps to take to put you in the right direction?
Be active: find a job in the field, especially in the summers. Volunteer only if you have to. Find a university with professors that are researching things that you are interested in.

How many bears have you seen? What’s it like to see a bear?
In Yosemite, 30-40 individuals. It can be frustrating to see a bear in campgrounds [because it is not a natural area they’d be in without humans].

Any especially memorable experiences?
We trapped a sow (female bear) in a bear trap that had two cubs outside of the trap. Another researcher, Kate, and I were working on the sow, waiting for it to fall asleep after we had tranquilized it. After getting no response after I tapped it, I went in the trap face first. The bear apparently wasn’t asleep quite yet though, and turned its head towards me, putting its paw up directly in front of my face! Kate pulled me back by the seat of my pants and saved me from getting swatted at close range.

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Name: Matt Grove
Title: Wildlife Technician
Organization/Department: Resources Management/Wildlife Unit
Field of study/research: Management of black bears and people

How long have you been doing this?
I’ve been working since last June on bears in Yosemite, but have worked on other wildlife research seasonally (in the summers) since 1999. I’ve worked on amphibians, desesrt tortoise, and trout in many places including Mount Ranier National Park, the Mohave Desert, and Great Basin National Park.

What was your degree in and where did you study?
I went to Southern Illinois University, and have my bachelors degree in Zoology.

Do you like your job? What are some positive and negative aspects of what you do?
I like studying wildlife, and this job is frustrating because more of the work is actually dealing with people and improper food storage. When we track bears, we only check for presence and activity, which isn’t an exact science. I prefer to work on projects that have stricter scientific protocols.

I also get fed up with looking for a new job every summer. I also son’t like having to move around a lot although, the jobs I’ve had have let me see many beautiful places.

For those out there who may have an interest in the study of animals or something of that sort; is there anything you can tell them about what you do and how to get there? What colleges to go to? What to study? Steps to take to put you in the right direction?
Volunteer! Get involved as soon as possible, in high school and in college. Use your summers wisely, and try to get jobs that are in your field of study. Lots of places rely on volunteers because budgets are low.
I may want to go back to school for my masters degree, but I took some time off after my undergraduate education to work. In the past few years I have worked with many kinds of wildlife and realized that I wasn’t really into bears or large mammals, but that I like studying aquatic invertebrates. This was important that I realized that before I went on for more school., So, if you are not sure exactly what you want to study, just start getting experience in anything related.

How many bears have you seen? What’s it like to see a bear?
I have seen most of the 18 bears that we have radio collared in Yosemite Valley. In my position it is usually depressing to see a bear because we deal with human bear interactions, meaning that most of the time the bears are not acting as they would in the wild.

In the summer how many bears/night do you encounter?
It can be anywhere from 0-6 bears a night, sometimes you may even see the same bear twice in one night

Any especially memorable experiences?
I’ve been screamed at by some visitors and others are overly thankful, saying that I “saved” them from a bear attack (he laughs). Some of my favorite bear sightings were in natural settings: I saw a sow in a meadow and once watched one take down a deer, drag it to the river and drown it. That was pretty spectacular.

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DIET (Sean's answers are marked with an S:, Tori's with a T:, and Matt's with a M:)
What do bears eat?
S: Everything! Berries, nuts, acorns, grubs, bees, ants, termites, wasps, apples, human food, small rodents/ground squirrels, and sometimes-unhealthy deer.

How do bears hunt (sight/sound/scent?)
T: They use all their senses, mostly smell, but they see just as well as humans

S: Regularly in the wild, bears are diurnal or a crepuscular hunter, that is they naturally hunt during the day or around dawn and dusk. Wild bears use both sight and smell when foraging for food.

Bears in more developed areas with a human presence like Yosemite Valley are more nocturnal hunters (they hunt at night). Because it is dark outside at night, they mainly use the sense of smell to locate food.

To identify and characterize the diets of individual lions do you need to examine the feces when it’s fresh? Can it have been there for days or weeks and still be good?
S: It depends on your research objective – if you want to find what they eat, it can be any age, if you want to find out what they eat in a particular season you need to determine its age by measuring the moisture in it.

We determine scat age by testing with fresh scat that bears have left in bear traps (where we know the age of the scat). We put the scat in different levels of sunlight – shade, partial shade and full sun. This way when we find scat in the forest or in a meadow, we have an index to help us judge how old the scat is.

Are there other methods you use when determining the diet?
S: We examine gut content on bears that are found because of road kill, hunted bears, or in studies that have authorization to kill bears. This method is more accurate because the food is not digested as thoroughly – you can detect the percentages of the types of food they eat better than scat analysis. Obviously this is a more invasive procedure, and is not used as readily.

What is the current NPS policy/ management plan for controlling bears in Yosemite? Where are they controlled? Who makes the decision to “put a bear down”? How many incidents does it take before a bear is put down?
T: That’s a complicated question. You should refer to the human bear management plan
This includes managing people, eliminating human food for bears, enforce regulations for people.
This is being controlled in the front country where there’s visitation.
The decision is made to put down a bear when it’s become aggressive, this could take one or more times depending on the incident. To put down a bear we recommend this to the Yosemite Bear Council, where it’s voted on, then it goes to the Chief of Resources and then to the Super Intendent who has to approve it.

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HABITAT
How much territory does the animal need? Do you think we are moving in on bear territory?
S: Depends on food availability and habitat availability. There may be a few per 100 square kilometers, but with a greater food density in an area, the habitat size can be much smaller.

What kind of environment/habitat does the animal depend on? Does it change throughout the year?
S: It is food dependent and varies through the year. In the spring they feed on grasses and forbes (flowering plants) in meadows and prairies. In the summer, berries are a major part of their diet, and in the fall they are in the forests feeding on black oak acorns. In the winter bears choose when, where and if they should den which mostly depends on the weather and food availability. In the spring, males are looking to mate, and they may forgo feeding priorities to find a mate.

I was told that during the winter season bears don’t hibernate, because in order for them to hibernate they have to become torpid, which would include them having to fall into a deep sleep and not wake up, but bears actually get up and walk around, is this true?
S: True hibernators are categorized by a decreased heart rate, lowered body temperature and decreased brain activity when in their hibernating phase. Bears go into “torpor” which is similar to hibernation but ears only experience a subtle decrease in the above functions. They may or may not eat or defecate, depending on the weather.

I have actually encountered a mom and cubs that have changed dens during the winter. There is also a bear in Yosemite Valley this winter (2002-03) that hadn’t established a den site.

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REPRODUCTION
When do bears reproduce? What’s mating season like? Do they have a mating call? How long does mating season last?
S: Bears mate in spring and early summer. Males compete for females indirectly by competing for habitat. Both males and females may mate with multiple partners.

There is a delayed implantation of the egg once bears mate; the egg is fertilized but doesn’t implant on the uterine wall until fall. Cubs are born late January/early February.

The number of cubs depends on the availability of food. The sow can abort pregnancy in the fall if there is a low abundance of food. The average sow will have 1-3 cubs per reproductive cycle.

T: I saw two bears fight once and it wasn’t as dramatic as I thought. They stood their ground and kept staring at each other. Then started to slap each other a little and wrestled. Just minor stuff.
We saw two tagged bears that mated with each other for three weeks, we never saw them apart.

Are there any rituals that the bears do?
S: Not that we know of.

Who does the post-natal care? For how long?
S: The sows (the mothers) take care of the cubs for about one year after they are born. After exiting the den after being born, the cubs are weened off their mother’s mild and ready to search for food. The mothers teach the cubs about foraging and avoiding predators for about one year.
After the next winter’s denning season, the cubs go out on their own, and the mother can reproduce again. Sometimes cubs are orphaned and adopted by another mother, in which case the biological mother becomes fertile for another season of mating.

What is the life expectance of a cub after birth? Are they in danger of being hunted by other predators?
S: Inexperienced and first time mother sows have more of a challenge finding food and protecting their cubs than sows that have had cubs before. Cubs are definitely threatened after birth – adult male bears will kill cubs to bring the sows back into esterous (fertile for reproduction). Other threats include predation by mountain lions and humans in cars. Once there was a sow that got hit by a car in Yosemtie. Her cubs stayed near her body and eventually got hit as well.

How often do you come across orphaned cubs?
T: There have been two occasions. There was a sow that was hit by a car and killed. We’re not sure if when the sow died, the cubs ate her or just the magets that were feeding off of her, but they survived and we found the cubs scat around the sows body.

S: I never have. Usually you won’t see one in rehabilitation that hasn’t been weened yet – usually they are always found after denning.

What happens to orphaned cubs? If they have to be nursed and taken care of by humans what are its chances of returning to the wild? What happens to the bear if it can’t be released back into the wild?
T: There was a mother bear that had to be euthanized, her cubs were five months old and ate solid food. All three cubs were successfully returned into the wild.
Most bears become wild on there own, they don’t want anything to do with people. Even in the zoo, once the bears reach 100 lbs. the zoo keepers are in danger.

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RESEARCH
Is there a limit (a boundary) to the area you’re allowed to research or work in? If so, will you get in trouble for going out of that area?
S: The area of my study’s focus of human-wildlife conflict is in Yosemite Valley.
T: Yosemite only. We don’t relocate outside of the park

What is radio telemetry and how does it work?
M: We use radio telemetry to track bears in Yosemite Valley. We use 6 points in the Valley where we listen for bear collar sounds. We do not actually track down the bear by triangulation, we simply gather data about whether the bear is active or inactive, the general direction of the signal and the strength of the signal.

The two parts of the equipment are the radio collar, which we put on bears, and a receiver which has a large antennae attached. Each bear’s collar gives off a different frequency, so we adjust the receiver one dial at a time to listen for each bear. We hold the receiver near our ears and turn the antennae 360 degrees to pick up any signal of the bear.

Why does the speed and strength of the beep tell you?
M: The stronger the beep, the closer the bear is. If the beep is slow, that means the bear has been inactive for more than 24 hour period. If the beeps are faster, it means that the bear is active.

While tracking bears with Matt, Houston and Jocelyn heard 3 active and 2 inactive bears on the receiver!

Do you believe that it is a good idea to capture and install radio transmitters on bears? How does this affect its way of living? Does it hurt the bear? How do you install the transmitters?
T: For management it helps us know what active bears we have in the park and if the bears are in the area. But there’s always a risk in handling animals.

S: Transmitters are always an issue and whether you should use them depends on the research question you are asking. A researcher should consider if they really have to capture and risk hurting the animal.

S: Some radio transmitters have killed animals. The most common way is that as the animal grows, the collar may rub the skin raw and cause infection. Some animals have got a branch caught up in the collar and have hung to death. Sometimes, especially in many ungulates, the foot/hoof of the animal gets caught between the collar and the neck, a condition called tripoding, which usually results in the death of the animal.

You shoot rubber bullets at bears to scare them off, how does this affect the bears? Does it hurt them?
T: It’s not intended to hurt them. It more for domination, to show them who’s bos, to make them afraid of humans, which is the point so that they won’t feel comfortable around us. It probably doesn’t feel too good, but we shoot them from a distance so that it doesn’t hurt so much. This is all part of the hazing we do along with yelling.

Are there other ways that you track and research the animals?
S: Yes. Satelite telemetry is used; the animal still wears a collar, but the researcher uses Global Positioning System (GPS) technology to track the animal with the help of satellites. The GPS unit can be set to record the exact location of the animal at certain times or dates and can also send that information to the researcher in the field. Many times ground observations are used where the researcher is either walking or driving. Tracks can be followed as well to locate the animal. Especially for animals that travel great distances like ungulates (deer, elk etc.), researchers track animals aerially from planes. Dogs can also be used to help capture bears.

Other research methods include scat surveys, especially year to year comparisons. Remote sensors/cameras can take photos of the animals without much human interaction. Barbed wire is put out as a “hair snare.” Hairs can be sent to labs where DNA analysis can determine what animal and sex the animal is, and can help determine how numerous bears in a given area are related.

How can you determine a bear’s age?
S: Bear teeth grow rings just like tree do, with each ring equaling one year. We take a tooth sample from a pre-molar tooth and send it to a lab. We do not take teeth out of most bear that we capture though, we have a dichotomous key to help us determine the age of the bear. Obviously if we know when the cubs are born we know the age of the bear.
T: Tooth samples. We estimate by the wear

What can a paw print tell you? What does its size say about that specific animal?
T: It can tell you the animal’s size, but this isn’t always true. It all depends on what the paw print is in. If it’s in snow and the snow has been melting then the print might look bigger then it actually is.

With all of the programs being put together to save the bears, are any of them working? Are the bear problems getting better or worse?
T: It’s gotten better. Some effective programs are the interpretative ones where the rangers talk to the visitors. The hazing program also, we re-educate the bears by shooting rubber bullets, etc at them and shouting to scare them away from the people.

Before transporting a bear to another area of the park you weigh them, why do you do this? What does this tell you? How does it help?
T: It helps us assess the bears health condition, see if they eat too much or not enough, etc.

S: In my study we look at weight to see how “naturally” the bear is finding its food. A wild bear typically weighs less than a bear that feeds on human food in campgrounds. We are comparing the weight of bears in Yosemite Valley over a time period to see if bears are eating less human food.

Do you ever capture bears just to weigh them?
T: No, we mark them with ear tags and radio collars. We don’t really relocate bears anymore; we’ve found that they just keep coming back. We release them on site, and haze them.

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HUMAN INTERACTIONS
Are humans contributing to apparent changes in bear behavior? How so?
S: Definitely. Bears that roam campgrounds for human food have changed from hunting during the day (diurnal) or dawn and dusk (crepuscular) to being most active at night (nocturnal). In addition to this lifestyle change, the bears food base changes, they prefer human food and will seek it out. Their home range may shift as well, getting smaller if food abundance goes up.

How often do bears break into vehicles? Are people ever injured in the process?
T: Not often, but in the summer time usually several times a week. 75% of the time they obtain food because it has been improperly stored.

I read that the park closed down Rancheria Falls Campground in order to hopefully save some bears from being destroyed later on in 2001, does this happen a lot? Are there any more problems at Rancheria Falls Campground?
T: No, this is the first that I know of. It worked well. This is a great area for bears, lots of berries and nuts and fruit for them. We wanted to let the sow be able to teach her cubs natural hunting methods, not interacting with humans and their food.

Over the years bears have been spotted in other areas outside of the parks and forests, they’re being found in areas near Monterey and Santa Cruz counties as well as some others, do you think that the bears territories will continue to expand and cover most, if not all of California’s land before the century is gone? If this does come into place how will it affect the living of people in California?
T: Bears do well in small mountain towns, there’s food storage and trash cans and dumps. In a situation with drought bears look for other food sources also. I think people need to be educated in order for us to co-exist. Although they probably wouldn’t survive in city areas like Los Angeles, but people keep moving into these suburban areas where bears are located.

Do people still hang their food from trees? Why or why not? Are people required to use bear canisters when they’re out camping?
T: Yes, unfortunately. But this doesn’t work in the Sierras. We have bears that climb the trees and walk out on branches to jump onto the bags of food.
Bear canisters are required in only three locations: anywhere over 9,600 ft (because there are few trees to hang food from)., at all High Sierra camps, and at Rancheria Falls Campground.

After a bear has become accustom to living off of humans and you capture and relocate them, what are their chances of survival in the wild?
T: They can survive, their biggest concern is getting beat up by other bears and trying to find a local home range

How often do bears return to the Valley after being relocated?
T: 99.9% of the time they return. The only bears that don’t return are the younger ones because they usually can’t remember their way back.

Do you have to relocate bears a lot?
T: No, we try not to

How do you destroy bears? What do you do with the bodies once they’re killed?
T: By lethal injection, we only use safe drugs. The carcass is either donated to the Native Americans, the interpretive division, or we find a place for it so the animals can eat it where no people will find it.

How many bear have been put down in the last decade?
T: 1 in 2002
3 in 2001
5 in 2000

Have you ever had to “put down” a bear? How hard is it for you to have to “put down” a bear?
T: Yes, I’ve had to put down four. It is extremely difficult. I understand why, but I didn’t get into this business to kill animals. It’s sad because most of the time it’s a result of people not storing food properly.

S: I’ve had to do it 3 times. Ditto what Tori said, it is very hard, but you also understand.

Do you think everybody who comes to the park is aware of what they should do if they encounter a bear? If not, do you plan on educating people on this and how would you come about doing that?
S: A lot of the people here are repeat visitors and they most likely know what to do. The park is very aggressive in providing bear information and in providing bear-proof food storage options. There are signs, bear food lockers everywhere, and even park rangers that go around the campgrounds talking to people about bears.

I was told if you came across a bear that you should never cower down, always make yourself look bigger and made a lot of noise, possibly throw rocks or something, is this true? Does this work?
T: Yes with black bear this works. They don’t like people and usually wont attack.
However this doesn’t work with grizzly bears. They are fearless and like to fight. The best thing to do with them is to play dead.

Are there ever attacks on people from bears like there have been from mountain lions?
T: Not in Yosemite. When bears break into cars, etc. some people try to take food their from the bears and end up getting slapped by them, which tends to cause injuries. The only attack that ended in a death from wildlife was a young boy who was killed by a deer when his parents tried to take a picture of him next to it.

If I were to have my dog with me, would I be more likely to encounter a bear?
T: Probably not, they’d smell them when they came close.

Have you come across any interesting sights involving bears interactions with humans?
T: A lot of people don’t realize this but bears are very quiet animals. They walk through campgrounds and come so close to people and the people don’t even know. It’s funny to watch.

Is the hunting of bears permitted in the park?
T: NO

Are bears being hunted for population control?
T: Not for population control, it’s mostly for sport. But they’re given a quota based on the size of the bear population. The Department of Fish and Game says that we have anywhere from 25,000 to 30,000 bears in CA, the quota is 1,700 bears.

Does the park have a problem with poachers?
T: Not really but we keep an eye out for them.

Do you believe that we should ban the hunting of bears like we have for mountain lions?
T: Not the ban of hunting, but I think we should ban the way they hunt, the practice. They’re working on the banning of using dogs to hunt.

S: Bears might be more of an issue than mountain lions because bears would have more interactions with humans if hunting was banned

QUESTIONS?
If you have any questions about black bears that wasn't answered here, email Jocelyn and she'll pass the question on to Tori or Sean.

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