Which Enrichment Device Elicits More Interest

From Maned Wolves In Captivity?

______

A Behavior Paper

Presented to the

Junior Science, Engineering, and Humanities Symposium

University of Missouri- St. Louis

______

by

Olivia Monroe

Senior

Rockwood Summit High School 1780 Hawkins Road Fenton, MO. 63026

April 30, 2007- June 19, 2007

Cheryl Apperson Research Teacher 1780 Hawkins Road, Fenton, MO. 63026

1 Abstract:

Enrichment is a process of creating a challenging environment to address an

animal’s social, psychological, and physical needs. Animal enrichment programs have

changed the way that zoos design, construct, and manage their exhibits. This study employs three enrichment devices and includes three experiments to evaluate which device elicited the most interest from captive maned wolves. The hypotheses were that in each of the three experiments, the introduction of the initial device would elicit some response, but the modified device would spark increased interest.

The first experiment employed a plain, cardboard box and a box with cut-out

shapes with color panels behind them as enrichment devices. The wolves were interested

in the device on the first day, but interest waned quickly. The change in boxes (plain to

colored shapes) did not have any affect on the interest level of the wolves. The second

experiment employed a Boomer ball without and with food as enrichment devices. As

expected, the wolves showed more interest in the ball with food. However, the wolves

never learned to get food out of the ball (did not roll it far enough). The last experiment

provided a plain, cardboard box without, and with, food as enrichment devices. Since the wolves had already been presented a plain box, they were not extremely interested with its recurrence. Some interest was shown in the box with food. Throughout the course of this study, the wolves were not as interested in the devices as anticipated. Although the devices themselves did not elicit a great deal of response, it was noteworthy that the wolves’ general level of activity increased, sometimes a great deal, when the enrichment devices were present in their compound. This was encouraging, since enrichment seeks

to increase the activity level of the animals, and these devices seemed to do so indirectly.

2 Table of Contents:

Page Numbers

1. Abstract 2

2. Introduction 4

3. Methods and Materials 8

4. Review of Enrichment in Maned Wolves 10

5. Procedures 12

6. Results and Discussion 16

7. Conclusion 27

8. Acknowledgements 29

9. Tables and Graphs 30

10. Bibliography 39

3 INTRODUCTION

Remember seeing the animals in the zoo for the first time? Were the animals

moving about their enclosure, pacing, or laying down? Is this how they really behave in

the wild? At one time zoos were simply a warehouse of different species the public could

visit. Captive breeding facilities have really evolved over time. Now facilities do a great

deal more than housing and caring for threatened and endangered species. In basic

research, they play a major role to attain a better understanding of the needs of the

species that they maintain [12]. Over the past twenty years, zookeepers have been

making a conscious effort to increase the animals’ quality of life [17]. One of the main

goals for captive breeding programs is to maintain a variety of healthy species so

facilities can release animals into the wild. Having said this, the preservation of natural

behaviors needs to be one of the main focuses of management of the animals [12], and

that’s where a program called enrichment comes into the picture.

Enrichment is a process of creating a challenging environment to address an

animal’s social, psychological, and physical needs [1]. Animal enrichment programs

have changed the way that zoos design, construct, and manage their exhibits. Zoos no

longer manage animals simply as holdings to benefit the visiting public [7]. However,

even though animals sometimes may not be viewed “close-up,” enrichment is anticipated

to increase exploratory behavior, thus enhancing visitor education because animals are more active and display more of their natural behaviors [11]. Enrichment aims to enhance animal activity, provide mental stimulation, and even improve the success of captive breeding of endangered species [1]. It is often a process that provides an opportunity for the animals to make decisions for themselves [6]. Much research occurs

4 that focuses on assessing the effectiveness of specific enrichment approaches. These

investigations typically involve comparing an animal’s behavior before and after a new

stimulus is introduced into its environment [4]. Although this is somewhat subjective, it

is an effective method to measure whether the enrichment changed the behavior of the

animals (i.e., time spent with object or activity). Also important, is to see if the enrichment makes a difference in the breeding success as well. According to the Maned

Wolf Species Survival Plan Husbandry Manual, enrichment cannot be overemphasized and must become as routine as feeding and cleaning [5].

There are several goals of enrichment, but one of the main goals is to encourage

natural behaviors and discourage abnormal behaviors, particularly pacing, exhibited by

the animal in the exhibit or holding area. This is done by evaluating the animal’s natural

history, individual history, and exhibit considerations [2]. Another goal is to help keep

animals mentally and physically fit [6]. In the wild, animals must make decisions about

their activities and movements and are constantly challenged both physically and

mentally by an ever-changing environment. In captivity, animals do not have much

control, if any, over their daily lives. This can be very stressful for the animals, and they

have to learn to adapt. One of the main stressors for captive animals is that they cannot escape and may not be able to avoid undesirable situations. Confined animals have

injured themselves or failed to reproduce because of the conditions of their poorly

designed facility (inability to escape unwanted conditions). The presence of humans can

induce many stressors for animals such as olfactory and auditory cues as well [12].

Therefore, another goal of enrichment is to provide animals with some control over their

environment. To be in control of one’s surroundings means that the animal has the

5 ability to respond effectively to change. This is done by linking the performance of

behaviors with functional consequences. One option for providing animals with both

control and mental stimulation is through the use of species-appropriate mental tasks [3].

In captivity, animals have a great deal of time to just lie around. They don’t have to

forage for food, because the food is provided for them. In the wild, this activity would be

very time consuming. They have no chance to perform the natural behavior of foraging,

and therefore, “boredom” is another thing they cannot control in their environment [12].

The first formal experimental studies of enrichment in zoos began in the late

1970’s when San Francisco State University psychologist Hal Markowitz created a

mechanical food dispenser for the white-handed gibbon (Hylobates lar). The device

reinforced the primate to use creative problem-solving abilities [16]. Enrichment has definitely grown since then. Zoos and other captive breeding facilities have made a great deal of progress in providing animals with enrichment.

Enrichment can be visual, olfactory, auditory, tactile, and taste stimuli. It can be incorporated into the captive environment itself, but also in daily behaviors like foraging

[15]. Many devices used for enrichment have been developed. Some of these devices include: Kong toys, Boomer balls, furniture for the enclosures, feeding devices, rubber hoses, plastic containers, old car/truck tires, scented objects, etc. Novel objects, or toys, have been a very common tool used in enrichment techniques to provide the animal opportunities for interaction and exploration [12]. However, enrichment is only enriching for an individual animal if the animal finds it so [8]. Most enrichment items are highly attractive on the first day that they are presented, but animals’ reactions typically decrease to zero within a matter of a few days [10]. Other items may keep an

6 animal’s interest for a longer period of time, and some items may never elicit interest from the animals whatsoever. Hall et al. performed a study of object-play with cats in

2002, and presented data that showed that domestic cats displayed a decrease in play

when the same object was presented repeatedly [9]. In contrast, they displayed an

increase in play when a certain object characteristic, such as the color of the object,

changed. The effect of familiarization with the sensory characteristics of an object causes

acclimatization to occur. Therefore, there appears to be a relationship between an

object’s stimulus and the animals’ interest in a particular object [9]. The most effective

enrichment items are those which contain species-specific stimuli and, therefore, cause

the animals to use natural behaviors, so those used with mammals help stimulate play or

hunting/foraging behaviors [10, 13]. Enrichment objects offer an easy way to slightly

alter an exhibit in order to create a more interactive environment.

Novel objects can also affect the way a group of animals behave toward each

other. If there is only one object, the animals might display more aggression than they

normally would. This might be desirable if aggression is natural. Often though, it would

make sense to present a number of objects, especially if there are many individuals in one

compound, so major aggression does not occur. While presenting a limited number of

objects may produce more aggression through competition, a wide variety might allow all

individuals in the enclosure, including subordinate animals, to have access to the enrichment. A study done with primates showed that the presentation of an abundance of

novel objects was very successful. They secured most of the objects, and every

individual was able to use the devices [12].

7 METHODS AND MATERIALS

STUDY SITE

This study took place at the Wild Canid Survival and Research Center. The

Center was founded in 1971 by Dr. Marlin Perkins, his wife Carol, and a group of individuals concerned about the plight of canids. It is located at Washington University’s

Tyson Research Center in Eureka, Missouri and consists of sixty-three acres of woodlands. The canids at the Center include: the maned wolf (Chrysocyon brachyurus),

red wolf (Canis rufus), Mexican gray wolf (Canis lupus baileyi), swift fox (Vulpes velox),

and African wild dog (Lycaon pictus). The primary goal of this Center is the preservation

and reintroduction of these endangered species. The Center strives to educate the public

about these endangered animals as well. The studied enclosure was 16,520 square feet in

size and contained two maned wolves. There are additional maned wolves at the center.

GENERAL BIOLOGY OF STUDY SPECIES

The maned wolf (Chrysocyon brachyurus) is the largest of the South American

canids. This species covers a vast range in South America. Its current geographic range

extends through the grasslands and scrub forest of northeastern Brazil, west to the

Pampas del Heath in Peru, and south through central and southern Brazil, Paraguay, and northern Argentina, an area covering approximately five million km2. The maned wolf is

classified as vulnerable by the International Union for the Conservation of Nature, and

endangered by governmental agencies in Brazil and the Argentina Wildlife Board. The

maned wolf population in Brazil is approximately 1,500-2,000 individuals occupying

650,000 km2, and about 2,200 occupying an area of 200,000 km2 in Argentina. Habitat

8 modification for agricultural use seems to be the biggest threat to wild populations of the

maned wolf [18].

The maned wolf is not a true wolf. It has an evolutionary history that dates back

six million years ago to a time when many large canids became extinct in its region. This

canid is not closely related to any other canid alive today, making it the sole member of

its genus [14]. There are many distinguishing features of this canid which include: long,

slim legs, distinctive golden-red fur, a dark mane extending from the nape down the midline of the back, a musky scent, and a distinctive howl [18, 5]. The fur of the maned wolf is a chestnut color with black upright hairs along the upper portion of the back and neck which form a mane, therefore, giving the species its name. White patches are found on the throat, underside, and inside the ears. Because of its long legs, it has acquired the nickname “a fox on stilts”. The legs of the wolf are so long that its height is greater than the length of its trunk. The average height is twenty-nine to thirty-four inches at the shoulder with a combined head and body length of forty-nine to fifty-two inches. The back legs are slightly longer than the front, therefore making downhill slopes awkward.

Since the long, slender legs are not very useful for digging, the maned wolf uses its teeth to dig out rodents from burrows. It also has large ears, which provide it with a keen sense of hearing, which is necessary when hunting rodents and other small mammals amongst the tall savanna grasses. The size of its ears also allows body heat to escape, which can

be very beneficial in the tropical temperatures of South America. The howl produced by

the maned wolf is quite different from the typical wolf. It is a deep-throated extended roar-bark, which is repeated at seven-second intervals [14].

9 The maned wolf is an omnivorous canid limited to a meat diet of primarily small mammals but may also feed on pampas deer, rodents, reptiles, ground birds, eggs, fish, frogs, and insects. However, it feeds on available plants as well. Although the maned wolf is classified under the taxonomic order Carnivore, plant intake can be as great as fifty-one percent of its total food intake. The plants that it feeds on include bananas, sugar cane, and many wild fruits. One of the wild fruits eaten by the maned wolf,

Solanum lycocarpum or “loberia”, is believed to have some therapeutic properties against the giant kidney worm, which is common in this species, and can often be fatal. The average weight of the maned wolf is fifty-seven pounds [14].

Maned wolves usually breed once a year, with a gestation period that is typically sixty-five days in length. Instead of digging dens, females bear their young in a nest of thick vegetation. For many years males were not believed to play a very active role in the rearing of their young. The female is still believed to be the primary caregiver, but recent studies suggest that the male may share in the pup-rearing duties. When born, the pups are brownish-gray and do not develop the characteristic long legs until several months after birth [14].

REVIEW OF ENRICHMENT IN MANED WOLVES

Several journal articles indicate that enrichment is vital to the lives of captive maned wolves and can have an affect on reproductive success. The information obtained by all of the journal articles helped create this study, and aided in the selection of the enrichment devices used.

10 One such study was Use of Behavioral Measures to Assess Reproductive Status in

Maned Wolves (Chrysocyon brachyurus) [18]. The objectives of this study were to

document changes in behavior during the breeding season in captive maned wolves in

order to determine if behaviors other than sexual could be used to distinguish nonbreeding from breeding pairs without necessarily observing copulatory behavior.

They also studied behaviors that could distinguish breeding pairs that did not produce young from those that did. The goal was clearly attained because the researchers were able to pick out distinct behaviors breeding pairs exhibited that nonbreeding pairs did not.

For example, breeding pairs, where the female was pregnant, exhibited agnostic behavior and marked their territory more frequently. Also, successful breeding pairs spent more time resting in close proximity.

Another journal article important to the present research was The Value of

Enrichment: A Comparative Systematic Evaluation of Enrichment in Two Highly Social and Endangered Canid Species, The African Wild Dog (Lycaon pictus) and Mexican

Gray Wolf (Canis lupus baileyi) [12]. The study examined the value of providing scents as a naturalistic form of enrichment for social carnivores by observing their reactions to novel scents. The placement of scented objects can stimulate curiosity and can also encourage natural behaviors. In addition, this experiment used Kong-Toys with a hollow center. A scent was placed on the toy before being presented to the animals. Analysis of this study has not been completed however, so the success of this method can not yet be determined.

A Survey of Maned Wolf Enrichment Practices in North American Zoos [5] was another important study about maned wolves and enrichment. Several surveys were sent

11 out to determine the types of enrichment that have been used for maned wolves. It was

found that the following items have been presented to the wolves: food, furniture, toys,

and olfactory stimuli. The researchers also examined the ways in which the wolves were

housed (paired, alone, with same/opposite sex, indoor/ outdoor, etc). It was found that

most wolves had access to both indoor and outdoor living areas, and had received some

type of enrichment. It was also established that the wolves that received enrichment

indicated some interest in it.

PROCEDURES

Before the wolves were presented with the enrichment devices, they were

observed for sixty-two minutes per day for a total of eleven days (Monday thru Friday,

Saturday if needed). Noted were how long the wolves were out of their den boxes, how

active they were, the types of objects or areas they sniffed in their sub-enclosures, their

play, how often they ate, how they interacted with each other, their movement in and out of the enclosure, and their elimination behaviors. This served as the baseline data.

The behavior of the wolves during each of the experiments was compared to the baseline data as noted previously. The behaviors with the different devices were also

compared to each other (which device elicited more interest). The level of interest was

measured by the amount of time the wolves spent around the objects, sniffing the objects,

playing with the objects, etc.

12 STUDY SUBJECTS

The focal study animals included an adult male and a yearling female housed in

the same compound. The male is about nine years of age, and the female is about a year and a half. There was no need to mark the animals because the female is somewhat taller

than the male and has darker markings as well. The wolves are fed commercial dog

kibble, as well as apples, bananas, sweet potatoes, rats, and bones. They are provided

with water throughout the day.

EXPERIMENT ONE: PLAIN BOX VERSUS COLORED BOX

The enrichment device used for this experiment was a regular, brown cardboard

box measuring 15 ¾” X 7 ¼” X 7 ¼” placed in the maned wolf enclosure and observed

sixty-two minutes per day for a total of four days. Each individual wolf was its own

control. The wolves’ interest in the box was observed by seeing if they smelled it, played

with it, moved it, or even tore it up. These activities, if observed, were timed. Once the

wolves lost interest in the box, it was replaced with another box, but this one was brown

with red shapes (squares/rectangles). This was created by cutting the shapes into the box

and covering them with red construction paper on the inside, and using nontoxic hot glue

to secure the paper. The purpose of this design was to ensure that the wolves could not

come in contact with the construction paper. Canids are said not to see color, but there

has been some indication by observers that a response to red exists. Again, the wolves

were observed for sixty-two minutes per day for a total of three days (when they lost

interest). The box was removed from the enclosure after each observation.

13 The first goal of this experiment was to discern if the presence of the box had any effect, positive or negative, on the behavior of the wolves. The second objective was to see if a change in color had a significant effect on the behavior of the wolves. The hypothesis is: if a plain, brown cardboard box is placed in the maned wolf enclosure, the wolves will interact a great deal initially, then interest will die down within three days, but replacing the plain, brown cardboard box with a box of a different color will elicit renewed interest in the box for up to an additional three days.

EXPERIMENT TWO: BOOMER BALL WITHOUT FOOD VERSUS WITH FOOD

The enrichment device used for this experiment is called a Boomer ball, which is a hollow ball, with four holes in it. The device was put into the wolves’ enclosure without food at first. Each individual wolf’s interactions with the device were timed. The wolves were observed for sixty-two minutes per day for a total of four days (until they lost interest). The device was taken out of the enclosure after each observation. The ball was cleaned with water if dirty, and would then be allowed to air-dry over night. Food was then placed into the center of the ball using disposable vinyl gloves, to minimize the transfer of human scent, and consisted of 100 grams of commercial high quality dog food, a fourth of an apple, sweet potato, and banana. This was observed for sixty-two minutes per day for a total of four days (until they lost interest). When food was placed inside the ball and rolled by the wolves, the food was dispensed. If the wolves showed little interest in the ball with food to begin with, an option was to smear the banana and sweet potato on the outside of the ball to discern if any additional interest would result.

14 The first objective for this experiment was to observe the differences in behavior of the wolves with and without the ball. The second goal was to observe the steps the wolves went through in getting food out of the ball, by rolling it, most likely, and to observe how much time it took them to do so. The hypothesis for the Boomer ball without food is: if a Boomer ball, without food, is placed in the maned wolf enclosure, the wolves will investigate the ball, and will most likely show little interest in it. The hypothesis for the Boomer ball with food is: if a Boomer ball, with food inside, is placed in the maned wolf enclosure, then the wolves will interact with the ball for several days.

They will learn how to roll the ball to remove food out of the ball in three days’ time.

EXPERIMENT THREE: PLAIN BOX WITHOUT FOOD VERSUS WITH FOOD

A plain brown cardboard box measuring 15 ¾” X 7 ¼” X 7 ¼” was placed inside the maned wolf enclosure and observed for sixty-two minutes for one day (until they lost interest). The wolves’ interest in the box was observed by seeing if they smelled it, played with it, moved it, or even tore it up. Once the wolves lost interest in the box, it was replaced with another plain, brown cardboard box, but this one had food on the inside and also smeared on the outside of it. One hundred grams of commercial high quality dog food and a fourth of an apple were on the inside, and a fourth of a banana and sweet potato were smeared on the outside. The wolves were observed for sixty-two minutes for three days (until they lost interest). Then, the difference in the amount of time investigating the two boxes was compared. The device was removed from the enclosure after each observation. Each individual wolf was its own control.

15 This experiment was designed to discern if the box still interested the wolves since they had already received it as an enrichment item. The second goal was to see if the wolves showed more interest in the box with food on and in it than they did when a regular box was first presented (experiment one). The hypothesis of this experiment is: if a plain, brown cardboard box is placed in the maned wolf enclosure a second time, the wolves will show little interest in the box, but by replacing it with a plain brown cardboard box with food on the inside and outside, the wolves’ interest will be renewed in the box for an additional three days.

RESULTS AND DISCUSSION

BASELINE DATA

Overall activity levels for the maned wolves can be seen in Figure 1. It was

observed that the female maned wolf was pretty much inactive, and spent most of her

time in the den box (could be due to weather conditions such as rain). The female is new

to the Center, so this also could explain the amount of time spent in the den box.

However, the female exhibited more of the hunter instinct than the male. When out of

the den box, she spent a great deal of her time hunting (most of the time successful),

lying around in the middle/back of the enclosure, or walking around in the back of the

enclosure. It was also observed that the female did not eat as often as the male. The

female always made sure that she kept her distance from the male (almost as if she were

afraid of him). Again, this could be due to her comfort level with the area and her

companion, and neighboring wolves since she is new to the Center.

16 The male was much more active than the female (did not seem to be affected by

weather conditions). He spent a great deal of time out of the den box, but did lie in the

open door den box frequently. When out of the den box, he spent much of his time

walking around the entire enclosure, eating, grooming himself (after eating usually),

urinating (raised leg urination) on trees, tall grasses, and in their drinking water, sniffing

trees and the ground, and lying around in any part of the enclosure. He was not observed

to be as successful a hunter as the female. He spent a good amount of time stalking prey,

but rarely caught anything. Since the male was not the best hunter, he would chase the

female whenever she caught something, and most of the time, would succeed at getting

whatever she had caught. This could possibly explain one reason why the female stayed

away from him. It was also observed that the male was not fond of the red wolves in the enclosure to the left of the maned wolf enclosure. Whenever he was near the fence that separated the two enclosures and the red wolves were also near it, the hair on the nape of his back would rise.

EXPERIMENT ONE: PLAIN BOX VERSUS COLORED BOX

Tables 1 and 2 show the amount of time spent with the enrichment devices during

this experiment and Figure 2 shows the change in overall activity levels. The hypothesis was: if a plain, brown cardboard box is placed in the maned wolf enclosure, the wolves will interact a great deal initially, then interest will die down within three days; but replacing the plain, brown cardboard box with a box of a different color will elicit renewed interest in the box for up to an additional three days. The first part of the hypothesis was supported. The wolves interacted a great deal with the box on the first

17 day, but their interest waned pretty quickly after that. The female spent a total of ten

minutes with the box on the first day, while the male only spent four (greatest amount of

time spent with any device for both wolves). On the second day, the male was more

interested in the box than the female. The third day showed lessening in interest by the

male, while the female was still uninterested. On the last day of observation the male’s interest was even less, but the female’s interest was sparked a little. As the hypothesis stated, the interest of the wolves would die down within a matter of a few days. The interactions with the device included: playing with it, tearing it up, sniffing it, rolling it, putting it in their mouth, opening it, urinating on it, digging at it, putting their food on top

of it, and biting it. The female was more interested in the box than the male, tearing the

box up completely.

The hypothesis stated that by exchanging the regular, brown cardboard box with a box with cut-outs of a different color, the wolves’ interest would be renewed. This did not happen, however. The wolves showed even less interest in the box with colored shapes than they did in the regular one. On the first day with the new box, the male spent hardly any time with it, and the female, none at all. The second day, the box proved to be even less interesting. The wolves spent no time with the box on this day. On the last day with the colored box, the male spent less time with the box than on the first, while the female still exhibited no interest. The change in color pattern clearly did not have any affect on the female, and did not seem to influence the male either; so, the second part of the hypothesis was not supported. The interactions with this device included: sniffing and urinating on it.

18 As for the overall behavior of the wolves during this experiment, there were some

changes (for results of T-Test, see Tables 7-14). During the first part of this experiment

(plain, brown box), the male still urinated (raised leg) on trees; however, now he was also urinating on the enrichment device. Another difference noted in his behavior was that he

would take food in his mouth, leave the eating area, and then lie down somewhere and eat it. During the time that the baseline data was taken, he would just eat in the eating area.

Also, the male howled several different times during this study, a behavior that was not found in the baseline data. Two other behaviors that were new were the male digging at the ground and jumping on top of the den box. The male’s behavior did not change very

much throughout the course of the second part of this experiment (box with cutouts).

However, one new behavior observed was that the male dug at the fence separating the maned and red wolves. This occurred while he was hunting (unsuccessfully). Again, he still urinated on trees and the enrichment device, and seemed to like to walk around the entire enclosure. His appetite was the same. He still liked to groom himself after eating.

In this part of the experiment, the male only laid in the middle of the enclosure. The only

objects he smelled were the ground and the enrichment device.

During the first part of this experiment (plain, brown box), the female displayed

several differences in her behavior. She became more active; however, this behavior

change did not constitute statistical significance (p=0.088, see Table 9). She was found sniffing the ground as well. She liked to walk around in the front of the enclosure and lie in the middle of the enclosure. There was a time that she was also found gaping at the male. On some days, she would be scared of the male and run away from him if he got too close. On another day, both the male and female seemed to be watching what the

19 other was doing, and the male seemed to be following the female. Her hunting was still successful. During the second part of this experiment (box with cutouts), the female’s behavior was not changed significantly. Her level of activity decreased drastically compared to the first part of this study, but did not reach statistical significance (p= 0.65, see Table 10). She was only out of the den box on one day of this part of the experiment, and she spent her time lying in the middle of the enclosure.

It was very obvious that a change in color of the enrichment device had no effect on the interest of the wolves. The presence of either enrichment device did not have a negative effect on the wolves’ behavior. However, the presence of the box did not really have a positive effect either, other than on the overall activity level of the wolves.

Compared to the baseline data, the male’s activity level increased every day of this experiment, and was statistically significant overall (p= 0.037, see Table 7). The female’s activity level increased five out of the seven days, but did not reach statistical significance (p=0.073, see Table 9).

EXPERIMENT TWO: BOOMER BALL WITHOUT FOOD VERSUS WITH FOOD

Tables 3 and 4 show the amount of time spent with the enrichment devices during this experiment and Figure 3 shows changes in overall activity levels. The hypothesis for the Boomer ball without food was: if a Boomer ball without food is placed in the maned wolf enclosure, the wolves will investigate the ball, and will most likely show little interest in it. This hypothesis was supported. On the first day the wolves were presented with the ball, the male’s interest was sparked, but very little, and the female was not interested in the device at all. The second day was not much different; however, the

20 male’s interest lessened, and the female’s interest was sparked a little. The third day was

worse yet; however, weather conditions (rain) could be an explanation for this. Both

wolves did not spend any time with the device on that day. On the last day, the male’s

and female’s interest increased from the second day of observation. The interactions with

the ball included: moving and smelling it.

The hypothesis for the Boomer ball with food was: if a Boomer ball, with food

inside, is placed into the maned wolf enclosure, then the wolves will interact with the ball

for several days. This hypothesis was not supported. The male was quite interested on

the first day of observation, and the female showed some interest as well. On the second day there was less interest from both wolves. The third day aroused a little more interest

in the male; however, the female’s interest decreased. On the final day of observation, the male’s interest increased compared to the second day of observation, and the female showed very little interest. The interactions with the ball included: smelling it, moving/rolling it (the male did this), biting it, urinating on it, and licking it. The male used his feet, as well as his nose to roll, but was not successful at getting food out of the ball. It seemed that he did not roll the ball far enough for the food to be dispensed (did not roll the ball around completely one turn). The male did, however, eat the food that fell out of the ball when the ball was thrown into the enclosure. Since there was little interaction with the ball, a second option was used: smearing food (bananas and sweet potatoes) on the outside of the ball. This yielded little change in the interactions.

As for the overall changes in the behavior of the wolves, some of their behaviors did not change when the device was introduced into the compound (for results of T-Test, see Tables 7-14). However, several differences were noted. During the first part of this

21 experiment (ball), the male was found walking mainly around in the back and front of the

enclosure. He still ate fairly often. While he still urinated on trees and the enrichment device, he was observed urinating in their drinking water. The male was also observed following the female around the enclosure. As for the second part of this experiment

(ball with food), the male was much more active; however, this behavior change was not at a statistically significant level (p=0.055, see Table 8). In this part of the experiment, the male seemed to prefer to lie in the front and middle parts of the enclosure. He also preferred to walk around the front of the enclosure. Again, the only object he sniffed was the ground. His hunting was still unsuccessful. He was observed grooming himself just like he did before, after eating. He was also observed to be eating grass. This behavior was not necessarily new because he was observed exhibiting this behavior on days when there was no device present (days between devices). He still urinated on trees, grass and the enrichment device, but he was also observed to be urinating on the den box. The male did exhibit some new behaviors, however. He would not let the female near the enrichment device at all, which could have affected her approach to the device. He seemed to guard the device, always watching it, as well as watching where the female was in relation to it. The male was observed chasing the female again, but this time he also barked at her. However, there was one day in this part of the experiment that the male and female seemed to get along, and even played together.

The female’s overall behavior also changed quite a bit. During the first part of the experiment (ball), she was observed walking around the front of the enclosure. She definitely behaved as is she was afraid of the male. On numerous occasions, she was observed running away from the male if he got too close. Her activity level increased a

22 fair amount from the last study (box with cutouts), but did not reach statistical

significance (p= 0.643, see Table 10). During the second part of this experiment (ball

with food), the female’s activity level seemed to increas even more, but still was not of

statistical significance (p= 0.094, see Table 10). As usual, she preferred to lie in the middle of the enclosure, but, it was observed that she liked to walk around in the front

and back areas of the enclosure. She ate a little more than she had during previous

studies, but like the male, was also observed eating grass. The female was observed

stalking, but she never chased anything down or caught anything. She paced around the

enclosure, a behavior that was new to this study.

Overall, this enrichment had a more indirect effect on the behavior of the wolves

than direct. The female’s general activity level showed improvement on five out of the

eight days (even though she did not interact with the ball much) but was not statistically

significant (p= 0.072, see Table 9). However for the second part (ball with food) of this

experiment, compared to the baseline data, her activity level did increase a statistically

significant amount (p= 0.021, see Table 9). She did not show a significant amount of

interest in any of the devices, but appeared to prefer the Boomer ball over any of the other devices, judging from her activity level. A possible reason for her small amount of interaction could be that the male did not let her get very close to the device. He guarded

the ball, and she knew not to come near it. This could also be a possible explanation for

her pacing. She couldn’t get to the ball, therefore paces back and forth. The male’s

activity level increased four out of the eight days, but was not of statistical significance

(p= 0.355, see Table 7). Unlike the female, he did interact with the ball some, and his general activities were the same behaviors he expressed without the ball in the enclosure.

23 EXPERIMENT THREE: PLAIN BOX WITHOUT FOOD VERSUS WITH FOOD

Tables 5 and 6 show the amount of time spent with the enrichment devices during

this experiment and Figure 4 shows changes in overall activity levels. The hypothesis was: if a plain, brown cardboard box is placed in the maned wolf enclosure a second time, the wolves will show little interest in the box, but by replacing it with a plain, brown cardboard box with food on the inside and outside of it, the wolves’ interest will be renewed in the box for an additional three days. The first part of this hypothesis was supported. The male and female both exhibited very little interest in the box the day that it was presented. It was not necessary to present the box a second day since the wolves obviously did not show interest in the device. The only interaction the wolves had with the box was sniffing it.

The second part of the hypothesis was not supported, however. The wolves still showed little interest in the food-modified box. On the first day the box with food was presented, the male was very interested in the box, but the female was not. The second day proved to be better for the female, but the male’s interest decreased. On the last day of observation, the male’s interest level was pretty low compared to the first day of observation, and the female, like the first day, did not demonstrate any interest. The interactions with this box included: smelling it, biting it, digging at it, eating the contents, putting their nose inside of it, licking it, moving it, and urinating on it. Throughout this study, the wolves would often walk by the box, sometimes looking at it, but would do nothing with it.

Several differences in the behavior of the wolves were also noted in this experiment (for results of T-Test, see Tables 7-14. During the first part of this

24 experiment (plain, brown box), the male’s activity level decreased a little from the last

experiment (ball with food); however, the statistical significance could not be determined

because it violated a rule of the T-Test (see Table 8). He was observed lying around the

middle and front areas of the enclosure. He seemed to prefer to walk in the front part of

the enclosure, and he still urinated on trees, the device, the grass, and in their drinking

water. A new behavior observed was that he sniffed the female’s urine and licked it. In

addition, he was observed sniffing the fence between the maned and Mexican gray wolf

enclosures. The male also seemed restless during this part of the study. During the second part of this experiment (box with food), the male’s activity level increased

compared to the first part of this experiment, but again, the statistical significance could

not be determined because it violated a rule of the T-Test (see Table 8). It was observed

that he preferred to walk and lie in the middle and front areas of the enclosure. He still

urinated on trees, grass, and the device, and the only object in the enclosure that he

sniffed was the grass. Some new behaviors were observed in the male, such as the fact

that he would not go near the enrichment device until the keepers had left the area. He

would watch them until they were gone, and then go to the device. The male seemed

restless in this part of the study as well (could be due to the fact that his girl pups, born

almost two years ago, left the Center on the second day of the experiment). He was also

observed howling. Lastly, the male growled at the female. He was by the den box and

she came out, apparently startling him, which is a possible explanation for why he

growled.

During the first part of this experiment (plain, brown box), the female’s activity

level decreased compared to the last experiment (ball with food). The statistical

25 significance could not be determined because it violated a rule of the T-Test (see Table

10). She was observed walking in the front area of the enclosure and standing in the front

and middle of the enclosure. The female did not sniff anything other than a tree. During

the second part of this experiment (box with food), the female’s activity level increased,

but again the statistical significance could not be determined because it violated a rule of the T-Test (see Table 10). She was observed lying in the middle of the enclosure and

standing in the front. She only sniffed the grass in the enclosure. The female and the

male engaged in a play chase. While running from him, she did not seem to be afraid of

him, but was actually playing with him, which was quite unusual.

It was found that the wolves expressed more interest on the first day when presented with a plain box (first experiment) than on the first day when presented with a plain box without food (experiment three). Surprisingly, it was observed that the wolves were not really more interested in the box with food than they were with the box without food. A possible reason for this is that the wolves already had food, so there was no reason to work for more. A solution for this would be not to feed the wolves until after the observation. As for overall amount of time spent with the devices, compared to experiment one, the wolves showed more interest on the first day they were presented with the plain box than they were on the first day when presented the box with food.

Compared to the baseline data, the female’s activity level increased three out of the five days in this experiment; however, statistical significance was not reached (p= 0.177, see

Table 9). The male’s activity level increased two out of the five days, but again, statistical significance was not obtained (p= 0.545, see Table 7).

26 Conclusion

During the course of this study, the observer spent a total of thirty days doing

thirty-one hours of observations (1860 minutes). When glancing over the amount of time

the wolves spent with the devices, it doesn’t appear that the enrichment affected them.

However, while the enrichment devices themselves may not have been interacted with

directly, changes in the activity levels of the male and female were noteworthy. The

female was not very active during the baseline data, but her activity level increased

throughout the experiments, and reached levels of statistical significance (see Tables 9-

10). Her relative inactivity during the baseline data observations could have been due to the fact that she was new to the enclosure, and to the Center. A possible reason for her increase in activity level was that the devices helped encourage her to investigate her surroundings, or it could have given her a reason to be out of the den box. The change in the male’s activity level was not substantial, but did reach statistical significance in a few areas (see Tables 7-8). He was very active during the baseline observations, so a change noted was a slight decrease in his activity for a few days throughout the experiments.

However, there were a few days when his activity level increased from baseline, such as in experiment one (p= 0.037, see Table 7). He was still almost always more active than the female. As for which device elicited the most interest from the wolves, the plain box from experiment one received the most attention (see Tables 1-6).

It was thought that a change in elimination (frequency) would occur. For the male however, this did not occur during any of the experiments. A possible reason for this is that during the baseline data, the male eliminated very often throughout the observations. Statistical significance was found for observation periods in-between the

27 experiments (p= 0.039, see Table 11). As for the female, statistical significance was not

reached as expected in the individual experiments. However, when comparing all three

experiments to the baseline data, statistical significance was reached (p= 0.009, see Table

13).

After the experiments were completed, the wolves’ activity levels in all

experiments were compared to one another as shown in Tables 8, 10, 12, and 14. The

male’s activity level differences reached statistical significance when the Boomer ball

was compared to the plain box (first presentation) and when it was compared to the colored box (p= 0.047, p= 0.047, see Table 8). The female’s activity level differences did not attain statistical significance when the experiments were compared to each other

(see Table 10). As for the wolves’ elimination changes when compared to all experiments, there was no statistical significance found for either the male or female.

An interesting behavior was observed throughout the course of this study. When the researcher arrived, and the male was out of the den box but the female was not, the male would go into the den box for a few seconds and then come back out. A few moments later, the female would come out of the den box. She would sit in the front of the enclosure, scratch, and then walk to the back of the enclosure and eat grass, or sniff the ground along the fence. This occurred in all three experiments.

If this experiment were to be continued, a possible new device would be a log

with different scents placed on it, such as food scents, urine from other animals, etc. In

addition, Kong toys would also be a possibility, whether placing food inside of them, or

placing scents on them. Modification stated earlier (not feeding the wolves all of their

food until after observations) would be used. Unfortunately, the male wolf that was

28 observed during this study died on December 24, 2007, precluding research with the

same pair of wolves.

ACKNOWLEDGEMENTS

First and foremost, I would like to thank my mentor, Dr. Susan Lyndaker

Lindsey, for the opportunity to conduct this research and for agreeing to be my mentor.

She spent countless hours helping me with this study and writing my paper. Her help, guidance, and knowledge have been invaluable. Secondly, I would like to thank the keepers at the Wild Canid Survival and Research Center. I definitely could not have done this study without their help. They assisted in preparing the food for experiments two and three, and also helped in putting the devices in the enclosure as well as retrieving them. Last, but not least, I would like to thank my Authentic Science Research teacher,

Mrs. Cheryl Apperson for all of her help with this paper. She guided me throughout my entire study, helping me find journal articles, preparing for presentations, and so on. This study would not have been possible without her.

29 TIME MANED WOLVES SPENT (IN MINUTES) WITH ENRICHMENT DEVICES

Table 1. Experiment One: Plain Box Table 2. Experiment One: Colored Box GENDER DAY 1 DAY 2 DAY 3 DAY 4 GENDER DAY 1 DAY 2 DAY 3

MALE 4.00 3.50 2.13 0.75 MALE 0.25 0.00 0.22

FEMALE 10.00 0.00 0.00 0.08 FEMALE 0.00 0.00 0.00

Table 3. Experiment Two: Boomer Ball Table 4. Experiment Two: Boomer Ball with Food GENDER DAY 1 DAY 2 DAY 3 DAY 4 GENDER DAY 1 DAY 2 DAY 3 DAY 4

MALE 0.90 0.70 0.00 0.88 MALE 1.60 0.67 1.00 1.25

FEMALE 0.00 0.05 0.00 0.15 FEMALE 0.58 0.08 0.00 0.10

Table 5. Experiment Three: Plain Box Table 6. Experiment Three: Box with Food GENDER DAY 1 GENDER DY 1 DAY 2 DAY 3

MALE 0.68 MALE 2.95 0.40 0.83

FEMALE 0.33 FEMALE 0.00 0.42 0.00

30 TIME MANED WOLVES SPENT ACTIVE (IN MINUTES): T-TEST

Table 7. Male Activity Level Base vs. Experiment One: Plain Box vs. p= .037 Colored Box Base vs. Experiment Two: Ball vs. Ball p= .355 not significant (ns) with Food Base vs. Experiment Three: Plain Box vs. p= .545 ns Box with Food Base vs. Plain Box p= .037 Base vs. Colored Box p= .037 Base vs. Ball p= .099 ns Base vs. Ball with Food p= .162 ns Base vs. Plain Box (second presentation of Could not complete. Violates rules of device) T-Test. Base vs. Box with Food p= .415 ns Base vs. Experiment One, Two, and Three p= .871 ns Base vs. In- between all Experiments p= .797 ns

Table 8. Male Activity Level Plain Box vs. Colored Box Could not complete. Violates rules of T-Test. Plain Box vs. Ball p=.047 Plain Box vs. Ball with Food p=.320 ns Plain Box vs. Box with Food p=.423 ns Colored Box vs. Ball p=.047 Colored Box vs. Ball with Food p=.320 ns Colored Box vs. Box with Food p= .423 ns Ball vs. Ball with Food p=.055 ns Ball vs. Plain Box (second presentation of Could not complete. Violates rules of device) T-Test. Ball with Food vs. Plain Box (second Could not complete. Violates rules of presentation of device) T-Test. Plain Box (second presentation of device) Could not complete. Violates rules of vs. Box with food T-Test. Ball vs. Box with Food p=.060 ns Ball with Food vs. Box with Food p=.789 ns

31 Table 9. Female Activity Level Base vs. Experiment One: Plain Box vs. p= .073 ns Colored Box Base vs. Experiment Two: Ball vs. Ball p= .072 ns with Food Base vs. Experiment Three: Box vs. Box p= .177 ns with Food Base vs. Plain Box p= .088 ns Base vs. Colored Box p= .531 ns Base vs. Ball p= .687 ns Base vs. Ball with Food p= .021 Base vs. Plain Box (second presentation of Could not complete. Violates rules of device) T-Test. Base vs. Box with Food p= .338 ns Base vs. Experiment One, Two, and Three p= .012 Base vs. In- between all Experiments p= .164 ns

Table 10. Female Activity Level Plain Box vs. Colored Box p=.648 ns Plain Box vs. Ball p=.131 ns Plain Box vs. Ball with Food p=.683 ns Plain Box vs. Box with Food p= .272 ns Colored Box vs. Ball p= .624 ns Colored Box vs. Ball with Food p= .792 ns Colored Box vs. Box with Food p=.240 ns Ball vs. Ball with Food p=.094 ns Ball vs. Plain Box (second presentation of Could not complete. Violates rules of device) T-Test. Ball with Food vs. Plain Box (second Could not complete. Violates rules of presentation of device) T-Test. Plain Box (second presentation of device) Could not complete. Violates rules of vs. Box with food T-Test. Ball vs. Box with Food p=.436 ns Ball with Food vs. Box with Food p= .311 ns

32 MANED WOLF ELIMINATION BEHAVIOR: T-TEST

Table 11. Male Elimination Behavior Base vs. Experiment One: Plain Box vs. p= .136 ns Colored Box Base vs. Experiment Two: Ball vs. Ball p=.360 ns with Food Base vs. Experiment Three: Plain Box vs. p= .338 ns Box with Food Base vs. Plain Box p= .138 ns Base vs. Colored Box p= .491 ns Base vs. Ball p= .832 ns Base vs. Ball with Food p= .165 ns Base vs. Plain Box (second presentation of Could not complete. Violates rules of device) T-Test. Base vs. Box with Food p= .732 ns Base vs. Experiment One, Two, and Three p= .068 ns Base vs. In- between all Experiments p=.039

Table 12. Male Elimination Behavior Plain Box vs. Colored Box p=.936 ns Plain Box vs. Ball p=.686 ns Plain Box vs. Ball with Food p=.824 ns Plain Box vs. Box with Food p=.583 ns Colored Box vs. Ball p= .453 ns Colored Box vs. Ball with Food p= .969 ns Colored Box vs. Box with Food p=.667 ns Ball vs. Ball with Food p=.167 ns Ball vs. Plain Box (second presentation of Could not complete. Violates rules of device) T-Test. Ball with Food vs. Plain Box (second Could not complete. Violates rules of presentation of device) T-Test. Plain Box (second presentation of device) Could not complete. Violates rules of vs. Box with food T-Test. Ball vs. Box with Food p=.662 ns Ball with Food vs. Box with Food p= .504 ns

33 Table 13. Female Elimination Behavior Base vs. Experiment One: Plain Box vs. p=.172 ns Colored Box Base vs. Experiment Two: Ball vs. Ball p=.351 ns with Food Base vs. Experiment Three: Plain Box vs. p= .058 ns Box with Food Base vs. Plain Box p= .182 ns Base vs. Colored Box Could not complete. Violates rules of T-Test. Base vs. Ball Could not complete. Violates rules of T-Test. Base vs. Ball with Food p= .391 ns Base vs. Plain Box (second presentation of Could not complete. Violates rules of device) T-Test. Base vs. Box with Food p= .184 ns Base vs. Experiment One, Two, and Three p= .009 Base vs. In- between all Experiments Could not complete. Violates rules of T-Test.

Table 14. Female Elimination Behavior Plain Box vs. Colored Box p=.182 ns Plain Box vs. Ball p=.182 ns Plain Box vs. Ball with Food p=.537 ns Plain Box vs. Box with Food p=.723 ns Colored Box vs. Ball Could not complete. Violates rules of T-Test. Colored Box vs. Ball with Food p= .391 ns Colored Box vs. Box with Food p=.184 ns Ball vs. Ball with Food p=.391 ns Ball vs. Plain Box (second presentation of Could not complete. Violates rules of device) T-Test. Ball with Food vs. Plain Box (second Could not complete. Violates rules of presentation of device) T-Test. Plain Box (second presentation of device) Could not complete. Violates rules of vs. Box with food T-Test. Ball vs. Box with Food p=.184 ns Ball with Food vs. Box with Food p= .373 ns

34 MANED WOLF ACTIVITY LEVEL

62 60 58 56 54 52 50 48 46 44 42 40 38 36 34 TIME SPENT ACTIVE 32 30 (MINUTES) 28 Male 26 24 Female 22 20 18 16 14 12 10 8 6 4 2 0 One Three Fi ve Seven Ni ne Eleven DAY Figure 1. Baseline Activity Level

62 60 58 56 54 52 50 48 46 44 42 40 38 36 34 TIME SPENT ACTIVE 32 MALE (PLAIN) (MINUTES) 30 MALE (COLORED) 28 26 FEMALE (PLAIN) 24 22 FEMALE (COLORED) 20 18 16 14 12 10 8 6 4 2 0 ONE TWO THREE FOUR DAY Figure 2. Experiment One: Plain Box Versus Colored Box Activity Level 35 62 60 58 56 54 52 50 48 46 44 42 40 38 36 34 MALE (WITHOUT) TIM E SPENT ACTIVE 32 30 MALE (WITH) (IN MINUTES) 28 26 FEMALE (WITHOUT) 24 22 FEMALE (WITH) 20 18 16 14 12 10 8 6 4 2 0 ONE TWO THREE FOUR DAY Figure 3. Experiment Two: Ball without Food Versus with Food Activity Level

62 60 58 56 54 52 50 48 46 44 42 40 38 36 34 MALE (WITHOUT) TIM E SPENT ACTIVE 32 (IN MINUTES) 30 MALE (WITH) 28 26 FEMALE (WITHOUT) 24 22 FEMALE (WITH) 20 18 16 14 12 10 8 6 4 2 0 ONE TWO THREE DAY

Figure 4. Experiment Three: Plain Box without Food Versus With Food Activity 36 Level MANED WOLF ELIMINATION BEHAVIOR 7

6

5

4 NUMBER OF ELIMINATIONS MALE 3 FEMALE

2

1

0 ONE THREE FIVE SEVEN NINE ELEVEN DAY Figure 5. Baseline Elimination

7

6

5

4 NUMBER OF ELIMINATIONS 3 MALE(PLAIN) MALE( COLORED) 2 FEMALE(PLAIN) FEMALE(COLORED) 1

0 ONE TWO THREE FOUR DAY Figure 6. Eeperiment One: Plain Box Versus Colored Box Elimination

37 7

6

5

4 NUMBER OF ELIMINATIONS 3 MALE(WITHOUT) MALE(WITH) 2 FEMALE(WITHOUT) FEMALE(WITH) 1

0 ONE TWO THREE FOUR

DAY

Figure 7. Experiment Two:Ball without Food Versus with Food Elimination

7

6

5

4 NUMBER OF ELIMINATIONS 3 MALE(WITHOUT) 2 MALE(WITH) FEMALE(WITHOUT) FEMALE(WITH) 1

0 ONE TWO THREE DAY

Figure 8. Experiment Three:Plain Box without Food Versus with Food Elimination 38 BIBLIOGRAPHY

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41