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Escaped Wolf Dispatched at Minnesota Zoo as a Last Resort–Interview with Tony Fisher

Last week an endangered Mexican wolf was dispatched at one of the nation’s leading captive conservation centers in Apple Valley, Minnesota. A decision to resort to lethal measures was made expeditiously and according to protocol after a the wolf scaled an 8 foot secondary confinement barrier that typically precludes an animal from entering a public area. 

Contributing Editor and Curator Jordan Schaul interviews Tony Fisher (Animal Collections Manager at the Minnesota Zoo) to learn what exactly transpired and how the Zoo arrived at the unfortunate decision to dispatch this wolf.

This past weekend I was standing in front of Kodiak bear cub exhibit at approximately 7:00 PM in the evening (Alaska time) when I observed a 140lb female cub snap a dead cotton tree at a back corner of it’s enclosure. The tree proceeded to fall in the direction that it had been pushed.  The common fence that separated the cub and its exhibit-mate from two adult American black bears broke its fall leaving the tree at a 60 degree angle from the ground.

Fortunately, the size of the dead tree was such that it precluded the bear cubs from using it as a means to climb out of the enclosure into the black bear pen. Regardless, it still landed up against an electric wire at the very top of the fence.

This created an additional problem because anything touching the wire may short-circuit the “electric fence” impeding it from admitting siemens (S) of electrical current used to deter animals from climbing the fence.

Once an animal learns that something associated with the fence produces a shock, the fence itself becomes a psychological barrier, as the current is not strong enough to incapacitate a medium to large size ungulate or carnivore, or primate for that matter. I know because I have been shocked more than one electric fence wire myself. It’s a jolt that can wake you up in the morning, but by no means does it render one incapacitated. 

I could see that this tree was something I could likely move by myself. As the curator I had the authority to go into the enclosure with the cubs and attempt to dislodge the tree. Fortunately I still work with them regularly without a barrier between myself and them–what we call free contact management.   This was very convenient. Otherwise I would have had to issue a recall command to bring them off exhibit which would have extended the time at which some of the bears would have been confined without an operating electric fence. I was also lucky that I was right there and watched the event unfold in front of me. Hence, I could work expeditiously before the cubs even attempted to use the tree to climb into an adjacent enclosure.  I didn’t even give the bear cubs time to become curious. The situation required an immediate response.

In this case many factors influenced a favorable outcome including the fact that I had just fed the cubs on exhibit and they were preoccupied with eating. Keep in mind that I had to push the tree off the fence with the cubs in proximity and needed to make sure that I didn’t exacerbate the situation or drop the tree on one the bears, despite their agility.

The one thing that was alarming in this case was that the visitors who observed the tree fall  were entirely captivated by the feeding cubs, and were not the least bit startled by the fact that a potential escape route for the bear cubs had just presented itself. They also weren’t concerned that there was breach of perimeter barrier once the tree had fallen on the clearly marked wire.  Keep in mind that electrical current may have been disrupted around the entire enclosures because wire stretched the length of the common fence on both sides.

My guess is that noone would have notified a staff member untill they actually saw a bear on its way up and over the fence.  Imagine what could have transpired if the brown bear cubs encountered our more docile black bear male. Sure he is a third larger, but these two raucous cubs would have been a formidable match for him. On the other hand the female black bear would have been a formidable opponent to take on one of the cubs.

These two orphaned “grizzly” cubs are headed to Sweden next year.  I am very much endeared to them, having worked closely with them since they arrived as two terrified and volatile 80 pound balls of fur. Fellow staff members and regular visitors are also very attatched to them. As an organization we are ultimately responsibile for their welfare. The Alaska Department of Fish & Game tasked us with a responsibility that we consider to be a privilege. We have to provide for them and eventually get them safely to their permanent home in Europe where a new facility is being constructed for them. 

I did not have time to tranquilize four bears, assuming I could even get close enough to them to dart them as they romped through a five acre temporary holding pen.  A confrontation could have escalated and been over in a third the time it would take for a sedative to have an effect.  When I mean “over” the animals could have inflicted life threatening wounds to each other requiring the immediate need to dispatch  (i.e., euthanize) all four animals with fire arms.

Keep in mind that the physiological state of an excited and perhaps highly agitated animal influences the induction time of these drugs used  in chemical immobilization.  Even “superconcentrated” drugs used as central nervous system suppressants take time  to chemically restrain an animal.  The operator of the dart projector (e.g., blow gun) must also understand and have access to scenario-specific and species-specific drugs in a timely manner. The operator must also be able to target an injection site safely and appropriately allow time for the absorption of a tranquilizing agent.  

The point that I want to make are that the psychological state and physiological condition of the animal and that of the visitor are often key to a successful outcome and it is the role of animal care team to be as decisive as possible in a situation that threatens either animal or human life.   If one could ensure that all visitors would act responsibly and appropriately follow directions, it is probably true that animal care managers could refrain from ever using lethal means, just as they could if one could ensure that all animals at-large could remain calm. We don’t have that luxury, and so on occassion we have to resort to making difficult choices in a matter of seconds.  Zoos are prepared to make these difficult decisions. They take under consideration a number of factors and they do so with incredible instinct  and protocol.  The last resort is to take the life of an animal, but a captive animal, particulalry a large carnivore, regardless of species-specific demeanor is a potential threat to human saftey at a public venue.  

The Minnesota Zoo is staffed with highly qualified clinical veterinarians and experienced animal keepers, managers and curators.  For routine ‘knockdowns,’ be it a health exam or need to treat a tooth abcess they are prepared to use sedatives, analagesics and muscle relaxants to anesthetetize an animal.  They can even use this cocktail of pharmacological agents with an animal on exhibit, if need be, or more typically in isolated holding or at the zoo’s veterinary hospital.  These planned or unplanned ‘knock downs’ still require an allotment of time for an animal to be tranquilized or induced into a plane of tranquility with or without the use of analgesics and muscle relaxants.

Last week a Mexican gray wolf scaled an 8ft.  fence of an enclosure at the Minnesotta Zoo in Apple Valley, Minnesota. Once over the fence the animal had access to public walkways. Forget that it was a summer day with a thousands of visitors strolling by the exhibits.

Animals do not leave their enclosures without extremely strong provocation or without an extremely strong attractant like a potential mate or perhaps strong social stimuli like a competing social unit for that potential mate.  Their enclosure is their territory and captive animals typically feel vulnerable or uncomfortable outside of their enclosure.

Hence, their first impulse is to return to that enclosure by all means possible, unless an overiding stimulus draws them away.   Captive animals are much less afraid of people than wild animals and therefore they provide a potential threat to anyone that gets between them and the stimulus or their return to their enclosure. Furthermore, captive-born animals are even less afraid than wild-born animals, like the orphaned brown bear cubs who although tractable retain a fear of people which affords me some liberties from a behavioral management standpoint.
Interview:  Tony,
I’d first like to extend my condolesnces to you and your staff at the Minnesota Zoo. As unfortunate as this  incident was, I think that it is important that a zoo can demonstrate that human saftey is imperative. People should continue to feel comfortable visiting conservation, education, and research centers as a recreational activity for their families.  I think you achieved this objective, despite the terrible circumstances.

When I worked with wolves as a keeper at another midwestern zoo in the late 1990’s, we fortunately avoided what could have ended just as tragically as this incident did. 
A gentleman attempted to repel off of a bridge into a wolf exhibit just before closing.  Having been in the enclosure with the pack I was fairly certain that these wolves would do everything they could to avoid the perpetrator. As unpredictable as animals can be there were somethings I was privy to. I knew specific individuals in the pack to some degree working the area as a relief keeper. I knew the social dynamics of the pack at the time of the event (e.g., who was subordinate to whom) and hence, something about individual stress levels including heightened sensitivities of the collective pack members. For example, given time of day and number of people in the park and so on there were some stressors that would not exacerbate the situation.
None-the-less, a call had been made to our security base which set up a chain of events according to protocol.  I was prepared for our rifle team to take lethal action if my colleague was unable to recall the wolves into their holding areas. I was at the other side of the zoo exhibit area which itself is as big as some small zoos At the time we did not have cell phones–we did have radios and corresponded with all involved parties in a timely fashion.  Fortunately the perpetrator did not land in the exhibit–he missed it entirely and I believe was immediately taken in to custody.
Jordan Schaul: Can you tell me about your wolf collection, the animal that escaped and how and why you believe the animal escaped?
Tony Fisher: It appears that the escaped wolf was aggressively trying to enter an enclosure with two other wolves.  We recently received two Mexican wolves from the Dakota Zoo, due to an imminent flooding threat of the Missouri river. They asked us to take their wolves on a temporary basis until their situation stabilized. These two wolves were in the adjacent enclosure to our lone male and there was evidence that he was biting at the chain link fence that was nearest to the Bismarck pair.  He evidently found a section of fence that was missing some connectors, at the top of the enclosure where it joined the mesh cover. After bending back a piece of fence the size of a football, he forced his way through and entered the adjacent secondary containment area.  He was spotted soon after this by zoo staff and was seen pacing the common fence that separated him from the Bismarck wolves.  
Zoo staff immediately made preparations to tranquilize or net this lone wolf from the secondary containment area. Staff members were positioned near the containment area, getting ready to dart and transfer the animal when he decided to jump the eight foot secondary fence and run towards the public walkway.
The zoos’ emergency Animal Escape Policy was immediately put into action when the wolf escaped the secondary containment area.  The public was cleared from the walkways towards enclosed buildings, perimeter gates were locked shut, keepers gathered nets and capture equipment, and sharpshooter team members responded to the scene with firearms.
The wolf ran down the public pathways for several hundred yards and was next seen in front of the bison exhibit and was heading in a direction that would have taken him to a more populated section of the zoo or potentially escape under one of the several perimeter fence gates.  A zoo sharpshooter quickly intercepted the intended travel direction of the wolf and the decision was immediately made to dispatch the animal before he could potentially mix with the many school groups present or escape the zoo site into a highly populated housing area.  The shot was taken with no public in the area and in the direction of a solid background. 
Jordan Schaul: What is the Minnesota Zoo’s animal escape protocol?
Tony Fisher: The wolf was recaptured according to the Minnesota Zoo Animal Escape policy that specifies firearms should be used on wolves if there is a potential danger to humans or escape from zoo site may be imminent.
Jordan Schaul: You decided to use lethal force to deal with this incident. How did you come to this decision? Was the scenario executed as planned?
Tony Fisher: Yes, it was necessary to use firearms to insure the wolf did not travel into a populated area of the zoo, injure other zoo animals, or escape from zoo site. The zoo was busy that morning with thousands of school group kids and families in attendance.  This animal was not displaying aggression to humans as of yet, but could have easily become confined unintentionally by an innocent visitor in one of the many tight spots in the direction that he was heading. The result may have been fear and hostility towards whomever stood in his way towards freedom.
Tranquilizers would not have been an effective tool for controlling this animal.  Quick response was necessary for the best chance of success.  This wolf was moving fast and quickly learning to avoid zoo staff.  Tranquilizer darts are often inaccurate, slow-moving, and unreliable.  Adrenaline in the system of an excited animal can metabolize the drugs leaving little effect to immobilize.  A partial dose or a dart that bounces off a potentially aggressive animal can do more harm than good.  Firearms were the best choice for quick control in this situation. If the zoo was not open, or he had headed off in a different direction, we may have had or been able to use other control methods.
The wolf was controlled quickly and efficiently by staff.  I don’t think you can ever plan every possible escape scenario for zoo animals but we have spent a lot of time and effort being prepared.  Our sharpshooters have taken firearms safety courses and regularly qualify with the weapon proficiency. We routinely hold animal escape drills and have tested staff with many different escape possibilities. In fact, a wolf escape was one of our drills a few years ago. I think it was because of all our past drills that staff was able to act so quickly and efficiently.  However, if we had truly been able to act as planned, we would have captured the animal with tranquilizers while it was still held within the secondary containment fence.  That would have been a better outcome. 
Jordan Schaul: Are you surprised by some of the public outcry?
Tony Fisher: Not really.  I think we would have been criticized no matter what we would have done.  If we had been lucky enough to successfully tranquilize the wolf in front of the bison exhibit, people would have questioned why we had taken the chance on it getting away. If it had escaped zoo site, hurt other animals or people, the public outcry would have been justifiably much louder.
In the end, we did our job as zoo professionals that hold potentially dangerous animals.  We have an obligation as a zoo and to the communities in which we reside. Public safety and the safety of the entire animal collection must have the highest priority.  We did what absolutely had to be done and the authorities that regulate us agree with that.    

Jordan Schaul: What measures might you take to prevent this kind of escape in the future?
Tony Fisher: We need to look over our animal enclosures more closely, especially after the winter we just had.  The big snowfalls weighed heavily on all the chain link roof areas and broke some of the attachment anchors that normally stay in place.  Our keepers are now checking everything over.  And it’s not just enough to look at it, you have to physically grab a hold of mesh panels and shake them to reveal any weak spots.  When captive animals become motivated to get out, that’s when they’ll put your containment areas to the test.  You can’t get complacent with this stuff and think that just because it’s held for ten or twenty years for this species, it’ll hold today as well. 
Jordan Schaul:  How are the area keepers and other staff doing along with any animals co-habitating the exhibit?

Tony Fisher: Everyone feels sad about this incident.  The last thing we want to do is destroy one of our animals.  This wolf was born here eight years ago and the keepers cared about him and respected him as much as any other animal in their care.  However, I feel that the entire staff is unified about our decision to use firearms and gain quick control over a bad situation.  Everyone who works with potentially dangerous captive animals knows the alternative could have been much worse.  
Jordan Schaul: Do you have any suggestions for other institutions who may one day encounter a similar scenario?
Tony Fisher: Be prepared.  I think it’s easy to have a cavalier attitude about animal escape drills but I do believe that is what prepared us to react so quickly, and minutes matter in a situation like that.  Animals are smart and it doesn’t take long for them to sense pressure from staff and start to react accordingly.  Every minute that goes by, they’re learning. An animal escape that could have been controlled within the first few minutes can easily turn into a recovery that takes days, weeks, or maybe never.
We also learned to never fully trust your containment barriers.  Ultimately it was our fault that the wolf got out in the first place.  Our barrier failed because we didn’t check it well enough.  We regret that the animal had to be destroyed because of our mistake.


  1. shaiane
    December 12, 2012, 6:52 am

    omg they shouls always have a secong fence about a metre,metre and a half away so if one does go down there is another standing in the way of the animal