Bison Behavioural Management and Handling Facilities Design

General considerations

Any reasonable attempt to design and construct handling facilities for bison should begin with a solid understanding of normal bison behaviour and tendencies. Many of us assume that bison are wild creatures. In my opinion, this assumption is misleading. I believe that free ranging bison behave the way they do because of their environment. Bison raised on ranches or farms can behave very differently than bison in wild herds, simply because they have been taught to react to human interaction without reverting to instinctive behaviour.

However, it is important not to deceive ourselves. Bison are extremely athletic, powerful and potentially aggressive. Any person who chooses to place themselves inside a penning system at ground level with the bison to handle them should proceed only if they understand the behaviour of bison, those features of the handling system that provide safety, and is confident that others on the handling team know how, and are willing, to react appropriately in situations where the safety of a team member is threatened.

Working at ground level in sorting pens with bison is not realistic when dealing with wild bison assembled for some reason, or when attempting to work with ranch or farm raised bison that have never been subjected to training. This is especially true when such bison are handled in a pen system without design features that provide protection or means of escape for the handler.

Systems designed for handling wild bison or to eliminate direct exposure of the handler to bison usually work well to protect the handlers but they do not necessarily protect the bison from injury while being assembled, sorted or processed. Facilities designed to handle ranch or farm raised bison without any direct exposure of the handler to the bison, should incorporate protected walkways in, around, or above the system. Gates should be manipulated remotely with pulleys, levers, or hydraulics but never directly by hand.

On the other hand, if the facility is designed to reduce the risk of bison being injured or killed while being handled, and the handlers are willing to be at ground level in the pens and alleyways with them, then bison handlers must accept the risk that personal injury or death may occur at any point in the handling process. This sounds very serious but in fact farmers and ranchers make these decisions consciously or subconsciously every time they enter a pasture, corral, barn, or stall to work with large animals of every species.

Bison are distinct from other species of ranch-raised stock in that they revert very quickly to instinctive behaviour when they perceive threats or are frightened. For the purposes of these discussions, instinctive behaviour is defined as an innate or intuitive impulse, or behaviour that, when triggered, is a reflex or automatic reaction to a situation. The two most commonly recognized forms of instinctive behavior are “flight” and “fight” reactions. Bison evolved as consumers of plant forage or herbivores and therefore do not normally exhibit aggressive or predatory behaviour. Under most circumstances when bison perceive a threat, they will attempt to withdraw or run away (flight response). However, if bison cannot succeed in fleeing or they feel trapped, they will exhibit aggression (fight response).

here are exceptions to these generalizations. Bison strongly express other instinctive behaviours depending on the circumstances. Not surprisingly, these circumstances are often related to reproduction. Bison cows are extremely protective of their calves and bison bulls are commonly aggressive during the breeding season. It should be obvious that producers should avoid handling their bison during the calving and breeding seasons if at all possible. Because of their remarkable physical abilities bison will attempt to escape from a threat either through or over physical barriers that other species would not challenge.

One of the ways to avoid this type of reaction is training bison not to feel threatened when handlers are around them on foot (See Dr. Patterson’s article “Preparation of Bison For Public Sale Venues” in the September 2001 SaskBISONews at and to adopt the 6 R’s of bison handling philosophy using an “Opportunity Based Approach”.

The 6 R’s of bison handling are:

    1. Reduce the size of the group intended for handling
      The number of animals most effectively managed in any particular group is age and sex dependent. Cow-calf pairs and breeding bulls 3 years of age and older are generally most effectively managed as individual units. Weaned calves, yearlings, and bred heifers usually respond best to the handler if they are sorted down to groups of 5 or 3. Three or 5 is almost always better than 2, 4 or 6. This is because with odd numbers there is one individual that does not succeed in pairing up and will therefore be more susceptible to cues about which direction the handler wants the group to go. Avoid getting too many animals in a pen or alleyway. If eye contact cannot be maintained with almost all animals in the working group then the handler has limited ability to influence their range of motion.


    1. Reduce the speed of the group being handling
      Speed is the handler’s greatest enemy. “Speed kills” when handling or sorting bison. Bison need time to think about where they are going. Bison that are moving at high speed have reverted to instinctive behaviour and will challenge barriers in an attempt to force their way through them. Even if the animals at the front of the group perceive a barrier and at the last moment decide to stop, animals moving at high speed directly behind them will force them into the barrier.


    1. Remember the significance of the “ripple effect”
      Bison have a very strict social order. This social order is enforced by aggressive physical contact between individual bison. Bison are also extremely perceptive and subtle changes in posture by a handler will elicit a response by the bison closest to the handler. As this bison moves, adjacent bison react to the movement and start to move which in turn influences bison close to them. This rippling effect can be seen moving through the group being handled. If other team members are initiating a ripple effect somewhere else on the group, these ripple effects will collide and create confusion or in the worst case scenario, chaos. To use the ripple effect to best advantage, stop, and start over when it becomes unproductive. If there is difficulty using the ripple effect, the working group is probably too large.


    1. Release pressure
      Enable the bison to move away from the handler as they advance through the system. Do not put the handlers or bison in a situation where they are being forced them in a particular direction. As soon as they are forced, they perceive that they are going to be trapped against their will and they rapidly revert to an escape mentality. If they cannot escape, aggression is their next option. Pen and alleyway designs need to provide an opportunity for bison to learn that by voluntarily responding to the handler’s presence they can move from unit to unit, relieving handling pressure on themselves.


    1. Retreat
      When bison reach speeds at which they are no longer responding to the presence of the handler or they are crowding into corners and pushing each other, step back. Continue to relieve pressure until they settle down. Give them time to think. If they are stirred up and continue to react negatively when the handler re-engages them, it is likely time for a time-out. The handler should go to the house, have a coffee and not return to the pens until the handler has calmed down and can proceed with a positive, deliberate, patient approach.


  1. Reward
    The handler should have a high quality food reward set out for them in a paddock large enough where all animals in the group are comfortable. When finished working with the bison, leave them in this paddock until it is obvious that the memories of being handled are no longer important. Never turn bison out immediately after being handled. If this is done, their last memory will be of escaping as fast as they could and they will carry this attitude forward into the next handling session. The restraint or squeeze chute should never be set up to release animals directly from the squeeze into their pasture.


Construction of a Component-based Corral and Handling System

When constructing handling facilities it is important to consider which management factors are priorities and will therefore be incorporated into the design. The following system configurations were developed specifically for their compatibility with the philosophy outlined above. This system is not for every producer and success frequently depends on the presence of the handler in the pens at ground level with the bison.

This system described here is “opportunity based”. It functions optimally with bison that have been familiarized with the presence of handlers. Bison that have not previously been handled in this type of system can be trained to react properly in it, but this requires an investment of time and patience by the handlers.

Calves born in an operation with an opportunity based system and philosophy in place grow to adulthood believing that being handled with minimal stress is the rule of thumb. If this system is being implemented correctly it is obvious to the handler that sorting and handling become easier the more times the bison are put through it. Conversely, bison that have had negative experiences in handling systems become increasingly difficult to handle and often resort to aggressive behaviour. Over time this system will demonstrate how effective it is, or where and why the layout and method should be changed.

The system below, properly constructed and implemented, is compatible with handling horned bison. Systems designed to handle bison without horns are often less complicated and rely more on crowding alleys and or crowding tubs. One should remember that although dehorned bison obviously do not gore each other, they still can inflict serious injury on other individuals. Dominant or frightened bison that feel trapped often react by bunting, forcing barriers or running over their counterparts. This is inevitable if they are forced together into small areas with no opportunity to segregate themselves into smaller groups of compatible individuals. I recommend that all producers of horned or dehorned bison consider using opportunity based systems.

Another key factor in opportunity based design is that the animals are habituated to being baited into the staging paddocks rather than being chased in. This ensures that the initial phases of the handling process do not alarm them. Bison that are granted the opportunity to remain relatively calm during the sorting and handling process move at a much slower pace and do not usually resort to aggressive behaviour.

For this purpose it is ideal (but not absolutely necessary) to employ a primary staging pasture limited to 30 to 40 acres and without drinking water. In Figure 1 below this is Pasture 1. If this is not possible some means other than water availability will be needed to bait bison into the first paddock (Paddock A) such as feeding them oats or some other treat. Habituating them to both access to water and to receiving a treat is most effective for 2 reasons.

First, if there is no water in Pasture 1, they must come into Paddock A and move through to Paddock B to gain access to water. They can be trained to wait for the handler at Gate 1 (G1) rather than letting them always have unrestricted access. Larger groups “hold” or stay in Paddocks A and B when offered a treat when they come in for water. Otherwise, bison entering first have had a drink and are heading back out before all the bison intended for holding in Paddocks A and B are caught by closing Gate 1. This “cross traffic” is significantly reduced if access to water is restricted for a reasonable period of time prior to opening Gate 1, making the group more anxious to come in.Remember that bison in Pasture 1 may have all the snow they need for maintenance but given the opportunity will prefer to drink fresh water.

Figure 1

The other reason to habituate them to a treat in Paddocks A and B is that over a period of time these paddocks will become one of their favourite “lounging areas”. Obviously if enough bison are kept in Pasture 1 long enough they will graze it out and supplementary roughage will be needed for them in that pasture. The handler will know that a good job of training the bison has been done when the entire group is lounging in Paddocks A and B with Gate 1 open, and when the handler walks into either paddock they willingly provide the handler with enough time to walk over to Gate 1 and close it before any of them leave.

Why would they permit this? Over time they realize that they are not being locked up just to handle them, but so the handler can have unrestricted access to Pasture 1 to place supplementary feed in it. Believe it or not, this becomes a routine for them. The completion of all routines that work well involves a reward of some kind as the final stage.

Figure 2 illustrates Paddocks C and D. Their importance is not to be underestimated. In an opportunity based system Paddock C is the reason why bison will voluntarily enter Paddock B. There are actually two reasons; they will come to drink, and they will not feel trapped if the gate to Paddock C is open (Gate c). Paddock C must be large enough to give them that comfort level. If bison trained to this system have been held in Paddock A for more than a few hours the leaders will come to Gate b to be let in when the handler enters Paddock B. The handler then stands at Gate b and allows from one to twelve head to enter, depending on the age and sex of those coming to the gate. The herd bulls often come up first for two reasons. They are dominant and are conditioned to being rewarded with oats in Paddock B either as individuals or in small groups. The treat carries a higher value to the bison when fewer head are involved (everyone in the reward group succeeds at getting their reward more easily).

Figure 2


Herd bulls are allowed to enter one at a time and are then moved to another area if the herd is to be sorted. Having the bulls away from the others is very important before components of the herd are allowed into the pens for sorting. If a herd bull will not co-operate with this training program, he is culled from the herd. Bulls that insist on staying with the cow herd cause trouble when groups of animals are sorted into smaller pens. They are dangerous to the handlers and the other bison.

In herds familiar with this type of pen arrangement a mixed age and sex group of up to 70 head can be confined in the dimensions of Paddock A and over time small groups can be allowed into Paddock B. By standing at the appropriate gate into Paddocks C or D, the handler can clear unwanted animals through Paddock C into Paddock D and retain individuals intended for separation from the herd in Paddock B. Selected animals can be moved out of Paddock B through Gate e.

Usually, animals that are the most difficult to sort remain in Paddock A as groups are moved into Paddocks B, C or D. However, once more than half the original group has been successfully sorted quietly and effectively, the remaining animals in Paddock A want to start moving towards Paddock D because they feel that they are being left behind. Remember, by the time sorting is finished, most of the animals that were originally in Paddock A are now in Paddock D. It is important that Paddock D have about the same area as Paddock A for the herd to have enough space to settle and relax.

After bison have become accustomed to moving through these pens, most of the sorting needed to isolate groups of 3 to 5 bison or even yearlings and older individual animals will be done in Paddocks E through H, illustrated in Figure 3. The key to correct use of these pens is to allow no more than approximately 12 adult animals into Pen E from Pen B at one time, typically 6 – 9 adults is best. Gates e, f, g, h, i, j, k and l should initially all be open. Construction of Gates f, g, h, i, j, k and l should be 12 feet wide and when they are swung open into the 10 foot alleyway should connect with the opposite side of the alleyway at an angle. This helps the bison see them better and most importantly, does not create right angle barriers at points in the system where the bison need to change direction quickly. If excessive crowding occurs at these points when bison are moving from pen to pen it is because too many animals are being handled at once or too much pressure is being applied behind them and they are responding by moving away from the handler too quickly.

Figure 3


When given the opportunity to enter Pen E, a group of up to 12 adults will move into Pen E and move towards the north (far) end of the pen. Unless too many animals are allowed into the pen, the handler will have time to close Gates e and f before the bison turn around at the far end and decide they want to come back out the way they came in.

When Gate f is closed the group of bison introduced to Pen E will begin to move through the pens (E, F, G, H) via the open gateways at the end of these pens without any encouragement from the handler. After they have moved through the pens they will start to sort themselves into smaller groups that choose to stay in different pens. Individual animals often move from pen to pen as they scout out the social order being established in each pen. In fairly short order, these small groups will sort themselves as intact groups into separate pens. So, if 12 adults were allowed access to Pens E, F, G, H and were left alone for a while, they would sort themselves into 4 groups of approximately 3 animals in each pen.

Why do they do this? After they have moved through the 4 pens they realize that they are trapped. There is no opportunity to escape beyond the 4 pens. Once they are trapped the competition for the safest space becomes the first priority. The most dominant bison will move toward their choice of position in one of the four pens. The dominant bison will decide how many others they will allow in the group. The rest have to find their own space and so the ripple effect plays out in a positive manner if the bison are allowed to make these choices themselves.

The dimensions of Pens E, F, G and H are very important. Pen E is 38 feet wide while Pens F, G and H are only 30 feet wide. Pen E is wider because it is the first pen the bison enter from Pen B and the increased width provides them a higher level of comfort as they commit to entering the first pen in this series of pens. Pens F, G and H are 30 feet wide because, once bison are familiar with this system, under most circumstances the handler can actually walk slowly down the sides of these pens and the bison in the pen will instinctively move to the far end of the pen. If the handler continues to slowly penetrate the pen the bison will realize that the easiest way to relieve the pressure they experience from the handlers presence is to move up the opposite side, back towards the pen gate. If they are accustomed to the handler, he/she can step out towards the centre of the pen and divide the group as it moves back towards the gate. Some will continue on to the gate and the others will turn back and return to the deep part of the pen.

If the pen is wider than 30 feet they will not draft up and down the sides smoothly. They will simply take the opportunity granted by the width of the pen to run around the handler in circles. If the pen is longer than 115 feet it is too long for a handler to effectively split a group and succeed at moving them up towards the gate and the alleyway with enough gentle momentum that they will not try to turn around and come back to rejoin their group. If the pen is shorter than 110 -115 feet, the pen will not be deep enough for them to feel comfortable in their “safe zone” at the far end of the pen when the handler is splitting the group.

Pen I can be added to the system described above as illustrated in Figure 3. Pen I is simply a rectangular pen that results from constructing a 10 foot alleyway around the inside perimeter of a 128 ft x 50 ft pen erected outside the main alleyway that provides access into Pens E, F, G and H. The result is 2 parallel alleyways sharing a middle divider. The alleyway that frames Pen I enables the handler to control the flow of animals that have been brought out of Pen H into the perimeter alleyway around Pen I. Bison in this perimeter alleyway either move through the portable handling system situated in the alleyway or are loaded out of the corner of the system.

Bison will come out of Pen H into the alleyway junction more efficiently than out of the other pens. This is because they have a longer distance to move to the junction. If the alleyway distance to the junction is shorter, such as it is coming out of Pen G, they sometimes feel trapped in the shorter alleyway and if so, will turn around in the alleyway and return to the pen from which they came.

Figure 4


This entire system is designed so that bison moving through it reduce their speed as they proceed, because it is safer for them to reduce their speed as they change direction. Whenever they change direction, they have the opportunity to advance, therefore they do not perceive that they are heading towards a dead end. They reach a dead end either in the boxes of the chute system or in the trailer into which they are being loading (assuming the appropriate gates are closed behind them). Some handlers believe that bison naturally turn to their left better than their right, or vise versa. In this type of system, once the bison have had some experience, they turn either way equally well.

There is also a perception that bison like to return to where they have come from. This is primarily a natural fear response from movement to somewhere they do not feel secure and they prefer returning to where they felt secure. In this system, once familiar with the flow opportunities, bison understand that if they follow the openings they will eventually get out of the system, which is their ultimate goal. They do not like to be confined. The system enables the handler to sort bison into smaller groups and advance them in stages through various turns, keeping their speed in check. This is truly an “Opportunity Based System”, and if bison are hitting gates or barriers it is almost always the operator’s fault.

Figure 5


After putting bison through the portable handling system illustrated at the bottom of Pen I, the handler has many different options for subsequent movement. To retain some of them, the handler can put them in Pen I or, if there is space available, back into Pens E through H. If the herd requires the retention of more than 100 calves during a working period, construction of additional pens east of Pen H or north of pens E to H is desirable. Figure 5 illustrates just one example of how the gates are reset to move a group of bison from Pen I to Pen E. Animals not retained in E can go into Paddock C and then be moved to any of the other Paddocks (A, B or D) that are suited to the task at hand, or let out into the pastures that connect to these paddocks.

If the herd consists of more than 70 cows, additional paddocks can be linked to paddocks A or D in an inverted L design as in Figure 6. These additional paddocks will enable the handler to gently stage as many bison as required into the overall system and also serve as excellent paddocks for segregation of different age/sex groups or as finishing pens. There is absolutely no need to build a “feedlot” for the final phase of finishing bison bulls or heifers if the system has these L shaped paddocks. As the size of the herd increases, as many additional L shaped paddocks can be joined as the budget and available space allows.

Figure 6


One of the most important features of sorting and handling bison is retaining them for a brief period in a pen or paddock and rewarding them prior to letting them go into a pasture. This is a cooling off period for them. Their final memory of the sorting or processing period is one of being rewarded rather than escaping as fast as they can. If they are allowed to “escape” immediately after whatever was done with them, they will perceive that the faster they go through the process the sooner they will “escape”. This is a very bad habit to instill in bison. NEVER place the squeeze or restraint chute on the perimeter of the system and let bison directly out of the squeeze into a large paddock or pasture. After being released from the squeeze, the handler wants the bison to slow down and start thinking rationally rather than dash headlong for freedom.