Detection & Prevention

3. COST COMPARISON PREDATOR MANAGEMENT METHODS (By Abraham Landman)

There are costs associated with the different methods of predator management. It is preferable necessary to use a combination of methods to be more effective. The effectiveness of only a few methods was scientifically tested, so this is just for background information. There might be some methods not included in this article.

3.1 Assumptions

Every farm is different and unique, with the result that it is very difficult to choose a method, given the size of the farm, topography, number of ewes, specific predator problem etc. It was therefore necessary to make a few assumptions in order to do calculations for comparison.

  • Farm size: 6 000 hectares (based on a Karoo farm).
  • Ewes: 1 000.
  • Herd classification: three herds (dry, lambing ewes and replacement).
  • Control needed for two herds, lambing ewes and replacement.
  • No substitution of any collar was taken into consideration.
  • Labour costs for fitting the collars were taken into account.

3.2 Lethal methods

(a) Chopper hunting

This method can be expensive, especially if only a few predators were shot. It is a method that I think should be used to control abnormal numbers that may arise with time in an area and remove the “tricky” animal effectively. Time of day is important, since it is more effective to i.e. fly three hours early in the morning and an hour or two at sunset. Your “tricky” predator can be effectively removed, large areas can be covered and difficult terrain can be managed.

(b) Night hunting

The calculation involves the hiring of a professional hunter at R500 per night and R600 per predator killed, for four nights in a month, for four months in a year, which means 16 nights in a year. If you want to hunt yourself, the initial cost will be about R11 000 for the equipment, plus your fuel and ammunition.

Night hunting is very effective to reduce numbers quickly. It is specie-specific and you can act immediately if there is a problem. Please use professional people, because it will be better to leave the predator if you are not doing it right. It will only make the predators more shy.

(c) Hunting dogs

The initial cost is calculated for three dogs at R7 500 each and one dog at R5 000 to buy, as well as the construction of kennels. The maintenance cost for a year consists of dog food, veterinary inspections and fuel expenses. It may be that this method is very expensive compared to the otter methods, but the team does not have to hunt on only one farm and can be used on other farms in the area to decrease the cost per unit.

(d) Gin traps

This method is probably one of the most effective and a cheaper lethal method. Gin traps cost R200 per unit and usually last very long. If current farm staff do the work, it is not necessary to introduce an additional hunter. If so, the minimum wage must be taken into account for the hunter.

It is important to emphasise the fact that traps are very controversial, so it is vital that traps must be regularly serviced, calibrated to + 1,7kg and if set, monitored regularly not to trap innocent animals. Monitor traps daily! Do not set traps underneath a fence or in foot paths. Cost calculation includes fuel and wages for trap monitoring.

3.3 Non-lethal methods

(a) Celmax collars

The purchase price is R5 500 per collar and one collar is required for a herd. Once the herd starts acting abnormally, during theft or a predator attack, the Celmax alarm calls the farmer’s cellphone to warn him. The farmer must act and find out what is wrong. The collar has a twelve-month warranty and a battery that lasts approximately eight weeks. A charger is included. The collar is sometimes not very effective against lynx, which often catches the sheep before it can start running.

(b) E-shepherd collars

The cost is R770 per unit with one collar needed per ten sheep. Batteries last nine to twelve, with maintenance R500 per year.

The E-shepherd device is held with a belt around the animal’s neck. The electronic device will be activated when an attack occurs on the sheep. Such an attack triggers a sound alarm emitted by the device. The device also has two lights, which has a stroboscopic effect when the system is activated.

(c) King collar

The calculation is made at R9 for every lamb in the flock, according to the recommendation. It will be possible to fit only collars for a percentage of the flock to make it cheaper. It is important with the king collar, bells and other collar methods, where the predator gets used to the method, to change the methods every three to four weeks.

(d) Dead-stop collar

This collar of steel will last for a lifetime. Different sizes for large and small sheep are available at ±R29 per collar. The calculation is done for only 1 000 lambs, from 1 000 ewes.

(e) Owner's choice collar

The initial cost is R17 per collar and calculations are made for a collar for each lamb on the farm.

(f) Bells (Protect-a-lamb)

Bells are calculated for each lamb on the farm at R13 per bell. As with the other collar methods, it certainly is possible to put bells on for only a percentage of the lambs. A lot of the different methods work only for a while until the predator adapts or gets used to its effects. Thus, use more than one method alternatively.

(g) Modern Shepherd

The cost is R8 000 per unit, and two units were taken into account. More is necessary, but the focus is on the lambing ewes. A bottle of scent should be replaced monthly. The Shepherd works on the sensitive senses of predators in order to keep them away from livestock. These are:

  • Sound: The Shepherd generates an ultra-high frequency sound every 50 seconds that is barely audible to humans and sheep, but extremely irritating to predators. If predators come within a 1km range of the shepherd, it causes them discomfort and even pain.
  • Smell and taste: The built-in computer program controls the release of specially formulated aromatic fragrance ingredients irritating the predator’s smell and taste senses. Every 14 minutes during the night it releases a fine mist of fragrance that is constantly present in the camp.

(h) Fauna track

The system is marketed for stock theft, but water levels of dams can also be monitored. Use cellphone signals. The system includes a control station and diverts station, which cost R11 200. A licence fee of R3 000 is payable annually, and rent for two GPS tags and one RF tag per ten ewes.

(i) Agri-Alert

A neck collar with a combination of GPS and activity sensors is included. Camp boundaries or area limits can be set in advance. The neck collar also activates your phone by SMS if there is disorder. Collars are replaced every two years free of charge.

(j) Hotgroup

The system has several functions such as behaviour monitoring, pasture utilisation and predation management. One collar is used per 200 sheep and it costs R7 800. An amount of R1 888 is used for airtime per year. The alarms are based on science of imitation and are activated if animals act abnormal.

(k) Electric fences

The calculation of the electric fences was done based on a 6 000ha farm boundary fence. (If only the camps for lambing were fenced off with electric fences it could be cheaper, but depending on the farm size the fencing of only part of the farm can be detrimental to the grazing programme. Camps sometimes need rest, but, because of fencing, the producer is forced to let ewes lamb in the same camp every year.)

An electrical wire near the ground and a top line cost about R2 715 per kilometre (jackal trial separately at about R22 000 per kilometre).

Additional to the construction of the fences, it must be controlled to ensure that it’s working and to mend potential holes.

(l) FM radio

A device that costs R1 200 is set at certain times in the night to switch onto a radio station, alternating with light and sounds.

(m) Lights

Lights with a sun panel are mounted on fences to change the scenery slightly.

(n) Alpacas

Alpacas, at a cost of R6 500 each, can graze with sheep. They are believed to be good deterrents for predators, like donkeys, and are not scared of predators. Your maintenance costs will be your opportunity to make up for the cost of sheep that you keep less to make space for Alpacas.

(o) Anatolian dogs

The cost is R2 500 per dog with a training cost of R1 500 per dog for one year. The dogs work well, but it takes a lot of time to teach them and it is difficult to move herds between camps. See the article on Anatolian dogs later in the book. Maintenance costs include dog food and fuel to visit the flock once every two weeks.

The variety of methods is an indication that there is not a specific method that works alone, and that each farm’s circumstances are different. Methods with cellphone signals in certain remote locations are not as effective. It is very important that most of the methods (especially non-lethal) must be used in combination and they must be mingled every three to four weeks to prevent the predator from getting used to it. Evaluate your situation and plan carefully. Know your farm! Use a combination of non-lethal and lethal methods respectively to protect your lambs against an unexpected attack by a predator and to control predator numbers. The goal should not be to eradicate, but to manage.

In the wild, the Alpha predator like the lion controlled the smaller predator numbers, but because of fencing and more people spread across Africa, we know that “nature” is only in “balance” in nature reserves. It is therefore necessary for the management of excessive numbers. The biggest problem is neighbours who don’t support each other in the management of predators. It must be a joint effort and should be approached with responsibility.

Figure 1: Total cost in first year

Figure 1 Cost

Figure 1 shows the total cost per method for the first year, i.e. this includes the initial cost to obtain the method plus the cost of applying the method. For example, helicopter hunting has no initial cost as this is usually done by a contractor. The method’s costs only include operational costs such as fuel and rand per predators. Your gin trap includes the initial cost to buy it, plus your labour to set the trap and fuel for daily visits when the trap is set. The lethal methods (red) are important in the management of predator numbers that are out of balance in nature mainly because of the absence of their natural enemies.

The non-lethal methods are mostly a deterrent at their best. The electric fence is very expensive, but that is because it is only calculated for the first year. The method is a long-term investment and when the initial cost is divided over the number of years it will last, then the cost will be much lower per year. Hounds look very expensive, but if they can be used effectively on more farms, then the costs will come down.

Night hunting refers to the hiring of a professional night hunter and not the use of your own equipment, it’s very selective and is a method that can be used to respond quickly to losses. The human guard is a shepherd for the sheep like in the old days, but the effectiveness is unknown because the pen of sheep is not recommended in most parts of the country because it includes soil erosion, is labour-intensive and animal production can be affected negatively and cause wool contamination. Human guards are extremely expensive compared to other methods because the costs will be repeated every year and therefore cannot be spread over time.

Figure 2: Initial cost

Figure 2: Initial cost

The E-shepherd collars and Agri-alert seem to be the only methods that fall outside the average price range of these systems. Traps have the lowest initial cost, so it is the cheapest to buy. FM radio and lights must always be used in combination with other methods that make it more expensive than traps and only a deterrent against a trap that can manage a damage-causing animal. Figure 2 though, just shows the cost to “get” the method available.

Figure 3: Cost per ewe

Figure 3 Cost

Figure 3 shows the total costs per ewe if the initial cost is divided over one, three or five years. In other words, capital expenditure to buy the method is divided over the period used, while the annual cost of applying the method/use each year is taken into account. Only the initial cost is divided over the years. The methods that have not declined over time had no initial cost. It is clear from Figure 3 that the expenses for lethal methods are more or less the same or less than most of the non-lethal methods. There are a number of non-lethal methods that work out cheaper.

3.4 Recommendation

Use non-lethal methods, but remember to do it sparingly and with constant changing, as the predators get used to it in three to four weeks. It will therefore be necessary to acquire more than one method. Lethal methods are needed to remove excessive numbers of problem predators, as the non-lethal methods mainly swift the problem to the neighbour for a while. Furthermore, it is essential to use the methods responsible and keep the name of our agriculture industry high.

Table 1: Costs: Lethal methods

                Table 1 Cost

Table 2: Cost of non-lethal methods

                Table 2 a Cost

                Table 2 b Cost

                Table 2 c Cost