Predators
I am writing this short note based on my experience and that of Polish colleagues. Our experience of the negative impact of predators on the animals that we keep is relatively new, Unfortunately, it is on the increase. I invite FEDFA members to publicize their experiences by contributing to this article, so as to make this body of knowledge available to all.
With the implementation of EU Directive 92/43/EEC (Council Directive on the conservation of natural habitats and of wild fauna and flora – otherwise known as The Habitats Directive), and the creation of the Natura 2000 network across Europe, over 18 % of the EU’s land area and almost 6 % of its marine territory consist of protected areas which offer sanctuary to Europe’s most threatened species. Among the species listed as subject to protection are a number which regard deer as their natural source of protein. Additionally, the protected areas provide relatively secure breeding sites for other, non-protected predators. Bears, wolves, lynxes, wolverines, raccoons and foxes will consume deer meat, although we have no direct experience in Poland (as yet) of wolverines. Howver, it seems likely that depredations due to carnivore attack on deer breeders’ animals are likely to increase into the future.
There is a small population of bears in the eastern part of Poland, particularly in the Bieszczady mountains in the South-East. There have not been any reports of bears breaking through fencing to attack farmed deer, although they are reported to consume fallen carcasses in the wild. For us, at the time of writing bears are not a problem.
Wolverines are supposedly not native to our latitude, although there have been reported sightings in Poland. Lynxes are native, but are few and far between. Thus at present, the situation with regard to lynxes and wolverines is similar to that of bears.
Raccoons, which used to be confined to North America, are now increasingly appearing in Poland. We have them in the forests surrounding our park-farm. We believe that just like foxes, they may pose a danger to newly born fawns, but we have not noticed any incursions to date. The dangers posed by foxes are well known. The fox will climb a 2 metre fence at speed, or dig underneath, if the fence is not buried at least 30cms in the earth. He can suffocate a new born fallow deer and drag it away to his burrow to feed his young. The raccoon may prove to be equally dexterous. Fortunately, neither are on the protected list.
This leaves wolves as the most fearsome adversary faced by the deer breeder. Intelligent, powerful animals, additionally subject to the strictest protection afforded by law. In Poland, the incidence of break-ins to farms and park-farms and livestock depredation is very much on the increase, and deer breeders in areas which have been hitherto free of wolves are now reporting incursions and damage. The wolves have no natural enemies, other than man. Given the favourable conditions for reproduction, it is likely that wolf presence will increase.
Deer breeders in the south east of Poland have reported wolf entry into enclosures either by jumping over or by tunneling under fencing. In all cases, fences which were jumped were below the height recommended for deer keeping (1.8 metres minimum). Extending the fences upwards or topping them with additional wire was effective and stopped ingress by this route. It seems that wolves do not climb fences. However, the attempt to stop ingress under fencing by digging the fence 30 cms into the soil was not entirely successful. A number of instances have been reported where wolves have dug below this 30 cm level and gained entry to enclosed paddocks. Use of multiple strand electric fencing is also not entirely satisfactory, as the wolves will simply start their dig far away enough from the fence, to allow them to dig deep enough so as not to contact the lowest strand of the electric fence..
However, one deer breeder reports successfully stopping wolf ingress by means of tunneling following the installation of a 100cm wide strip of knotted wire netting, laid flat on and pegged to the ground all round the outside of the perimeter of the enclosure and fixed to the fence at the bottom with wire.
A temporary solution, practiced in Russia for wolf containment for purposes of hunting and also used by us at Jelenino this winter, is the installation of fladry fencing. Fladry fencing consists of lengths of brightly coloured tape effectively about 50cms long, tied to a string at intervals of not more than 30 cm. The string is then mounted on stakes at a height of about a metre, about a metre outside of the fencing of the enclosure. The fladry hang down and wave about in the wind, forming an unknown factor which wolves are unable to assess and which therefore they are reluctant to cross. However, Canadian experience is reported as indicating that this should be regarded as only a temporary protection measure (30-60 days), as the wolves soon become familiarized with the “obstacle” and it loses its deterring effect.
For all of us, the most effective barrier between our deer and unwanted visitors is a strong, adequately high fence, dug into the ground to a depth of 30cms at least, although probably 50cms depth would provide better security. At the same time, an adequate height of 1.8-2.0m needs to be provided. At the same time, the external perimeter should be electrified with at least a two strand installation of sufficient caliber (depends on the perimeter length and the intensity of vegetation). If tunneling continues to be a problem, the 100cm “layflat”option can be added without dismantling the existing structure (but at some cost).
Electrifying deterrents: wolves and fladry
Fladry has proved to be an interesting and rather low-tech tool to ward wolves away from domestic livestock in certain conditions. It consists of red flags or pennants attached to a piece of twine or thin rope at regular intervals (about 18 inches or so) and strung around a livestock corral or pen. Like all predator deterrents, it has some limitations.
For one thing, it depends upon the livestock being concentrated in one area — I’m told that it’s tough, and expensive, to string this stuff up around expansive ranges. For another, it loses its effectiveness over time as wolves become accustomed to seeing it. Part of fladry’s success, it seems, is that it’s a new object that causes wolves to become frightened of passing it. Past studies have shown that fladry can be effective in field trials for up to 60 days before wild wovles cross them (Musiani 2003).
In the race of cunning to outwit wolves, some intrepid thinkers came up with the idea of running electric current through fladry to extend its usefulness. Perhaps a little electric shock would ward wolves off for longer, the thinking went. The negative stimulus of electric current works in theory much like the electric-collar on your pooch that tests the boundaries of its yard. (Except, in the case of turbo-fladry, the goal is to keep the wolves out; whereas you want to keep your dog in, but nevermind, you catch my drift…)
In a recent study, some wildlife professionals with Wildlife Services formally tested the effectiveness of electric fladry in both “pen” experiments with captive wolves, and “field” experiments with real pastures that have experienced wolf problems in the past. First, they tested the turbo-fladry and regular fladry, hung 18 inches off the ground, on captive wolves to see if the negative shock stimulus would in fact deter the predators longer from approaching a source of food. They also manipulated the captive wolves hunger levels, to test if hunger was a motivating factor that led them to test both the fladry and the turbo-fladry. The electrified visual barrier was placed around a food source, and motion-sensitive cameras were arranged to fire four shots per second if a wolf approached the barrier. The researchers used gray wolves, Mexican gray wolves and red wolves as their subjects. (When I asked the corresponding author, Stewart Breck, why they used red wolves even though there have been historically very few livestock-red wolf interactions since these animals were reintroduced, he replied that they simply needed more wolf subjects and these were available at the same captive facility.) A road-killed deer, the wolves’ normal food, was placed behind the fladry. (The animals were residents at the Wildlife Science Center in Forest Lake, Minnesota and they were tested within their normal enclosures.) They found that the control groups, which lacked any fladry at all, approached the food source within five minutes, but the wolves who were separated fromt their meal by fladry crossed within one day.
In the first phase of trials, they offered the wolves road-killed deer with no fladry present. All wolves approached their meal within 5 minutes. In the second phase, one group of wolves had fladry placed around an area of their pen where deer carcasses where then placed, and a second group had electrified fladry while the third group remained as a control. (Keep in mind, all three groups were naive to fladry.) Then in the third phase, the wolves that had recieved one form of fladry then recived the other form (so electrified to non-electrified and vice-versa).
Next, for the field experiments, they tested pastures in southwestern and western Montana where there was a history of wolf and livestock interactions. The pastures held native grasses and the surrounding area held a suite of natural ungulates and predators (white-tailed deer, mule deer, elk, moose, grizzly bears, black bears, mountain lions, coyotes and wolves). Livestock included horses, llamas, sheep and cattle. They set fladry and electrified fladry up and kept some pastures free of fladry as controls. Similar to the pen experiments, they put up the two types of fladry then switched them.
Overall, they report that in the pen trials the turbo-fladry performed superior to the non-electrified fladry. Some packs even showed a conditioned memory of the electrified fladry, refusing to cross non-electrified fladry for nine to 14 days. They found more limited results in the field trials, where they relied on the presence or absence of wolf tracks and scat within pastures (and telemetry) to judge whether the fladry and turbo-fladry kept wolves out. They reported that no wolf tracks were found within treatment pastures, though they were found within control pastures (that recived no fladry) and outside of one treatment pasture.
One of their more interesting points was the benefits of turbo-fladry to site-specific “problem areas” where recurrent wolf attacks on livestock have occurred. In these cases, they hypothesize that it could be a highly effective tool. They also noted that it had a possible psychological effect of putting rancher’s minds at ease when they could not be there to physically watch over their animals.
The researchers also addressed the cost issues, stating turbo fladry costs “$2,303 for the first km and $2,032 for each additional km,” and that of their nine project respondents (ranchers), all were in agreement that they would not use it due to the cost alone if they had to pay the full price to install it in pastures ranging from 8 to 65 hectares. However, if another party shared the cost with them, they were much more willing to use it. Although the sample size of ranchers surveyed for this was small (it basically consisted of those who were willing to let the researchers use their land and livestock for the field trials), I doubt the findings would differ widely if a larger, more robust survey were performed. (Pure speculation, just my opinion.) Which is why I think that if the public wants wolves on the landscape, we’re going to have to support helping ranchers adopt some of these non-lethal predator deterrent tools. This is not a popular opinion among many environmentalists, especially out West, who feel that ranchers already benefit from too many subsidies; but the more I’ve studied this, the more I believe that reducing livestock conflicts is a large part of the key to increasing social tolerance for large predators.
A wonderful example of a non-profit working to get non-lethal predator deterrant tools like fladry into the hands of folks that need them is the Mexican Wolf Conservation Fund. This is a small, lean, and efficient NGO that raises money to help reduce conflicts between livestock and Mexican wolves. The fund was started by Patrick Valentino who, at the time, directed the California Wolf Center. (Full disclosure: he helped support my master’s research.) Part of the work this fund does is purchase and set up fladry where Mexican wolf conflicts with livestock are problematic. This year, the Fish and Wildlife Service recognized Patrick as one of 29 “Recovery Champions” nationwide for his work in creating the MWCF. In a press release dated March 18, 2011, the Service wrote: “Patrick was awarded for his work creating a private fund to help conserve the endangered Mexican wolf by minimizing predator-livestock conflicts. Since 2006, the Mexican Wolf Fund has raised more than $300,000 in grants and donations to help fund on-the-ground solutions with ranchers to continue their traditional lifestyles while helping to retain the wildlife heritage of the Southwest.” I personally believe that to help wolves and large predators co-exist with people in a human-altered landscape it’s vital to find solution that not only work scientifically but that are also socially acceptable. Hopefully NGOs like the Mexican Wolf Conservation Fund can help bridge this gap and move wolf recovery forward.