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Bear story

The brown bear (Ursus arctos) is a species of the bear family (Ursidae) and, today, the largest wild animal in Europe.

A Bear’s tale

The brown bear (Ursus arctos) is a species of the bear family (Ursidae) and, today, the largest wild animal in Europe.

The brown bear (Ursus arctos) is a species of the bear family (Ursidae) and, today, the largest wild animal in Europe. The bear is a European Protected Species and one that is also protected by a large number of other international conventions, including the Berne Convention and CITES (Convention on International Trade in Endangered Species of Wild Fauna and Flora). The brown bear has considerable spatial requirements, opportunistic omnivorous feeding habits, great mobility and a clear tolerance for the presence of human beings, for which reason it has been classified as a vulnerable species.

In Europe there are around 50 000 bears living across an area of 2.5 million km2. Population densities are changing and depend on the accessibility of food, the number of bears taken from the wild, and growths and falls in population. The brown bear population in Slovenia is part of that which is distributed across the area covered by the Alps, the Dinaric Alps and the Pindaric mountain area. Brown bear is one of the largest populations, estimated at between 2 100 and 2 500 bears. Slovenian bears constitute the most westerly part of the brown bear population in central Europe. The central area of distribution of the brown bear in Slovenia includes the high Karst, an area of dense mixed forest of difficult and complex terrain in the Kočevje and Notranjska regions which extends across the Ljubljana-Kozina motorway to the western edge of the high Karst, i.e. to the Trnovski forest, Hrušica and Nanos, to the eastern edge into the Gorjanci and to the north to the Krimsko-Mokrško mountain range.

In the Strategy for Management of the Brown Bear (Ursus arctos) in Slovenia, which was adopted by the Slovenian government in 2002 in response to the requirement to coordinate protection of the brown bear with human use and activities and to EU demands for the definition of a special protection area, Slovenia was divided into four zones reflecting the different levels of protection in force (Figure 1).

Figure 1: Brown bear areas in Slovenia
Brown bear areas in Slovenia
Source: Brown bear (Ursus arctos) management strategy in Slovenia, 2002

The basis for the management of the bear population is expert knowledge of the biology and ecology of the species, as well as of species numbers and relationship to human beings.

Estimates of brown bear numbers in Slovenia

In most of central and southern Europe, the number of bears fell considerably at the end of the 19th century, and they disappeared completely disappeared from some areas. Today the attitude of people to these wild animals has changed. Therefore, in various parts of Europe, great efforts have been made to preserve bear populations. In 1999 and 2002, ten bears were captured and taken to Italy, to the area of the Adamello Brenta Park. Under an agreement between Slovenia and France, five bears were relocated from Slovenia to the Pyrenees in 2006.

The basis for the management of the bear population is expert knowledge of the biology and ecology of the species (behaviour, feeding characteristics, etc.), as well as of species numbers and relationship to human beings. Two studies were completed at the Environmental Agency of the Republic of Slovenia in 2008 which, using new methods, provided a large amount of basic information about this charismatic species, including an estimate of the bear population in Slovenia.

Previous estimates of the bear population had been based on figures drawn up as a result of observation of bears at permanent counting locations three times a year. According to these estimates, there were between 500 and 700 bears in Slovenia in 2007. The new estimates of population numbers have been obtained using newer methods - i.e. on the basis of age as determined by grinding the teeth of bears taken from the wild and of genetic molecular research.

In the study entitled Analysis of Brown Bears Taken from the Wild in Slovenia 2003-2006 on the Basis of Age Determined by Teeth-Grinding (Jerina and Adamič, 2007), the teeth of 326 bears culled over this period were examined. The analysis was supplemented by data on the age of a further 369 animals taken from the wild before 2003. By examining the age and sex of culled animals, it is possible, on the basis of certain assumptions, to ascertain a number of population characteristics, such as the sex and age composition of the population, its minimum fertility, its abundance, etc. The results of research into population abundance show that there were around 290 bears in 1998, with this number gradually rising to an estimated 370 in 2006. This was followed by another fall to an estimated 320 bears in 2008. In the opinion of researchers, the reason for the growth in the estimated population numbers is high fertility, and partly also the inflow of bears from the Croatian population. The research also points out that, in light of the reduction in population numbers in recent years, the culling of the brown bear must be scaled back accordingly in order to prevent a drop in the population in Slovenia.

A total of 1 057 non-invasive samples (i.e. primarily droppings and some hair samples) were collected for the study entitled Analysis of Bears Taken from the Wild and Genetic-Molecular Research into the Bear Population in Slovenia (Kos et al, 2008). These samples were used to determine the bears' genotype. A total of 354 different bears were identified (159 males, 195 females), which means that there were at least this many bears in Slovenia at the end of 2007. On the basis of these numbers, a method of modelling the capture-marking-recapture for the entire bear population area was used to draw up an estimate of abundance. This estimate, with a 95 % degree of certainty, stood at between 394 and 475 brown bears.

The majority of the bears lived in Javorniki, Snežnik, Menišija, Velika Gora, Goteniška Gora and Mala Gora. Their presence here is expected because of the exceptional crop of beech during the sampling period. The population in the area west of the Ljubljana-Koper motorway was somewhat lower than expected, demonstrating the negative impact of the motorway as a significant demographic barrier.

According to research estimates, the Slovenian part of the brown bear population is in a good state in terms of both numbers and genetic diversity. One statistic does give cause for concern, however: over 80 % of the bears do not reach four years of age, which demonstrates the considerable threats faced by young bears.

The studies mentioned above contain the most reliable results produced so far, constituting the best estimate of the Slovenian bear population. Since the population constantly changes over time, partly as a result of movements across the border with Croatia, it is impossible to arrive at a precise number and it would be erroneous to talk of precision at all.

Figure 2: Location of non-invasive samples collected at the end of 2007
Location of non-invasive samples collected at the end of 2007
Source: Analysis of Bears Taken from the Wild and Genetic-Molecular Research into the Bear Population in Slovenia (Kos et al, 2008) - in Slovene language only

The bear is an opportunistic omnivore, meaning that it eats anything that is available and easily accessible to it at a particular time. Most of the bear's diet is of plant origin.

Bears' diet

The bear is an opportunistic omnivore, meaning that it eats anything that is available and easily accessible to it at a particular time. Most of the bear's diet is of plant origin. The most difficult period is spring, when winter stocks run out and the vegetation season has not yet begun. It is at this time that the bear may attack weakened biungulate game and, occasionally, livestock, particularly sheep and goats. From the beginning of the vegetation season until late autumn, bears enjoy feeding on grass and on the fruits of forest plants (common dogwood, hazel, strawberries, blueberries, blackberries). In the autumn, when they are collecting fat for hibernation, the fruits of forest trees (beech nuts, acorns, chestnuts, hazelnuts, other nuts) and fruit from orchard trees (pears, apples, plums) are an important part of their diet. For bears, protein-rich food includes insects (chiefly ants and their pupae) and carrion. Occasionally, bears will look for food close to human settlements (household waste and other food remains), which can bring them into conflict with human beings.

Part of the Analysis of Bears Taken from the Wild and Genetic-Molecular Research into the Bear Population in Slovenia (Kos et al, 2008) study was devoted to defining the brown bear's diet, with the aim of identifying its most important sources of nutrition. The contents of the digestive tracts of 128 bears taken from the wild between 2006 and 2008 were examined. The remains of food in the stomach and intestines were subjected to precise macroscopic and microscopic examination, and a precise taxonomic identification made (as far as was possible) of food of plant origin. Bears were found to feed most regularly on food of plant origin (forage, forest products, fruit), and less frequently on food of animal or anthropogenic origin (Figure 3).

Food of plant origin is present more or less equally through the whole year, while the frequency of the other two types of food fluctuates considerably (Figure 4). Food of anthropogenic origin is considerably more frequent in the spring and food of animal origin in the summer months.

It is the males that most frequently feed on food of anthropogenic origin, with the females favouring food of plant origin. Food of animal origin is equally represented across the two sexes. It is also noticeable that food of anthropogenic origin is frequently found in bears that have been culled. Research has confirmed the omnivorous and opportunistic nature of the feeding habits of the brown bear, which selects from a wide range of food. Bears adapt fairly quickly to a permanent source of food, whether a feed site or waste in the vicinity of human settlements, and they make regular visits to such areas.

Figure 3: Shares of dry biomass of individual types of food found in the digestive organs of bears
Shares of dry biomass of individual types of food found in the digestive organs of bears
Source: Analysis of Bears Taken from the Wild and Genetic-Molecular Research into the Bear Population in Slovenia (Kos et al, 2008) - in Slovene language only

Figure 4: Frequency of food of plant, animal and anthropogenic origin in bears’ digestive organs at different seasons of the year
Frequency of food of plant, animal and anthropogenic origin in bears’ digestive organs at different seasons of the year
Source: Analysis of Bears Taken from the Wild and Genetic-Molecular Research into the Bear Population in Slovenia (Kos et al, 2008) - in Slovene language only

Several very obvious changes to the environment have had an effect on the biology and behaviour of bears.

Bears and mankind

Human beings can, through the availability of food, affect the movements and activities of bears and thereby indirectly make conflict more likely. However, there are many reasons why more bears are appearing in human settlements. By no means can their appearance and visibility be directly linked to changes to or even a growth in bear numbers, since in recent years and decades there have been several very obvious changes to the environment that have had an effect on the biology and behaviour of bears.

One of the reasons most frequently cited is the reduction in the amount of agricultural land under cultivation and, as a consequence, the rapid overgrowth of previously open areas around settlements, which has allowed bears to move right up to the dwellings. One key factor identified in recent years is the problem of unregulated waste dumps around settlements and the placement of waste containers on the edge of settlements (which are part of the organised system for the collection and removal of household waste). Waste containers are wholly unadapted to use in areas that could be frequented by bears. For these animals, they represent an open food container. A further incontestable fact is the increased pressure exerted by human beings in central forest areas as a result of recreational, tourist and other activities.

In the past, feed sites kept bears in the forest. However, since Slovenia's entry into the EU, these sites are no longer stocked with food of animal origin. Strict veterinary regulations do allow the feeding of wild animals using animal by-products, but the meat of these animals cannot then be used as food for human consumption. Opinions regarding the reintroduction of animal remains dumps (i.e. feed sites supplied with food of animal origin) into Slovenian forests are divided. It should provide a solution to the problem of bears in the vicinity of settlements and, consequently, of possible conflicts between the species. Animal remains dumps are designed to keep bears away from settlements. It is an apparently simple solution which, owing to strict veterinary regulations, is far from cheap and gives no assurance that bears will remain in the forest.

Nor are such assurances provided by the initial results of the monitoring of the movement and behaviour of bears carried out as part of the project Study of the Factors of the Habituation of the Brown Bear to Human Beings Using GPS Telemetry. The main objectives of the research are to study the factors affecting the occurrence of conflicts between bears and human beings, identify the reasons why bears are attracted to the human environment and to ascertain the impact of feed sites on bear movements. Eighteen bears are currently equipped with the latest GPS-GSM collars. These collars can determine a bear's position every hour, 24 hours a day and year-round with the help of a GPS receiver; the coordinates are sent to the specified recipient in the form of a text message via the mobile telephone network. An example of a map of bear movements using GPS collars is shown in Figure 5. In addition, these collars, which have built-in sensors, continually monitor the bear's activity. After one year of operation, the collars automatically fall off.

All the bears equipped with these collars have already visited a village or other human settlement and rummaged through unsuitable waste containers and unregulated waste dumps. There is obviously an abundance of food of anthropogenic origin. A great deal of high-quality data on the movements and activities of bears in Slovenia will be acquired as a result of this research, particularly information on the reasons why a bear might approach a human settlement and display no fear in doing so.

Figure 5: Map of the movements of some bears equipped with collars (12 November 2008)
Map of the movements of some bears equipped with collars (12 November 2008)
Source: Medvedi.si (http://www.medvedi.si)

Bears are responsible for many instances of damage to property and livestock.

Compensation for damage caused to property

During their primarily nocturnal and incessant quest for food, bears can cause damage to property, livestock, in particular sheep and goats, and to apiaries, orchards and crops. Those who suffer damage do receive compensation, but only if they have secured their property against bears. In a four-year period between 2005 and 2008, bears were responsible for 2 419 instances of damage, with 2 276 compensation claims being approved and damages of EUR 590 793 being paid out. Figure 6 shows the number of instances of damage for which compensation payments were approved, and the amount of compensation paid out per year between 2005 and 2008.

Most of the compensation (36 % of the total payment amount) was paid out for damage caused by bears to sheep and goats. This was followed by damage suffered by beekeepers (20 %), agricultural damage (17 %) and damage to fruit-growing (11 %). Every year there are a number of traffic accidents caused by collision with bears (five in 2005 and only two in 2008).

In addition to providing for payment of compensation that matches the full value of the damage caused, the state may also part-finance measures to prevent damage from re-occurring. Every year, on the basis of a public tender, it offers residents of areas in which bears have already caused damage on several occasions 60 % part-financing of the purchase of electric fencing and electric fencing energisers. An average of around EUR 65 000 is spent on this every year.

Interventions in the brown bear population

It sometimes happens that an individual bear will become habituated to human presence since it makes a positive association between that presence and the food it finds in the vicinity of a settlement. Such bears approach settlements and people, thus presenting a danger to human life and health. Although according to some figures only three fatalities have been caused by bear encounters over the last 60 years, this powerful but shy animal still evokes fear.

In exceptional cases, where a bear makes regular visits to the vicinity of a settlement in search of food or causes serious damage to property, suppression may be permitted, i.e. the bear is shot. Of course, not all interventions have an adverse effect on conservation of the population. This must be confirmed by expert opinion, which forms the basis for each instance of exceptional extermination. Usually such exceptional extermination is carried out as a matter of priority in the area surrounding the settlement in which the bear appears.

In addition to the exceptional suppression of individual bears as described above, interventions in the bear population are also made in order to strike a balance between population numbers and environmental capacity. The selective and limited removal of animals from the wild is performed under strict supervision, in limited numbers, if no other satisfactory solutions present themselves and providing such removal does not have an adverse effect on maintaining a favourable state of preservation of populations of bears in their natural habitat.

Conclusion

The protection and management of rare, endangered and charismatic species, such as the bear, is no simple task. It is important that decisions are taken on the basis of scientifically proven and incontestable facts.

The removal of bears from the wild and the payment of compensation for the damage they cause can be only one or part of the measures undertaken to manage the bear population. A number of highly important measures have also been determined in the government strategy and action plan. Informing and educating the groups affected, with the aim of raising awareness regarding the methods used to prevent and eliminate all the factors that attract bears to human presence, is undoubtedly one such key measure.

Figure 6: Number of compensation claims approved and amount of compensation paid (EUR 000), 2005–2008
Number of compensation claims approved and amount of compensation paid (EUR 000), 2005–2008
Source: ODSEV, Environmental Agency of the Republic of Slovenia, 2009

Contacts

Slovenian Environment Agency
Vojkova 1b
SI-1000 Ljubljana, Slovenia
Tel: +386 1 4784 000
gp.arso@gov.si
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