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There is still almost half a year left to write your stories of encounters with the Animal of the Year, the wild boar. Boars have not always been living in Estonia as the article below by paleozoologist Lembi Lõugas shows. Boars have migrated to Estonia several times, disappearing during difficult periods, then returning again. Most recently the boar started to dig its hooves more firmly into the Estonian soil as late as in the 1930s. Journal  Loodusesõber invites stories about personal encounters as well as tales heard from grandparents. Tales from the manor house period are also welcome – from a time when the tracks of a strange large animal were observed in the forests but of whom nobody knew anything...

 

Stories of encounters with boars can be sent to the address:

helen@loodusajakiri.ee.

 

Male boar

 

 

After the Ice Age the wild boar has arrived to live in Estonia several times, then disappeared. Where did it go in the meantime and why?

 

In the second issue of Loodusesõber in 2015 Peep Männil wrote about the present abundance of wild boars in Estonia. The numerical indicators for wild boars would certainly be much lower if humans were not assisting the increase by their activities. The species has for instance not survived earlier cold periods without human aid. Perhaps it is worthwhile to consider a more distant past than the last couple of centuries to understand what has happened earlier to this interesting animal that now has earned the title of ”Animal of the Year”.

 

The boar is considered to be a native species of Central Europe, the Mediterranean area, North Africa and most of Asia. In Europe the distribution of the wild boar has been historically linked  to the spread of broad-leaf deciduous forests, but quite as a clear borderline cannot be drawn between deciduous and coniferous forests, so does the habitat of wild boar not end at that theoretical borderline. The territory of Estonia has for thousands of years been an intermediary zone between these two forest types, or stating it briefly, we have mainly mixed forests. The climate has also played its tricks here from time to time, changing the forest types and their characteristic animal species, in kinds or numbers. Much depends on the more or less good adaptability of one or the other species. Since the wild boar manages very well also in the mixed forest belt as long as there is acceptable food in the humus layer of the deciduous trees and spruce forests for instance offer good shelter in winter, there are not many obstacles to its living here. On the other hand, when living at the northern limit of the population’s distribution area there are not many survival options when the climate becomes colder and particularly with increasing amounts of snow.

 

Among the first arrivals

 

The wild boar was part of the Estonian fauna already immediately after the Ice Age. Species of the Arctic steppes, such as reindeer and mammoths, that passed through here in the late Ice Age period disappeared from here and the gradually more forested areas were inhabited with the animals that we largely meet here even today. The presently earliest known human settlement in Estonia, in Pulli at the Pärnu river, has given us among other things the oldest finds of boar bones here (nearly 10 500 to 10 700 years old). They are not very numerous but the species must have been present in ”huntable numbers”, i e there must have been sufficiently many boars in nature for Stone Age man to know how to hunt them and to want to do so. Considering all kinds of losses associated with the cutting up, usage, preparation, deterioration in soil and so on, a sufficiently large amount of bones have been preserved until today. The habitation period of Polli is regarded as significantly cooler than the average today, and the sparse forests were predominantly habitats of pines and birches. Referring to the finds of wild boars and also among others roe deer we have to conclude that in that period probably this river-side area offered more favourable climatic conditions to these animals and following this also to the humans who did not hesitate to choose the more northerly cooler areas for living in.

 

Stone Age bone finds

 

Possibly there were more colder periods in those distant millennia when the boar disappeared from Estonian territory but from nearly all Estonian stone age (i e up to 3800 years ago) human settlements boar bones have been found among others. It may be stated with confidence that the boar was represented here most numerously in the warmer period (about 8000-5000 years ago) after the Ice Age. In our areas then a Mediterranean climate reigned rather than today’s year-round  poor skiing weather.  In the forests of that period broad-leaf trees dominated and several animal species with a southerly habitat arrived here (among others red deer). There has been no better period for the increase of the boar population (without human assistance) than that span which includes the so-called climatic optimum period, and also the period following it when the forests with plenty of oaks offered a rich source of food for boars.

 

Mixed domestic pig and boar bones

 

To estimate the respective parts in the life of ancient man of the domestic pig that arrived in the Estonian area towards the end of the Stone Age (Late Neolithic) and the wild boar has turned out to be complicated. . Since the evidence from those times has been preserved as bone finds in the ancient settlements then how to distinguish the skeleton parts of basically the same animal species, although they lived and developed in different conditions. Size is only a conventional characteristic here because the problems arise precisely at differentiating between the ”bigger domestic pig” and ”smaller boar”, all the more because the late Neolithic domestic pigs were probably free-running and in the case of many bone finds they have been thought to originate from offspring from relations between domestic pig and boar. On the Baltic Sea islands, particularly on Gotland and Oesel, late Neolithic bones of such semi-domesticated pigs have been found. It has remained to some extent unclear whether we have to do with domestic pigs gone feral again, domesticated boars or instead cross-breeds.

 

Boars become rare in Bronze and Iron Age

 

Be it as it may with the late Neolithic period but the Bronze age that followed (ca 3800–2500 years ago) and younger eras as well were even more complex regarding pigs. Although the greater part of the Bronze age pig bones from our ancient settlements without doubt already morphologically or exteriorly  belong to domesticated pigs, solitary boar bones are doubtless present in this find group. But again there is a great number bone remains that fall into a so to say middle group and it cannot be said with certainty to which pig form they belong. Looking at the overall picture in Estonian as well as Latvian Bronze age and the following Iron Age settlements the impression is that the boar in that period was rather a rarity than widely occurring. In the Bronze Age there were also several brifer cooling periods which paleoclimatic data as well as the great number of seal bones in Saaremaa’s late bronze Age settlements show. The abundance of seals certainly points to suitable ice conditions in winters which would favour their reproduction on ice. Cold winters however will not favour the number of boars.

 

A new wave in late Iron Age

 

Starting from the finds of boar bones in the ancient settlements and the forts of late Iron Age the increase in the period 1200-1700 years ago can be noted. During this period the climate here was somewhat milder which may have suited boars better. Winters were not very harsh and rich in snow. The shift of the northern limit of the European bison’s distribution at least into the southern parts of Estonia points towards this. The significant increase in the numbers of boars as well as bisons is particularly clear in the materials from the Latvian settlements of that period, but in Estonia too it is noteworthy.

 

„Little Ice Age” sent boars out of Estonia

 

Unfortunately the period with favourable conditions for multiplying did not last long. Around the beginning of the 14th century a significant cooling started, called ”Little Ice Age” and it was anything but favourable for the numbers of clove-bearing animals. 3-4 major cold periods occurred during the interval, alternating with short warmer periods. The coldest periods occurred in the 17th-18th century when even the river Thames froze in the winters. Evidently the occurrence of boars i a on Estonian territory that was already mentioned in written records was in many respects linked to these warm periods, and the disappearance of the boars in turn with the cooling intervals. The major cooling off in the 17th–18th century proved to be fatal for boars not only in Estonia but also in the Latvian, Lithuanian and possibly even more southerly areas of the boars. They disappeared - to return again.

 

Back in Estonia in the 1930s

 

They returned again around the 1930s. The cold winters in the beginning of the 1940s slowed down the spread but only briefly. Whether to count the boar as an indigenous species or a new arrival is for everyone to decide on their own according to their views and  relations to the boars. It has been present here in periods over the times, although after the absences it has been new animals that have arrived: not  the same population that has scuttled now southwards, now again northwards. It seems however that the boar finally has arrived to stay now; never mind that it can live here in the North for longer periods only with the assistance of humans.

 

The article, with lavish illustrations, will be published in the magazine Loodusesõber, available in June/July 2015

 

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