Wildtier-Informationssystem Der Länder Deutschlands Results 2006
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Wildtier-Informationssystem der Länder Deutschlands Results 2006 An initiative of the German Hunting Association (Deutscher Jagdschutz-Verband e.V.) and its regional hunting associations What is WILD? The Wildtier-Informationssystem der Länder Deutschlands (WILD) is a nation-wide monitoring programme which collects data on the sightings, frequency and popu- lations of wild animals. WILD is a project of the Deutschen Jagdschutz-Verband (German Hunting Association, in short DJV) and its regional hunting associations, and, since 2001 has been a permanent part of the ecological environment study. The most important goal is to develop strategies for conservation and sustainable use of wild animals. Data collection in WILD is based on wild animal numbers in selected areas, the so-called reference areas, as well as on population estimates in as many of Germany‘s hunting grounds as possible. District owners support the project on a voluntary basis, thereby significantly contributing to the conservation of wildlife. Additional data on brown hare, red fox, badger, carrion crow and partridge, as well as on factors which could affect their population density, is collected in the reference areas (e.g. landscape structure, land use and climate). In 2006, data on sightings and, in some cases, frequency of 24 other species was also collected nation-wide for the first time (area assessment, AA). Over 30,000 game tenants took part, corresponding to some 50% of districts nation-wide. Geographical regions of Germany: 1 - Northwest German Lowlands 2 - Northeast German Lowlands The results of the annual data collections are published in detail in the WILD 3 - West German Low Mountain Range annual reports (www.jagdnetz.de); this brochure gives a summarised overview of 4 - East German Low Mountain Range 5 - Southwest German Low Mountain Range the 2006 results. 6 - Alpine Foothills Brown hare Since autumn 2001, brown hare populations are recorded in spring and autumn every year in the reference areas through spotlight censuses. Density [Individuals/100 ha investigated area] 100 Data from 706 reference areas (spring)/631 areas (autumn) from 15 states were 80 incorporated in the calculation of brown hare populations in 2006. The calculations of net growth rates are based on 583 reference areas which took part in both the 60 spring and autumn counts. The developments of the 2002-2006 spring populations are shown through three assessments each using a different data basis. 40 The mean spring populations of brown hares fluctuated between 12 and 38 hares/ 100 ha in the western German states, and between 2 and 7 hares/100 ha in 20 the eastern German states. The mean autumn populations varied between Spring 10 and 53 (western Germany) or once again between 2 and 7 hares/100 ha (eastern 0 Autumn N = 126 124 170 172 133 116 50 52 163 111 64 56 NO-Lowland W-Low mountains SW-Low mountains Germany). The spreads range from below one to almost 145 hares/100 ha (spring) or NW-Lowland O-Low mountains Alpine foothills 168 hares/100 ha (autumn). Comparison of spring and fall brown hare population densities The average net growth rates for brown hare populations in Germany were around between the geographical regions 3% in 2006, with the summer growths since 2003 (20%) continuing to drop. of Germany in 2006 The highest mean net growth rates were recorded in Lower Saxony, North Rhine- Westphalia, Hamburg and Bremen. Brown Hare (Lepus europaeus) The brown hare originally inhabited the steppe, but has adapted very well to the contemporary cultivated land- scape. It is found in almost all parts of Germany, mainly in wide open spaces, but also in forests. The brown hare is clearly larger and thinner than the rabbit and has longer ears, which have a black tip. Its fur is yellow-brown with a reddish tinge. The brown hare’s diet is purely vegetarian and very varied, depend- ing on the choice. In low population densities, it lives individually or in pairs, and for higher densities, there is a tendency to form groups. There is a lot of social contact between the group members and, in early spring, larger gatherings, which are distin- guished by the fierce courtship fights Spring population densities of the brown hare in the reference areas in Germany (so called mating time). No dens are in 2006 dug, but rather, superficial hollows (seats) are used for protection. Ges- tation time is 42 days, and 2 or 3 lev- The spring density of brown hares in Germany increased from 10 to 15 hares/ erets are born 3 to 4 times over the 100 ha between 2002 and 2006 based on all participating reference areas. Taking summer. Weather conditions, natural enemies and illnesses mean up to into account the addition or withdrawal of assessment areas, it must be assumed 80% of leverets often do not survive. that this population growth of 5 hares/100 ha overestimates the actual situation. After about 4 weeks, the leverets are This is because, when analysing the population development in the 243 areas independent, and are sexually ma- ture at 6-8 months. which continuously conducted spring censuses from 2002 to 2006, a rise in popu- The brown hare comes under the lation densities was also recorded, which turned out to be much more moderate. hunting right and is only hunted on The overall increase in hare density is therefore more likely to be around 30%. one day in November/December in most field districts during hunting The assessment of population growth in the areas which had conducted censuses season. in two consecutive springs showed a similarly positive trend. The increase in the brown hare population between 2002 and 2006 is essentially a result of the high net growth rate of 2003 (“the summer of the century”), which was clearly above the values for the other years. Red Fox 2006 saw the fourth nation-wide uniform data collection on fox population densities, where data from 344 hunting districts (almost 266 200 ha) was assessed. With a mean value of almost 0.3 litters/100 ha across all hunting districts, the litter density achieved the lowest value nation-wide since the start of data collection in WILD. The mean spring population derived from the litter density was 0.7 foxes/100 ha, and the mean minimum summer density 1.9 foxes/100 ha. The average litter size for 2006 was 4.2 pups/litter - below that of the previous year. Differences were Red Fox observed between the individual regional landscapes, with clearly higher litter sizes (Vulpes vulpes) in the lowlands of north-western Germany. For the first time, den location data was assessed in conjunction with the forms of land use existing in the hunting district. According to this, the recorded hunting The red fox is the most common and district areas were divided into 13% forest, 86% agricultural and 1% other areas. most widespread game species in The dens are often (38%) found disproportionately in the forest. Germany. It inhabits both field and forest districts and can adapt excel- lently to settled areas. In regions with lower densities, adult foxes live largely as loners outside mating sea- son. In higher densities, it lives in hi- erarchically structured family groups comprising a male, a vixen and 1-4 other vixens (the daughters of the dominant vixen). During the day, it remains hidden in the forest, bushes, thick groves or grain fields. Self-dug dens are generally structured very simply; mother dens are somewhat more complex. Badgers’ burrows are eagerly taken over and often co-in- habited. The fox’s diet is very diverse, with its main prey being mice. Mating season is in January and February, and gestation time is 50-58 days. 4-8 pups are normally born, which remain at and in the den for 1 ½ to 2 months, and become sex- ually mature at around 10 months. The red foxes is subjected to the hunting right. In most German states, the older foxes, at the least, have a close season. Den densities of the red fox in the reference areas in 2006 Badger Data on badger sightings in Germany was collected as part of the area assess- ment. According to this, 75% of hunting districts had badger sightings. The den and litter mapping for badgers took place parallel to the red fox data collection. The litter densities recorded between 2003 and 2006 remained almost unchanged with 0.07 litters/100 ha in 2006. Based on the den and litter mapping, a minimum spring density of 0.2 badgers/100 ha was recorded across all hunting districts. Assuming a litter size of 3 pups/litter, this results in a minimum summer density of 0.4 badgers/100 ha. Badger The badger den location was also assessed for the first time in conjunction with the (Meles meles) natural environment. The land usage of the hunting districts taken into account in the assessment is broken down as follows: 16% forest, 83% agricultural areas, 1% The badger belongs to the marten other areas. Conversely, a total of 57% of dens were located in the forest. Just 3% family and is easy to spot with its of dens were located in pure open space, demonstrating the significant connection striking colouring. It is predominantly to forests and well-covered structures. active at twilight and night, and lives rather socially in family groups. Up to 3 families live together in one den, which is very deep with many branch- es and is constantly expanded. Badg- ers are omnivores and their main diet consists of numerous small animals. The proportion of plant consumption is higher than for other game.