Summary 2013/03

 Summary

Legs as oars, body as a shuttle

Lennart Lennuk introduces a very diverse group of zooplankton: the copepods, which play an important part in the biogeochemical cycle. The copepods are possibly the most numerous multicellulars on Earth. Copepods are like tiny crustaceans, smaller than a rice grain that eat plant plankton and are in turn consumed by fish, whales and even birds. The author introduces the wide diversity of these interesting animals; their diet, habitus, reproduction, distribution, adaption etc. He concludes that there is still a lot to discover about copepods, and the knowledge might prove useful i.e. for understanding the dynamics of fish resources.

 

Estonian Nature enquires

Tõnis Korts explains the attitude of hunters about the draft of the hunting law.

Priit Põllumäe presents the view of forest and land owners about the draft of the hunting law.

 

Tree of the Year: Guelder rose, the shrub of the year

Ott Luuk describes the snowball tree, which does not provide timber, but has a number of valuable qualities, equaling up to „real trees“. The guelder rose is spread all over Estonia and it is best known for its distinctive flowerheads. The berries of guelder rose are bright red and Estonians have considered these as dangerous. However, the berries are, in fact, edible and healthy, and many nations, especially Slavic nations are very fond of them. In addition to the native snowball species, a few other species have been introduced to our gardens and parks.

 

Estonia is a land of boulders

Igor Tuuling and Juho Kirs take a glance at the geology of boulders, characteristic features of Estonia: where did they come from, and how? In Estonia, boulders are mostly defined as crystalline stones from Scandinavia, or glacial erratics. The different types of boulders describe well the movement of former glaciers. Some of these boulders are spread only in specific areas, and are therefore called indicator boulders. Most of the boulders found in Estonia originate from Southern Finland. Based on distribution and numerousness, the boulders of Estonia can be divided into two main groups: first, common and widely distributed boulders and second, rare boulders of little distribution. The authors describe over a dozen crystalline boulder types of Estonia, supplemented with numerous illustrations.

 

Timmase nature protection area

Agu Palo, Urmas Selis and Jaanus Tanilsoo take the reader close to the town of Võru to a nature protection area, where the main protection values include old-growth forests, black stork and eagles. Quite exceptionally the protected area is named after a person – Kalle Timmas – not a toponym. Kalle Timmas was a local who knew the area very well. The protected area was founded in 2004 and comprises some 383 ha. The forests of the area are of different age, creating favourable habitats for many species. Among others, the forests of Timmase form a home for Valdur, a black stork equipped with a satellite transmitter.

 

Interview: The universal tool for brain research

Juhan Javoiš has interviewed Risto Näätänen, a neuroscientist

 

Snow fly in Estonia

Urmas Tartes and Olavi Kurina observe a bug that can live on snow, regardless of the sub-freezing temperatures. In fact, the snow fly is not a fly, but a midge.

 

Old forest roads, winter roads and wetland bridges

Lembitu Tarang, Triin Kusmin and Jürgen Kusmin continue their overview of cultural heritage objects. This time, they turn their glance at ancient traffic roads and the traces of these in the landscape. In old times, there were two general road networks in use: a summer road network and winter road network. Most important winter roads have been marked on maps throughout the history. Roads have been accompanied by taverns: there were about 1200 country taverns in Estonia in the 19th century, with average distance between them 4 km. The article is well equipped with exemplary pictures and stories.

 

Marbled crayfish: a new dangerous invasive crayfish species in Europe

Katrin Kaldre warns against a crayfish species raised in aquarium. The species could easily become used to living in our waterbodies if released to nature. Marbled crayfish or Marmorkrebs poses a threat to our native crayfish population as it reproduces fast and is capable of facultative parthenogenesis, it spreads crayfish plague and can survive in icecold waters.

 

Only one invasive crab species have been found from Estonia so far.

Jaanus Tuusti describes the „success story“ of an invasive crab species, the signal crayfish or Marmorkrebs, in the neighbouring countries and gives advice on how to get rid of the invader. Fortunately, the number of marbled crayfish is probably not very high yet in Estonian waterbodies. In order to keep the species away, it’s important to avoid the transport of the Marmorkrebs from one waterbody to another. The gear should be disinfected to avoid the spread of the crayfish plague.

 

The year of muskoxen

Jaanus Järva shares his experiences of meeting muskoxen in Central Norway. The species have been successfully reintroduced to their former habitats. These large and heavy animals have specific routines and ways of life. The author spent many days with them, through the different seasons, catching photographs and the behavioral characteristics of the muskoxen. The numerous illustrations prove his journey a great success.

 

Environmental monitoring needs principal changes

Toomas Kukk looks at the plans of the Ministry of the Environment to reorganize the current monitoring system: among other changes, the Estonian Meteorological and Hydrological Institute and the Estonian Environment Information Center will be unified. The current environmental monitoring structure is complicated, encompassing 12 subprograms, which are implemented by different institutions without much general coordination. Although huge amount of information is collected every year, it is not easy to find or use this information.  Now there are plans to found a new institution responsible for environmental monitoring as a whole.