Wildlife triangle http://tun.fi/HR.1916
Collection Name
Wildlife triangle (en)
Riistakolmiot (fi)
Viltriangelinventering (sv)
Type of the collection
Monitoring scheme observationsCollection description
Wildlife triangle data, winter census Species-specific annual snow-track counts and average snow-track abundance indices in 50 × 50 km grid cells. The snow-track abundance index for a wildlife triangle (a ~12 km line transect) is calculated as N / (km_counted × snow_days). Here N is the number of snow-tracks crossing the transect line. The denominator stands for counting effort, consisting of the kilometers counted (km_counted) multiplied with the number of days during which tracks have accumulated (snow_days). The snow days are counted from last snowfall, or from the timing of a pre-mapping of snow-tracks, which prevents from recounting the tracks during the actual survey. The presented index for a given species, year and grid cell is calculated as the arithmetic mean index over all triangles, whose point of gravity are within the focal grid cell. In addition to the species-specific average abundance indices, also the number of snow tracks recorded, and the number of triangles counted are reported. The grid is constructed according to the ETRS-TM35FIN -coordinate system and the grid cell locations are given using the lower left corner coordinates (“lon” and “lat”). (en)
Riistakolmioaineisto, talvilaskennat Laji- ja vuosittaiset lumijälkien lukumäärät, sekä keskimääräiset lumijälkiin perustuvat runsausindeksit 50 × 50 km ruudukossa. Lumijälki-indeksi riistakolmiolle (eli noin 12 km pituiselle laskentalinjalle) lasketaan seuraavasti: N / (km_laskettu × lumipäiviä). Tässä N on laskentalinjan ylittävien lumijälkien lukumäärä. Nimittäjässä suluissa on laskentapanostus, joka saadaan lasketun kilometrimäärän (km_laskettu) ja jälkien kertymäpäivien (lumipäiviä) tulona. Lumipäivät lasketaan edellisestä lumisateesta tai ns. esikierrosta, jolloin laskija on kartoittanut vanhat lumijäljet, jotta ei laskisi niitä uudestaan varsinaisessa laskennassa. Tässä esitetty laji-, vuosi- ja ruutukohtainen indeksi on aritmeettinen keskiarvo lumijälki-indekseistä niistä riistakolmioista, joiden painopiste osuu kyseiseen ruutuun. Lajikohtaisten indeksien lisäksi, myös jälkien yhteenlaskettu lukumäärä sekä riistakolmioiden lukumäärä on raportoitu. Ruudukko on muodostettu ETRS-TM35FIN -koordinaattijärjestelmän mukaan ja ruutujen sijainnit on ilmaistu vasemman alakulman koordinaatteina (”lon” ja ”lat”). (fi)
Web address
www.riistakolmiot.fi (fi)
https://www.riistakolmiot.fi/sv/ (sv)
Taxonomic coverage
Siberian flying squirrel (Pteromys volans); http://tun.fi/MX.48243 Muskrat (Ondatra zibethicus); http://tun.fi/MX.48537 Raccoon dog (Nyctereutes procyonoides); http://tun.fi/MX.46564 American mink (Neovison vison); http://tun.fi/MX.47243 European polecat (Mustela putorius); http://tun.fi/MX.47240 White-tailed deer (Odocoileus virginianus); http://tun.fi/MX.47629Temporal coverage
1989–2018Geographic coverage
FinlandCoverage basis
Threatened and invasive mammal species in the winter track counts, excluding the large carnivoresCollection methods
Line-transect census of snow tracks. The transect is ca 12 km long, shaped as an equilateral triangle and located in boreal forest landscape. The survey is done during one day by volunteers, mainly local hunters, skiing or walking along the transect. The survey period starts the 15th January and ends on the 28th February in the southern and central parts of Finland. In the northern parts of Finland (Oulu region and Lapland) the period continues until 15th March.Collection quality
Professional / professionally curated
License
Creative Commons AttributionContact email
andreas.linden@luke.fiData quarantine length (yr.)
3Percentage digitized (approx.)
100Number of specimens
Number of type specimens
Number of all observations
Status of this metadata
satisfactory – could be improvedDate created
13.01.2017 10:02Date edited
24.07.2023 07:53Sensitive observation data have undergone obfuscation including spatial aggregation so that precise locations and other sensitive information is not publicly available. The precise location, place names, dates, names of observers and other information may have been obscured or removed. Read more about sensitive observations.
Data may have a research embargo (usually 2–4 years), during which data may have been hidden or obscured as described above. Data producer-owners may have chosen to permanently obfuscate all or part of their data.
To gain access to non-obscured data, you may make a data request. Non-obscured data is also available to Finnish authorities