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I studied the rare and threatened lesser white-fronted goose (Anser erythropus), abbreviated LWfG in 1989–1996 in sub-arctic Finnish Lapland (I). The studied subpopulation consisted of 2–15 breeding pairs annually. A total of 30 broods were observed with an average of 2.9 goslings per brood. The 1st year survival of tagged 10 geese was low. Satellite locations, recoveries and re-sightings were received from NW Russia, Kazakhstan and the Azov Sea area. Cold spells had a negative, and the sum of effective temperatures by 5 July a positive influence on reproduction. Habitat selection (II) was studied in the same area. LWfG preferred the vicinity of water, flat close-range landscape, low forest height and intermediate relative altitudes. LWfG aggregated in the vicinity of conspecifics within the preferred habitats. The averaged RSF model assigned observation and random points correctly with 83.4% success. Locations of historical observations of LWfG matched the predicted distribution of breeding sites. (III) Spring migration patterns on the Bothnian Bay coast of LWfG were examined in 1907–1916 and 1949–2014 and the taiga bean goose (Anser fabalis fabalis) in 1975–2014. Arrival of the short-distance migrant A. fabalis advanced more and earlier than the long-distance migrant A. erythropus, 10.9 days since late 1980’s vs. 5.3 days since the beginning of the 2000’s. In the LWfG, the best model for explaining variation in timing included global and local temperatures, in A. fabalis global and local temperatures and winter NAO. Increasing global temperatures seem to explain trends in both. In the spring staging places of the Bothnian Bay almost all dietary items of the LWfG were Monocotyledons, mostly grasses growing in extensive sea-shore meadows (IV). Only Phragmites, Festuca and possibly Triglochin palustris were preferred. Lesser White-fronts preferred extensive natural meadows. Mowing and grazing benefit the restoration of habitats. Genetic structuring of the LWfG was examined in its whole distribution area from Fennoscandia to East Asia (V). A fragment of the control region of mtDNA was sequenced from 110 individuals. 15 mtDNA haplotypes were assigned to two mtDNA lineages. Molecular variance showed significant structuring among populations: the main western in north-western Russia – Central Siberia, the main eastern in East Asia and the Nordic one, which earns a status as an independent management unit. Tiivistelmä Tutkin uhanalaisen kiljuhanhen (Anser erythropus) pientä, 2–15 parin pesimäpopulaatiota vuosina 1989–1996 Tunturi-Lapissa (I). Yhteensä näimme 30 poikuetta, joissa oli keskimäärin 2,9 poikasta. Rengastettujen ja lähettimillä varustettujen kiljuhanhien ensimmäisen vuoden säilyvyys oli alhainen kertoen kovasta metsästyspaineesta muuttomatkoilla. Paikannuksia ja löytöjä saatiin Luoteis-Venäjältä, Kazakstanista ja Asovanmereltä. Takatalvilla oli negatiivinen ja alkukesän tehoisalla lämpösummalla positiivinen vaikutus lisääntymiseen. Kiljuhanhet suosivat veden läheisyyttä, laakeaa lähimaastoa, matalaa pensasmaista koivikkoa ja lieviä suhteellisia korkeuseroja sekä lajin toisten parien läheisyyttä (II). Resurssienvalintamallin havainto- ja satunnaispisteet osuivat kohdalleen 83,4 %:n todennäköisyydellä ja historialliset havainnot hyvin mallin ennustamille pesimäalueille. Kevätmuuttoa tutkittiin Perämerellä 1907–1916 ja 1949–2014 kilju- ja 1975–2014 taigametsähanhella (Anser fabalis fabalis) (III). Lyhyenmatkan-muuttaja metsähanhen muutto aikaistui enemmän ja varhaisemmin kuin pitemmän matkan muuttaja kiljuhanhen, 10,9 vuorokautta 1980-luvun lopun jälkeen, vs. 5,3 päivää 2000-luvun alun jälkeen. Kiljuhanhella parhaassa vaihtelun selittävässä mallissa olivat globaalit ja paikalliset lämpötilat, metsähanhella myös talven NAO. Maapallon kohoavat lämpötilat selittävät aikaistumisen molemmilla. Kiljuhanhen Perämeren kevätlevähdyspaikkojen ravinto (IV) koostui yksisirkkaisista, etupäässä heinistä. Kiljuhanhi suosi järviruokoa, punanataa ja ehkä paljon harvinaisempaa hentosuolaketta. Kiljuhanhi ei ole ravintospesialisti, mutta suosii avarimpia rantaniittyjä. Niitto ja laidunnus ylläpitävät elinympäristöä. Maailmankannan geneettistä rakennetta (V) tutkittiin Fennoskandiasta Itä-Aasiaan. Mitokondrio-DNA:n kontrollialueen pätkä sekvensoitiin 110 yksilöstä. 15 haplotyyppiä jakaantuivat kahteen päälinjaan. Molekyylivarianssissa läntisen Venäjän – Keski-Siperian ja Itä-Aasian populaation ero oli merkitsevä. Pohjoismainen populaatio luokiteltiin omaksi luonnonsuojelubiologiseksi yksikökseen.

Moose ( L.) browsing was studied in young Scots pine ( L.) stands mixed with deciduous trees in high-density winter ranges. The proportional use of twig biomass decreased as the availability increased. The total as well as proportional biomass consumption were higher on the moist than on the dry type of forest. The per tree consumption of pine was higher on the moist type, where the availability of pine was lower. Deciduous trees were more consumed on the moist type, where their availability was relatively high. The consumption of pine saplings increased as the availability of birch increased. Pine stem breakages were most numerous when birch occurred as overgrowth above pine and at high birch densities. The availability of other deciduous tree species did not correlate with browsing intensity of Scots pine. Moose browsing had seriously inhibited the development of Scots pines in 6% of the stands, over 60% of available biomass having been removed. Rowan and aspen were commonly over-browsed and their height growth was inhibited, which occurred rarely by birch. There was no difference in the proportion of young stands in forest areas with high and low moose density. A high proportion of peatland forests was found to indicate relatively good feeding habitats in the high-density areas.Alces alcesPinus sylvestris

Two-year-old containerized Scots pine ( L.) seedlings, raised under different fertilization and watering regimes, were subjected to feeding preference tests with pine weevils ( L.) in a bioassay. In the tests carried out with pairs of seedlings, the weevil preferred water-stressed seedlings to well-watered ones. In the case of well-watered seedlings, the weevil caused significantly more damage to NPK-fertilized seedlings than those given pure PK fertilization, or no fertilization at all. It is apparent that PK fertilization reduces, and water stress increases seedling susceptibility to weevil damage. The results support findings from field trials that water stress (planting shock) predisposes seedlings to weevil damage. Weevil resistance is discussed with respect to fertilization and water stress as determinants of seedling quality.Pinus sylvestrisHylobius abietis