Show simple item record

dc.contributor.authorKoskimäki, Jane
dc.date.accessioned2011-08-30T16:11:48Z
dc.date.available2011-08-30T16:11:48Z
dc.date.issued2011
dc.identifier.otheroai:jykdok.linneanet.fi:1182297
dc.identifier.urihttps://jyx.jyu.fi/handle/123456789/36598
dc.description.abstractHuman land use causes declines of natural populations, for example, by loss of habitat area. Additionally, habitat fragmentation can cause the population size to decline more than is expected based on the area lost. Some ecological processes, such as demographic stochasticity and Allee effect, can expose already small populations to further decline. The endangered Siberian flying squirrel (Pteromys volans) has suffered from intensive forestry in Finland. In this thesis I estimated the size and growth rate of a local flying squirrel population living in nest boxes in Alavus using 15-year mark-recapture data. I regressed the estimated population size against habitat availability to detect relationships between the variables and also possible effects of fragmentation. The adult population size decreased from 65 to 29 in 1995–2009. The growth rate was less than one during the time period, also indicating a decline. The survival probability for adults was about 0.5 and for juveniles 0.22, both being constant in time and quite equal to another study in Finland. Population size declined with decreasing habitat area and the number of box sites, but no effect of fragmentation was seen, since the relationship between population size and habitat area was linear. There was also temporal variation in population size not caused by habitat availability but other reasons, for example demographic and environmental stochasticity or predator species. Therefore, the generalizability of single year census is not very good. Additionally, predicting the current or future population size only based on habitat availability is dangerous, which should be considered in the conservation of the flying squirrel populations. The availability of cavity and foraging trees is important for the persistence of the species. Maybe the conservation of the species also requires placing nest boxes to enable living in habitats of poor quality when preferred habitats are cut down. The nest boxes could have saved the population from extinction so far, but with similar forest cutting the population could go extinct in 15 years.
dc.format.extent24 sivua
dc.language.isoeng
dc.rightsThis publication is copyrighted. You may download, display and print it for Your own personal use. Commercial use is prohibited.en
dc.rightsJulkaisu on tekijänoikeussäännösten alainen. Teosta voi lukea ja tulostaa henkilökohtaista käyttöä varten. Käyttö kaupallisiin tarkoituksiin on kielletty.fi
dc.subject.otherhabitat fragmentation
dc.subject.otherhabitat loss
dc.subject.othermark-recapture
dc.subject.otherpopulation growth rate
dc.subject.otherpopulation size
dc.subject.otherPteromys volans
dc.subject.othersurvival
dc.titleThe temporal variation in Siberian flying squirrel (Pteromys volans) population size
dc.identifier.urnURN:NBN:fi:jyu-2011083011311
dc.type.dcmitypeTexten
dc.type.ontasotPro gradufi
dc.type.ontasotMaster’s thesisen
dc.contributor.tiedekuntaMatemaattis-luonnontieteellinen tiedekuntafi
dc.contributor.tiedekuntaFaculty of Sciencesen
dc.contributor.laitosBio- ja ympäristötieteiden laitosfi
dc.contributor.laitosDepartment of Biological and Environmental Scienceen
dc.contributor.yliopistoUniversity of Jyväskyläen
dc.contributor.yliopistoJyväskylän yliopistofi
dc.contributor.oppiaineEkologia ja evoluutiobiologiafi
dc.contributor.oppiaineEcology and evolutionary biologyen
dc.date.updated2011-08-30T16:11:48Z
dc.rights.accesslevelopenAccessfi
dc.contributor.oppiainekoodi4011
dc.subject.ysoliito-orava
dc.subject.ysoelinympäristö
dc.subject.ysohabitaatti
dc.subject.ysopirstoutuminen
dc.subject.ysopopulaatiot


Files in this item

Thumbnail

This item appears in the following Collection(s)

Show simple item record