Geir H R Systad

Migration is a common trait among many animals allowing the exploitation of spatiotemporally variable resources. It often implies high energetic costs to cover large distances, for example between breeding and wintering grounds. For flying or swimming animals, the adequate use of winds and currents can help reduce the associated energetic costs. Migratory seabirds are good models because they dwell in habitats characterized by strong winds while undertaking very long migrations. We tested the hypothesis that seabirds migrate through areas with favourable winds. To that end, we used the SEATRACK dataset, a multi‐colony geolocator tracking dataset, for two North Atlantic seabirds with contrasting flight capabilities, the black‐legged kittiwake Rissa tridactyla and the Atlantic puffin Fratercula arctica, and wind data from the ERA5 climate reanalysis model. Both species had on average positive wind support during migration. Their main migratory routes were similar and followed seasonal...

Systad, G.H.R., Fauchald, P., Descamps, S., Christensen-Dalsgaard, S., Strøm, H. & Tarroux, A. 2019. Identifisering av viktige områder for sjøfugl i norske havområder – innspill til forvaltningsplanarbeidet 2019. NINA Rapport 1627. Norsk institutt for naturforskning. Denne rapporten omhandler viktige områder for sjøfugl i åpent hav og langs kysten, som et innspill til oppdatering av forvaltningsplanene for norske havområder i 2019. Delen som dekker åpent hav kobler transektdata med loggerdata fra fugler hentet fra SEATRACK-prosjektet under SEAPOP-programmet. Forekomstene relateres til bestandstilhørighet ut fra hekkekoloniene til fuglene som er merket med lysloggere. Bestandene er relatert til havområdene koloniene er tilknyttet, grovt sett klassifisert som Grønlandshavet, Barentshavet, Norskehavet og Nordsjøen. Ut fra disse datasettene er det beregnet viktige område for sjøfugl i åpent hav. Resultatet viser at områdene rundt hekkekoloniene er viktigst siden fuglene konsentreres i disse områdene gjennom store deler av året. Kystdatasettet beskriver anbefalte utvidelser av eksisterende SVO-områder langs Norskekysten og på de arktiske øyene samt forslag til opprettelse av nye slike. Anbefalingene er fokusert på beiteområdene til sjøfugl, og da spesielt pelagisk beitende sjøfugl. Områdene som er angitt, dekker stort sett havområdene 100 km ut fra koloniene, for eksempel rundt Bjørnøya. Modelleringen i åpent havdelen støtter denne tilnærmingen. I tillegg er det foreslått endringer av noen områder som dekker andre funksjoner enn hekking, for eksempel Ytre Oslofjorden

The conservation of migratory marine species, including pelagic seabirds, is challenging because their movements span vast distances frequently beyond national jurisdictions. Here, we aim to identify important aggregations of seabirds in the North Atlantic to inform ongoing regional conservation efforts. Using tracking, phenology, and population data, we mapped the abundance and diversity of 21 seabird species. This revealed a major hotspot associated with a discrete area of the subpolar frontal zone, used annually by 2.9–5 million seabirds from ≥56 colonies in the Atlantic: the first time this magnitude of seabird concentrations has been documented in the high seas. The hotspot is temporally stable and amenable to site-based conservation and is under consideration as a marine protected area by the OSPAR Commission. Protection could help mitigate current and future threats facing species in the area. Overall, our approach provides an exemplar data-driven pathway for future conservation efforts on the high seas.

Habitat use of Steller's Eiders Polysticta stelleri was studied in Varangerfjord, northern Norway, during three winter periods (November, January and April) in 1996/97. We partitioned habitats based on water depth and benthic conditions, and compared the benthic characteristics in known feeding areas to nearby areas avoided by Steller's Eiders. On average 88% of the birds were in natural habitats, outside of harbours. Mean water depth at feeding areas varied from 3.7 m in November to 2.5 m in April. Overall 89% of eiders foraged by diving at locations where water depths were less than 5 m. Steller's Eiders foraged in areas with underwater vegetation, predominantly in kelp beds. Two factors were positively associated (P < 0.05) with the probability that an area was used by Steller's Eiders: the proportion of the area covered by the kelp species Laminaria hyperborea and the vegetation density. Shallowly flooded kelp beds are the prime habitat for Steller's Eider...

In connection with a road project in the Torsken area
at Senja, Troms County, different alternatives were
considered in relation to animal- and birdlife. The
fieldwork was conducted during the summer 1997.
Otter activity was registered systematically in
Osterfjorden, and in the areas surrounding the tunnel
exits in Gryllefjord and Sifjord - Grunnfarnes. To
compare the alternative routes, the birdlife was
estimated by a point transect method. In addition,
potential raptor breeding localities was visited
specially. Information on game species was gathered
through the Wildlife register of the Fylkesmannen i
Troms.
In the area, it were high densities of the passerines.
Willow Warbler, Brambling and Sedge sparrow
dominated. The bird life in a rich, south turned
deciduous forest in Ostern had higher densities and
diversity than the rest. Species like Blackbird, Garden
warbler, Spotted Flycatcher, Wryneck and Lesser
Spotted Woodpecker was registered in this area. In
Northern Norway, all these species prefer rich and/or
old forest. At the tunnel exits in Grunnfarnesbotn and
at Hestelva, the diversities were relative high for the
passerines.
The European Otter needs access to freshwater and
hides in their habitat. High activity areas were found at
the mouth of Osterfjorden and in Skipsfjord. These
areas were characterised by good freshwater supplies
and boulders/rock crevices. They are variably affected
by the alternatives 2,3 and 4.
In the study area, there is two things which should be
considered: The bird life in the rich deciduous forested
mountain side in Osteren - and the Otter population.
These two aspects of the area is difficult to evaluate
against each other. The European Otter is classified
at the Norwegian red list as few in numbers and
sensitive. lt is relatively common in the area, but
Norway has an international responsibility for the
conservation of this species. Alternative 1 will not
affect the Otter areas, but will as alternative 3 and 4
open the Osteren area for traffic. Forests of the quality
of that in Osteren is rare in Troms. Old, intact alder
forest characterised by much dead wood is exposed to
deterioration in connection with introduction of spruce
and reconstruction to farmland. Because this forest
type is, among other things, characterised by high
densities of many bird species, the area is sensitive
and vulnerable.