NTNU staffer and photographer Per Harald Olsen has travelled the globe to photograph the natural world and all its inhabitants, but this eagle was photographed in Norway. Photo: Per Harald Olsen, NTNU.

Summer is for the birds

Five Gemini stories that detail the secrets of Norway’s bird populations.

BIRDS: Summer may mean holidays and fun in the sun for us humans, but for birds it’s a busy time. Especially at high latitudes, birds have a fairly short period during which they have to find mates, lay eggs and raise young.  Not surprisingly, some of our NTNU researchers have devoted their research careers to understanding the secrets of our feathered friends. Read on for five of our favourite Gemini stories about birds.

Razorbills. Photo: Per Harald Olsen.

Razorbills. Photo: Per Harald Olsen.

1. Uncovering the secrets of Arctic seabird colonies

Thousands upon thousands of seabirds nest in colonies on high cliffs along the Norwegian coast. But virtually all of the largest colonies are north of the Arctic Circle.  NTNU researchers have figured out why.


2. Why some cuckoos have blue eggs

Denne rørsangeren har fått en stor munn å mette. Dens egne unger ble det ingenting av. Foto: Per Harald Olsen, NTNU

This reed warbler suddenly has a big mouth to feed. Yet its own young are nowhere to be seen. Photo: Per Harald Olsen, NTNU

Cuckoos are master nest parasites: the females lay their eggs in the nests of other unsuspecting birds and let the other female bird feed and raise the cuckoo chick. But to slip her eggs into another bird’s nest, the cuckoo has to be a master at laying eggs of the right colour. Here’s the trick behind their artifice.


3. Ivory gulls in trouble

Ivory gulls are among the most northerly nesting birds on the planet. But just what is causing their populations to plummet by as much as 80 per cent over the last few decades?


4. Five kilometres between life and death

Havørn. Foto: Espen Lie Dahl

Sea eagle. Photo: Espen Lie Dahl

DNA profiles from the large population of sea eagles on Smøla, an island to the west of Trondheim, are providing new insights into how some birds are able to avoid being killed by wind turbines.


5. How do small birds survive the Norwegian winter?

It may be sunny and (sort of) warm in Norway now, but when winter comes, the days are short (and above the Arctic Circle, completely dark for some periods), cold, and often quite snowy. Yet small birds like blue tits and great tits somehow manage to overwinter. One of NTNU’s best known bird biologists explains how.