Saturday, November 25, 2006

My Favoritebird -The Hooded Crow

Hooded Crow Corvus corone cornix has been a projectbird for Utsira Birding station since 1993. We've colourringed chics in their nest since 93 and a total of 79 chics and two adults has been ringed up to year 2000. I've done a tribute to the Hooded crow on the municipal web. And presented the ringing data here. red (Killed), black (no records of chics since 1999), seen last in year 2000, 2001, 2002, 2003, and 2006.

Main results from the project: (read: 'seems to' or 'major tends shows..')
The chics stay in their nesting territoials until they are getting into their p
uberty 2 years old, supporting in their parens task, surch as finding food an beeng aggressive into intuders. (I've made a sycklic-Hooded-Crow-yearclock wich shows when agression take part. In winthertime all Crows cooporate and do'nt defend a territorial).
Their parents are "Apha-pairs" and stays together as long they live (about 20-25 years?) There are about 15 breeding pairs at Utsira. And the best alphapairs breeds 4 chics a year. Staturs report is publiced in Yearbok 00-01 of Utsira Birdstation. Only two Utsira chicks has been found at Mainland in Haugesund killed two and four years old.
Intra harmony (may-late august) harmony among relatives in the territorial.
Inter harmony (november-mid february) harmony among all crows (exept weak indiviuals who get killed by other crows!).
highest aggresion period (in mid february-may) Aggression towards non territorial crows (the young mob) and less aggresion periode september-november aggession towards their chics (prepearing them for what's to come?)

The SoutWestEuropeean subspecie Carrion Crow Corvus corone corone are also represented in high numbers at Utsira and we think that they are Scottish or Shetlenders youngsters who are been defeted by their parents an yonger brothers/sisters from their home terriotorials som later than the Hooded Crow in april/may (Hooded in february/march)

Also started the Norwegian Page on Hooded Crow on Wikipendia


Jimmy M. Espana said...

Cool looking bird.

Marg said...

This was really interesting to read, we don't have that many crows around here, West Nile wiped a lot of them out but they are coming back, your hooded ones are gorgeous!