Thursday, 24 July 2008


Viewers of our main osprey nest will be as surprised as we were with the results of our chicks DNA results just in. During their health examination on ringing day a tiny blood sample was taken from each young chick to help screen for illness and to determine the gender of the birds. This is necessary because there are no real external difference between males and females- and the subtle differences in plumage can be very subjective and not clear until they are older. Since females in this species are always larger than males , and can have proportionally bigger legs, we often use this to estimate the sex of the birds during ringing. We used this technique on July 1st, and thought the largest two chicks were female.

Surprise, surprise, it turns out ALL THREE OF OUR CHICKS ARE MALE! We have only been using this technique for a few years, and it looks like it will turn up a few surprises.

So 2008 is the year of three wee boys- you can always guarantee a surprise with ospreys!


  1. Oooh! I wonder what ours will be. We are awaiting our DNA analysis here at Aberfoyle.

  2. What about the two chick on the backup nest - were you right with them?


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