It’s been a tough time on the nest for the last 24 hours for our resident pair of ospreys NC0 and LM12.  In the last few days an unringed osprey has been persistently intruding on the nest, flying at NC0 and attempting to get her to abandon her eggs.

The size, behaviour and markings indicate that this is likely to be a young female prospecting for a breeding territory. She has been hanging about the reserve since Thursday, but on Friday continually flew in on our female NC0, who is incubating 3 eggs.   NC0 has been impressive at sitting tight on the nest and warding off the unwanted attention by alarm calling to her mate LM12 and flapping the intruder away. She has certainly proved she has a good pair of lungs on her when required.

LM12 clearly wasn’t keen in getting involved in a scrap – a wise move for the sole food provider of the family.  He did land on the nest briefly at 4:40am this morning, but was largely AWOL since his last incubation duty at Friday lunchtime.  This behaviour is not unknown for LM12.  In 2019, under similar circumstances he vacated the area for 24 hours, leaving his mate at the time LF15 to fend for herself.

Despite suspecting he wasn’t far away and that he appeared to have seen off the intruding female earlier in the day, we are relieved to see him return this afternoon to his favorite perch on the split birch, tucking into a large fish.

NC0, who had not eaten since Thursday evening has been loudly calling to him and food soliciting since he landed.  Now that LM12 has eaten his fill, she is now taking a well earned break off the nest and enjoying a good meal.

Whilst challenging for our birds to deal with, the frequent intrusions on the nest indicate a healthy population of younger birds are making it back to the UK to establish their own nesting sites. Hopefully for our pair the daily routine will be a little less fraught and calm will reign on the loch once more.  Keep watching our livestream to keep up to date with the action.

Sara ‘Raz’ Rasmussen
Perthshire Ranger