Osprey Diary at Loch of the Lowes – Weeks 19 & 20

The last few weeks continue to be a challenging and testing time for the osprey family at Loch of the Lowes. When we last wrote NC0 (the resident breeding female) had not been seen since 15th July.  Sadly there still have been no sightings of her. Our working theory continues to be that the combination of a lack of hunting success in the area and the youngsters being fiesty enough to grab and defend a fish when delivered, (a key developmental stage in their journey to being independent), were triggers for her to head off to a more plentiful hunting ground and feed herself up prior to migration.

Despite the Ranger undertaking surveys in the wider area there is no way of knowing if anything else has happened. However, the staff and volunteers remain optimistic that given she is a strong and feisty bird herself, that she is feeding up somewhere without the attention of any ‘hangry’ teens! We’re keeping our fingers crossed that we will see her return next season, which of course would bring us all great joy and relief.

Resident adult female, ‘Blue NC0’ © Scottish Wildlife Trust Webcam

When we last shared the latest osprey diary, the young male ‘PF5’ had recently taken control of the nest, ousting his older, larger sister ‘PF4’.  Little did he know on Sunday 23rd that the tables were about to turn!  The day started well, with PF5 receiving a huge brown trout from his father LM12, however it nearly all ended up in disaster with the fish over the side of the nest! Thankfully PF5 managed to rescue the situation and tucked into his enormous ‘breakfish’!

It wasn’t long however before PF4 decided her younger brother’s time as ‘top osprey’ was over and began to launch a series of attacks to take back control of the nest. After being chased off, PF5 took his fish to eat in peace on the ‘Split Birch’, leaving the nest vacant for PF4 to dominate. This turned out to be a pivotal day in the life of these two young siblings. With PF4 now able to defend the nest, she was also in the best position to grab any fish deliveries from LM12, and she didn’t have to wait long before she received her own meal.

Having successfully stuck a flag in the nest and claimed it as hers, PF4 enjoyed several large meals over the next few days, whilst PF5 claimed another patch elsewhere on the reserve, where he was seen almost exclusively frequenting throughout the rest of the week. On occasions he was joined by LM12, however a steady stream of intruders also featured, including a very dark ringed Scottish female osprey (not NC0), a ringed English/Welsh female osprey and even an LM12 doppelganger – who was later chased off by the real deal himself.

Whilst we didn’t observe any fish exchanges in this area via security camera, it may have been that PF5 was managing to solicit fish from his father in another location.  He did manage to make a spectacular ‘smash and grab’ of a small fish on the nest on Mon 24th July, when he flew in at breakneck speed and took off with his prize in his beak before LM12 could barely blink!

The following day PF5 again tried again to reassert his authority on the nest, launching a series of blistering and breathtaking attacks on PF4.  Despite his incredible turn of speed and a number of spectacular chase sequences observed over the nest, PF4 maintained control and dominance of the nest.

For the next few days PF5 continued to be observed from his territory on the reserve and could be heard calling for food when deliveries were made to the nest.  It wasn’t until Friday 28th however that we saw him again try to get food from the nest. Despite following LM12’s flight path and arriving at breakneck speed to try and grab the delivery, PF4 defended her meal, which saw PF5 adopt the submissive posture he used effectively on the nest earlier in the season, (when he was much smaller and food was scarce).  Initially PF4 tolerated his presence, but as soon as he quietly began food calling PF4 became aggressive and again saw him off the nest.

Following his latest effort to be fed on the nest, PF5 returned to his ‘patch’ and hung out for several hours, before attempting to intrude on PF4 from height later in the evening.  This time however he did not attempt to land.

To date this is the last time we have had a positive sighting of PF5 or heard him calling on the reserve. However given he was flying well, we can only assume he has left the area to try his fortune elsewhere. It may be that he is managing to get food from LM12 from another location – there was a sighting off reserve of an adult osprey with a fish and a juvenile in hot pursuit on Friday, however there is no way of knowing if this was LM12 and PF5, especially given the high level of intruders in the area, including an unringed juvenile who was spotted on the security camera.

It could also be that PF5 is trying to develop his own fishing skills, after all hunger is a good motivator. It may even be that he is making a nuisance of himself on other nests, hoping to score a free meal, a behaviour that has been observed on other osprey cams over the years.

Meanwhile, PF4 continues to show dominance on the nest, even to LM12 when he arrives with any delivery! Whilst she is quick to try and grab any fish brought to the nest, her aim is more often than not on LM12’s talons, which has led to some fiesty interactions, with feathers flying and plenty squealing, often resulting in both birds tumbling out of the nest. Despite the dramatics, both birds are fine and have been observed flying around the loch each day this week.

Fish focused aggression is pretty common in juveniles who are in a period of food obsession known as hyperphagia. This is crucial in loading up as many calories as possible ahead of their first migration. That said, the challenging hunting conditions this year appear to have triggered an extra level of defensiveness in PF4 this year.

It’s been a challenging season of high emotion, angst and drama, however this edition of the diary does end on a high note! After several weeks of belly flopping and flapping, PF4 managed to catch her first fish on Monday night (31st July) – a wee ‘jack pike’ which she proudly took back to the nest to eat. Generally speaking young osprey do not really hunt ‘in anger’ until they head off on migration, some even completing the journey without fishing at all – so it is all the more encouraging to see PF4 take her first steps in mastering this essential survival skill!

After all the ups and downs of this season so far who knows what the next few weeks hold?  We will be sure to let you know if we do have any sightings of NC0 or PF5.

Osprey youngster PF5 © Scottish Wildlife Trust Webcam

Meanwhile, make sure you stay tuned to the live webcam! You can also keep up to date with the daily lives of the ospreys by following us on Twitter or Facebook for regular updates.

‘Raz’ Rasmussen, Perthshire Ranger

The Trust’s Osprey Protection Programme at Loch of the Lowes is supported by players of People’s Postcode Lottery.

Help protect Scotland’s wildlife

Our work to save Scotland’s wildlife is made possible thanks to the generosity of our members and supporters.

Join today from just £3 a month to help protect the species you love.

Join today


Preface

The last few weeks continue to be a challenging and testing time for the osprey family at Loch of the Lowes. When we last wrote NC0 (the resident breeding female) …

Posted in

Blogs -

Stay up to date with the Scottish Wildlife Trust by subscribing to our mailing list Subscribe now

Back to top