Former RSPB Scotland staff member Amanda Biggins is now an active volunteer, monitoring one of Scotland's rarest birds. In today's blog, she updates us on their return to their Aberdeenshire breeding grounds.
Although I no longer work as RSPB’s Assistant Conservation Officer, I still volunteer to monitor our cranes in my spare time; collecting and analysing all of the important data on habitat use and breeding success. Since the first breeding attempt in 2012, 12 young cranes have fledged in Aberdeenshire. Most of them were raised by Pair 1, but following on from my last post in 2018, Pair 2 did manage to fledge their chick that year, but have not done very well subsequently.
Just the same two pairs bred in 2019 at two different sites, with Pair 1 successfully fledging twins for the second time. The amazing thing that year however was the number of non-breeding birds that visited the region: we reckon 22 in total.
Sharing views of Pair 1 male and six non-breeders with a very happy farmer, 30/04/2019, © Amanda Biggins.
One bird even chose to undertake a full wing moult at a bog on which restoration began just the year before. Being flightless for a few weeks is a risky business for a crane, which we were reminded about when it ran to hide from a dog running loose across the habitat. After regaining his wing feathers the monitoring team were treated to dancing display by this bird as it paired up and joined another four birds.
Displaying non-breeders, 05/06/2019, © Hywel Maggs
Both pairs arrived back super early in 2020, but monitoring was seriously hampered by the Covid-19 lockdown restrictions, particularly during the crucial incubation and hatching periods. It turned out that Pair 1 had moved nest sites once again, to a bog where restoration work had been undertaken. Their chick was already four weeks old when it was found in early June. The following week we heard about a photographer who had snapped a pair of Cranes in a roadside field nearby. Amazingly, on reviewing his photos he noticed a fluffy ginger head in one of them: they had a small chick!
Pair 4: a chick was spotted in the photograph, 09/06/2020, © Alex Jamieson
In fact, when we caught up with them, this new pair (Pair 4) actually had twins. These three chicks all went on to fledge, with both families remaining in very small areas throughout the chick-rearing stage. I was lucky enough to witness possibly the first ever flight of one of the Pair 4 twins: a parent rushed to guide it to safety after it almost crash-landed into a cow!
This is the first year when new first-time breeders could have been birds that hatched locally (as cranes usually don’t start breeding until they are five) and we think that at least one of the Pair 4 adults could be the offspring of Pair 1. A flock of seven tracked heading south on 7 October was probably the two families migrating together.
Pair 2 failed so early on we weren’t even sure if they hatched any chicks, and they became very elusive after failure, as they had the previous year. However, there was more than one new breeding pair. Two of three birds that arrived at our Loch of Strathbeg nature reserve appeared to settle in an area of reeds not far from the marsh harriers. Unfortunately, Pair 5 didn’t manage to hatch any chicks, despite seemingly making two nesting attempts. The second nesting attempt was only suggested by footage from a trail camera, amongst the roe deer and badger clips, as the birds weren’t seen that much after their first failure.
Pair 5 adult regularly caught on a trail camera at Loch of Strathbeg as it left the nest to go foraging, 06/06/2020, © RSPB.
A trail camera also recorded a pair feeding at a bog just to the south of Aberdeen City in early May. They were seen again in late June, but we don’t know if they spent the whole summer there. Another pair once again spent the summer around the Ythan Estuary / Forvie NNR, but still didn’t look like they were in a hurry to start nesting. A third summering pair possibly bred at Site 1 and may have failed with small chicks. At least three single birds also summered in the region, with one hanging around a bog which underwent some restoration work a few years ago, near the border with Moray. By 5 September, nine non-breeders had congregated at Loch of Strathbeg, joining Pair 5, treating many birders to views of the biggest flock recorded so far in the region.
11 Cranes at Loch of Strathbeg, 12/09/2020, © Walter Innes.
The nine non-breeders left Pair 5 at Loch of Strathbeg and headed south over Aberdeen City on 23 September and were seen leaving Caerlaverock WWT in Dumfries and Galloway the following morning. Two, probably Pair 5, headed down the east coast at the end of September, stopping off at Montrose Basin, before continuing over County Durham on 1 October.
All in all, this made 2020 a record-breaking year for breeding cranes in Scotland thanks with seven pairs.
Unfortunately, 2021 saw only three pairs attempting to breed. Unusually, Pair 2 was the first to arrive back (on 3 March). Three Cranes, which may have been Pair 4 with another bird, were tracked heading north from Cleveland and through Northumberland in the afternoon of 20 March. They continued through Northumberland, Lothian, Fife and Westhill (Aberdeen) the following day, and the three were found back on territory at 18:00 that evening. Despite being the last to arrive (on 29 March), Pair 1 were the first to get on with nesting, although Pairs 2 and 4 were only a week behind.
The cold spring meant that monitoring was strangely quiet at this time. It seemed to take a long time before even the calls of lapwings and curlews filled the air, never mind the migrant cuckoos and various species of warblers.
All three crane pairs were confirmed to have hatched young, but Pair 4 may have lost one at a very young age as only one young chick was seen. This may have been due to predation or the inclement weather (snow and hail) at the time of hatching. Pair 1 lost one well-grown chick, but at the time of writing the other chick was seen flying strongly. Better news is that Pair 2 have well-grown twins, so we are hopeful that they will manage to double their fledging output this year and bring the grand total up to 16 fledged.
Pair 2 with well-grown twins, 14/07/2021, © Ron Macdonald.
It is clear that cranes are now firmly established in the region and the high numbers fledged should soon increase the breeding population and colonise more of our wetland habitats. As we have found, bogs under restoration are quickly colonised. Bringing more of this precious habitat into favourable condition will ensure that the crane population can continue to grow and spread throughout the east of Scotland.
Both families remained in relatively limited spaces for the duration of the stage of chick raising io games, and all three of these chicks went on to fledge.