I have been birding for 55 years, with 38 of those spent in Cambridgeshire. Last summer [2022] a truly exciting event took place in the county involving breeding Glossy Ibis. The news was kept quiet for the welfare of the birds, also with the hope that they would come back to breed again. This failed to materialise, however, and so now it feels safe to let the news out. I have also recently had confirmation via the Cambridgeshire county recorder, Jon Heath, that the record has been accepted as the first confirmed breeding of Glossy Ibis in Britain. Please note that the location of the nesting attempt has been withheld in this article.
This breeding-plumaged Glossy Ibis was present in Cambridgeshire in July 2023. Despite the presence of this bird, no evidence of breeding was noted, as in 2022 (Richard Atkins).
Prior to the following events, and since my return from birding abroad in April 2022, I had spent approximately 600 hours birding my patch. Up to 11 Glossy Ibis had been seen regularly. Below is a timeline of the events from August onwards.
6 August 2022: I noticed what appeared, at first glance, to be a young Common Moorhen clambering among the twigs. I thought it unusual because I don't recall seeing moorhens that high in a tree (perhaps 5 m). I put my telescope on it and, before it disappeared, I felt sure that it was a Glossy Ibis chick, having observed the young of this species at close quarters in Doñana in southern Spain. At this point I sent a message to the local Whatsapp group. A reply to this message informed me that this would be a first for Britain.
8 August 2022: Better views of the young bird climbing among twigs were obtained, its bill showing a grey-pink band.
9 August 2022: Better views still revealed that the bill was about half grown and that the chick was further developed that I had first thought. The young bird then moved out of sight. An adult appeared out of the foliage and came down to a point above where the chick had gone. The adult was observed regurgitating and appeared to be in the act of feeding what I presumed to be the obscured chick. Two other adults were seen mating and nest building.
12 August 2022: No fewer than 11 adults were seen leaving the breeding area as a flock. One returning moments later and disappearing into foliage.
13 August 2022: On my arrival seven adults were noted feeding in the lake below the nest site and the young bird could be seen in its usual place. Though heavily obscured, it could be seen that the bill had increased in length and its colour was fading.
15 August 2022: Seven adults were seen to depart but one returned almost immediately and was observed regurgitating and reaching down to feed the hidden chick on a lower branch. However, from my position, the chick remained fully obscured.
No further significant sightings were made for the following week, although often between seven and 10 adult birds would leave the nest area and then two to four birds would return almost immediately and disappear into deep foliage.
22 August 2022: Three adults and one juvenile were observed flying. The juvenile was noted to be approximately 10% smaller than the adults with shorter primaries, an obviously shorter bill and faster wingbeats. These four features were all noted by both observers present that morning.
23 August 2022: On arrival two adults were noted. One left and the remaining bird was joined by the juvenile which was seen to be begging. By now it was noted that the bill on the juvenile was long enough to fit within the adult range, but was still noticeably shorter and appreciably paler than that of any of the adults. The head and neck were clearly paler than those of the adults.
24 August 2022: Five adults left the site, one being unusually vocal. After flying no more than 200 m, the vocal bird turned and returned to the nest area. A juvenile appeared from the foliage and was seen begging from the adult. No food was given and the adult moved away, at which point a possible second juvenile approached, begging from the adult. No food was given. It is not certain whether this was, indeed, a second surviving chick, but it did emerge about 2 m away from where the first juvenile was seen moments earlier, and on the other side of the adult.
27 August 2022: 11 ibis left the roost/nest site as a flock, one appearing to have a smaller wingspan.
29 August 2022: 12 ibis departed as a flock.
All observations took place between 3.45 am and 6.45 am, with a total of 63 hours over 23 visits following the first sighting. After the 12 birds were seen to leave the nest area as a flock on 29 August, large numbers were not reported again in the area. It was a shame that breeding didn't occur again in 2023, but there is hope for the future.
The above photo shows the young Glossy Ibis, which landed briefly after a training flight before it disappeared into dense foliage. In the poor light of early morning, the pale streaks on the head and neck, indicative of a juvenile, were visible through optics but in the photograph show only as a pale head and neck, not observed in any of the breeding-plumaged adults present (Steve Hutchinson).
Thanks go to Rich Atkins and to RSPB staff, Richard Taylor, Tom Williams and Chris Hudson, all of whom joined me at these early hours on one or, in some cases, many occasions throughout this three-week period. Two of these people got to see the young ibis, while two weren't so fortunate.
Jon Heath has provided some context to the status of Glossy Ibis in Cambridgeshire: "This was a rare bird in the county, with fewer than 30 records prior to 2020. In autumn 2020, a small influx involving at least 10 birds occurred. These remained throughout 2021 and were even seen nest prospecting late in the breeding season. More ibises arrived in 2022, with breeding confirmed as above, plus the 12 birds represented a new county record count.
"A poor breeding season for Glossy Ibis in the Doñana NP in 2020 was followed by two mild winters in Britain – a set of events that was predicted to likely lead to the birds breeding in Britain (Ausden et al 2019). Having been displaced north, the wetlands of Cambridgeshire are seemingly just large enough to support a breeding pair of ibises. However, two very cold snaps in winter 2022-23 meant most of the ibises, along with Cambridgeshire's Western Cattle Egret population, retreated south – only one or two birds remained in 2023."
Reference
Ausden, M, White, G, and Santoro, S. 2019. The Changing Status of the Glossy Ibis Plegadis falcinellus in Britain. SIS Conservation, 1: 116-121.
