Jersey Birds
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22.09.2024 This great image of a Gannet with black eyes was taken locally by John Ovenden. The eye colour is an indication that this bird is a survivor of Avian Flu ( see the article from the RSPB, at the bottom of this report, for more information ) JO
A cloudy day following overnight showers, winds were light from the South
20 Little Egrets flew East over Pontac Co-op this morning with a Spoonbill for company, heading for Le Hocq.
Today's visible migrants at Noirmont included a late Swift, a Sand Martin, 523 Swallows, 8 House Martins, 141 Meadow Pipits, 3 alba Wagtails and a Grey Wagtail. On the ground, or dropping in through the morning, were a Song Thrush, a Wheatear, 3 Stonechats, 6 Whitethroats, 10 Chiffchaffs, 2 Blackcaps, 4 Dartford Warblers, a Spotted Flycatcher, 10 Robins, a Marsh Harrier, a Peregrine, 2 Ravens and 2 Choughs. Passing offshore were a Mediterranean Gull, 4 Lesser Black-backed Gulls, a Sandwich Tern, a Grey Heron and 10 Bottle-nosed Dolphins.
On the Scrape this morning were 13 Teal, 4 Shovelers. 3 Snipe, a Redshank, a Marsh Harrier and a Cetti's Warbler.
At Petit Port were 62 Mediterranean Gulls, 5 Lesser Black-backed Gulls, 65 Great Black-backed Gulls, a Whimbrel and 22 Curlews.
3 Song Thrushes flew over Vallee des Vaux at height this morning where a Firecrest and 5 Chiffchaffs were also seen.
Evening update: In St Ouen's Bay were 17 Ringed Plovers, a Sanderling, 158 Great Black-backed Gulls and 9 Lesser Black-backed Gulls and at Corbiere were 3 Wheatears, 25 Great Black-backed Gulls, 2 Ravens and 2 Choughs.
At the Farmer's Cricket Ground in St Martin were 3
Yellow Wagtails, 5
alba
Wagtails, a
Grey Wagtail
and 2
Swallows.
6
Cattle Egrets
were at Grouville Marsh, 15
Redshanks were at St Aubin and 57
Brent Geese were at Bel Royal.
Black eyes in seabirds indicates bird flu survival
Scientists have discovered evidence that Northern Gannets can recover from bird flu and that unusual black iris coloration is linked to a previous HPAIV infection
Ness Amaral-Rogers
Posted
Thu 4th May 2023
5 min read
- The study also assessed the impact of HPAI on adult gannet survival at the largest gannet colony in the world - the Bass Rock, UK
- The team found that at Bass Rock, adult survival between 2021 and 2022 was 42% lower than the average over the previous 10 years.
A new study has discovered evidence that Northern Gannets can recover from Highly Pathogenic Avian Influenza (HPAI) H5N1, with black irises, an indicator of a previous infection.
Scientists from multiple organisations investigated outbreak timings at colonies across their North Atlantic range. At their largest colony, Bass Rock, UK, a detailed study was conducted to estimate the impact of the virus on colony size, breeding success, adult survival, and whether Gannets were potentially able to recover from an infection.
Black irises – instead of the usual pale blue – were first seen in Gannets breeding on the Bass Rock in June 2022 with colour varying from completely black to mottled. The team took blood samples from 18 apparently healthy adult Gannets with both normal and black irises, which were tested for bird flu antibodies by APHA to determine whether the birds had been previously infected. Eight tested positive, of which seven had black irises.
Dr Jude Lane, RSPB Conservation Scientist and lead author of the study: “This has been a fascinating development and the discovery may prove a useful non-invasive diagnostic tool. The next steps are to understand its efficacy, if it applies to any other species and whether there are any detrimental impacts to the birds’ vision. Ophthalmology exams will also be needed to determine what is causing the black colouration.”
High Pathogenicity Avian Influenza Virus (HPAIV) has negatively impacted wild and domestic bird populations globally for decades. However, the current strain (HPAIV H5N1) has seen shifts in both the timings of outbreaks and species affected - including seabirds. Northern Gannets appeared especially severely impacted, but there was limited understanding of how their populations were affected.
High numbers of dead gannets were seen in Iceland during April last year followed by outbreaks in many Scottish colonies, Canada, Germany and Norway. By the end of June, outbreaks had occurred in five Canadian colonies and in the Channel Islands. Outbreaks in 12 UK and Ireland colonies followed in a clockwise pattern with the last infected colonies recorded in September. Unusually high mortality was recorded at all but one of the 41 monitored colonies (75 % of the 53 North Atlantic colonies), and sampling data was available for 58% of these, all with dead birds testing positive.
To better understand the impacts of HPAI, the team further investigated Bass Rock in the UK. Bass Rock is the world’s largest Gannet colony, home to over 150,000 birds at their peak. The team calculated that adult survival between 2021 and 2022 was 42% lower than the preceding 10-year average. The full extent of how many birds died during that period won’t be confirmed until the birds come back this breeding season.
The study was a collaboration between the RSPB, the University of Glasgow, the University of Edinburgh, Heriot Watt University and the Animal Plant Health Agency in partnership with the Scottish Seabird Centre.
Susan Davies, CEO of the Scottish Seabird Centre said: “Like many northern gannet colonies across the North Atlantic the Bass Rock was severely impacted in 2022 by highly pathogenic avian influenza. Due to the long running research effort on the Bass Rock, it was possible to gain important insights into the changes taking place in the colony with a strong link emerging between virus infection and the changing iris colour in these striking seabirds and the high level of nest failure within the study area.”
Seabirds are amongst the most threatened group of birds, out of the 25 species breeding here in the UK, 24 are Red or Amber on the UK list of Birds of Conservation Concern. The 2022 bird flu outbreak has provided another significant stressor to those already faced by our rapidly declining seabird populations. Quantifying and perhaps even mitigating its impact is therefore crucial if we hope to restore our seabird populations.
Mick Dryden
Romano da Costa
Tony Paintin
