A tale of two warblers – the ups and downs of birds in England
The newest BTO/RSPB/JNCC Breeding Bird Survey (BBS) report exhibits the very completely different fortunes in England for 2 nearly equivalent warblers, the Willow Warbler and the Chiffchaff.
Due to the various COVID-19 restrictions throughout the UK the 2020 BBS report can solely publish the most recent traits for a decreased set of species in England nevertheless it nonetheless makes for very attention-grabbing studying. Both the Willow Warbler and the Chiffchaff breed all through England and each are present in woodland, woodland edge and scrub habitats however their fortunes listed below are very completely different. During the final 24 years the Willow Warbler has seen its breeding inhabitants decline by 45%, while that of the Chiffchaff has elevated by 114% over the identical interval.
Willow Warbler and Chiffchaffs look very related and inhabit very related habitat throughout the breeding season, but they’ve a really completely different migration and
overwintering technique. The Willow Warbler is a long-distance migrant that spends the winter months in sub-Saharan Africa, while the Chiffchaff is a short-distance migrant that heads to Europe and as far south as North Africa – a few of our breeding Chiffchaffs might even keep right here within the UK throughout the winter months. So, it’s seemingly that they face very completely different pressures throughout the migration and overwinter interval which might be contributing to their very completely different long-term development.
Willow Warbler, copyright Glyn Sellors, from the surfbirds galleries
Two different woodland birds, the Nuthatch and the Great Spotted Woodpecker, have seen their populations greater than double over the last 24 years, up by 105% and 117% respectively however the identical can’t be stated of one other acquainted hole-nesting fowl; the Starling has seen its breeding inhabitants fall by 60% over the identical time interval.
For one fowl the change in its fortunes couldn’t be extra completely different from the handful of pairs that known as just a few Welsh valleys ‘dwelling’ within the Eighties. The report exhibits that over the past 24 years, the Red Kite has elevated by a staggering 18,695%. The reintroduction of this fowl to our skies now implies that many people can see them from our personal backyards and it’s unbelievable to suppose that as just lately because the early 80s, this wonderful fowl was heading in the direction of extinction within the UK.
Sarah Harris, BBS National Organiser on the BTO, stated, “2020 was a really troublesome 12 months for a lot of, and it seemed like we would have a really poor survey season for BBS protection and information; the primary since 2001 when Foot and Mouth stored us out of the countryside. However, restrictions had been lifted simply in time for a few of our good volunteers to get out and monitor their BBS squares, and it’s right down to them that we have now something to report on in any respect! Thanks go to all the present and retired BBS volunteers that we have now such a strong long-term dataset permitting us to observe the contrasting fortunes of species akin to Willow Warbler and Red Kite.”
Dr Mark Eaton, RSPB’s principal conservation scientist, stated, “Many of the UK’s birds are struggling, and the losses seen in these species should not sustainable. More must be executed to cease these declines and assist populations get well. Amazing examples of conservation in motion akin to for the crimson kite present what could be achieved with adequate dedication, information and sources. It’s been outstanding to see a species as soon as persecuted to close extinction on this nation, introduced again and welcomed by native communities, with native economies reaping the dividends of the return of this breath taking species.”
Dr Paul Woodcock, Biodiversity Evidence Specialist at JNCC Said, ‘It’s spectacular that regardless of the decreased information collected in 2020, dependable traits for a lot of species may nonetheless be produced from the BBS. This once more exhibits the worth of getting such a sturdy long-term dataset – thanks to everybody who has contributed over the years’.