Ups and Downs for Raptors

 Birds of prey, as apex predators, are often used as indicators of ecosystem health. Their fortunes reflect changes lower down the food chain and can help us understand how other species are responding to wider environmental pressures.

 I have accumulated enough data over the years to begin exploring these dynamics more meaningfully. So, when I recently found myself musing that I seem to be seeing Peregrines far more often than I used to, I dug a little deeper and put that feeling into context. That thought was really the combination of two separate observations: first, a Peregrine perched on Guy’s Cliffe House, and secondly, how rare it has become for me to see Kestrels at all.

Peregrine

Raptors have had mixed fortunes in the UK, and their numbers have changed drastically within my lifetime. As a child, seeing a Buzzard in Warwickshire was a rarity; now they are ubiquitous, and it is the Red Kite that still feels like a novelty. Kestrels were once abundant; no car journey felt complete without spotting one of these wind-hoverers over the motorway. As for Peregrines, those required a special trip to places like Symonds Yat. Thirty years have passed since my childhood, so what does my local patch tell me about raptors and how they have changed?

After watching the Peregrine perched on the house for a while, I returned home and looked back over the data I’ve collected. I keep a master database spreadsheet that tracks frequency, numbers, and abundance for all bird species recorded. When comparing species, I use a relative abundance measure that weights sightings by the time spent in the field. This helps account for extraneous factors that can otherwise skew results. I plotted these values as a graph and added some contextual information.

 I chose to look at all raptor species that have occurred on my site since 2004. Owls were excluded because my survey methodology substantially underestimates their numbers. When I first started recording, there were three main raptor species: Buzzard, Kestrel, and Sparrowhawk. This has since increased to five, with the addition of Red Kite and Peregrine.

 Buzzards have always been, and continue to be, the most abundant species. They are seen on practically every visit and, pleasingly, in 2024, they nested directly on the patch. Despite low rabbit numbers, their favoured prey, they continue to do well, raising two to three young locally. This mirrors the national picture, where Buzzards are now a stable and widespread species after expanding from their upland strongholds during the 1990s.

Sparrowhawk

 In contrast, Kestrels have undergone a serious decline over the same period and are now Amber-listed. The loss of rough grassland, agricultural intensification, and increased competition are all thought to be contributing factors. Locally, the decline was accelerated by a specific event. A tree in which a pair frequently nested was damaged when a winter storm in 2022 tore off the top of an Ash, exposing the nesting cavity. The loss of that single tree has had a noticeable effect on sightings. With low national numbers and no replacement pair moving in, the area has yet to be recolonised. Despite an abundant vole population in the meadow, I suspect this will remain the case for some time.

 Sparrowhawks are common across the site, as they are around the surrounding housing estates. They remain at a steady but relatively low abundance, which likely reflects their speed and ability to evade detection rather than true scarcity. As specialists adapted to hunting small birds on the wing, they face little competition from other raptors. Short-term peaks in the data likely reflect particularly successful breeding seasons rather than a long-term trend. National Breeding Bird Survey data suggest Sparrowhawk populations are broadly stable following their recovery from pesticide-driven declines in the mid-20th century.

Red Kite

 Pesticides such as DDT had perhaps their greatest impact on Peregrines, which came close to extinction in the 1960s. Their recovery stands as a flagship conservation success. Numbers have risen dramatically, and since the turn of the millennium, they have increasingly colonised urban and suburban sites. A local example is the nesting pair on Leamington Town Hall, which first bred in 2017 and have since raised more than 30 fledglings. My patch lies close enough to this site to be used regularly as a hunting ground, and many of this winter’s sightings appeared to involve an adult teaching a juvenile. Peregrines are territorial, so I don’t expect abundance to increase further — but wouldn’t it be something if they eventually nested in the ruins of Guy’s Cliffe House?

The final species of note is the Red Kite. I saw my first one when studying in Aberystwyth in the late 1990s, when the idea of them occurring in Warwickshire seemed laughable. Now they breed within the county and continue to increase in number. They first appeared locally in the early 2020s and are slowly becoming more regular, with the county still very much in the colonisation phase following reintroductions in Wales and the Chilterns. I hope breeding will occur closer to the site in future, though that will depend on factors such as nest-site availability and competition with Buzzards.

Buzzard and Kestrel

 So, what does all this say about raptors more generally? It’s clear that my small patch broadly mirrors regional and national trends. Generalist species like Buzzards and Red Kites appear better able to exploit our fragmented landscapes and varied food sources. It shows that when persecution pressure is lifted and sufficient nest sites are available, raptors can and do recover. At the same time, it highlights that some specialists continue to struggle. Sparrowhawks, despite their specialisation, seem to benefit from the widespread feeding of garden birds; here, there is nearly always an all-you-can-eat buffet somewhere nearby. Kestrels, by contrast, remain heavily reliant on rough grassland and vole populations, much as Buzzards once depended on rabbits.

My local story also illustrates how the loss of a single tree can significantly affect species abundance. In this case, the cause was weather rather than environmental vandalism, but it underlines how vulnerable populations can become once numbers fall. The takeaway is this: national recoveries are real but uneven; declines can be rapid and locally catastrophic; conservation often hinges on surprisingly small pieces of habitat; and patch-based recording matters. It really is the canary in the coal mine, and it contributes to the bigger picture.