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Bromley Local Group Bromley’ s Swifts The report of the first RSPB Bromley Swift Survey in 2018 March 2019 title Ben AndrewBen Ben Ben Andrew (rspb (rspb - images.com) - images.com) In this report… Find Find out outhow how local local citizen citizen scientists scientists stepped stepped upup forfor swifts Discover Discover Bromley’s Bromley’s swift swift hotspots hotspots Learn how you can help our swifts thrive 1 Learn how you can help save our swifts Roger Wyatt (Swifts Local Network) Swifts are the sound of summer but they need our help… Introducing swifts Swifts are the Olympians of will be to feed to replenish the nine months. Young swifts the animal world. No other energy lost during their epic sometimes fly non-stop for an bird can reach such fast migration. They will then meet entire three years, landing only speeds in level flight or up with their mate for life at the when mature enough to breed. travel for years without same nest site where they nested in previous years. touching down. They travel down through France and Spain. By late They are sociable birds and August they will be feeding Swifts are strictly urban birds like to nest in close proximity to over the jungles of the Congo. so there’s no need to travel each other. Located high up in Around Christmas they will long distances to a faraway the nooks and crannies under push on further south to nature reserve to admire them. our eaves or roof tiles, the nest Mozambique, close to the They nest in our buildings, is a simple little cup made from Indian Ocean, 6,000 miles from under the eaves or loose roof material they find floating in the Bromley. In late January they tiles. Their fast, acrobatic flight air. This aerial flotsam is glued begin the long journey back to and piercing calls are a together using saliva. our borough. quintessential part of warm summer days. Swifts normally lay two or three It is estimated that swifts fly an eggs. They hatch in early June average daily total of 500 miles A swift’s year and the first young leave their or more than 1.24 million miles nests in mid-July. They only in their lifetime. That’s equal to Swifts are one of our longest stay with us long enough to the moon and back – five distance migrants. They arrive breed. By late July or early times! They do everything on back in the UK in late April or August they will migrate south, the wing – eat, drink, sleep and early May. Their first priority flying non-stop for the next even mate in the air. 2 Swifts in trouble have now all but vanished from the area as new buildings replaced the old ones. Sadly, renovations to roofs and modern building designs mean This steep and steady decline that there are fewer nest sites means that swifts are heading for swifts now. Swifts eat for the Red list. Unless we take airborne insects and these are action now there’s a danger we also much scarcer too, in large might lose them altogether part due to changes in farming from Bromley’s towns. practices. Recent research has shown huge declines in global Figure 1. Data from the British insect numbers threatening not Trust for Ornithology’s (BTO) We can all play a part helping just swifts but many of our Breeding Bird Survey shows a give swifts a brighter future and 58% decline in Greater London’s other birds, other animals, we share our top tips later in plants and our whole life- swifts since 1995 this report. The area where we, support system. as individuals and as a group, the numbers of swifts in our can have the biggest impact is skies today compared to the by protecting and increasing Taken together, these two mid-1990s (see Figure 1). their nesting places. If we can factors have caused swift make sure that wherever numbers to decline. Swifts are During our survey in 2018 local possible new buildings contain now on the Amber list of birds people told us with sadness specially designed swift bricks of conservation concern in the about how rarely they see (bricks that contain cavities in UK following a decline of 53% swifts in the Bromley borough which swifts can nest) and fit between 1995 and 2016. compared to in days gone by. swift boxes on existing We learned that the area buildings, swifts will have Their numbers have fallen by around Bromley South train places to breed in future years. 58% in Greater London over station used to be a swift the same period. This means stronghold as recently as that there are fewer than half twenty years ago, but that they The aims of our survey The first step to saving Finding out this information in areas where there are no or Bromley’s swifts is to work means that existing swift few swifts. out where they are still colonies can be saved from nesting. Without this crucial being lost during renovations In early 2018 the RSPB information, we wouldn’t or demolition. Bromley Local Group decided know where to focus efforts to launch the first RSPB on safeguarding their Just as importantly, Bromley Swift Survey in the existing nests and creating discovering Bromley’s swift summer of that year. The aim hotspots will reveal the places was to gather vital information new ones. where it will be most effective about where swifts are nesting, to create new swift nesting that can be used to target Before the 2018 survey we sites. As swifts prefer to nest in conservation work. In the were in the dark about our close proximity with each process, we wanted to inspire borough’s swifts. There was other, creating new nest sites Bromley’s residents about very little information available in areas where there are these fascinating birds and about where they are still already swifts is likely to be build a community of people nesting in our borough – no more effective in increasing our who would be able to help more than a handful of swift population than doing this save them. scattered records. 3 How the survey worked Our Bromley Swift Survey Timing of survey Swifts that were high flying or followed a standard flying over open areas such as methodology that was visits fields, parks, open countryside, developed by scientists in lakes and waterways were to the RSPB to find breeding We asked surveyors to walk be ignored. This is because any such birds would probably swift colonies. along all of the public access roads in their square and be feeding, and it is known that record potential swift breeding swifts often feed many miles This methodology had been activity at least once a month from their nest sites. High successfully used by the RSPB in May, June and July, with flying swifts could be nesting to identify swift hotspots in recommended earliest and as far away as Germany. Brighton in 2016 and 2017. latest dates of 12 May and 26 AndrewBen (rspb July respectively, as this Survey squares comprises the main period of nesting activity. - We divided the London images.com) Borough of Bromley into survey As the peak times of swift squares of 500m x 500m, activity near nest sites are the based on the Ordnance Survey two hours after dawn and the two hours before sunset, it was (OS) Grid, and allocated them recommended that survey These low-flying swifts would to our volunteer swift be recordable. They are likely walks take place during this surveyors. A square of this size to be nesting nearby could generally be surveyed in period. In practice this meant around 45 minutes. that most survey walks took place in the evening. Survey forms The squares’ boundaries were not always neat with respect to Surveys were only to be the roads. Sometimes the carried out on dry, still days as Surveyors were asked to boundary of a square might run swifts may stop visiting their complete two forms: through the middle of a road, nests during periods of poor so that one side of the road weather. Incredibly, swift eggs 1. Survey Visit Recording would be inside the square, can survive without incubation Form and the other outside. Also and chicks can go into a state of semi-torpor for several days. there were cases where in The surveyor completed this order to access a road within a for each survey visit. In square a participant would What were surveyors addition to recording the need to follow a route that took location details and a count of them outside of the square. looking for? swifts seen, participants were asked to record swift behaviour This meant that we asked As swifts nest almost under the following categories: surveyors to report any swift exclusively in buildings, activity seen in the course of a participants were asked to only Low Flying Party: Swifts survey visit, even if it occurred record swifts seen at or just flying around roof height in outside of their square’s above or below roof height the vicinity of buildings. boundary. near to buildings. These low- flying swifts are likely to be nesting nearby so any records Screaming: Swifts heard We only allocated squares that of this behaviour are a good screaming as they fly past. included at least some indication that there are buildings, as only these would nesting swifts in the area. contain swift breeding sites. Arcs: Where any swift 4 comes within 1–2 metres of group of swifts will fly past buildings, often under the a building.