i flew all the way to south africa and still found your barn.
Swallow says
Bird 21 of 30 · video, 34:48
Swallow
Hirundo rustica
The summer bird: a long-tailed, long-distance flyer that feeds on the wing and goes back to the same nest site.
- Small, 19.9 g
- Summer visitor
- Building or eaves
- In the air
About the swallow
Marks and dots
Tap a numbered dot, or a name in the list.
The long tail is the tell against a house martin.
BTO says a red throat and a white belly.
From egg to adult
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Egg
Eggs4–5 eggs≠BTOthe video says 4–6 eggs
Hatch after16–18 days≠BTOthe video says about 14 days
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Chick in the nest
In the nest for21 days video, BTO agrees
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Young bird
Really late in the season, in late October, nestlings are sometimes abandoned as the urge to migrate overtakes the parents.
Adult
Long streamlined tail; red throat (BTO)
Broods a year2 broods≠BTOthe video says up to 3 broods
BTO averages: 18 days incubating the eggs, then 21 days in the nest. Averages across nest records, so the figures above can differ a little.
At the table
- insects, caught in flight
Catches insects on the wing, hawking for prey up to the size of butterflies.
Through the year
Swallow: around Mar to Oct; first arrivals, Mar; late-season nestlings sometimes left behind, Oct; first eggs laid 9 May to 31 Jul, average 5 Jun (BTO); first chicks leave the nest 14 Jun to 9 Sep (worked out from BTO).
What to know about the swallow
Eight short notes in our own words. Each chip says what the note stands on, and links to its row in the table below.
What to look for
Built for flight, with a long, streamlined tail that tells it from the shorter-tailed house martin it is sometimes confused with. BTO adds a red throat and a white belly.
Male and female
The video does not say whether male and female swallows look different.
not in the video
The young
Really late in the season, in late October, nestlings are sometimes abandoned as the urge to migrate overtakes the parents.
Song and call
The video does not describe the swallow's song or call.
not in the video
Nest
Builds its nest inside a building, often on a beam in an open barn or shed, or sometimes in a garage.
Feeding
Catches insects on the wing, hawking for prey up to the size of butterflies.
Staying or leaving
Leaves Britain each autumn and migrates as far as South Africa, a round trip of about twelve thousand miles by the time it is back in spring. Navigation is highly developed, and adults almost always return to the same nest site each year. BTO says the first arrive in March and stay into October.
In the garden
No other bird is so closely tied to the British summer. Swallow numbers have declined in recent years, which the video puts down probably to cleaner farms and so fewer insects.
Sources and checks
Where every fact about the swallow came from
20 claims about the swallow: 5 checked, 8 from the video only,3 differ, 4 from a source only. How the grades work
| Claim, in our words | Video time | Grade | What the source says |
|---|---|---|---|
| The swallow has a long tail. | 35:13 | checked | BTO, read 2026-10-05BTO describes a long, forked tail. |
| Its long, streamlined tail distinguishes it from the shorter-tailed house martin, which it is sometimes confused with. | 35:15 | video only | |
| BTO says a swallow has a red throat and a white belly. | source only | source only | BTO, read 2026-10-05BTO's introduction to the species. |
| Swallows leave Britain each autumn, migrating as far as South Africa. | 34:48 | checked | BTO, read 2026-10-05BTO says many British swallows spend the winter in South Africa. |
| By the time a swallow returns in spring it will have completed a round journey of about 12,000 miles. | 34:56 | video only | |
| Navigation skills are highly developed, and adults invariably return each year to the same nesting site. | 35:02 | video only | |
| BTO says the first swallows arrive in the UK during March and stay into October. | source only | source only | BTO, read 2026-10-05BTO's introduction to the species. |
| Swallows catch insects in flight. | 35:22 | checked | BTO, read 2026-10-05BTO says it flies at speed just inches above grassland, snatching insect prey. |
| They hawk for insects up to the size of butterflies. | 35:26 | video only | |
| No other bird is so closely associated with a British summer as the graceful, swooping swallow. | 36:04 | video only | |
| Swallow numbers have declined in recent years. | 35:29 | checked | BTO, read 2026-10-05BTO says declines have been seen in every UK nation since about 2010. |
| The decline is probably due to increased hygiene on farms, which has substantially reduced insects. | 35:32 | video only | A suggestion in the video. BTO's page names no cause. |
| The swallow builds its nest inside a building, often on a beam in an open barn, shed or garage. | 35:41 | video only | |
| Four to six eggs.video: 4–6 eggs | 35:49 | ≠differs | BTO, read 2026-10-05: 4–5 eggs (BTO typical)outside BTO's typical range of 4–5, though inside the 2–9 BTO has observed |
| They hatch after about a fortnight.video: about 14 days | 35:51 | ≠differs | BTO, read 2026-10-05: 16–18 days (BTO typical)outside BTO's typical range of 16–18, though inside the 13–23 BTO has observed |
| The young fly three weeks later.video: 21 days | 35:54 | checked | BTO, read 2026-10-05: 20–22 days (BTO typical)inside BTO's typical range of 20–22 |
| Up to three broods a year.video: up to 3 broods | 35:57 | ≠differs | BTO, read 2026-10-05: 2 broods (BTO typical)BTO lists 2 as typical and prints no higher figure, not 3 |
| In really late October, nestlings are sometimes abandoned as the urge to migrate overtakes the parents. | 36:00 | video only | |
| Adult weight, from ringing records: 19.9 g, adult average. | source only | source only | BTO, read 2026-10-05: 19.9 g, adult average |
| Timing of the first clutch: first eggs laid around 5 Jun (9 May-31 Jul). | source only | source only | BTO, read 2026-10-05: first eggs laid around 5 Jun (9 May-31 Jul) |
Written in our own words after “British Birds in your Garden” by The Great British Channel, where the swallow starts at 34:48.Numbers are checked against the BTO's page for the swallow, read on 5 October 2026. We are not connected to the channel or to the BTO.
More birbs: 30 so far, and more to come
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