1. The sight of swifts, swallows and sand martins wheeling through the sky is a classic summer spectacle. But try telling them apart in the air and it can be tricky. But with a bit of practice you can soon separate these high-flying long-haul migrants.
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3. Swifts, swallows and sand martins spend most of their lives on the wing – flying between their winter and breeding grounds and back again, eating, nest building, mending the nest and rearing young. They rarely land and their feet, although webbed, haven’t developed, so they can’t walk (but they often crouch to take perches such as buildings or fences).
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5. Swallows and martins are also acrobatic in flight and can be difficult to tell apart when flying together. But a key difference is that swifts look darker (but they still look black against a blue sky) and have longer narrow wings that make a scythe shape, while the other two species have broader wings and shorter, more forked tails. Also, whereas swallows and martins are a fluttering, chattering presence on the wing, swifts are much quieter, with a soft, short, twittering chirp.
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7.  xét nghiệm tầm soát ung thư cho nam nha trang can help our high flyers by providing suitable places to nest and roost, such as gaps in walls or in the eaves of buildings, or in a reedbed. You can also encourage them to visit your garden by planting flowers and grasses that they like, and avoiding pesticides and herbicides.
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9. House martins are common in towns and villages, where they build mud cup nests under the eaves of houses or ledges on cliffs. You may be able to see them visiting puddles to collect the mud to build their nests. The female and male share the work of collecting mud from streams and ponds. They are glossy black above and white below, with a contrasting white rump and short forked tail. They usually nest in colonies, often with several nests built side-by-side.
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11. They arrive in the UK in April and leave again in September or October, heading to Africa for their winter home. They feed on a wide variety of flying insects, including flies (including house flies and horse flies), beetles, wasps, wild bees and winged ants. They can also be seen swooping on the ground to catch aphids and caterpillars.
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13. The sand martin, which is less common than the house martin, lays between three and seven eggs that hatch after about two weeks of incubation. They hatch out of their sand nests and start to learn to fly after 23 days.
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15. Like house martins, they are attracted to a variety of habitats and nest in the eaves of houses, cliffs and reedbeds. It is more likely to be found in rural areas than in towns or cities. xét nghiệm tầm soát ung thư cho nữ khánh hoà feeds on a wide range of flying insects, but avoids moths, beetles and winged ants.
16. Website: https://mednovanhatrang.vn/goi-xet-nghiem-tam-soat-ung-thu-cho-nu-nha-trang/