Start by watching, not grabbing

The urge to scoop up a bird the moment you spot it is almost overwhelming, but the first minute matters more than the first action. Stand back, keep children and dogs away, and watch from a few metres. A bird that is sitting on the ground may be stunned, exhausted, sunbathing, or simply a fledgling waiting for its parents. A bird with a drooping wing, a visible wound, blood, a closed eye, or one that cannot stand or flutter away is likely in genuine trouble.

Ask yourself two practical questions. First, can it move away from danger on its own? Second, is there an obvious injury or a known cause — a cat, a window, a car, a dog? If the answer to the first is yes and there is no injury, the kindest thing is usually to leave it be and move the threat instead. If a bird has been caught by a cat, however, assume it needs help even if it looks unharmed. Cat bites and scratches carry bacteria that can kill a small bird within a day or two, and puncture wounds are often hidden under feathers.

• Keep your distance and use binoculars or a phone camera to zoom in if you can.
• Note the time, place and what happened — a rehabilitator will ask.
• Move dogs, cats and people away rather than moving the bird.

Contain the bird safely

If the bird does need help, a cardboard box is the best first-aid kit you own. Line it with a towel, make a few air holes in the lid rather than the sides, and have it ready before you approach. Approach from behind where possible, cover the bird with a light cloth or tea towel, and cup both hands gently around the body with the wings folded in against it. Never squeeze the chest — birds have a small, fragile ribcage and no diaphragm, so pressure there can be fatal.

Handle as little as possible. A bird's heart rate is already fast, and every extra second of handling adds stress that can tip a small species into collapse. Gloves are useful, and essential for birds of prey: a tawny owl or kestrel has talons that can grip hard and fast. If you are dealing with a heron, swan, goose or bird of prey, do not attempt to handle it yourself unless you have experience — call for help and keep people back.

Keep it dark, quiet and warm

This is the single most useful thing you can do. Place the secured box somewhere dark, quiet and away from radios, traffic noise, other pets and curious children. Darkness reduces visual stress and encourages the bird to settle; quiet reduces the noise it perceives as threat; warmth supports the body temperature that shock and injury cause it to lose.

Warmth is best provided with a hot water bottle or microwave heat pad wrapped in a towel and placed under one half of the box, so the bird can move away if it becomes too hot. Small birds, and any bird that is wet, chilled or oiled, lose heat very quickly. A bird that feels cold to the touch and is fluffed up and drowsy needs warmth before anything else — but never apply direct heat to skin, and never use a hairdryer.

• Do not use a wire cage, cat carrier with a mesh door, or anything the bird can see through.
• Avoid plastic bags and airtight containers entirely.
• Do not leave the box in a hot car or in full sun.

Why food and water can do harm

It feels counterintuitive, but offering food or water to an injured bird is one of the most common mistakes. A bird in shock or with internal injuries cannot digest properly, and food in the crop can cause choking or aspiration. Water offered in a bowl risks drowning a bird too weak to lift its head, and water in the mouth can run into the windpipe. Even a few drops can be fatal.

Wait for professional advice. A licensed rehabilitator will assess the species, the injury and the bird's condition before deciding whether to give fluids, and how. If the bird is with you for several hours and you have been told to wait, keep it dark and warm and leave it undisturbed rather than improvising.

Finding licensed help

In the UK, wild birds are protected by law and may only be kept by someone with the appropriate licence, so the aim of first aid is always safe transfer to a licensed rehabilitator or wildlife rescue. Contact one as soon as the bird is contained — most have phone lines and can advise on transport, box size and whether a vet should see the bird first. If you cannot reach a rescue, ring a vet practice and explain what you have; many will help or direct you.

When you call, have ready the species if you know it, the location, the likely cause of injury, and what you have done so far. Never attempt to treat a wound, splint a wing, remove a hook or clean oil from feathers yourself. Oiled birds in particular need specialist washing with the right detergent and temperature control, and handling oiled plumage with bare hands can expose you to the oil too.

When the best first aid is none at all

Many "rescued" birds are not injured at all. Fledglings — fully feathered, hopping, often noisy, with short tails — are learning to fly and are fed by parents nearby. Removing one is usually a death sentence. Similarly, a swift or swallow on the ground cannot take off from a flat surface; the correct response is to place it gently on a raised ledge or wall in the shade and let it launch. If you find a ringed bird, note the number before it goes anywhere, as that information helps conservation research.

Finally, look after yourself. Wash your hands thoroughly after any contact, disinfect the box and towel, and keep the bird away from your face. Report any dead wild bird, or a group of sick or dying birds, to the relevant national animal health helpline rather than handling them. Good first aid for wildlife is calm, minimal and quickly handed on to people with the training — and that restraint is itself a real conservation skill.