Blue tit chicks in a natural nest hole looking a bit grumpy

Breeding birds, nests, eggs and songs

When is it safe to cut your hedge? How long does it take baby birds to fledge? Your bird breeding questions are answered by our team of experts.

Breeding birds, nests, eggs and songs

Your questions

Our landlord is re-roofing the buildings on our street, how do I preserve swift nesting sites? We don't get as many swifts as we used to. chevron-down

Sent in by Dick Hill, Swannington, Norfolk. 11 November 2012

 

Swifts are amazing birds providing a fantastic display during the summer months. It is certainly wonderful to hear them screaming through the skies and they are the most aerial of all bird species, being unable to walk or even stand. They really only leave the skies to breed, being true masters of the air.

 

Loss of habitat

Sadly, their numbers are dropping, and the main reason for this is the loss of their traditional nest sites. Their favoured sites include roof spaces in houses but when repairs are carried out, or plastic fascias fitted, then these are lost.

 

Ideally, a small entrance hole should be left so that they can still gain access to the existing nesting chamber, or a nestbox can be fitted within the roof. Special swift nesting bricks are available which can be incorporated high up, into a wall, on new builds. Swifts are very clean birds so little or no maintenance is required. 

 

Custom made nestsites

If none of this is possible then nestboxes can be fitted to outside walls, but need to be high up, in a shady spot, ideally facing north to east.

 

These swifts will return next spring and attempt to reclaim their nest sites.  If these have disappeared then they will be looking for alternatives so ought to soon spot any nestboxes but you can buy CDs of their calls to tempt them to new places nearby.

When is it safe to walk the dog in a field where birds might be nesting? chevron-down

Sent in by Alison Raynor, Northumberland. 14 September 2012

 

Having a dog to walk is a great reason to get out into the countryside. However, dogs can potentially disturb wildlife or livestock so it is important they are kept under control. Ground nesting birds are particularly vulnerable to disturbance. They may be forced from their nests, which would leave eggs or chicks exposed. Most birds will nest between March and September so disturbing nesting birds should be less of a problem outside this period.

 

However, disturbance can be a problem for birds outside the breeding season too, particularly in cold weather. Birds need to conserve their energy as much as possible and the presence of a dog could distress the birds and cause them to waste valuable energy at a time when food is hard to come by. This can be significant problem for wildfowl and waders in particular because they can struggle to find areas of unfrozen water in cold weather.

 

We encourage responsible dog walking, and ask dog owners to keep your dog close to you, preferably on a lead and stick to designated paths in areas where wildlife or livestock could be disturbed.

 

Dogs are welcome at many RSPB reserves but our reserves are very varied, so there may be restrictions at certain sites to protect the wildlife there. We would recommend checking with the reserve you are planning to visit what the access arrangements are for dogs.

 

Natural England's Countryside Code has further information for dog walkers in the wider countryside available here https://www.gov.uk/government/publications/the-countryside-code

Do wild birds live in nests all year, or only when raising their young? chevron-down

Sent in by Frimley Green, Surrey. 20 April 2012

 

With most species, the nest itself is purely constructed to hold the eggs and chicks. However many species will use the nest site outside of the nesting season as a place to sleep.

 

Nests come in all shapes and sizes and a variety of different materials are used in the construction. Some species like collared doves for example create fragile nests out of twigs, often in precarious places like behind satellite dishes! Blackbirds on the other hand build intricate nests, usually in climbers, trees or shrubs, using mud to stiffen the structure and woven bits of grass and twig, lined with soft material such as moss and feathers. These nests usually only last through one nesting season, often falling apart in the autumn and winter when the birds have finished using them.

 

Swallows and house martins make their nests from wet mud, which they expertly craft into solid cups that stick to their chosen walls and beams. They use these to raise their families throughout their stay through the British summer, often having three broods in the same nest and also using it as a safe place to roost. When they return to Africa they do not build nests but find safety in numbers in shared roosts, often at reedbed sites where they perch together on the reed stems.

 

Cavity nesting birds such as members of the tit family, tawny owls and woodpeckers for example may use the same cavity to sleep in overnight as they did for nesting. However these species usually have a number of possible sites in their territories where they can roost. Many people with nestbox cameras can watch birds breeding in the box through the summer and also have the pleasure of watching a bird return over winter to sleep in the safety of the box. However, species that winter in the same site as they bred won't build a nest for such purposes, the box or cavity itself provides sufficient protection from the elements.

Do 'our' swallows breed in South Africa? chevron-down

Sent in by Peter McKendrick, Northumberland. 1 September 2011

 

A very topical question, as we make the most of seeing our summer migrants overhead before they head southwards until spring next year. Many have of course long gone, and already arrived in their winter quarters following a fantastic journey of several thousand miles. Swallows and house martins, however, are often feeding young during September so linger awhile until they are all ready to migrate. 

 

Swallows have a very long journey indeed so will, with luck, have enjoyed a good supply of insects in the UK to enable them to gain weight. They need this to sustain them, as they complete long stretches of their journey without food and water. 

 

When swallows arrive in their winter quarters, they spend most of their time feeding and probably resting. They do not breed but make the most of the insects which are in abundance there to ensure that they are in tip-top condition for the return journey and another hectic breeding period awaiting them.

 

Before migration was understood, and because birds such as swallows completely disappeared, it was thought that they buried themselves in thick mud beneath water to sit out winter, surfacing in the spring. Understandable really as there was no trace of them anywhere else. 

 

We now know much more about the wonder of migration and the remarkable journeys of tiny birds; I'm already looking forward to their return next year.

What sings when in the dawn chorus? chevron-down

Sent in by Stephen Gawen John Sellick, Enfield.

 

Unfortunately, it is not all that clear cut. This confusion is due to nocturnal songsters, usually robins, that regularly sing throughout the night. 

 

Robins can forage in dim light so will often be active after dark. They are territorial all year round, not just during the breeding period, and will regularly be heard in full song at night. This can be triggered by bright, artificial lighting but this is not always the case. 

 

So, it is hardly surprising to note that robins are considered to be first bird to be heard in the dawn chorus. The lone chorister for a while but soon joined by song thrush and blackbird, wren, dunnock and great tits with house sparrows and many finches bringing up the rear. 

 

Dawn is probably the most tranquil time of the day so a great time for birds to sing to claim territories and mates. 4am is the average time for the dawn chorus to begin in early summer but some birds will be heard much earlier. Often it is still dark and not great for foraging so, what's a bird to do? Burst into song is the answer and aren't we glad that they do? 

 

It makes an amazing, joyful sound for us on a spring morning but, for the birds, it is full of purpose and ambition. 

Is it common for different birds to reuse the same nest in one year? chevron-down

Sent in by Stuart Nichols, Liverpool. 14 July 2011

 

Stuart said: 'We have a pair of robins who have set up home in an old blackbird nest in our garden. Both the blackbird and now the robins have had chicks in that one nest in one season. Is it common for birds of different species to reuse nests?'

 

That's a lovely story and not one we hear often, but birds can be very resourceful when looking for a place to lay their eggs.

 

Some birds have it easy and their nest is merely a small hollow scraped out of the ground, but others are intricate, woven structures.

 

Birds can use a variety of nesting material, from lichen and cobwebs to strips of metal of varying sizes. (The latter items, not regularly used I must admit, were bagged by a pigeon, nesting on a building site, taking advantage of some handy materials for its own construction work) Clearly though, if birds can reuse a nest built by others, it saves a great deal of time and effort.

 

Both blackbirds and robins have several lots of young each year. If they build fresh nests each time that's a great deal of hard work. Feeding and caring for lots of babies is extremely strenuous too, so it seems very sensible of these robins to use a nest that was already built. It's probably a des res in a sought after location!

 

Time saving, nest-building measures include stealing materials from other birds' nests and snatching twigs, moss etc already gathered. So watch out for house sparrows having a tug of war with some fluffy pampas grass - and the ultimate, be like a cuckoo and leave all that construction and parenting work to others!

Do blue tits hiss? chevron-down

Sent in by Rita Norman, Suffolk. 1 July 2011

 

This is a great question and one that we get asked a number of times every summer. Many birds that nest close to humans can be very vocal and their calls are often familiar. However, wild birds are full of surprises and the noises they make are a classic example.

 

If you heard hissing from a nestbox occupied by blue tits, it's most likely that the sound is coming from the female blue tit defending her brood.

 

Hearing a hissing sound in the garden can be quite surprising and even stressful for some humans, especially those with a fear of snakes! However, in most cases, the culprit is unlikely to be a snake, especially if it is emanating from a nestbox.

 

For such a small bird with many predators, they need to be able to scare off potential threats. This loud hissing display is an effective deterrent to many intruders and even potential predators. However, if you are hearing it, that means you are probably a bit too close, so back away and allow her to settle down again.

 

Young blue tits also make a range of noises through their development, but none quite so harsh as the female's hissing display. However, the calling for food by some other garden birds is very similar. Young robins for example when being fed can make a repetitive, hiss-like sound, almost metallic in quality.

 

So if you hear hissing sounds coming from shrubs or climbers in the garden, you may well have a nest very close by. Adult robins are also among the other species that will hiss when threatened as part of their distress or anti-predator display.

How often do great spotted woodpeckers eat other birds' chicks? chevron-down

Sent in by Barry Lewis, Sale, Cheshire. 2 June 2011

 

The great spotted woodpecker is an omnivore which eats a mixture of insects and seeds (mainly conifer). But they'll also take eggs and even young birds from nest holes and boxes.

 

This is probably Europe's most belligerent woodpecker species. They threaten and fight with each other, usually over foraging territories, and larger chicks will peck and sometimes kill the runts in the brood while in the nest cavity.


 
Great spotted woodpeckers also routinely attack nestboxes, especially those with tits nesting inside. They will drag nesting material out of the box and both eggs and chicks are lifted out and either eaten in situ or taken away for 'processing'.

 

Nestboxes fitted with a metal plate can deter woodpeckers from pecking away at the entrance hole. However, determined woodpeckers may try to make holes elsewhere on the box. A study by Lancaster University found that when covered in wire mesh, only 1 out of 48 blue tit nest boxes were predated. However, this may provide a climbing perch for other predators such as squirrels.

When can I move a starling nest from my loft? chevron-down

Sent in by Angela Jeffery, Northamptonshire. 20 May 2011

 

Starlings love nothing more than a cosy space, in a roof or loft, for their nests. Although they are noisy, they seldom cause any damage and their nesting period is fairly short.

 

Only when you are certain that a nest is no longer in use, can it be removed as active nests, for all birds, are fully protected by law. May is the peak month for nesting starlings and many have already fledged. You will see, and hear them, chasing their parents and begging for food - very demanding youngsters.

 

However, it is possible that, despite the strain of rearing one brood, the adults will nest again.

 

A good tip is to provide a starling nestbox, close to where they are entering the loft, and the chances are they will use this instead. This will benefit starlings for years to come and they need all the help we can give them. Their numbers have declined so dramatically that they are a 'red-listed' species, being of high conservation concern.

 

Helping them with accommodation is one thing we can all do. I have two boxes on my house and the starlings love them. They make charming, amusing neighbours.

We have a swifts' nest up in the gable end of our house. Half the nest broke and fell to the floor. Should I remove the rest or will the swifts rebuild it? chevron-down

Sent in by Daniel Burnett, Grimsby, Lincolnshire. 18 April 2011

 

Since swifts nest in cavities within the roof space, you would not be able to see a swift's nest from the outside. What you have in the gable end of your house will be a house martin nest. 

 

House martins build mud nests on the outside of buildings under an overhang; eaves with an open aspect that allows the birds to fly uninterrupted into the nest are favourite nesting sites.

 

I think it is best if you leave the remains of the nest where they are, and let the birds themselves do whatever DIY work they feel appropriate. We have had a very dry spring, and when the birds return from their migration, they will have a hard job finding mud to rebuild their nest.

 

In dry conditions like this, river banks and pond edges are popular sources of mud for the birds. If such sources are not available with about half a mile from you, the best way you can help your martins is to provide them with a muddy patch in your garden from where they can get the building materials.

 

This muddy patch can be a piece of soil you water to keep it wet, a wet area of soil at the edge of a garden pond, or even a plant drip tray or a dustbin lid with muddy wet soil in it. Hopefully the house martins will find it, and make good use of your offerings.

 

Since many other garden birds, including blackbirds, use mud in nest building, your muddy patch could be more popular than you might at first think.

Is it too early to expect the dawn chorus? At 5 am today I could distinctly hear five birds, rather than a joyful cacophony. chevron-down

Sent in by Carole Jefferson, Loughborough. 31 March 2011

 

Birds are certainly having a rehearsal at the moment and the 'joyful cacophany' is merely waiting in the wings. Some birds will have been singing for several weeks with blackbirds and robins being joined by song thrushes as they defend territory and attract mates.

 

During April many others, including summer migrants, will join in as it reaches a peak during early May. Since the clocks sprang forward, many of us have been entertained by birdsong without having to rise any earlier. This won't last for long though, and, as daylight stretches, many birds will have fallen relativey quiet by the time we are up and about.

 

This year, International Dawn Chorus Day falls on 1 May. By then, you will need to be up by 4 am or even earlier, as the first birds tune up about an hour before sunrise. If you're not an early bird don't despair; the dawn chorus builds up gradually as more songsters join in. Don't linger too long in bed though, or it will all be over.

 

So, your five birds will soon be joined by many, many others, and a glorious sound it will be too.

How do birds know when it is time to build a nest? chevron-down

Sent in by Adam Robinson, Northern Ireland. 17 March 2011

 

There are lots of factors which trigger the start of birds' breeding seasons. As with most vertebrates, hormones such as prolactin control changes inside the birds.

 

However, conditions in the environment are often the triggers for the hormonal changes to begin. One of the most well-known influences of bird breeding behaviour is day length (or 'photoperiod').

 

For birds which are active during daylight hours ('diurnal'), the lengthening of the days is a sign of the start of favourable conditions for breeding. Change in temperature can also be an important factor, as can abundance of food.

 

In the UK, spring is when most species show a distinct change in behaviour, spending much more time on activities related to breeding such as singing, territory defence and looking for nest sites.

 

The external triggers for this are noticeable all around us. The weather is getting milder, more food is available - in the form of fresh buds and insects - and the days get longer.

 

However, some birds breed much earlier or later in the season, when the weather may still be harsh and day length is decreasing. This may be linked to the abundance of a specific type of food that is abundant at that time.

 

For example, crossbills are opportunistic breeders that time their breeding to coincide with the abundance of pine cone seeds, even if that means starting breeding in December or January.

Do crows regurgitate food to feed their chicks? Would the extinct Hawaiian crow also have done it? chevron-down

Sent in by David Reamer, Colorado, USA. 3 March 2011

 

Yes, crows are one of the many birds that will regurgitate food for their chicks.

 

The diet of many members of the crow family is quite broad and can range from carrion, eggs, insects, small vertebrates and molluscs to vegetable matter and grain during winter. Having been fed regurgitated food for a short while, young crows are then fed worms and maggots by both parents before moving onto larger, meatier food.

 

As a family, crows are highly intelligent and opportunistic and can employ an arsenal of feeding and foraging strategies that can involve burying and caching food as well as dropping food with a hard shell from a height, so as to get to the contents.

 

Though some remain in captivity, the last two known wild Hawaiian crows, or 'Alala (their Hawaiian name), disappeared in 2002 and the species was confirmed as extinct in the wild in 2004.

 

A study conducted in 1979 in the Honaunau Forest Reserve showed that Hawaiian crows also regurgitate food for their young. The breeding season for Hawaiian crows stems from March to July and the female will potentially lay up to five eggs, only two of which would survive. Little is known about the ecology of this crow and its demise is likely to be a result of habitat change and fragmentation and illegal shooting.

Why do birds have to sit on their eggs and for how long? chevron-down

Sent in by Badger Class at Loose Infant School, Kent. 10 February 2011

 

Birds have to sit on their eggs to keep them warm. It's a bit like baking a cake - the warmth from the parent bird makes sure that the chicks inside develop properly. This is called 'incubation'.

 

To keep the eggs warm, a special warm patch grows on the parent birds' tummies. Some of their feathers drop out so that the warm skin touches the eggs. This is called a 'brood patch'.

 

Different birds sit on their eggs for different lengths of time. Bigger birds lay bigger eggs which take longer to hatch. Blue tits incubate their eggs for two weeks but swans sit on theirs for nearly six weeks!

 

Most birds lay one egg a day until the eggs are all laid. Some birds lay up to 15 eggs but others lay only one. But the parent birds do not start to incubate the eggs until they are all laid. In some birds, only the mother sits on the eggs. Others take it in turns to share with the father.

 

And in a very few bird species - like red-necked phalaropes and dotterels (which are rare wading birds) - only the male incubates the eggs and raises the chicks.

Do birds reuse old nests from year to year? chevron-down

Sent in by Judith Mower, Kessingland. 12 August 2010

 

Many birds, including swifts and swallows return to the same nest-site each year but most nests, found in trees and hedges, are seldom used more than once. 

 

Even birds like blackbirds and song thrushes which raise several broods each year generally use a new nest each time. But they do save a bit of time and effort by dismantling the old nest and recycling some of the pieces for the new build.

 

The size, shape and complexity of nests vary widely. Some are hardly nests at all, just hollows formed by the body of the bird, or cavities in trees or amongst rocks. Others are intricately complex, woven structures composed of a large amount of material. 

 

It is often the female who is the master builder but a well-known exception to this is the wren. The male wren works extremely hard building several nests throughout his territory then escorting his mate to view his handiwork and allowing her to choose where she will lay her eggs. 

 

Twigs, moss, wool, feathers, leaves and even cobwebs are popular nesting material but one pair of birds, probably jackdaws or crows built a nest entirely of metal wire which was tightly woven into the traditional circular shape. Closer inspection revealed that they had included a metal coat hanger and spectacle frames for added interest.

 

With all this hard work you would think that nests would be used over and over again, but this is seldom the case. 

Do blue tits get food for their young at a distance from their nest? chevron-down

Sent in by Roger Dobson, Stockton on Tees. 14 July 2010

 

Although blue tits are territorial, they do get a proportion, sometimes a significant one, of their food from outside their territory. Where they go is all dependent on where the best sources of the right sort of food are.

 

Blue tits feed their young with certain moth caterpillars in preference, and are prepared to travel some distance to collect the right food for their family. Generally speaking, broadleaved trees carry better insect crops than conifers, and native trees are better than exotics, although there are exceptions.

 

The best tree of all is the oak. It supports a good crop of winter moth caterpillars, and a large quantity of other insects, and given the choice, blue tits would spend the bulk of their time foraging in oak trees.

 

Blue tits are prepared to travel some distance to collect the right food for their family.

 

Birch and hawthorn are other good sources of food. When I was researching the habitat use of woodland birds, including blue tits, I discovered that if there were oaks, birches and hawthorns close to the nest, blue tits did not stray far from their nest in their search of caterpillars for the chicks.

 

However, I did find some birds nesting in nestboxes in the middle of a conifer plantation. These birds completely ignored the nearby trees, and brought all food to the nest from the streamside broadleaved trees some 200 metres away.

 

I suspect that your local blue tits have discovered the right kind of trees at some distance from you, perhaps in a nearby wood or in a neighbour's garden.

 

If you would like to encourage them to stay closer to home in future years, the right kind of planting will help. While oaks tend to grow too big for most suburban gardens, most gardens can take a tree the size of a birch or a hawthorn.

 

Have a look in the Homes for Wildlife pages for lots more advice on what to plant to provide food for birds.

Will the house martins have left their nests by the time our apartments are due to be decorated? chevron-down

Sent in by Eileen Saunders, Kent. 25 June 2010

 

House martins arrive in the UK during spring and are here until the autumn when they return to Africa.

 

Because they usually have at least two lots of young, sometimes three if conditions are favourable, their nests contain either eggs or chicks from May until August. Even in September there may be a few nests still in use.

 

It is illegal to damage or destroy active nests so, during redecoration, these nests must be left intact or the work delayed until the autumn. If necessary, when the birds have left in September/October and it is clear that these nests are no longer in use, they can be removed.

 

To prevent nesting in the future, the triangle under the eaves must be closed in with wood or fine mesh chicken wire. This needs to be done when the birds are absent so from late autumn until they return in the spring.

 

However, house martin numbers have declined greatly in recent years so it will help them enormously if traditional nesting sites can be left intact. Only restrict access to areas, such as those above doors and windows, where droppings in the vicinity of the nest may cause problems.

We have six young robins, but a female blackbird has taken to sitting with them. Is this normal? chevron-down

Sent in by Phil Butcher, Ilford Essex. 7 May 2010

 

Funnily enough, this is something the Wildlife Enquiries team have received several calls about in recent weeks.

 

I wouldn’t describe this as a 'normal' behaviour, but there is perhaps a more logical explanation to this. The most likely cause is that the blackbird’s nest has been abandoned due to disturbance, destruction, predation of the adult male or a lack of food availability. The female blackbirds parental instinct will be exceptionally strong at this time as an urge to tend to her young. The stimulus of seeing these other chicks calling in the nest for feed activates the instinctive response to brood the young robins when her own have been lost.

 

The safety of these young robin chicks will all depend on the temperament of the female blackbird. Some blackbirds can be highly aggressive and drive all other birds away. Some may not really know what all the fuss is about without any intent to harm the young and as such, may deny the true parents access to the nest at a time when every meal is critical for their chances of survival. Whereas others may be far more placid and if anything, bring additional food for the young which obviously improves the chances of survival. 

 

Inter-species brooding like this is most often reported amongst thrushes. However, we have also had reports of blackbirds sticking their heads in the nestboxes of blue tits to feed their young! Perhaps the most famous bird to parasitize the nests of other species is the cuckoo, which rather than being broody, will intentionally leave its eggs in the nests of dunnocks, reed warblers and meadow pipits.

 

We’d love to see and hear about more examples of this behaviour. Any chance you could share your pictures with us on the our online community?

Is it right that young starlings return to the nest they fledged from to breed themselves? chevron-down

Sent in by Lynne McBride, Edinburgh. 24 February 2010

 

You are lucky to host a pair of breeding starlings in your house. Starlings numbers are still declining, and so they need all the help they can get to survive.

 

Starlings nest in what can be termed loose colonies, where the nests are spread over an area of a few hectares. The birds you see occupying the nest from one year to the next are likely to be adult birds that had bred in the same colony, even in the same nest hole the previous year, or first time breeders that have arrived from outside the colony. Very few birds that were raised in the colony return to it to breed.

 

Once young starlings leave the nest, they are unlikely to ever return to it. All birds have an in-built mechanism that reduces the chance that they would mate with their own parents or siblings. The young starlings' instinct tells them to disperse, and that same instinct tells the females and males to travel, on average, different distances to find a colony where to find a mate and raise their own young.

 

You can help starlings by taking part in our wildlife gardening project: Homes for Wildlife.

We have a very strange looking nest in our loft. It almost looks like plastic. What can it be? chevron-down

Sent in by Monica Munro. 10 February 2010

 

Quite a few creatures will use of roof space as a home, which in some cases can be great for them and us. Swiftsstarlings and house sparrow are all great urban birds to have around and all find their way into roof space through gaps in the fittings or between tiles. The swift does not really build a nest other than laying a few feathers down which it grabs from mid air. Starlings and sparrows build messy nests from twigs and grass, usually in a recess or cavity. I think you can rule a bird out of the list of suspects!

 

If this plastic like nest were hanging from the beams then I would think it is the handy work of a wasp. The common wasp (vespa vulgaris) frequently builds its nest in roof cavities as well as underground burrows and tree cavities. The material the nest is made of is actually wood which has been chewed up by the wasp into a paper like material. The nest is usually cone shaped and can reach the size of a football. These structures are incredibly ornate and are truly amazing constructions for such a small creature to make.

 

Wasps do not have a great reputation, when they sting it can really hurt! However, before deciding to get rid of wasps and their nests, consider their role in the garden habitat. Wasps are active predators that feed their fast growing young on insects, many of which are garden pests that eat favourite flowers and produce. The wasps are therefore a brilliant form of biological control so should be left to their own devices if it is possible to do so.

Do black and white swans interbreed? chevron-down

Sent in by Janet Fearns, London. 4 January 2010

 

As a general rule, no. Mute and black swans won’t breed or hybridise, although as with everything, there are always exceptions to this rule!

 

Wild black swans are native to southwestern and eastern Australia. They have been introduced to New Zealand and are popular as ornamental birds in Europe, and localised areas of blighty!

 

Mute swans on the other hand are native to Europe, Asia and parts of Northern Africa and were introduced to the Americas and Australasia. Therefore, in the wild they are far less likely to encounter one another. When selecting a mate they will preferentially select a mate of the same species. However, if a given area is void of others swans of the same species, but does have other closely related wildfowl of the opposite sex they are perhaps more likely to pair up and attempt to breed. The black swan is a nearer relative to the mute swan than any other swan species.

 

Black swans have therefore been recorded as producing hybridised young with mute swans, producing large mottled grey and white offspring. Not to be confused with juvenile mute swans! In addition, both black and mute swans have also hybridised with tundra, whooper and trumpeter swans and even greylag, snow and Canada geese!

 

First generation wildfowl can produce viable offspring and this often leads to problems with correct identification. Where dominant wildfowl species hybridise with more passive species, this can lead to conservation threats as was seen with the native white-headed duck population following the introduction of ruddy ducks to the UK. 

 

Check out this discussion on our Community: https://community.rspb.org.uk/wildlife/f/wildlife-questions/7342/a-likely-pair/53975#53975

Where I work, there are herring gulls nesting on the roof. The employer had got men to remove the eggs and kick apart the nests. Is this legal? chevron-down

Sent in by Diane Main, Aberdeenshire. 30 June 2009

 

Gulls, like all UK wild bird species, are protected under the Wildlife and Countryside Act 1981. This makes it a criminal offence to kill, injure or take a gull; or to take, damage or destroy its nest whilst the nest is in use or being built. It is also a criminal offence to take or destroy their eggs.

 

However, there are exceptions to this and the law recognises that in some circumstances control may be necessary. As a result, the government issues a series of General Licenses which permit authorised persons to control certain species of gull for specific reasons. In Scotland, the reasons herring gulls can be controlled under a General License are 1) to preserve or protect public health and safety 2) to preserve air safety (e.g. near airports) or 3) to prevent serious damage to livestock, food for livestock or crops. If the reasons given are for anything other than these, then the people concerned would potentially be acting illegally.

 

Before a General License can be used for any of the above reasons, the person must be convinced that there is no other satisfactory solution to the problem. Alternative solutions that can be tried include deterrents such as spikes or wires (to prevent roosting and nesting) or audible/sonic deterrents.

 

Gulls being a 'nuisance' e.g. noise or damage to property are not legitimate reasons for control under the authority of a general license.

 

In most cases, culling gulls is avoiding the real issue - problems and conflicts between gulls and people have risen dramatically over the last 20 years, which coincides with the wider availability of fast food and waste. Herring gulls will eat almost anything of suitable size and texture, feeding on waste food in urban areas, waste from landfill sites, the deliberate feeding by the public and natural food such as fish, invertebrates, molluscs etc. The most effective control measures involve reducing the availability of food and deterring them from nest sites. However, this is not an instant solution, and requires planning and action well ahead of the nesting season. Because most gull-related problems are confined to the breeding period, and because gulls usually always return to the same breeding site each year, once access to a breeding area has been blocked and the area protected with deterrents, the gulls will move elsewhere.

 

Lethal control, including the destruction of eggs and nests, can be ineffective if used in isolation. Physical measures need to be put in place immediately to prevent re-nesting.

 

Our gulls
There are five main gull species that occur in towns, and of these only four have populations in excess of 80,000 pairs, but all qualify as species of conservation concern:

• the UK herring gull population has declined by more than 40% since 1970,

• the black-headed gull population has declined by around 40% in the UK since the mid 1980s,

• the common gull population has declined by more than one-third in the UK since the mid 1980s, and is declining elsewhere in Europe, especially in Scandinavia,

• the lesser black-backed gull occurs in internationally important numbers: one-third of the European population nests in the UK.

 

The black-headed gull and common gull can only be killed or taken under General License at certain aerodromes.

 

Three gull species, the yellow-legged, little and Mediterranean gull are fully protected and cannot be killed even under the terms of the General License. There is a danger that people who cannot distinguish between gull species may be killing some of these species and thereby causing further declines in their numbers.

 

If you believe that the control being carried out at your work place is for a reason other than those legitimate reasons for gull control listed above, this is a matter that should be referred to the police for investigation by a wildlife crime officer. You can do this yourself or we can help you if you need to remain anonymous.

Would the earwigs in my nestbox deter birds from nesting in it? chevron-down

Sent in by Maureen Watt, Ellon, Aberdeenshire. 12 March 2009

 

Earwigs (Forficula auricularia) is the common name given to the insect order Dermaptera. They are characterised by the membrane wings that fold underneath short leathery forewings - the literal translation of the order name is 'skin wings'.

 

They are attracted to cool, moist areas, such as leaf litter, soil, under bark or in hollow plant stems. They are generally nocturnal and spend their days resting; coming out at night to scavenge on decaying plant and animal matter, fungus and other insects.

 

Earwig bites, despite what some people claim, are quite harmless and never fatal because earwigs don’t secrete any poison. Though the earwigs' pincers (or cerci) are quite strong and the pinch may be a bit painful, there is no reason to worry about an earwig bite.

 

The urban myth that earwigs burrow into people's ears at night and lay eggs in their brains is also not true. Earwigs are not parasitic so it would not be typical behaviour, and a female would much rather lay her eggs under a damp, dark stone than in your ear! 

 

Earwigs could be considered a beneficial addition to a garden, especially as they prey on other insects. They can cause some damage in gardens as they chew plants, but on the other hand, they eat many plant pests and their eggs, such as aphids.

 

Birds will actually eat earwigs so having them in the box could be a good thing. They are full of protein and are a good source of energy. Attracting more birds into your garden will help to keep the number of earwigs down, along with other garden pests, such as slugs and snails.

 

For advice on how to attract birds and other beneficial wildlife to your garden you can take part in our Homes for Wildlife project.

I have a nestbox for blue tits. Could I put up one for robins nearby, or will they attack each other? chevron-down

Sent in by Debbie Ramsden, Surrey. 17 February 2009

 

Robins and blue tits are fiercely territorial against individuals from the same species. However, there should be little competition between these two species. There should be room for both these nestboxes in your garden.

 

Robins and blue tits have different nesting requirements. Blue tits prefer to nest in a small hole with a clear flightpath to the entrance. Robins usually choose a site low down in dense vegetation. They prefer open-fronted nestboxes.

 

These two species also have different foraging techniques, so there should be little competition for food. Robins are mainly ground feeders and will take worms and invertebrates from the soil. Blue tits prefer to feed off the ground and they take mainly seeds and nuts. Their diets do overlap in some areas though.

 

Robins do have a habit of attacking other species they compete with more closely, particularly those with red breasts. Stonechats, whinchats and redstarts are often chased away. Blue tits can compete with great, marsh and coal tits for nest sites and food. However, providing plenty of food and other resources will help to reduce any competition.

What percentage of birds don't manage to find a mate? chevron-down

Sent in by Chris Wayman, Alsager, Staffordshire. 6 February 2009

 

Good question. There is no definitive answer to this; the percentage is significant, but it varies greatly from one year to another, and from one species to another.

 

Before a garden bird can contemplate a mate, he needs a territory. Having found a suitable territory, he will then need to defend it against other males, at the same time as attract a mate. He does both jobs by singing. To another male, the song is a war chant - 'stay away, I am big and powerful, this is my patch' is the message. On the other hand, to a female the same song is the sweetest love song he hopes she cannot resist.

 

There are only so many territories that an area can hold, and there are inevitably males that fail to secure a territory. Similarly, there are females that fail to find an available male with a territory. There are always these surplus birds around, more on years when previous year's nesting success was high and lots of birds survived over winter, fewer on years when past weather has caused a population dip.

 

What happens to the unpaired birds?

So what do these birds do with their time? Birds have a very strong urge to obtain a territory and a mate, and to breed. The unmated birds spend a lot of their time in the leftover spaces between territories, where they do all the things that birds do outside the breeding season, without being harassed by territorial birds. Still, they do stray into occupied territories, sometimes deliberately to test the resolve of the territory holders, since they are always on lookout for any opportunity to gain a territory and have a chance to breed. Many of the quarrels you see between birds as you watch them in your garden during the spring and summer involve these interlopers.

 

Vacancies in territories can appear at any time as a result of predation by a cat or a sparrowhawk, collisions with a window or a passing car, other injuries or disease just to name a few. As soon as such a gap appears, an unmated bird is quick to fill the space. Inevitably, there are always birds that fail in their quest. They must bide their time and hope to survive to another, more successful, breeding season.

Are there birds in Britain that bury their eggs? chevron-down

Sent in by Judith Andrews, Birmingham. 7 July 2008

 

Lots of birds do nest on, or under, the ground across the UK, but no birds actually bury their eggs.

 

This rather puzzling occurrence may not have been the work of a bird. I would suspect that a fox has been in the garden.

 

The red fox is a cunning scavenger that will feed on a range of food items including birds, mammals, carrion, scraps and if it comes across a nest, eggs. If a fox is lucky enough to come across a deserted nest of a duck or pheasant for example, it will usually eat some of the eggs there and then. However it may also want to cache some of the food for a later date.

 

Foxes often hide food in places such as compost heaps or in soil where it is out of the way of other hungry animals and will temporarily delay certain forms of decomposition. When the fox gets hungry, it will return to the site and remove its hidden meal.

 

The eggs and young of ground nesting birds are therefore quite vulnerable to passing predators such as foxes. Birds such as waders, terns and mallards combat this by having very effective camouflage which blends in to the habitat that they choose for nesting.

 

Many seabirds have different strategies for predator evasion. Puffins and shearwaters usually nest in burrows and cracks in coastal rocks whilst kittiwakes, razorbills and gannets choose cliff ledges for their breeding sites which are mostly out of reach of even the most cunning fox.

Do hen harriers start incubating from the first egg laid? chevron-down

Sent in by Dean MacAskill, Dornoch. 16 June 2008

 

Most songbirds, waders, wildfowl and game birds won't start incubating until the last egg has been laid. This means all the chicks should develop and hatch at the same time. With birds such as ducks that leave the nest soon after hatching and head for cover, it is important all the chicks can leave together. However, birds of prey often start incubating when the first egg has been laid.

 

Hen harriers usually lay between four and six eggs sometimes up to eight. There is normally a gap of one to three days between each egg being laid. Each egg will be incubated for 29-31 days and the clutch for 29-39 days in total.

 

The female hen harrier will start incubating after the first to the fourth egg has been laid. If they incubate when the first egg has been laid then the chicks' development will be staggered. The oldest chick could be 10 days further along in its development than the youngest.

 

The larger chick would obviously have the advantage but if food is abundant then all chicks have a good chance of surviving. If food is difficult to find then the younger chicks, particularly in large broods are less likely to survive but the older chicks still could. This harsh but effective method ensures that only the chicks that can be reared to an acceptable level will survive. In some rather gruesome cases, the older chicks may eat their unfortunate younger siblings.

Would a male robin feed its mate, or could it be a youngster from an early brood? chevron-down

Sent in by Elizabeth Jones, Barton-on-Sea. 6 May 2008

 

Since robins start to lay eggs for their first clutch in late March, it is possible to have fledglings at this time of the year. However, a fledgling robin does not have a red breast - it will get this only as it moults in the late summer or autumn. If both birds you saw had a red breast, they would have been adults, and what you witnessed will have been courtship feeding, with the male feeding the female.

 

Courtship feeding occurs in many species of birds, and it has two main functions. At first, it is the bird equivalent of a box of chocolates or a bunch of flowers - a means for the male to woo the female and strengthen and maintain the pair bond. Later on, as the female is laying eggs, the food provided by the male can make up a significant proportion of her diet during a period when she needs extra energy for the egg production.

 

In robins, courtship feeding starts a couple of days before she lays the first egg, and continues through the incubation, which is by the female alone. With around 30-50 feeds per day, the male is making a significant commitment to his mate and the offspring already before the chicks hatch. After hatching, both parents will be fully occupied feeding their hungry young for the following two weeks. Since robins can have three broods in a season, courtship feeding can be seen well into the summer, and is a clear indication that the pair are in the early stages of nesting.

Why are bird eggs different colours? chevron-down

Sent in by Roy Codd, Basingstoke, Hampshire. 14 February 2008

 

In the same way that the colour of a bird’s plumage can vary from species to species, the colour of bird’s eggs can differ too.

 

These range from plain colours to a whole host of different coloured markings.

 

Birds that lay their eggs in the open or on the ground, such as the lapwing, rely on their eggs being well camouflaged. This camouflage takes the form of coloured spots or patterns, which blend into the surrounding ground cover.

 

Birds that lay their eggs in holes or anywhere where dark, such as a kingfisher, are likely to have eggs that are either white or pale blue and this helps the birds locate them.

 

The eggs of the great crested grebe can actually change colour during incubation. These eggs start off a bluish white colour and after being in contact with the water plant-based nest material, these eggs turn a brownish colour.

 

Despite the variations in bird egg colour, there are in fact only two pigments, which are responsible for bird egg colour. Oocyan, which derives from bile, is responsible for blue and green shades and Protoporphyrin, a blood derivative, is responsible for spots, patterns and some general colour.

Is it usual for 26 eggs to be in the nest of a mallard? chevron-down

Sent in by Mike Thompson, Cemaes Bay, Anglesey. 11 April 2008

 

Mallards normally choose to nest near water and ideally within well-covered vegetation.

 

However, artificial nest boxes, baskets and other man-made structures can also be used and some mallards have even been known to use flowerpots situated on high-rise flat balconies!

 

Nests are usually made of grass and other vegetation and are lined with soft down feathers. Mallards can lay a maximum of around 16-18 eggs, but a normal clutch is more likely to contain 10-12 eggs. These eggs will not all be laid at once and are normally laid within 1 to 2 day intervals. Once the clutch is complete, the female will then begin to incubate the eggs and this takes up to 28 days.

 

26 eggs in one nest, is mostly likely to be the work of two separate ducks, as you suggest. It is not entirely certain as to how this may have come about, but one possibility, may be that the original occupant either died or abandoned the nest as a result, of disturbance or threat of predation. Whilst mallards can sometimes nest as close as a metre to each other, they are not colonial in their nesting habits and this occurrence is likely to be result of an opportunistic female.

Do woodpeckers try to enlarge nesting box holes without any intention of using them? chevron-down

Sent in by John Norman, Wheldrake, near York. 17 March 2008

 

Of all of our native woodpeckers, the great spotted woodpecker is the mostly likely to readily take to a nestbox. This, like the many cavities that they may excavate in trees, can either be used for nesting and or roosting in.

 

Not all excavations made in trees are actually ever used and some woodpeckers rather than excavate their own will readily use existing holes. In addition to excavating nestholes, woodpeckers will also chisel away at wood in order to get to wood-boring insects as well as drumming on trunks and branches to advertise their presence.

 

Woodpeckers normally start to breed around April time and great spotted woodpeckers, if they choose to use one, will frequent a nestbox with a 50mm aperture.

 

Nesting and roosting is not the only reason why a woodpecker may show interest in a nestbox. Unfortunately, great spotted woodpeckers, like squirrels and cats will on occasion investigate the nestboxes of small bird species with a view to taking the young. In order to avoid this, a metal plate can be fitted around the entrance hole of a nestbox and this will help prevent the woodpecker from chiseling away at the hole in order to get at the contents.

Can all birds regurgitate food when feeding their young? chevron-down

Sent in by Craig Rot, Ireland. 18 May 2007

 

Not all birds can regurgitate food.

 

There are several main reasons for regurgitation and it is employed in a number of different ways.

 

The first example is in gulls and other birds that transport food over long distances. Many of the larger gulls forage over hundreds of kilometres and over several days, so it is impractical to carry fish around because they would be pirated by other gulls and skuas.

 

Some seabirds are able to spontaneously regurgitate, even as juveniles. Fulmars employ this as a defence when disturbed at the nest.

 

Terns also regurgitate fish but these are likely to have been locally caught and are not digested to any great extent. This is also a strategy to avoid piracy, although some species will not swallow the catch if foraging close to the nest.

 

The second example is finches and other seed-eating birds. Each species has a slightly different strategy in terms of how much regurgitated seed is provided to the young.

 

Surprisingly, many seed-eating species provide soft-bodied invertebrates as a more important element in the diet of the youngsters, but all provide some regurgitated seed as a way of passing on gut bacteria to help digestion of problematic chemicals such as cellulose.

 

Finally (although there are many more examples), swifts, swallows and martins produce a ball of insects called a bolus. Many of the individual food items are small and, as with the above examples, it would be impractical for the birds to return with these in their beaks, so they are stored until sufficient numbers have been collected.

 

The food is not always swallowed because the bolus can be formed in the crop and is not true regurgitation given the food is not necessarily mixed with digestive juices in every case.

Can I cut down a tree that blackbirds have started nesting in? chevron-down

Sent in by Brian Hood, Market Deeping, Peterborough. 2 March 2007

 

Under Section One of the Wildlife & Countryside Act (1981), it is an offence to intentionally damage or destroy the nest of any wild bird while it is in use or being built - which is also referred to as an 'active' nest. 

 

A nest is considered active as soon as the first twig, or other nesting material, has been added to the nest site. If you know that there is a nest being built or occupied, you would have to delay the work until after the blackbirds have bred.  

 

Blackbirds often have three broods. After laying, the eggs take 13-14 days to incubate. After that, the newly hatched nestlings will take a further 13-14 days to fledge and leave the nest. So, if each brood takes approximately one month to fledge and the pair have three broods, the nest will be deemed active for around three months.

 

If you are planning any tree cutting, hedge trimming or other garden maintenance, always check beforehand that there are no active nests present. If you see birds carrying nesting material or food items into a hedge, bush or tree, you can be pretty sure that there is a nest within. Remember also that certain species have been known to nest in every month of the year, so always check first!

 

If you see anyone potentially damaging or destroying a known nest, you should contact the Investigations Unit at the RSPB on 01767 680551 or report the incident online at https://www.rspb.org.uk/birds-and-wildlife/advice/how-to-report-crimes. You can of course remain anonymous.

Do starlings nest in boxes? chevron-down

Sent in by Stanley Morrow, Letchworth Garden City, Herts. 23 January 2008

 

Starlings are cavity nesters so will definitely use nestboxes. They prefer a box slightly larger than the one used by blue tits, with an entrance hole of 45mm.

 

Boxes for starlings can be placed on trees or, in a shady spot on a building. They don't mind company, so will nest quite close to one another. They regularly nest in roof spaces too and are not always welcome. Seldom causing damage, they can be rather noisy but for a very short period.

 

For several years they shared my house, nesting in a small opening on the chimney. They were noisy but very welcome. When the outside of my house was decorated, during January last year, the decorator, with the best of intentions, repaired this area blocking the hole. We quickly installed a nestbox as close to the site as possible and were delighted when they took to it immediately and raised two lots of young. I am looking forward to their return and we have already had reports of starlings and other species, inspecting nestboxes ready for the breeding season.

 

If planning house maintenance, do be aware that several species of birds, including house sparrows, house martins and starlings may be nesting in the roof space. If the nest is not active, but the site needs to be removed, or the entrance blocked, it will be very beneficial if a nestbox can be provided. 

 

Loss of suitable nest sites, for starlings and house sparrows, has contributed to a massive decline in their population. It is illegal to to anything to an active nest. For further advice please call Wildlife Enquiries on, 01767 693690.

Do the various species of birds nest at specified heights from ground level? chevron-down

Sent in by Frank Newcombe, Somerset. 6 July 2007

 

Even closely-related species of bird nest at different heights above ground level.

 

For example, common whitethroats typically nest at less than 1ft, and rarely higher than 2ft, from the ground, while lesser whitethroats nest above 2ft from the ground. Another example is blackcaps and garden warblers, with the former nesting higher.

 

The type of vegetation is likely to be a major factor, because these differences in height are not so easy to see where vegetation is less varied in other parts of the birds' ranges. Robins, blackbirds and wrens often choose sites close to the ground because denser cover is more likely to be found at this level.

 

Habitat is also the determining factor in the nesting heights of birds in seabird colonies. These range from (top to bottom) gulls nesting among grass at cliff top, through puffins and fulmars at the edges of the grass, guillemots and razorbills on bare ledges to shags among boulders close to the high tide line.

 

The height of artificial nest boxes can strongly influence the birds that are attracted. House sparrows prefer the highest possible site. This usually means roof eaves, unless there is cover of plants like ivy lower down on a wall.

 

Most studies suggest that great tits prefer to nest lower than blue tits when it comes to natural nest sites. This can be reversed with nest boxes, although blue tits have been known to occupy sparrow terraces high on a house wall.

Do skylarks sing at night or maybe before the sun rises? chevron-down

Sent in by Mini, India. 25 May 2007

 

During the breeding season, skylarks will start to sing from well before dawn and continue until well after dusk. The function of the song at this time of year is to attract a mate, so singing in the dark conveys the same signal to the female as singing during the day. It is the length and duration of these song-flights which attracts the female.

 

In terms of energy expenditure, the song-flight of the skylark is one of the most costly: flight involves energy expenditure, as does the production of the song. It is believed that this expensive energy cost sends an honest signal to the female of the males fitness and sexual availability.

 

At other times of year, skylarks are not particularly early risers compared to other families of bird such as the thrushes and finches. They will also sing during these non-breeding periods as an anti-predator deterrent. It is thought that by singing, the skylark is indicating to a potential predator that it is strong and in a healthy condition.

I have a blackbird nest in my wildly overgrown hedge. The babies have hatched, but how do I know if this is the blackbirds' first brood? chevron-down

Sent in by Julie Bush, Leeds. 8 June 2007

 

We do not recommend cutting or removing hedges or trees between the months of March and August.

 

Light pruning to neaten up a hedge from straggly shoots should not be damaging to nesting birds but the use of power tools and vigorous cutting and can be very destructive. If any work takes place it is vital to check for nesting birds before the work takes place. Nesting birds are often difficult to find even by the most observant of gardener so it is best to err on the side of caution. Certainly if you see a nest or a bird taking food into the hedge, I would leave well alone.

 

The best time cut a hedge is generally autumn or if it is a berry bearing species, early spring but no matter when you do it, always check first.

 

Blackbirds can start breeding as early as February if the weather is favourable. It is normal for a blackbird to have up to three broods in a season, this activity can go on until late summer, sometimes even into autumn. Other species like the robin, song thrush, dunnock and wren are also common hedge nesting birds among many others that may be vulnerable from hedge cutting.

 

It is also worth highlighting the fact that gardens that are neat and tidy are often not the best gardens for wildlife. Leaving wild patches and cutting hedges and lawns less often will be beneficial to wildlife. Gardens are vital for wildlife in built up areas as they may be the only suitable habitats for birds, insects and mammals. By leaving hedges to grow through the summer, planting wildflowers, creating a pond and a log pile it is likely your garden will become an urban oasis.

 

Please see the pages on the website on creating a wildlife garden.

Is it possible for two nestboxes that are close together to be occupied by blue tits? chevron-down

Sent in by Terry Gleeson, Swansea. 26 November 2007

 

It is unusual for two pairs of blue tits to nest close to one other in gardens, unless you live in a neighbourhood where gardens are large and contain a good supply of mature trees, preferably oaks.

 

Tree density in gardens is far lower than that in a wood and gardeners tend to choose ornamental tree species, which support a comparatively poor insect crop. Consequently, garden blue tits need to spread themselves out into larger territories in order to secure adequate food supplies for the breeding season. Although it  is unlikely that two nesting boxes would be occupied by blue tits in a normal suburban back garden, it is possible to have one box occupied in the front garden and a second one in the back garden.

 

Birds often view rows of houses as dividing lines between pieces of suitable habitat, and divide their territories accordingly. If coal tits regularly visit your garden, it may be possible to encourage them to take up residence in a nestbox, although being shyer, they prefer a quiet corner rather than a box close to the house. Since they also need a 25mm entrance hole, it is possible to have both a pair of coal tits and a pair of blue tits nesting in your garden.

 

Blue tits are territorial against other blue tits only, and so any one area can hold several pairs of nesting birds of different species.

 

Although blue tits and great tits are not territorial against each other, they can fight over nesting sites. If you witness this in your garden, fixing a second box a discrete distance from the first one may well result in two happy families. Make sure that one box has 25mm entrance and the other is 28mm or larger to discourage them continuing to squabble over the same box.

s a peregrine likely to use the same nesting spot every year? chevron-down

Sent in by Alistair McCabe, Dundee. 13 April 2007

 

The breeding season for peregrine falcons starts from March onwards and nest locations can vary from natural sites such as cliff ledges or rocky outcrops to man-made structures such as building ledges and the occasional disused chimney stack. 

 

Ultimately the nest location will depend on the resources available, food for example, which for peregrine falcons consists of small- to medium-sized birds.

 

The nest itself will form a simple hollow scrape, in which no nesting material is used. A scrape is usually made by the female bird using her legs and chest.

 

Within a pair’s territory, there may in fact be more than one nest site and where food resource and suitable climate is agreeable it is most likely that the pair will remain within the same general area and may certainly use the same nesting territory.

 

Established pairs of peregrine falcons, which have existing nesting territories will normally remain together outside of the breeding season. The pair may remain together from one season to the next and where pairs are resident, this bond may be life-long. 

 

Peregrine falcons often remain in a family unit until the autumn and established pairs have been known to hunt together during the winter although the pairs will break up when times are hard with individual birds wandering widely, as the name suggests.

When can I paint my house without affecting the house martins nesting there? chevron-down

Sent in by Jim Waugh, Mouswald, Dumfries. 29 June 2007

 

The nests of house martins are a welcome, additional feature of many properties throughout the UK, although they are only occupied for a few months each year. 

 

Attractive blue-black, black and white birds, each spring house martins travel thousands of miles to enjoy our hospitality. They brighten up our skies as they swoop around catching flying insects, their main food, chattering to one another constantly. 

 

They arrive in April and May and quickly reclaim and repair their nests or build new ones. During their breeding period they will often rear two lots of young, sometimes three. 

 

House martins usually leave for their long flight back to Africa during September but, if they do attempt a late brood, their nests may still be in use until early October.

 

Once the birds have flown and the nests are no longer in use then they can be removed. House martins are now amber listed as birds of conservation concern due to their population decline, so we are grateful to you for thinking about them. 

 

To help them next year you may consider installing one or two artificial nests once the decorating is completed. 

Is there an easy way to stop starlings nesting in our loft and how much damage would they do if they were left to get on with it? chevron-down

Sent in by Ami Johnson, Somerset. 12 March 2007

 

Starlings are inquisitive and adaptable birds. They nest in holes and crevices in a variety of man-made and natural structures. Despite this, they are in serious decline, with the UK breeding population having declined by 65% over the last 30 years. This decline qualifies the starling as a 'red-listed' species, that is, of the highest conservation priority.

 

At this time of year, starlings will be investigating any crevices and holes in buildings for a suitable place to breed. Breeding usually starts in mid-April, so it is possible that they are only roosting in the roofspace in the evenings and leaving the following morning to feed.

 

Starlings are protected under the Wildlife and Countryside Act 1981, which makes it illegal to intentionally kill, injure or take a starling, or to take, damage or destroy an active nest or its contents. Preventing the birds from gaining access to their nests may also be viewed as illegal by the courts. It is therefore important to check for active nests before any repairs to roofs and soffits are carried out during the breeding season.

 

It would be a pity to deny these charming birds access to a suitable nest site, so when carrying out repairs or building from new, consider putting a nest box behind fascia and soffits that are not positioned directly over main living areas. This confines the birds to one area and prevents them accessing the whole roof space. 

If I put up three nestboxes in my garden, will they all be occupied? chevron-down

Sent in by Paul Howard, Leyland, Lancashire. 17 November 2006

 

The number of birds that can breed in an area depends on the available resources. A wildlife-friendly garden with plenty of nest sites and abundance of food would support more breeding birds.

 

Competition is most likely to occur between the blue tits and great tits. Both species prefer to nest in holes with clear flightpaths and have very similar diets.

 

Great tits will tend to dominate blue tits because they are larger. Ensure the nestbox for the blue tits only has a 25 mm hole so it will be unsuitable for a great tit. You can then provide a great tit nestbox with a 28 mm hole elsewhere. Putting the nestboxes as far apart as possible should help to avoid any conflicts. 

 

Mealworms can be a valuable food source in the breeding season. These can be put out to supplement the naturally occurring insects in your garden and should help reduce the competition.

 

Robins rarely show signs of aggression towards other species. They prefer to nest low down in dense vegetation in an open-fronted box, so would not compete with the tits for nest sites.

 

Reports of aggressive behaviour by robins towards other species are outnumbered by reports of robins actually feeding the young of other birds. They have very strong parental instincts and the sight of a baby bird gaping is too much for them to resist. Blackbirds, song thrushes, great tits and blue tits have all benefited.

We can hear birds singing at night (2am) in trees adjacent to the house in mid-December. Why? chevron-down

Sent in by Chris Marsden, Leyland, Lancs. 22 December 2006

 

The main purpose of singing is to attract a mate and defend a territory. Robins are one of the few birds that hold a territory throughout the winter so continue to sing when the majority of other birds have stopped. 

 

Robins are often one of the first birds to start singing in the morning and the last to finish in the evening so are used to being active in low light conditions. In places where there are street lamps or other artificial light sources, robins can be triggered to start singing because it does not get completely dark. Other disturbances, like a loud noise or movement, can also start birds singing in the night.

 

Some birds in Britain regularly sing in the night. The nightingale is the bird that many people would associate with nighttime singing but corncrakes and nightjars do as well. However, these birds are only summer visitors to Britain and should now be wintering in Africa.

Clearing my asparagus beds I came across a half-buried, white, chicken-sized egg. How did it get there? chevron-down

Sent in by Sharman Flindall. 20 January 2012

 

Sharman asks: 'Clearing the dead folliage of my asparagus bed I came across a white egg, about the size of a chicken egg. It was half buried. What could have laid it and how did it get there?'

 

The size and colour of this egg suggests that it was laid by a duck, most likely a mallard. Though mallard eggs are usually pale blue-green, this can vary and an almost white one would not be unheard of.

 

Though pigeons can also breed this time of year, their eggs (though white) are much smaller than a chicken egg. The breeding season for mallards is usually around March onwards. It can, however, potentially occur any time from February to late Autumn and maybe even earlier if the weather is mild. Because of the recent mild weather many birds have begun to breed earlier than usual.

 

Mallard nests are usually built by the female and form a hollow lined with grass, leaves, down and feathers into which she will lay around 10-12 eggs. These eggs are then incubated for around 28 days.

 

Hidden by cover, mallards regularly nest on the ground, making their contents easy prey for an opportunistic predators, such as foxes. I suspect this egg has been removed from the nest by a fox which has subsequently buried it for later retrieval. Such caching is not unusual amongst mammals, grey squirrels, for example, are notorious in burying nuts for when food is less readily available. Fox caches are, for the most part, temporary and may last a night or two at most, with eggs being a common cached foodstuff. Fox caches are rarely dug very deep and in urban areas can be found in flowerbeds or plant pots!

I have a chaffinch in my garden that is driving me absolutely nuts! It is calling non-stop and it goes on hour after hour, from dawn until dark. Why? And when can I expect it to stop? chevron-down

Sent in by Joanne Hunt, Huntingdon. 13 July 2012

 

From what you have described, this repetitive and monotonous song is the chaffinch 'rain' call, and although it is far from the most melodic part of this bird's repertoire, some consider it to foretell rain, though this is highly disputable.

 

Occurring in long series, this call varies from region to region, thus giving rise to distinct local dialects. Despite the variation, this call often takes the form of a repetitive 'huit', 'hreet' or 'breeze'. Though this call can occur spontaneously, it is usually heard within the context of the breeding season or as an alarm call. The usual alarm call of a Chaffinch normally takes the form of a high-pitched 'seeee'.

 

Chaffinch breeding season usually begins around late April, but can occur in mid-July. Chaffinches build their compact cup-shaped nests in the forks of trees or hedges, and once complete, they will have one brood of around 4-5 eggs, which will be incubated for 11-13 days by the female.

 

Once the young have hatched, they fledge and leave the nest after a further 13-14 days. If the call behaviour of this particular individual is linked to the breeding season, then it is unlikely that this call will continue indefinitely.

 

It is worth bearing in mind that in addition to the rain call, chaffinches are capable of producing some highly musical songs that end with a flourish, listen out for the lyrical ‘chip-chip-chip-tell-tell-cherry-erry-erry-tissi-cheweo’ or ‘tupe, tupe’. Chaffinches, and especially the males, have unmistakable plumage. You have only to marvel at their grey-blue crown, pinky-brown cheeks and chest and striking white wing stripes.

Is there a type of vent that can be fitted into our garage roof to give swallows access? We've had to leave the door or window open for each or the last 3 summers? chevron-down

Sent in by Janet Howell, Staffordshire. 14 February 2013

 

Swallows choose to nest inside buildings that have open access so barns, stables, sheds, car ports and even porches all provide suitable protection for their fragile mud nests. 

 

As long as the swallow can get in and out throughout its stay in the UK, any such structure close to open ground where they can feed is a potential nesting site. 

 

Swallows make their epic journeys back into the UK at the start of the year with the trailblazers making our shores throughout March. They will often head straight back to their natal areas and seek out nesting sites from previous years. 

 

In order to get in and out of a building swallows need a gap of at least the size of a standard housebrick. If you would rather not leave a door or window open through the summer but could create such a gap then the swallow may be able to complete another year of nesting inside your garage. Ideally try to create the gap as close to previous entrances as possible.

 

A recent suggestion that a supporter kindly shared with us is to create an externally mounted swallow nesting structure. A simple rectangular box about the size of a standard tawny owl nestbox but with an open base and nothing inside but a shelf, mounted on the side of a barn or garage for example close to the areas where swallows have nested previously can provide them with an alternative weather proof structure if they cannot be permitted access into buildings.

 

One thing to be aware of is that once a swallow has arrived and starts nest building, they cannot be excluded from the site whilst they have an active nest. The swallow and it’s nest, eggs and chicks are afforded full legal protection under the Wildlife and Countryside Act 1981 throughout the period when that nest is active.

We have a birds nest in the garden constructed from moss and lined soley with black down feathers, with an entry hole at the top near to the branch. What is it? chevron-down

Sent in by: Ken Carter from North Lincolnshire. 31 October 2013

 

The nest you describe belongs to a long-tailed tit. Such a privilege to have them nesting in your garden, and such a delight to be able to see a nest close-up! 

 

Long-tailed tit nests must be the cosiest nests made by any bird. They are made of moss, woven together with cobwebs and hair, and camouflaged on the outside with lichen. The lining is always small feathers - anywhere between 1,000 and 2,000 of them! It can take the pair up to a month to complete their masterpiece. 

 

One special thing about these nests is that they stretch to accommodate the growing brood, and so always stay snug and just the right size even when there are ten fully grown young and a parent inside. There is no spare room inside the nest, as you can imagine, so what do they do with their long tails? When the female sits in the nest incubating the eggs or brooding small young, her tail is bent over by the side of her body. She spends such a long time couped up like this that her tail becomes temporarily bent even when she is having a stretch outside. So when you see a long-tailed tit with a bent tail, you can be sure that it is a nesting female.

Do blackbirds mimic human whistling? chevron-down

Sent in by: Brian Hill, Stonehill, Gloucestershire. 

 

Blackbirds are a common garden visitor and are without doubt, a highly vocal species capable of making a wide variety of calls and songs. During the breeding season, the song we are most familiar with is the rich fluid song made up of flute-like phrases or notes. Chances are, we may also hear a disturbed or agitated Blackbird emit a loud ‘tchook-tchook-tchook’ or ‘chink, chink, chink’ call.

 

The song repertoire of an adult blackbird is highly complex and is down to a bird’s individual inventive ability along with the species high capacity for learning. The variety within a bird’s song is also dependent on its age, its stage in the breeding season and the time of year. Song learning occurs throughout a blackbird’s life and reciprocal learning between neighbours can create local dialects.

 

A blackbirds' song is not just made up of repeated learned phrases from other blackbirds, blackbirds like a great many other birds, are superb mimics. Studies have shown that they are not only able to mimic other birds, but also domestic cats, as well as a variety of mechanical sounds. Blackbirds have even been recorded making the sound of a reversing lorry! It has also been noted that blackbirds can imitate human whistles either as a singular note or phrase. A bird may hear someone whistle and may replicate this sound in their song as it develops. Starlings are also well-known mimics and can do a passable imitation of a tawny owl as well as the sound of a spray can being shaken.

What is the average length of time of the dawn chorus and is there a UK record for the earliest chorus? chevron-down

Sent in by Stephen Gawen John Sellick, Enfield.

 

Unfortunately, it is not all that clear cut. This confusion is due to nocturnal songsters, usually robins, that regularly sing throughout the night. 

 

Robins can forage in dim light so will often be active after dark. They are territorial all year round, not just during the breeding period, and will regularly be heard in full song at night. This can be triggered by bright, artificial lighting but this is not always the case. 

 

So, it is hardly surprising to note that robins are considered to be first bird to be heard in the dawn chorus. The lone chorister for a while but soon joined by song thrush and blackbird, wren, dunnock and great tits with house sparrows and many finches bringing up the rear. 

 

Dawn is probably the most tranquil time of the day so a great time for birds to sing to claim territories and mates. 4am is the average time for the dawn chorus to begin in early summer but some birds will be heard much earlier. Often it is still dark and not great for foraging so, what's a bird to do? Burst into song is the answer and aren't we glad that they do? 

 

It makes an amazing, joyful sound for us on a spring morning but, for the birds, it is full of purpose and ambition.