Linda’s Answers to Rosemary’s Questions

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Do all birds lay blank eggs like a chicken? Eggs changing colour??

Many birds have speckled and coloured eggs. The specific colour/marking is created in the uterus in the reproductive tract. Pigmentation is laid down as the egg is turned. It then gets a hardening layer before being laid. I’m not sure where the ‘changing colour’ question comes in but some species i.e. the guillemot have eggs that are individually recognisable by their markings. Perhaps the person who wrote that question was thinking about cuckoos. They lay an egg in the nest of another bird and produce eggs that look just like those of the host bird (reed warbler; meadow pipit etc). Each female cuckoo will produce eggs to look like one species only – she can’t change the appearance of her eggs but different cuckoos will predate different species.

How do birds sit on high voltage cable without getting electrocuted?

Watch this video which explains it well https://www.youtube.com/watch?v=rN3QhtnlCSw

Birds move very fast to get prey. How fast do birds fly when they migrate? Which is faster, birds or insects? How fast does a peregrine falcon fly?

A peregrine falcon (a bird found in Leeds city centre) can soar to great heights so that it can fold its wings back and drop at around 200 miles per hour to kill a bird in flight (the fastest of any bird). In level flight it reaches 68 miles per hour. This is probably the same as a swift. Other than that, the fastest migration flight hasn’t yet been recorded. Technology is allowing us to gather this data as it develops and we can track smaller and smaller birds. Re birds v insects, i think birds are faster but at this stage, no-one knows the answer to that. Perhaps a large dragonfly might be able to challenge a swift.

Can birds smell?

Have a look at this article by Tim Birkhead https://www.bto.org/sites/default/files/u23/downloads/publications/bird-table/BT69_LR_12-13.pdf

Do eagles have unusually keen sight? How do owls see in the dark?

Yes, eagles and many other birds of prey are able to see 4 to 8 times better than humans. This is made possible by their extra large eyes (about the same as the size as our eyes in a very much reduced skull size) and highly developed dual focusing points on the retina. Owls see better in the dark because they have more light sensitive rod cells and fewer cone cells which process colour. This enables them to focus more on movement. One thing that helps this with more nocturnal owls is a wide facial disc. This funnels the sound towards the ears. Some owls have one ear lower than the other giving them the ability to hear in 3 dimensions. The slight difference in which sound reaches each ear allows the owl to determine the distance and height of the noise from the ground.

When it rains, where do birds go? Why do birds always face the same direction?

Most birds’ feathers are waterproof, made so by applying oil from their preen gland when taking care of their feathers (the preen gland is at the base of the body where the tail begins). Birds are not bothered by light rain, in fact, as water is needed for good feather maintenance, the utilise a small amount of rain and preen their feathers (a bit like having a shower). During heavy rain, they usually either sit in a tree or on the ground to conserve their energy. Wind and rain is more dangerous to them and can damage their feathers. This is when birds are seen facing the same direction. They face into the wind so that their feathers are not damaged. Waterbirds are not bothered by rain at all as their feathers are highly waterproofed. They can still get damaged by wind though so you may see them facing the same direction in windy weather.

How are migratory birds important to man?

In the past, migratory seabirds on cliffs were important as people used to harvest eggs and adults to eat and feathers to fill quilts and pillows. This still happens in some areas of the world but generally all nesting birds are protected by law. Migratory birds are hunted for sport both in the spring and autumn in some parts of the world, often illegally, but there are campaigns to get this stopped in Europe. It is legal to hunt overwintering wildfowl with a licence during certain months of the year and this is done for sport. By far the biggest importance now is ecotourism. Many areas rely on the income provided by birdwatchers while travelling to see particular species (puffins, gannets, nesting eagles, osprey etc). One aspect not often thought about but equally important is how the seasonality of birdwatching affects our mental health and wellbeing. The arrival of the first swallows, the first singing chiffchaff etc.

Does the temperature affect migration?

Yes but more accurately, it’s the weather direction that affects them. In order for birds to migrate in the spring, they need southerly winds to help them on their way. If the weather is coming from the north or the east, it is harder to migrate and it brings colder temperatures, therefore no insects will thrive. If birds arrive in the spring on southerly winds and then it turns northerly and cold, birds will struggle to feed and rear their young because of the lack of insects. Insect development is temperature dependent, for birds it is daylength that drives their hormonal system and breeding condition. In autumn, birds wait for northerly winds to help them fly south for the winter. Birds that spend the winter with us come from the arctic, Greenland, Iceland or Scandinavia. They need northerly and easterly winds to help them get to us. The flee from the cold winter temperatures in these areas and travel to the UK for the winter where it is relatively warmer.

Is it against the law to move a birds nest?

Yes. It is against the Wildlife and Countryside Act (1981). It’s an offence to deliberately take, damage or destroy the nest of any wild bird (or their eggs) while it is in use or being built. It is also an offence to disturb breeding birds. The most notable change in recent behaviour is by photographers. Many people are obsessed with taking bird photos but have no idea about a bird’s life cycle or bird behaviour so they are unable to recognise when their actions are upsetting nesting birds.

Are birds who can’t fly like penguins and kiwis?

(not sure what this means) Generally birds that no longer fly have developed other specialisms like being excellent swimmers or they are sedentary and have no need to fly.

What will keep birds away?

(Not sure what was meant by this)Farmers use scarecrows to keep birds from recently planted fields and bird scares (compressed air creating a gunshot sound) are also used. Trapping is done on the continent in lots of horrific ways such as lime traps and snares. Birds of prey are illegally shot on grouse moors to stop them eating grouse. Nets are used around orchards to stop birds from eating fruit and buds.  

What plants are best for wildlife?

Berry bearing shrubs and trees (hawthorn, cotoneaster, rowan, elder etc are good for overwintering birds).

Do different colour feeders attract different birds?

Yes. There was a study by CJ Wildbird foods that showed birds prefer different coloured feeders at different times of year. Certainly, my burnt orange feeder is unpopular in my garden. I’m attempting to get a copy of the research document.

Bird identification and sightings: Struggling to identify a bird I can’t recognise.

It can be difficult for beginners to find birds in bird books. Understanding the order of birds found in a good bird book will help with this. All birds with specialisms (wildfowl, Birds of prey, seabirds, waders etc) are towards the front. Small, perching birds comprise the last third of the book. Understanding shape, beak size, characteristics of movement, habitat, time of year etc will also help. This takes time and some focused learning.

When is it safe to cut your hedge? How long does it take baby birds to fledge?

It’s usually safe to cut your hedge from the end of July to the beginning of March. This is outside the breeding season but your hedge will be used for roosting at night in the winter. All birds should have fledged by this time. The maximum brood rearing time of small hedgerow birds is roughly 20 days for eggs to be incubated and another 20 days to fledge. Larger birds take much longer.

Do skylarks sing to attract insects?

No, all birds sing to attract a mate and proclaim their territory. Most birds only sing during the breeding season but some, such as the robin, hold a territory during the winter months.

Why do birds have territories?

Birds hold territories to ensure that they have enough food to take them through the breeding season. They find a suitable spot, with the right habitat, that contains the food they need to sustain them and their young. Some birds hold territories during the winter.

Why bird attack and fly into windows and how to stop them?

Sometimes birds can be seen flying up to windows and car wing mirrors repeatedly. This is because they can see their reflection and they think it’s another bird. This isn’t very good for the bird and distracts them from breeding successfully. It’s probably the result of having too high levels of testosterone. More often, birds will accidentally fly into windows. This often happens when there is a window at both sides of the house and a bird thinks it can fly through. At other times the reflection can cause confusion. Many times this can be fatal but often birds are stunned for a while then recover as long as they’re not predated while unconscious.

How long does a bird live?

Most small birds die before they reach a year old and only the fittest make it to breed. It’s impossible to get an accurate idea of longevity for each species. The information we have is from ringed birds that are caught again. From this we know that the longest known blackbird survived 19 years; osprey 50 years; Manx shearwater 65 years.  Generally, The larger the bird the longer it will live.

Can birds speak in phrases and warn each other of danger?

Birds use a diverse range of calls for different purposes. There are special calls to say a bird of prey is close by.

Which bird is famous as a collector?

The red kite steals objects to place in its nest. So far these have included flags, underwear, handbags, magazine pages, lottery tickets and tea towels. Also crow species such as the magpie and the jackdaw are known to steal objects for their nest.

 

These answers were given to us by Linda Jenkinson www.startbirding.co.uk

THANK YOU!!

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