Birds are truly beautiful creatures, they are also fascinating and all around us, roosting and nesting on our buildings and feeding in our gardens and refuse dumps, they are easy to find and fun to observe. Birds are probably the most beloved group of wild animals on the planet. Their ubiquitous presence, colorful form, intelligent actions and cheeky mannerisms endear them to us all and they are easy to love.
There are about 9 703 species of birds divided up into 23 orders, 142 families. Birds can be found on all major landmasses from the poles to the tropics as well as in or over all our seas and oceans and their accompanying islands. The total number of birds on the planet is very difficult to estimate because their populations fluctuate seasonally, but scientists have suggested that there may be between 100,000 and 200,000 million adult or near adult birds on the planet at any one time. Of these the most common or populous wild bird in the world is the Red-billed Quelea from south of the Sahara in Africa. These birds are so prolific that they are serious pests of grain and millions are killed at roost sites every year in a vain attempt to control their numbers.
The most common bird in the world is the Red Jungle fowl most regularly seen as the common domestic chicken. The most widespread commonly seen wild bird in the world is probably the European House Sparrow which has been transported all over the world by European settlers and can now be found on 2/3 of the land masses of the world including New Zealand, Australia, N. America, India and of course Europe. There are 3 possible ways of measuring largest in birds; heaviest, tallest and or longest wingspan. The heaviest bird ever was probably the extinct Dromornis stirtoni from Australia. This flightless giant lived between 1 and 15 million years ago and probably stood nearly 3m/10ft tall and weighed in at a massive 500kg/1100lb. The tallest bird ever was, as far as we know, Dinornus maximus, a Giant Moa from New Zealand. Another extinct bird, this time from S. America, has the record for largest flying bird and longest wingspan. The Giant Teratorn had a wingspan of at least 6M/19.5ft and could possibly have been as large as 7.5m/25ft.
Whereas the smallest bird in the world is generally agreed to be the Bee Hummingbird from Cuba, which weighs a mere 1.6g, or 0.056oz. Shortest wings and body length are not really appropriate measurements because they are disproportionately affected by whether or not the bird is flightless or not and its beak length respectively. Another major contender for smallest bird is the Little Woodstar from S. America. Both these tiny miracles of life fly very competently. The smallest flightless bird is the Inaccessible Island Rail. Reaching a mere 12.5cm/5inches in length and weighing 35g/1.45oz this little beauty can only be found in the southern Atlantic Tristan da Cunha Islands.
One of the most notable things about just about any bird population is that some of the birds are only present for some of the time. Between 1500 and 4000 species of birds migrate. Some birds travel south in some winters but not others. This is not migration, but dispersal resulting from a population boom. These population booms can occur regularly, i.e. every 4 or 10 years perhaps, but there is no return in the spring. Destruction or loss of food resources can also cause the irregular eruptions of birds to new habitats.
Seasonal migration is a major factor in the life of many birds. In some cases this migration is very obvious and involves huge distances but at other times it is much more subtle. In the UK most people know that Swallows, Swifts and many small passerines such as Wood Warblers and Redstarts are migratory birds. They are present in the summer, but fly south along with many other species to warmer climes for winter. Similarly, many ducks and geese are only present in the UK during winter while they return north to the near arctic in summer to breed. What is less well known is that a number of our more regular birds are migrants as well. Birds that we see all year such as Robins and Starlings either leave or come to Britain during the winter. For some of these species, birds move south a certain degree over their whole range so that though my local birds have left and gone south their more northern cousins have also moved south and arrived. The overall effect can be that to a cursory observation, the population is sedentary when in fact it is quite dynamic. A further complication to this picture is that in some cases only part of the population is migratory.
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Lily Smith is the owner of Online Mall of Information
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