The FAA has an FAQ on bird strikes and other wildlife hazards, which includes a (broken) link to their Wildlife Hazard Management at Airports - A Manual for Airport Personnel document .
Chapter 9 is called "WILDLIFE CONTROL STRATEGIES AND TECHNIQUES AT AIRPORTS" and includes the following techniques: Change flight schedules Modify the birds' habitat (food, cover, water)
Physically exclude the animals (not so easy with birds)
Repel the birds with vehicles, chemicals, sound, visual objects (flags, scarecrows, fake dead animals, lasers)
Repel the birds with trained falcons or dogs Shoot
nonlethal projectiles at the birds Trap, remove and release the birds at a different location Kill the birds with poison or other means
The document summarizes the various techniques like this: Habitat modifications to minimize food, cover, and water and physical barriers to exclude wildlife are the foundations of wildlife hazard management programs for airports.
In addition, an integrated array of repellent techniques is necessary to disrupt normal behavior and to stress hazardous wildlife that attempt to use the airport.
These repellent techniques must be used judiciously and backed by real threats to minimize habituation.
To this end, lethal control of selected individuals of common species is sometimes necessary to reinforce repellent actions.
aviation.stackexchange.com/users/62/Pondlife
about.com has a good article which lists the many methods that are used to scare birds away from airports.
It includes: Modify the habitat:
Remove sources of food, such as seed-bearing plants, use insecticides to eliminate insects as a food source, remove bushes and plants that can be used for nesting
The use of visual devices (lasers) or audio (sonic cannons, recordings) to scare away birds Trained falcons, dogs, or other predators to make the airport inhospitable to birds.
Another source: Birds at Airports - Internet Center for Wildlife Damage Management
(Image Source:
WikiMedia Commons - Author: Bluescan sv.wiki )
aviation.stackexchange.com/users/572/SentryRaven
On a visit to Blackpool Airport control tower a few years ago, they mentioned that they flew a hawk/falcon (not sure which) every day to deter birds
aviation.stackexchange.com/users/6812/Dave45
The airport authorities use a number of techniques to manage the hazard of bird strike in and near airports.
These include, Elimination of bird habitats-
Birds usually come to the airport area due to the availability of food sources.
Denial of food to birds by eliminating the sources (like landfills, garbage, crops, dumps etc) will reduce the chance of birdstirke by eliminating the source.
It also helps to keep the airport and surrounding areas unattractive to birds (for example, by eliminating water stagnation, vegetation cover etc) as it prevents the birds from nesting there.
Scaring them away-
A number of airports use a number of bird repellents like pyrotechnics, cannons (mostly just prior to aircraft approach to prevent bird habituation), chemical repellents etc.
In some cases, specially trained animals (like falcons, dogs etc) have been used to scare away the birds or they are trapped.
In some cases, the flight schedule can be altered if bird movement is expected in the area (for example, if the airport is on a bird migration route).
The problem can be solved by simply killing the birds in the area, though this drastic step is usually not implemented except in the most extreme cases.
In general, the nesting sites of birds are destroyed to prevent them from staying permanently near the airport.
Usually, a combination of above methods is used to manage the birds.
The only procedure available for flight crews is to either delay the flight (or land in alternate runway if its available) in case birds are detected over an area.
This however, is dependent on a number of variables like fuel availability, flight schedule etc.
There are some radar systems under development that could detect birds; however, these have not reached operational stage yet.
aviation.stackexchange.com/users/9731/aeroalias
Trap, kill, harass, or deprive them of food and shelter.
The number of bird strikes at my airport has been reduced dramatically by consistently harassing the birds to the point where the birds eventually adapt and learn.
aviation.stackexchange.com/users/17647/Almighty 
All the correct information has been added except one point.
The engines nose spinners have a design painted on them.
Once the engines are running the design is suppose to look like the eye of a bird of pray to scare off birds in flight.
Does it work
I can not say
but they claim it does.
aviation.stackexchange.com/users/13697/user13697
I know bird strikes are a major issue for many airports, and that measures are taken to keep birds away. There are some obvious things airports can do like not to have any stray garbage, food, etc. in the open, but I'm sure other less obvious methods are also used.  What exactly are some of the widely used techniques to keep birds away from airports?
What are the ways to keep the birds away from airfields?
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<safety><airport><birds>
aviation.stackexchange.com/questions/11760
aviation.stackexchange.com/users/5694/NitinG
A number of approaches are used by airports to keep birds away. These range from using animals and birds of prey to scare birds away to trapping and killing or harrassing them to make them leave the area. Other methods involve destroying their nesting sites or firing canon as planes come in to land. Apparently a radar system that can pick up birds is being developed. In some cases, animals such as birds of prey or dogs are used to scare the birds. Some airports use repellents such as pyrotechnics, cannons or chemical repellents to deter birds. The birds can be trapped, harassed, deprived of food and shelter or, in the most extreme cases, killed. If birds are detected or expected in an area, the flight schedule can be altered or the aircraft can land on a different available runway. Radar systems that can detect birds are being developed but are not yet operational. Resources relating to this subject include an FAA FAQ and an article on about.com.
Resources relating to this subject include an FAA FAQ and an article on about.com. In some cases, animals such as birds of prey or dogs are used to scare the birds. Some airports use repellents such as pyrotechnics, cannons or chemical repellents to deter birds. If birds are detected or expected in an area, the flight schedule can be altered or the aircraft can land on a different available runway. The birds can be trapped, harassed, deprived of food and shelter or, in the most extreme cases, killed. Radar systems that can detect birds are being developed but are not yet operational.