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A great many birds including egrets and birds of prey hunt fish.
Some species wade through the shallows and pick at fish like the egret.
Others dive into the water to chase fish their prey like the great cormorant.
While several species of eagles and hawks also prey on fish, many limit their hunting to fish that have been washed up on the shoreline.
The black kite, for example, can often be seen flying over the seashore, but it fs actually crustaceans and small animals like rodents that they fre hunting, and not fish.
There is, however, a bird of prey closely related to eagles and hawks that feeds primarily on fish, dynamically swooping down to pluck them from the water below.
The osprey.
While the osprey is a migratory species by nature, recent years have seen an increase in birds staying in the same area throughout the year.
These ospreys mainly inhabit the mouths of large rivers and particularly favor man-made structures such as steel towers for their nest.
The osprey is often mistaken for the black kite due to similarities in their physique and habitat.
However, the two can be easily told apart by the way they fly.
Ospreys bend their neck to peer down at the shallows when flying over rivers and near the seashore, momentarily stopping in midair if they spot any fish.
This hovering action only lasts for a moment, with the osprey making a split-second decision to either glide or flap its their wings based on the fish fs movement and its chances of successfully catching it.
Once they have spotted their prey, ospreys will thrust both legs forward and align their talons with their line of sight.
Ospreys can even use their superb aerial agility to swiftly change direction at the last moment to line fish up.
The osprey catches fish by swooping down at high speed and sticking its legs into the water to grab its prey.
In addition to sharp talons, the osprey also has rough scaly skin ideally suited to catching fish.
Fish are held by the head with one foot and by the back with the other so they can ft slip away, with the head is orientated to the front and the tail to the rear on the long flight back to the nest.
The osprey has evolved specifically for hunting fish.
The most phenomenal aspect of their ecology, however, is the ability to spot fish from so high up.
Ospreys, eagles and hawks are known for their superb eyesight.
Some birds of prey even have special abilities, like the kestrel of the falcon family Falconidae and its ability to see near ultraviolet light.
It is speculated that ospreys use polarized light to detect fish in water, which has a different refractive index to air.
Another theory says their cognitive capabilities include a kind of zoom lens.
When ospreys thrust their legs forward in midair it appears as if they have already determined the size of their prey fs head and back, something only possible if they zoom in to measure the actual size of the fish being hunted.
This theory is yet to be empirically validated, and there is still much we don ft understand about their vision.
Supposing they do have such a mechanism, ospreys would be magnifying images up to 150 times.
Achieving the same kind of zoom with a lens the size of the osprey fs eye is impossible even with today fs most advanced technology.
While we may have developed a better understanding of sensors from an anatomical perspective, science is yet to shed light on how living creatures perceive this information and apply it to the unique behavior they display.
Humans do not have such refined sensors with which to measure the natural world.
However, humankind posses the power of analysis, one that goes beyond our natural limitations.
The protection of this diverse and beautiful earth through the analysis of nature is a mission that has been entrusted to humankind.