Why do birds make a 90 degree dive when hunting for fish?

to minimize the affect of refraction





thus their aim point when at 90 degrees is exactly at the fish not at a ';bent'; view of the fish. - depending on the depth, the amount of refraction could result in a poor hit or even a miss.





it's all about ';what's for lunch'; -- so the fish that are marginally more successful are the ones who dive straight into the water. I've watched them do it it is pretty cool.Why do birds make a 90 degree dive when hunting for fish?
I imagine that there is some angle that carnivorous birds do swoop down, but I highly doubt it is 90 degrees. The birds would basically be falling at this angle, and would die on impact from the surface of the water.Why do birds make a 90 degree dive when hunting for fish?
It's the best shot that these birds can take mate the thrill of going thru a high speed is achieved only when u r focused in one straight direction try it for urself and u'll know how thrilling it feels :D zoooooooom
The angles at which plunge-diving birds strike the water vary, and depend on species, age of the bird, position of the sun, and other factors. As far as I know, the reasons are open to speculation, but some are fairly obvious. Those are that at vertical impact the penetration depth is greater, and the element of surprise greater. Glare from the surface is likely smaller, although that can be minimized by diving away from the sun. In addition, the odds of miscalculating the position of the fish due to refraction are less.
Its all about the refraction of the light in the water. THis means that the water 'bends' the light as it passess through, making it look light something is one place, when it is not actaully there.





In order to minimize thing, birds dive perpendicular (90 decrees) to the water so that the refraction is essentially neagated. This allows them to better know where the fish actually are.





It is of coure faster to dive in such a manner as well, but that it only a secondary component of the reason.





Hope that made sense.
Reduce shadows to keep from alerting the fish to their presence.
why ppl dive in to water vertical?
It's also faster.