Yes, dolphins can see.
In fact some species of dolphin have excellent vision and are able to see objects at very far distances.
The quality of eyesight a dolphin has often depends on its species.
While many species of dolphin are known for their excellent eyesight there are some species that have poor or limited eyesight where they can only see short distances or objects that are very close in proximity.
A few species such as the amazon river dolphin can only make out certain distinctions of light variations and shapes that are within a few feet in front of them making these marine mammals essentially blind.
Although dolphins are able to see it is unclear whether or not dolphins are able to see in color.
Receptor cells, cones and rods are all responsible for providing animals with the tools they need to see and detect color.
It is believed that a lower number of cones correlates to either having limited color perception or near complete color blindness and dolphins posses fewer cones than land mammals such as humans.
Whether or not a dolphin has excellent eyesight becomes much less important in dark areas or at great depths where both light and shapes begin to dim and appear the same.
To assist dolphins regardless of their ability to see objects, shapes and light these marine mammals are also equipped with echolocation.
Echolocation allows dolphins to see their environment in the darkest of areas and provides them with the ability to detect the direction, location, size, speed, density and location of various objects in their area, which makes it easier for them to find food and maintain awareness of nearby threats.
Dolphins use echolocation by sending out a series of clicks which emits sound waves that come into contact with various objects in the surrounding.
As the sound waves bounce off of the objects in the area it returns to the dolphin at a certain speed, angle, frequency and vibration that it gives them specific information to allow them to detect exactly what objects are inhibiting their surrounding environment.
Whether its fish or squid that the dolphin is hunting or a shark that the dolphin is avoiding echolocation plays a significant role in their survival.
And as stated earlier echolocation becomes extremely important to dolphins (such as the amazon river dolphin) that have limited eyesight or in areas where light is extremely limited or nonexistent and the ability to bump into objects or predators becomes much more likely.
Third, to assist dolphins even further in their oceanic environment these marine mammals have a really acute and strong of hearing.
In fact sound travels four times faster in water than it does on land and acts as an advanced warning system for dolphins allowing them to keep track of what’s in their environment.
By combining good eyesight and hearing with echolocation dolphins are at a great advantage in the ocean compared to other sea creatures and animals that rely primarily on sight alone.