Can Great White Sharks See? Unlocking Their Visual Mysteries

Great white sharks (Carcharodon carcharias) rely heavily on their sense of smell and ability to detect electromagnetic fields to find prey. However, their sense of sight also plays an important role in their hunting strategies and interaction with their environment.

In this article, we’ll take an in-depth look at what science has revealed about great white shark vision and visual capabilities.

Do Great Whites Have Good Eyesight?

Great white sharks do have fairly good eyesight, especially considering their evolutionary background as predators that rely more on smell and electroreception to find prey. However, their visual acuity is thought to be much less sharp than many other shark species that rely more on eyesight when hunting.

Some key things to understand about great white shark vision:

• High rod density – Their retinas contain a very high density of rod cells, which function better in low-light conditions. They are thought to have decent night vision as a result.
• Low cone density – They have very few cone cells, which detect color and fine detail. As a result, their daytime vision is not as sharp, and they likely see in black and white or grayscale rather than color.
• Decent sensitivity – Despite the low cone density, some estimates put great white visual acuity in daylight conditions at around 20/40 in human terms. So reasonably sharp, but not with very fine detail or color perception.
• Wide fields of view – Their eyes are positioned to allow for a wide binocular field of view of around 35 degrees vertically, helping them fix targets or detect fast-moving objects in different directions.

A recent 2021 study in the Journal of the Royal Society Interface specifically examined video footage edited to match a great white shark’s visual capabilities and compared human swimmers and surfers to typical seal prey shapes and movements. The researchers concluded very little visual distinction would be possible for a juvenile white shark viewing targets from below in murky conditions.

So, in summary – moderately good eyesight in terms of light sensitivity and motion detection, but not with ultra-fine detail or color vision. Their eyes play a supporting role to their other highly adapted hunting senses.

What Do Great White Sharks See?

Based on the structure and capabilities of their eyes, what great white sharks actually see likely looks quite different to human vision.

Again, the high rod density and low cones mean they would see mostly greyscale in daylight conditions, rather than color vision. Their vision is also thought to be more optimized for detecting contrast and movement rather than seeing highly defined shapes or objects. Underwater visibility conditions also limit how far and how sharply they can see depending on water clarity.

Typical seals range from 5-6 feet in length as adults, quite similar to the size of many human swimmers and boards. So the combination of poor visual acuity, lack of color detection, and similarity in size of humans and prey likely causes juvenile white sharks to mistake humans for seals in murky nearshore waters while hunting.

Some researchers believe great whites may also be able to perceive some degree of polarized light, which could enhance their ability to detect contrast between prey items and the background waters. This may help reveal more defined shapes of nearby prey.

It’s also possible great whites could possess some basic color vision thanks to a secondary retinal pigment that may allow them to detect some hues, especially at close distances. However, this capability likely pales in comparison to many other shark species.

In summary, what great whites actually see probably looks more like a grainy, black-and-white silent film with decent contrast and motion detection rather than a highly colorful and defined world. Their other senses fill in the blanks that vision cannot provide.

How Does Sight Help Great Whites Hunt and Navigate?

Despite visual limits compared to many shark species, great white sharks rely significantly on vision to successfully go about their hunting behaviors and navigate through their environment.

Some of the key ways great whites use vision include:

• Target movement detection – Their excellent motion-detecting capabilities allow great whites to rapidly spot potential prey items, even at long distances in some cases. Vision alerts them to interesting targets worth investigating.
• Assessing threats – Great whites can visually inspect unfamiliar objects, potential threats like sharks from other species, or unnatural debris and determine if they are non-threatening or worth avoiding.
• Identification – At closer ranges, great whites rely on vision to identify familiar prey species, investigate irregularities, or determine if hidden prey may be present based on associated cues.
• Final attack positioning – Vision provides the accuracy needed for precise body positioning and distance judgment during the final moments of an attack on prey.
• Navigation – By recognizing underwater landmarks, light conditions, and other visual cues, great white sharks can navigate familiar and unfamiliar areas more effectively.

In essence, vision connects the early detection capabilities of other senses with the precision and identification needed for their specialized hunting strategy closer in. It likely also reduces energy expenditure by not needing to fully investigate threats or prey that can be dismissed visually from a safer distance.

However, juvenile sharks with less hunting experience may suffer more cases of mistaken identity between humans and seals in murky conditions based on limited visual capabilities to clearly differentiate prey shapes and movements.

How Does Vision Vary Between Individuals and Underwater Conditions?

There are likely some variations in visual capabilities between individual great white sharks based on age, condition, genetics, injuries, and environmental factors that can impact vision over a lifetime. However, all great whites likely experience significant vision changes depending on water conditions.

Turbidity caused by sediment, pollution, phytoplankton, wave action, and other factors can significantly reduce underwater visibility and visual range. Even water temperature, lighting conditions, and time of day can impact what they are capable of seeing at any given moment.

Some evidence suggests great white sharks may be able to visually detect prey items up to distances of over 25 meters in very clear ocean water with calm conditions. But in murky coastal water or areas with heavy sediment, their visual range could be reduced to just a few meters – forcing them to rely much more extensively on smell and electroreception instead.

These changing visibility conditions could help explain why great white sharks have evolved such exceptional non-visual hunting senses as their primary tools. Vision likely plays a supporting role when available light and water clarity is high, but cannot be relied upon exclusively as their hunting conditions are too widely variable.

Conservation efforts are complicated by limited understanding of shark vision and reasons for bite incidents with humans. Better grasping their actual visual capabilities can help inform smarter protection policies that keep ecosystems and marine life safe, including humans.

How Does Shark Vision Compare to Other Shark Species?

Among over 500 shark species, visual capabilities run the gamut from sharks with excellent vision to those that are likely nearly blind. Great whites have better vision than some species, but fall short compared to various sharks considered to have exemplary eyesight.

Some sharks with superior vision include:

• Tiger sharks – Possess color vision and higher acuity thought to be on par with some birds of prey thanks to higher cone density.
• Mako sharks – Have exceptionally large eyes and pupils with a higher proportion of cones, allowing color vision and extremely sharp eyesight critical for hunting fast prey.
• Hammerheads – With eyes mounted on the ends of their uniquely shaped heads, they benefit from 360-degree binocular vision for improved depth perception.

The difference in visual capabilities between species comes down to evolutionary adaptions to their particular habitats and hunting strategies. Coastal sharks like tigers, mako, and hammerheads that rely heavily on vision to target fast-moving prey evolved sharper capabilities. Open ocean sharks like great whites adapted other senses instead that are less impacted by murky waters and long distances.

So, while great whites benefit from decent vision, they are definitely not sharks with the best eyesight compared to species where vision plays a much more vital role. But their multi-sensory approach with exceptional smell and electroreception more than makes up for any visual limitations.

Key Questions About Great White Shark Vision:

Can great white sharks detect colors or see vibrant colors like red?

No, most evidence suggests great white sharks only have a grayscale vision based on their rod-dominated retina and very few cones for color detection. Some limited color differentiation may be possible due to a secondary pigment, but great whites are unlikely to see most colors like red and instead rely more on contrast.

How do great white shark eyes compare in structure and function to human eyes?

Human eyes have over 100 times higher density of cone cells than great whites, allowing for the detection of fine detail and a wide color spectrum. But great whites have a high density of rods for improved low-light capabilities. The sharks also have a reflective layer behind the retina to enhance available light, and their eyes are spherical, unlike the elongated human shape.

Can great whites close or blink their eyes?

Great white sharks do not have eyelids, so they are incapable of blinking or fully closing their eyes. Instead, a protective third eyelid called a nictitating membrane can extend up for basic eye coverage while attacking prey. This helps protect the eye during these aggressive moments but does limit vision.

Is there evidence of great whites using eye contact or gazing behavior with humans?

Some human encounters with great whites have reported seemingly sustained eye contact or “looking back” behavior from these sharks as they swim by closely. However, researchers debate this, as it is unclear if great whites fully understand or care about eye gaze behavior sometimes expected by humans during encounters.

Are there any recorded incidents of a great white shark losing vision from injuries or illness?

There are a few confirmed cases of injured great white sharks losing vision or having serious visual impairments. One well-known great white nicknamed “Homer” is totally blind, apparently from either debris or seal bites damaging his eyes. Despite no vision, this shark has managed to survive and even mate – a testament to their outstanding non-visual hunting capabilities.

Conclusion

While great white sharks may lack the dazzling color vision and visual acuity of some shark species, their unique eyes are well adapted to serve their specialized predatory role as powerful hunters.

With excellent capability to detect contrast and movement from a distance and finely assess prey at closer ranges – vision works in concert with smell and electromagnetic detection to make the great white shark one of the ocean’s most formidable marine predators. Sight plays a supporting but important role, giving these sharks yet another sensory tool to utilize where ideal conditions allow.

There is still more to learn about exactly what great whites are capable of seeing, how vision aids their navigation and social behaviors, and how much variation exists between different individuals. But current science gives us a strong basic understanding of how vital vision remains in the lives of these incredible sharks, even as other senses take the main stage.