When you first set out to get a new pet, you should always do research. This research should include basic care, appearance, illnesses, food, etc., as well as the basic anatomy of that animal. By understanding the care, needs, and makeup of that specific animal, you will be able to provide the best possible quality of care. Eyesight is incredibly important to betta, but how does this affect their overall care and wellbeing?
Bettas are sight-based predators, meaning that they rely more on their sense of sight than any other sense in order to survive. Without a honed sense of sight, they would starve in the wild. As such, they have evolved a rather advanced set of eyes, capable of seeing much as we see. But do their eyes surpass ours in any way, for example, can bettas see in the dark?
In this article, we will discuss what colors bettas can see, how their eyes work, sight when it is light vs night, and aquarium night lights and how they affect bettas.
What Colors Can Bettas See?
Although many people group all fish together, they are not created equal. For example, some fish see only in black and white, while others only lack a few color receptors, and still,others are capable of seeing more colors than we can. So, where do bettas fall on this scale?
Surprisingly, bettas can see nearly the exact same colors we can. They can see most of the colors that we can on the visible spectrum, though they are a tad bit different. The exact cones they have is unknown, though some speculate that they have an orange, green, and blue cone, while humans have a red, green, and blue cone. This may cause them to see the colors we see with just a slightly different hue.
In addition, eyesight can vary from betta to betta. While this may be comparable to colorblindness in humans, some bettas are unable to see red light. For the vast majority of fish species, if they are unable to see a light, it is likely red.
Water absorbs different colors at different rates, as each color has a different wavelength. Red is always absorbed by water first, meaning deep sea and river fish will never see the color red, so there is no need for their eyes to adapt to seeing it.
While betta fish are not deep-sea fish, it is possible for them to be unable to see red light. However, this is a relatively rare occurrence and does not reflect their genus as a whole. If you find that your betta can see red, your betta is capable of seeing all the colors we can, and possibly, some of the ones we can’t see.
How do Their Eyes Work?
While a betta’s color perception is incredibly similar to our own, their eyes possess other major differences and similarities. Like us, bettas are able to focus on a singular object with precision, something many fish can not do. However, unlike our eyes, they will see a more contrasted and blurrier image than us; essentially, while the image will be blurry, their eyes differentiate it from other objects very effectively through high contrast.
They are also unable to contract and dilate their iris quickly, unlike us. While our irises dilate closed quickly when a bright light is present, or open in dim lighting, it takes 30-60 minutes for a betta to fully dilate their iris one way or another.
This means that you should never suddenly turn on the aquarium light if no other lights in the room are on. They are unable to protect their pupils from the sudden light, and this can damage their eyes. Always turn on another light in the room for at least half an hour before turning on your betta’s aquarium light.
Bettas have monocular vision, meaning each eye sees a different image, while we have binocular vision, meaning both our eyes are used to focus on a single image. Animals with binocular vision have both of their eyes facing forwards and are more likely to be predators, while those with monocular vision have eyes on either side of their heads and are more likely to be prey.
While bettas are predators, they are also prey. Their monocular vision allows them to stay alert for any potential predators, while their unusual ability to focus on a single object allows them to also be a predator.
Light vs Night
Although it takes bettas a long period of time to adjust their eyes to the darkness, normally the amount of time it takes for the sun to set, can they see once their eyes adjusted to the darker environment? As cool as it would be for bettas to have night vision, Unfortunately, they cannot see superbly well in the dark.
However, most fish, including many sharks living in murky water, have a “sixth sense” in which they can sense vibrations and any pressure changes in the water. Essentially, they can “see” the volume of any object in the water around them, especially if that object is moving.
While this is not as effective as normal sight, it prevents a predator from sneaking upon them, and can even allow bettas to hunt at night, though this is rarer. In the light, they are capable of effectively using their vision to locate any predators or prey and taking the proper measures.
Aquarium night lights are commonly sold in a deep blue or red color, as most claim that fish cannot see those hues. However, as previously covered, betta fish can see both of these hues as clearly as any other light. By shining this light down on your fish all night, they will not have restful sleep.
Fish do not need any light on at night, especially betta fish. Their lateral line and sixth sense will prevent them from swimming into any objects or endangering themselves with the light out. They will be able to maneuver around just fine, and no special night lighting is needed.
Do Bettas Like Being in the Dark?
Even though bettas can essentially “see” in the dark with their sixth sense, is that something they like to do? There is no evidence one way or another as to whether or not bettas prefer the light or the dark. It is most likely that they have a preference somewhere in between, similar to humans.
For example, if you’re tired, you’d probably prefer it if the room was dark. If you were eating, you would probably prefer to have a light on so that you could prepare your food and see what you are eating.
Bettas need the light to effectively catch prey, eat, and reproduce. At night, they prefer the darkness because a predator will not necessarily be able to see them while they are sleeping, and if they do, they will still be able to tell that a predator is coming.
It is best to keep your betta’s light on for 12 hours each day, and off for just as long. However, this is not always possible with aquariums, as algae overgrowth may occur, so your betta may have to settle for 6 or 8 hours of light instead.
They need a structured day and night cycle in order to regulate their bodies properly, and without this cycle, they will fall ill. It is more important that the light comes on and goes off at, or around, the same time every day, than it is to give them a 12-hour day and night cycle.
In conclusion, betta fish have very powerful eyesight. They are capable of seeing every color we can, and possibly even more. In addition to this, they are able to “see” at night with a sixth sense, one which senses very small vibrations and pressure movements in the water, giving them an idea of where everything is located. Even though they can “see” in both the light and the dark, they cannot hunt in the dark, nor can they fully sleep when it’s light, so they need each period of lighting in moderation.