Visible Light
Visible light refers to the light that humans can see. Visible light plays an important role in the health and well-being of reptiles in a few different ways. As discussed in the UVA section, reptiles have excellent color vision. Full spectrum visible light is an essential component of a reptile habitat to ensure that these animals are seeing their environment in a natural way. In addition to the visual aspect, many reptiles have other ways of sensing light. Some have a parietal eye, also known as the third eye, that is able to take in light and send it to the brain helping to set daily and yearly rhythms. The visible light that reptiles are exposed to helps them determine the length of the day, time of the day, season, as well as other information that is used to adjust many of their daily and seasonal behaviors.
There are several different ways of providing visible light. The ambient lighting from the room will influence terrarium lighting, but ideally, lighting specifically for the terrarium will provide the visible light for pet reptiles.
Many daytime heating lamps and UVB lamps will provide visible light, but there are some options to increase the available visible light and allow you, as a keeper, to manipulate Photoperiods.
What is a Photoperiod?
A Photoperiod is the amount of time each day that a plant or animal is exposed to light. In nature, the sun provides a natural photoperiod each day. This time is different in different parts of the world and different times of the year.
Why is it Important?
There is a lot of information that reptiles can get from the light around them, such as the time of day (morning, afternoon, dusk…) and time of year (season). With this information, animals can decide when it is time to hunt, eat, bask, breed, nest, hibernate (brumate) and more. These daily and yearly rhythms are an essential part of a reptile’s life. Even nocturnal species are able to monitor these lighting cycles and adjust their activities accordingly. Adjusting the daytime period can help bring about behavioral changes and may be necessary to induce breeding and other behaviors. In nature, animals are subject to varying daytime periods throughout the year. To best simulate natural conditions, create a shorter daytime period in the winter and a longer daytime period in the summer.
How to provide a Photoperiod
Providing a Photoperiod or Daylight cycle is a very important component of reptile keeping, and can easily be done by turning daylight terrarium lamps on and off. Many different timers are available to help automate terrarium lights and provide a regular photoperiod for your pets.
LED lighting is very energy efficient and is able to add a lot of visible light to a reptile terrarium without significantly increasing the temperature or using much electricity. This can be especially helpful for animals that appreciate lower temperatures, such as New Caledonian and Mountain species.
These two tanks both have the same heat and UVB lights, but the tank on the right has supplemental LED visible light.
Many live terrarium plants have a high requirement for visible light in order to thrive. Live plants can be beneficial as well as beautiful in many different habitats. LEDs are a great solution for providing the light required to keep many of these tropical and desert plants alive indoors.