On warm rainy nights in the spring, it is common to see salamanders and other frogs migrating to breeding sites, or hunting for food. However, when the daytime comes, salamanders become harder to find.
Most salamander species are either nocturnal or crepuscular and are most active at night or in the low-light hours right before the sun rises and sets. However, a few salamander species are diurnal, meaning they’re most active in the daytime.
Many animals that prey on salamanders are less active at night, making a nocturnal lifestyle advantageous.
There’s also less competition for resources. Fewer creatures are looking for a drink of water or on the hunt for prey at night, which means salamanders have a better chance of success.
Most Salamander Species Are Either Nocturnal Or Crepuscular
All animals are either diurnal, nocturnal, or crepuscular. Humans are diurnal creatures, meaning we are primarily active in the daytime and sleep at night.
Most salamanders on the other hand are nocturnal or crepuscular. This means they are most active at when the sun is down, or in the low light hours right before the sun rises or sets.
Salamanders have several distinctive anatomical features suited for their nocturnal, or crepuscular lifestyle.
The eyes of most salamanders are highly adapted to see in low-light conditions, even when humans are not able to see anything.
Many salamander species are also biofluorescent, which means they can absorb visible and ultraviolet light and re-emit it at a lower energy level. In essence, they ‘glow in the dark.’
This may help salamanders perceive other individuals in low-light conditions.
7 Reasons Why Most Salamanders Are Nocturnal
As earlier mentioned, a nocturnal lifestyle is advantageous to salamanders, and many other animals. The conditions at night provide the perfect environment for frogs to come out of their daytime retreats.
1. There Are Fewer Predators at Night
Salamanders feel more comfortable at night because they’re not as easily visible to potential predators. Many of the animals that prey on salamanders are less active at night, making it safer for salamanders to come out.
For example, many predatory bird species such as hawks, and eagles are strictly diurnal, meaning they don’t hunt at night.
This allows salamanders to come out more into the open without the fear of being eaten by hawks, and many other predators.
While there are also predators at night, salamanders can blend into their environments more easily and have a better chance of going unnoticed in the cover that the darkness provides.
2. Salamanders Can Search For Food At Night
Many of the insects that salamander prey on, such as crickets, are usually active at night, remaining hidden during the day. This means nighttime is a good time for hunting.
In addition, salamanders hunt more easily in low-light conditions and avoid being seen by the prey.
3. There’s Less Competition For Resources At Night
Salamanders hunt the same prey as many other animals. They also use water sources that are used by other animals.
Being nocturnal helps salamanders avoid conflict with many animals. Fewer creatures are looking for a drink of water or on the hunt for prey at night, which means salamanders have a better chance at success.
4. Night Because The Temperatures Are Cooler
Salamanders are ectothermic (cold-blooded) animals, which means they cannot regulate their body temperature. Their body temperature changes with that of their surroundings.
When it’s warm, their bodies soak up the heat, and their body temperature rises. When it’s cooler, their body temperature falls.
In other words, they depend on their environment to keep them comfortably cool or warm.
As the temperature changes at different times of day, they move around in their environment to regulate their body temperature.
When their body temperature is low, they move into the sun to warm up, when it is high, they move to the shade or cool water to cool down.
Night temperatures are usually cooler because the sun is not out at night. The ground cools because it emits more radiation than it gains from the atmosphere.
This means salamanders can come out and be more active without the fear of overheating. The cool night weather is perfect for them to emerge from their daytime retreats.
5. Salamanders Can Conserve Water At Night
Salamanders are amphibians, and love cool, humid environments. They usually hang around shaded areas near ponds, swamps, streams, lakes, and other water bodies – where they can cool down and keep their skin moist.
Relative humidity increases at night due to the drop in temperature, so salamanders can come out without worrying about their skin drying out.
In simple terms, the air is like a sponge. When air temperature increases, the air capacity increases, so the air can hold more water vapor.
However, as the air temperature drops, the air capacity decreases, so the air can hold less vapor. This leads to an increase in relative humidity.
6. Salamanders Can Search For Mates At Night
The cooler nighttime temperatures, higher humidity, and fewer predators provide the perfect environment for salamanders to migrate to their breeding ponds.
This is especially true during the wet season when most salamanders and other amphibians reproduce.
7. Salamanders Can Avoid Encounters with Humans At Night
As earlier mentioned, humans are diurnal creatures, meaning we are primarily active in the daytime and sleep at night.
A nocturnal lifestyle allows salamanders to avoid many potentially dangerous encounters with humans.
Some Salamanders Are Diurnal
Although most salamander species are nocturnal, there are some exceptions. For example, California newts (Taricha torosa) are diurnal. This means they’re most active in the daytime – just like us humans.
These newts produce highly potent poisonous secretions that make them distasteful or lethal to most predators.
For this reason, they do not have many natural predators. They can be active during the day without worrying about being preyed on by other animals.
Conclusion
Most salamander species are primarily either nocturnal, or crepuscular meaning they are most active when the sun is down, or in the low light hours right before the sun rises or sets.
Frogs have several distinctive anatomical features suited for this lifestyle, one being an ability to see in low-light conditions.
Being nocturnal helps salamanders avoid the heat of the day, and also many predators such as hawks are active during the day.
A handful of salamander species are diurnal and are most active in the daytime.
That said, being diurnal is quite rare for amphibians, so you can be sure most of the salamanders you see in the wet season are nocturnal.
Sources:
Lamb JY, Davis MP. Salamanders and other amphibians are aglow with biofluorescence. Sci Rep. 2020 Feb 27;10(1):2821. doi: 10.1038/s41598-020-59528-9. PMID: 32108141; PMCID: PMC7046780.
Rozenblit F, Gollisch T. What the salamander eye has been telling the vision scientist’s brain. Semin Cell Dev Biol. 2020 Oct;106:61-71. doi: 10.1016/j.semcdb.2020.04.010. Epub 2020 Apr 29. PMID: 32359891; PMCID: PMC7493835.