Are Shrimp Nocturnal? This Study Has Some Surprising Results

Some shrimp species are nocturnal and spend their daylight hours in hiding. Nocturnal shrimp use their impressive eyesight to locate food and avoid predators. Some shrimp species stay hidden during the day by hiding in caves or under rocks.

Many shrimp species are nocturnal. According to PetMD, you are unlikely to see this nocturnal crustacean during the day. These shrimp prefer nighttime because the darkness protects them from large fish. Although many people do not try, shrimp species can be active during the day under certain circumstances.

This article will discuss the details about nocturnal shrimp, including why shrimp only come out at night and why shrimp hide. 

Are Shrimp Nocturnal? 

Shrimp are nocturnal since they are most active at night. According to PetMD, many fish owners never see shrimp in their tanks because they are inactive during the daytime. Fear and vulnerability keep the shrimp sleeping through the day until the intelligent crustacean is confident that it can hunt at ease. 

However, a shrimp with the right tank conditions can adjust to a diurnal nature. The more comfortable they become in their environment, the more likely they will come out during the day. Wild shrimp and store-bought shrimp are considered nocturnal, and however, it is entirely possible to make them enjoy the daytime.

What Shrimp Species Are Nocturnal?

Most shrimp species are either nocturnal or diurnal, and many people already have one of the most common nocturnal shrimp species in their aquariums, the Peppermint Shrimp. Also known as the Candy Cane Shrimp or the Pep, this is a nocturnal crustacean that you will only see at night.

However, like many other nocturnal species, the Peppermint Shrimp will become active during the day if you set the right conditions. Its adaptability has caused this shrimp to understand its environment. 

Species of shrimp that are nocturnal include: 

  • Freshwater shrimp 
  • Peppermint shrimp
  • Amano shrimp
  • Ghost shrimp
  • Cherry shrimp

Almost every shrimp species is nocturnal. 

Why Are Shrimp More Active at Night?

Shrimp are more active at night because they feel safer. Since shrimp are small fish, they must be cautious while foraging for their food. A need for safety is why they prefer darkness, and most species are nocturnal unless they learn otherwise. The aquatic crustacean was initially a daytime crustacean that was forced to evolve.

Shrimp Prefer Darkness

According to Aqua Life Hub, freshwater shrimp are the most active at night because the darkness protects the shrimp from large fish. This nocturnal shrimp refuses to leave their hiding places during the day, even if they have a tank to themselves. Fear of predators is a recurring pattern for many nocturnal and non-nocturnal shrimp.

Other Fish Are Inactive During Nighttime

During the nighttime, most other fish are inactive. The inactivity of other fish allows shrimps to sneak out of their hideaways. During the day, the areas these shrimps explore are crowded with large fish and lethal predators. At nighttime, there are inactive, and the shrimp can safely use them to travel where they need to go. 

Shrimp Evolved Into Nocturnal Crustaceans

Shrimp evolved into nocturnal crustaceans because it was challenging to scavenge during the daytime, and large predators would eat the small crustaceans who had no way to defend themselves. Eventually, shrimps realized they had to evade predators and evolved into nocturnal animals. 

Small crustaceans like shrimp are incredibly vulnerable when scavenging for food during the day. These crustaceans feel less vulnerable as they scavenge for food at night. Shrimps come from their hiding places after fish have gone to sleep so they can scavenge as much food as possible under darkness. At night, shrimp can gather as much food as they want.

Why Is My Shrimp Hiding?

Your shrimp may hide for several seasons, like incompatibility with other fish or being nocturnal. These shrimp are small fish at the bottom of the food chain. If there are other fish in your tank, the first things you should observe are other fish and available space.

Shrimp Hide from Incompatible Fish

Shrimp are often forced to hide from incompatible fish who view shrimp as food. Even if the shrimp want to leave their hiding place, the fear from this predator prevents your shrimp from going. It is best to remove incompatible fish from your tank or invest in a larger tank.

Shrimp Hide when Stressed

If your shrimp are hiding but are not a nocturnal species, they might be experiencing a stressor. 

Stressors include: 

  • Incompatible fish
  • Nowhere to hide
  • Underfed or overfed
  • Overcrowding
  • New environment (tank, decorations, fish, etc.)

When shrimp become stressed, they may hide and refuse to come out, even during the nighttime. 

Does Lighting Affect Shrimp Activity?

Lighting can impact shrimp activity because shrimp prefer darkness, making shrimp feel more comfortable and safe from larger predators. So, if you have other fish in your tank, your shrimp might wait to come out until your tank is dark.

How Can I Make My Shrimp Active During the Day? 

Making your shrimp active during the daytime is possible if you create the ideal environment for your shrimp. They are nocturnal by nature, and however, you can alter this by encouraging your shrimp to become more active during the day. 

Reduce Your Fish Population

The easiest way to reverse your shrimp’s nocturnal nature is to reduce the fish population to only shrimp. Or to very few compatible fish. Creating a dedicated shrimp tank is ideal for your shrimp because it gives them the safest environment possible. They will appreciate the safety and comfort of being the only fish in the tank.

In contrast, you may also add only compatible fish. Once they realize the fish around them are entirely consistent, you will notice a personality change from your shrimps. They will feel more comfortable and may start to come out during the day. Give it time, and eventually, they may become diurnal. 

Upgrade Your Fish Tank

Consider upgrading to a larger aquarium if your tank is too small. A population cluster may cause your shrimp to feel stressed, which will make your small shrimp even more fearful of the daytime. After upgrading the size of your tank, upgrade the hiding places in your tank. Add plenty of places for your shrimps to sleep on, including logs, plants, etc.

Do Shrimp Sleep?

There is still much unknown about sleep in shrimp. However, there is some evidence to suggest that they do, in fact, sleep. One study found that when juvenile shrimp were placed in a dark environment, they became less active, and their heartbeat slowed. This suggests that they may be engaging in some form of sleep. Additionally, when shrimp are deprived of sleep, they become more sluggish and have impaired memory.

This suggests that shrimp do indeed need some time to rest and rejuvenate.


My name is Jaap, and I am a passionate shrimp and fish enthusiast. I rediscovered my love for this hobby with my son and want to share our knowledge and tips with you on this aquarium blog. We cover topics such as setting up and maintaining an aquarium, feeding and breeding your shrimp and fish, and creating the perfect environment for them to thrive.

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