Can Lobsters Swim? (Explained)

When we think about how lobsters move, we often imagine them walking using their legs. But can lobsters swim if they don’t even have any obvious body parts to do it? If you ever wondered about that, we’ll talk about that in this blog post. However, let’s begin with a quick answer:

Lobsters can swim either forward by using their walking legs (also called swimmerets), or they swim backward by rapidly flexing their tail. Swimming backward is a more common way of swimming as lobsters swim away much faster and effectively run away from their predators.

However, this certainly doesn’t tell the whole story. Below, I’ll explain more about how lobsters swim, how fast, and how far they can swim. Furthermore, I’ll explain why they swim, if they swim in their larval stage, and if you can encounter them swimming up to the surface. Next, I’ll explain how lobsters move in general. Read on!

How do lobsters swim?

Lobsters, depending on the purpose and species, can swim either forward or backward. They either use the movements of their four pairs of walking legs, also called swimmerets or pleopods, or their tail, depending on the “swimming style”.

Lobsters swim backward by producing a series of rapid swimming movements, often called tail-flip. These movements are created by rapidly flexing and extending their abdomen, which is the lower part of their bodies, commonly called the tail.

The primary function of their swimming movements is the escape from predators. When the animal wants to escape quickly, it flexes and extends the tails, which immediately takes the lobster upward and backward. Then, it continues swimming backward to the point when it’s safe again.

Interestingly, while speed is most important during the escape swim, lobsters can also steer their body by rotating their tail. Thanks to this, lobsters have availability to change swimming directions.

Forward swimming is a less common way of swimming as it’s less effective. It’s powered by the beating abdominal pleopods, which are located behind the claws. During the swimming movement, they outstretch four pairs of swimmerets below their body and use them to beat in synchronous waves to swim forward.

While swimming forward, lobsters can’t effectively navigate and change directions like backward swimming.

How fast and how far do lobsters swim?

Lobsters usually don’t swim for too long. As soon as they locate a safe shelter, they’ll hide under rocks again. Regarding their speed, scientists recorded it from 13 to 30.7 cm (5 to 12 in) per second during swimming forward. During backward swimming, lobsters usually travel at 36 cm (14 in) per second, but their first movements are much more rapid.

The distance, speed, and duration of swimming vary depending on lobster species, sexes, size of the animal, and how quickly it flexes its tail. For instance, larger and stronger animals often prefer to scare the predator with a defensive posture instead of escaping.

When the animal size increases, the tail is less effective in lifting the animal off the bottom due to its mass. However, females have no size-dependent change in escape behavior, as they’ll most likely escape rather than scare predators away.

Why do lobsters swim?

Most of the time, lobsters walk on the bottom of the ocean and stay in their shelters. Therefore, they usually swim in response to predators. They’re especially quick during their backward swimming, allowing them to escape rapidly. Sometimes when you scare the lobster and blink an eye, you might not even notice where he swam away.

In the video below, you can notice how quickly the lobster runs away from the person holding it:

Another reason lobsters swim is to travel longer distances in order to find new shelter or food. They can’t travel fast when they walk, so finding a new home would take them a long time.

Why do they swim backward?

Usually, when lobsters swim backward, they’re being attacked. So, when they swim backward, they face the predator attacking. Therefore, by keeping their claws out, they can defend themselves while escaping. If the lobster swam forward, it would be more vulnerable to its predator.

Do lobsters swim in their larval stage?

Adult female lobsters carry their eggs under their tail. After they hatch, larvae are released, and they become free-swimming larvae. This means that technically lobsters swim in their larval stage; however, they can’t control where they’re going.

Lobster larvae swim into the water column and swim together with the current. After a few weeks, they develop part of their bodies and settle on the ocean floor. In the postlarval stage, they become capable swimmers when they develop their tails.

Do lobsters swim up to the surface?

Lobsters don’t swim up to the surface. They also usually don’t come up to the shore as crabs do. The reason is simple – they just don’t have any reasons to do it. The trip to the coast could be even risky as lobsters can’t breathe air. They have gills, and they can’t survive a long time out of water.

Lobsters also eat other animals that live on the bottom of the ocean, such as crabs, mussels, clams, sea urchins, fish, and sometimes even other lobsters. They simply wouldn’t find any food on the surface, or at least it would be difficult for them to catch it.

Interestingly, when lobsters find themselves on the surface for some reason, they can’t swim back down because they don’t swim vertically but horizontally. In order to do that, they just stay still and wait until they sink to the bottom. When they swim, their average swimming height usually ranges between 0.5 and 0.9 m (20 and 35 in).

Can all species of lobsters swim?

They are about 75 species of lobsters divided into four major families: clawed lobster, which includes Europen lobster, and well-known American and Norway lobster. The other three families that don’t carry claws are spiny lobsters (very common in the Caribbean), slipper lobsters, and coral lobsters.

Each of these lobster families and species differs in many aspects. For instance, some do, and others don’t have claws. There are also differences in their carapace, antennae, or life cycle, especially during the larvae stage.

However, all these species have a tail and swimmerets that they use for swimming. Therefore, yes, all lobster species can swim.

How do lobsters move?

We know how lobsters swim, but how do their normally move around the seafloor? Adult lobsters don’t use swimming as their primary way of locomotion. They walk using their walking legs and by contracting and retracting their tail.

Unlike crabs, lobsters move forward or backward but can also move sideways. Lobsters move to find food, females to reproduce or to migrate. Interestingly, many lobsters migrate seasonally to find cooler waters.

Sources

• Newland, Philip L., et al. “Escape Swimming in the Norway Lobster.” Journal of Crustacean Biology, vol. 12, no. 3, 1992, pp. 342–53. JSTOR, https://doi.org/10.2307/1549027. Accessed 20 Aug. 2022.
• Jeffs, Andrew G., and Rebecca C. Holland. “Swimming Behaviour of the Puerulus of the Spiny Lobster, Jasus Edwardsii (Hutton, 1875) (Decapoda, Palinuridae).” Crustaceana, vol. 73, no. 7, 2000, pp. 847–56. JSTOR, http://www.jstor.org/stable/20106348. Accessed 21 Aug. 2022.