You already know there are frogs surrounding your home, this is not because you see them but more likely because you can hear them. Their croaks echoing around your yard on a warm, summer night do not go unheard. You might be curious why frogs do this. It is one of the most unique sounds of all animals. So, why do frogs croak?
Much of the reason behind a frog’s croak involves a mating call, though this is not always the case. While male frogs do croak to attract a female mate, there are a few other reasons why they might croak. Whether it be at night or during the day, the reasons for frog croaks can vary.
Continue reading to learn why frogs croak. Depending on different species and purposes, not all croaks sound the same. It is interesting to learn why frogs croak in certain situations. Below is an explanation of why frogs croak, as well as different reasons for doing so.
Why Frogs Croak
For the most part, frogs croak to attract a mate. It is a natural instinct that frogs look to procreate, and the best way to do this is by utilizing their vocal cords to show off their croaks. With unique croaks for every species of frog, females know what to listen for when they are ready to reproduce. However, reproduction is not the only reason a frog may croak.
Frogs croak for various reasons. Different frog species have unique croaks, but an individual frog’s croak typically remains the same. A croak can be useful for:
- Mating
- Marking territory
- Protection
- Communication
- And more
The main reason frogs croak is in an attempt to find a mate. Males croak to find female frogs of the same species within the range of the sound of their call.
These calls can reach up to a mile, ensuring that female counterparts can hear. When a male frog calls, it is in hopes of attracting a female frog for successful reproduction. As you will see later in this article, croaking for mating generally happens at night.
Frogs also croak to mark their territory. Especially after moving to a new place, a frog needs to establish its presence. While this can be a dangerous task against surrounding predators, it acts as a way to communicate to other frogs that the frog croaking is in the area. This can provide a safer environment for frogs. If one frog is croaking in an attempt to mark its territory, another one will know not to invade the area.
With marking its territory being a form of communication for a frog, there are a few other reasons a frog may croak to communicate with its surroundings.
- In some cases, frogs may croak to alert signs of danger to surrounding frogs.
- Other times, there is a chance a frog might be croaking to find other frogs – not just for mating.
- Of course, a mating croak is a form of communication itself.
Sometimes, male frogs croak amongst each other as a sign of aggression. If one male frog has already marked his territory and another frog refuses to accept the fact, they may begin croaking at each other in an attempt to scare the other off. It is not unusual for male frogs to actually fight with each other over breeding territory.
Keep in mind that frogs are not inherently violent animals, so you may not ever run across two frogs fighting. Most of the time, when a male frog marks its territory, other frogs will stay away, even if the second party happens to be bigger or stronger.
Why Do Frogs Croak After It Rains?
Perhaps you have heard frogs croaking right after a rain shower. As you know, frogs are amphibians, meaning that most frog species can live half of their lives in water and half of their lives on land. With that said, the ideal environment for a female frog to lay eggs is in freshwater. In fact, you might even hear a frog croaking during a rainstorm. However, whether it be out of convenience or instinct, it typically happens after the rain has fallen.
So, if you hear a frog croaking after it rains, the chances are that it is a male frog searching for a female frog. Tadpole eggs thrive in freshwater, so finding a clean source right after a rain shower is one of the best ways to accomplish this.
Croaking to mate right after it rains is also advantageous for the likelihood of a male finding a female to reproduce with. With dense, low clouds in the sky, the echo of a frog’s croak can span even farther than a mile, allowing a wider range of females to hear the call.
In addition, the humidity in the air after it rains is also good for reproduction. Along with the freshwater in a pool that a female lays her eggs in, humidity adds to the effect of a beneficial environment.
Depending on what body of water a frog croaks from, they might be in different places. If it is shallow enough, they could actually be standing in the water awaiting the female. In other circumstances, they might be on the bank, a lilypad, or a nearby rock. Regardless, the male frog will be close enough to the water that the female will have no trouble finding him.
Why Do Some Frogs Croak At Night?
As you might have guessed, one of the main reasons frogs croak at night also deals with finding a mate. This, however, is purely for strategy. If a frog were to croak endlessly during the day, it would just be asking for an encounter with a predator. If a larger animal hears that croak, all it has to do is find the source of the croak to score an afternoon snack.
Frogs croak at night to avoid coming in contact with danger. Under the dark of night, most predators have less of a chance of finding them, even if they do hear the croaking. Even if it has not rained, it is common to hear an abundance of croaking while a male tries finding his female counterpart.
In rare cases, a frog might croak at night to communicate to other frogs around it that there is danger. As mentioned, frogs are usually able to stay hidden from predators when it is dark out, and they are fairly quick when they need to be. But with the chance that there is a threat, you may hear them croaking every now and then.
Again, a body of water is the main motivation for mating. It does not have to be dark out for a frog to croak in search of a mate. As long as they are in a wet enough area that supports tadpole eggs, you may hear a male croaking to a female at any time of day.
Frog croaks are so impressive because, when used for mating, they act as a male’s serenade to a female frog. It can be quite beautiful to recognize that frogs do not just croak for no reason. Whether or not a male frog can successfully attract a female is an art form. If its croak is good enough, it can successfully procreate and continue its own lineage.
Do Only Male Frogs Croak?
Since most frog croaks have to do with mating, croaks predominately come from male frogs. This does not mean that female frogs do not croak, but it is not common. When female frogs do croak, it can also be for reproduction.
Certain species of frogs use back-and-forth communication while croaking to mate. When a male croaks to find females to mate with within a certain radius, some female frogs will respond. This makes it easier for the frogs to find each other, and sometimes, it can help “excite” the male frog in preparation for mating.
Other times, female frogs may croak for other reasons mentioned: general communication, alerting danger, etc. Since croaks are usually a result of an attempt at mating, however, male frogs are usually the source of the noise.
If you are a lover of frogs, the chances are that you have gone searching for some before. The best way to track a frog to find it is by listening to its croak. Even if the frog is croaking for mating, you will not have to worry about any aggression. Of course, frogs are not large enough to pose any real threat unless they are poisonous.
Nonetheless, approaching a croaking frog may spook it away and ruin its chance to mate that day, but it is not typically a dangerous venture.
How Do Frogs Croak?
Learning about why frogs croak begs another question: how do frogs croak? It can be equally interesting to learn how frogs’ bodies allow them to croak. Read below to learn what happens in a frog’s body when it croaks.
Frogs are a part of a group of animals known as circular breathers. When executed correctly, they let out a croak. You are probably familiar with the bubble that fills up underneath a frog’s mouth when it croaks. Well, the process of croaking is quite interesting.
A frog uses air from its lungs to fill the bubble, or air sacs, under its head. As it breathes in, these air sacs move from under the frog’s head into its lungs. As the air sacs circulate through the frog’s body, the compression makes the croaking sound that you know all too well.
Frogs can do this as often as they like. This is why you may hear some species of frogs croaking through the night. It is a natural part of their body, so they can croak on and on while awaiting a mate, alerting for danger, or communicating anything else.
The species of frog determines what its croak will sound like. While croaks of the same species may sound the same to us, they are not perfectly equal. This is how the female frog’s choice comes into play. If she hears a call enticing enough to follow, that means the male frog has done a sufficient job of executing his croaks. So, while his call may sound similar to another male of the same species, it all depends on who does it best.
Can Frogs Hear Other Croaks?
Frogs have no problem hearing other frogs croak. Although they do not have outer ears, they have eardrums on the surface of their heads and inner ears within. So, when frogs listen for other frogs croaking, they are able to pick up the noises from the sides of their heads, just like humans.
What makes frog ears so unique is that their eardrums and inner ears are able to tell specifically if the croaks they hear are coming from a frog of the same species. This is especially advantageous in an area heavily populated by frogs. Female frogs are able to single out the croak from a male frog of the same species to reproduce successfully.
This can also be useful for male frogs marking their territory. If a male frog hears another male’s croak and recognizes it as a more powerful frog, the chances are that he is not going to try getting in the former frog’s way. On the other hand, larger, stronger frogs may try to take advantage of a smaller frog’s call to mark territory.
Different Frog Croaks
As mentioned, all frog species have different croaks. Some you have probably heard before, but others, perhaps not. Each frog call, even within one species, can be slightly different. Learning how to recognize different croaks will certainly boost your interest in frogs. Below are descriptions of some of the most noticeable and/or unique frog croaks you can hear.
Wood Frog Croak
The Wood Frog is an extremely common frog in the United States. Its croak is also very recognizable. Some people relate the sound of a wood frog’s croak to several ducks quacking together. It is quick, sharp, and repetitive. The relatively high pitch is all too common in and around ponds that may be by your house.
You can find wood frogs in:
- Shallow rivers
- Swamps
- And more
When croaking in an attempt at attracting a female wood frog, a male wood frog will spend a lot of its time actually in the water.
Northern Leopard Frog Croak
The Northern Leopard Frog is another of the most common frogs you will hear in the United States. In fact, if you have ever dissected a frog in your high school history class, it was probably a Leopard Frog.
A Northern Leopard Frog’s croak sounds like a mix of wood staggering against itself, and light purrs. It is quick and repetitive, just like a Wood Frog’s call, but the Leopard Frog’s croak is a bit deeper. This makes sense because Northern Leopard Frogs are quite large as a species.
Pacific Treefrog Croak
The Pacific Treefrog’s croak is similar to the two listed above, with a few tweaks. If you rub two smooth pieces of wood together, you will get that similar, repetitive call, but for the Pacific Treefrog, the croak is much more sporadic.
Honestly, sometimes it can sound like the tree frog is scared of its own croak. It is rarely a rhythmic call, with both long or short and low or high pitches. Depending on the Pacific Treefrog you find, you might hear something different. Do not be fooled: the species can still differentiate from other frogs.
Motorbike Frog Croak
You might be able to tell by its name, but the motorbike frog has one of the most unique croaks of all frogs. If you hear a car changing gears and speeding up, it may not actually be a vehicle. The Motorbike Frog’s croak very closely resembles a small engine revving up, changing gears, and gradually growing louder again.
You would be lucky to hear the croak of the Motorbike Frog, as most of them are found in Australia. Still, their call is quite an experience.
Bullfrog Croak
If you know anything about frogs, you have probably heard of the big, bad Bullfrog. Its croak is unique compared to any other frog croak. Bullfrogs are large, and even if you cannot see one, its call is evidence of that.
Quite literally, a Bullfrog sounds like a bull. It makes a long, strung-out “rum” noise. If other frog species were not already aware of a Bullfrog’s presence, they would surely know to keep away when they hear the bellow of the beast.
Gray Treefrog Croak
The Gray Treefrog also has a very noticeable croak. It is one of many frog species that have different croaks for different purposes. For example, when a male Gray Treefrog is looking for a female, its croak sounds like a quick, low trill. However, aggressive croaks between males sound like a sort of weeping.
They also have “release” calls that sound similar to their aggressive croaks. Both male and female Gray Treefrogs use the release call. It is quite impressive that they can differentiate between such slight changes in pitch, melody, length, and more.
Takeaway
In most cases, frogs croak in an attempt to find a mate. As a result, most frogs that croak are male. That does not mean, however, that female frogs never croak. Similarly, reproduction is not the only reason for croaking. Frogs croak for several communicable reasons that involve marking territory, being aggressive, and surviving.