Amphibians are skillful survivors, adapting physical and behavioral traits to ensure their continuation. One of their most classic traits is laying countless frog eggs during mating seasons, but not all frog species lay the same number of eggs each time.
Frogs generally lay between 2 and 30,000 eggs per clutch depending on the species and climate. Most aquatic frogs in North America lay between 1,000 and 6,000 eggs once per year, yet a handful of frog species in South America do not lay eggs at all, and give birth to live tadpoles or froglets.
Below is a list of common frog species and how many eggs they lay on average:
|Frog Species||Location||Number of Eggs|
|Poison Dart Frog||South America||2 – 12|
|Glass Frog||South America||14 – 30|
|Black Rain Frog||Africa||25 – 30|
|American Green Tree Frog||North America||200 – 400|
|African Clawed Frog||Africa||500 – 2,000|
|African Dwarf Frog||Africa||500 – 2,000|
|Spring Peeper||North America||900 – 1,000|
|Tomato Frog||Madagascar||1,000 – 1,500|
|Australian Green Tree Frog||Australia||1,000 – 2,000|
|Common Frog||Europe, Asia||1,000 – 2,000|
|Pacman Frog||South America||1,000 – 2,000|
|Gray Tree Frog||North America||1,000 – 2,000|
|Wood Frog||North America||1,000 – 3,000|
|Northern Leopard Frog||North America||1,000 – 6,000|
|Green Frog||North America||1,000 – 7,000|
|Leopard Frog||North America||2,000 – 6,000|
|African Bullfrog||Africa||3,000 – 4,000|
|American Bullfrog||North America||15,000 – 25,000|
|Cane Toad||Australia||25,000 – 30,000|
You may notice that many frogs in South America like Poison Dart Frogs and Glass frogs lay very few eggs. However, they can lay eggs 1 to 4 times per year because of the favourable climate they live in. Although such species may lay far fewer eggs than other frog species, they may still lay a reasonable number of eggs per year since they can reproduce more frequently.
Here is a table of how many clutches these frogs lay per year:
|Frog Species||Number of Clutches||Number of Eggs|
|Poison Dart Frog||1 – 4||2 – 12|
|Glass Frog||1 – 4||14 – 30|
|Black Rain Frog||1||25 – 30|
|American Green Tree Frog||1||200 – 400|
|African Clawed Frog||1 – 4||500 – 2,000|
|African Dwarf Frog||1 – 4||500 – 2,000|
|Spring Peeper||1||900 – 1,000|
|Australian Green Tree Frog||1 – 3||1,000 – 2,000|
|Common Frog||1||1,000 – 2,000|
|Pacman Frog||1||1,000 – 2,000|
|Gray Tree Frog||1||1,000 – 2,000|
|Wood Frog||1||1,000 – 3,000|
|Northern Leopard Frog||1||1,000 – 6,000|
|Green Frog||1||1,000 – 7,000|
|Leopard Frog||1||2,000 – 6,000|
|African Bullfrog||1 – 2||3,000 – 4,000|
|American Bullfrog||1||15,000 – 25,000|
|Cane Toad||1 – 2||25,000 – 30,000|
Poison Dart Frogs, Glass Frogs, African Clawed Frogs, African Dwarf Frogs, Australian Green Tree Frogs, African bullfrogs, and Cane Toads generally live in favourable environments for reproduction year-round and can lay eggs 1 to 4 times per year.
American Green Tree Frogs, Spring Peeper, Common Frogs, Gray Tree Frogs, Wood Frogs, Northern Leopard Frogs, American Bullfrogs, and Green Frogs typically live in climates where hibernation is necessary to survie winter and only lay eggs once per year.
The number of frog eggs laid per clutch generally depends on the frog species and surrounding environment. Frog species living in dry or high latitude, colder climates typically lay eggs once per year, while species living in tropical climates can reproduce multiple times throughout the year.
Frogs Lay Thousands of Eggs for Survival Reasons
Most frog species generally release hundreds to thousands of eggs, and up to 30,000 per clutch. Frogs lay large numbers of eggs to balance the high mortality rate frogs experience during their early life stages due to predators, environmental, and biological factors.
Laying large numbers of eggs is a classic survival technique, critical to frog survival. Large numbers of eggs generally help balance out the high mortality rate amongst frogs, as there are countless fatalities during their early life stages.
Frogs are threatened by many biological factors, environmental issues, and natural predators. Many frog eggs are eaten shortly after being laid. They are eaten by predators roaming waters, skies, and terrestrial spaces.
While frog species may lay hundreds or thousands of eggs per clutch, only a small fraction of the clutch will live long enough to mature and reproduce in the future.
Based on the observations made during a scientific study, it was found that there was only a 0.1% survival rate from the frog egg phase to maturity (Thurnheer et al. 2000). Scientists have studied frog egg survival rates numerous times, estimating that only around 1 in 50 frog eggs will survive to reach maturity (CTNF).
Most frogs leave their eggs after they are laid, meaning that they have no defense against hungry predators. As a result, the eggs laid by frog species that care for their young will generally have higher survival rates. Examples of frog species that care for their young include some Poison Dart Frogs and Glass Frogs, who often remain near their frog eggs until they develop into young froglets.
Not All Frogs Lay Eggs
While using external fertilization and laying eggs is most common across various frog species, a few species do not lay frog eggs at all. However, this does not mean these species do not reproduce, as they simply employ more creative methods for survival.
Such species include those that may house the eggs in the body, eventually giving birth to live tadpoles or live froglets. Although froglets and tadpoles will still face the dangers posed by the environment, they are more equipped to evade such threats compared to the previous capabilities during their helpless zygote state.
Around one dozen frog species use internal fertilization, although many of these frogs still lay eggs after reproduction.
Scientists are still conducting investigations into their evolutionary reproductive methods, but it is believed that frogs use different methods to increase their survival chances in the wild. The frog eggs are far less vulnerable to natural predators and threats, which are abundant in communal habitats worldwide.
More About Frog Eggs
Thousands of frog eggs may seem excessive at first glance. But, only a small fraction of these eggs will survive to see adulthood, which is further influenced by parental behaviors, existing dangers in the wild, and environmental conditions. Still, laying frog eggs in high quantities is a classic survival technique, as it has a drastic impact on the species’ overall population and continuation.
Learn more about frog eggs on our blog:
- Do Frogs Lay Eggs or Give Birth?
- When Do Frogs Lay Eggs?
- Where Do Frogs Lay Their Eggs?
- How To Get Rid Of Frog Eggs
- Frog Eggs: Everything There is to Know
- Toad Eggs: Everything There is to Know
Sylvie Thurnheer, Heinz-Ulrich Reyer, Spatial distribution and survival rate of waterfrog tadpoles in relation to biotic and abiotic factors: a field experiment Zoological Institute, University of Zurich, 8057 Zurich, Switzerland, Corresponding author: H.-U. Reyer.