The Loa Water Frog (Telmatobius dankoi) is a critically endangered frog from Chile. They are found only in 1 location, Las Cascadas along the Loa River. Sadly, the river has become inhabitable for the frogs. The river had dried up to illegal extraction of water for mining, agriculture, and urban development.
Last year in 2010, the last known Loa Water Frogs were taken from the wild to be kept safe in captivity. Unfortunately, there was only 14 frogs left. The frogs were flown to the National Zoo of Chile. The frogs arrived malnourished and unfortunately, 2 of them died. The other 12 are in great shape.
Lately, the researchers started to notice the female frogs gain weight and the male’s skins changing. Then, the female frogs laid eggs, a first for the species in captivity! The eggs then hatched into tadpoles! A total of 200 tadpoles of the Loa Water Frog hatched. Now, the zoo has the challenge of raising these tadpoles in hopes of saving the species.
It is a doggy dog world out there and salamanders and newts need ways to protect themselves from doggy dogs. They face threats of being eaten by a variety of different animals from birds, fish, snakes, frogs, raccoons, and even other salamanders. This doesn’t scare salamanders and newts because they have a variety of ways to avoid being eaten.
Poisons and toxins are great way for salamanders and newts to defend themselves against predators. No one wants to eat a salamander or newt if it could make them sick or kill them. Some salamanders try to warn predators that they are poisonous with their bright colors. This is called aposematism.
Eastern Newt Eft photo by Jason Quinn
Red Salamander photo by by Leif Van Laar
Other salamanders mimic the colors of poisonous salamanders to trick predators. The Red Salamander (Pseudotriton ruber) resembles the Eastern Newt eft (Notophthalmus viridescens) and it is thought that this keeps predators from eating the Red Salamander.
Other salamanders and newts arches their back to show off their stomach, which can be brightly colored, when they are threatened. This is called the Unkenreflex.
The Fire Salamander (Salamandra salamandra) can squirt its toxins at any enemies that come near. The Iberian Ribbed Newt (Pleurodeles waltl) is able to puncture their ribs through their skin to warn off predators.
Besides trying to poison a predator, some salamanders try to camouflage into their habitat to hide from the predators. These salamanders and newts tend to be cryptic colors such as green, brown, black, or brown, making it easy to blend in.
Another amazing way that salamanders can protect themselves is actually dropping their tail. This is called caudal autotomy. They drop their tail and hope that the predator tries to eat it instead of them. Then the salamander regrows their tail but at a cost. The tail stores fats and has a role in locomotion. Also dropping the tail can compromise their immune system. Tail dropping is used as a last resort.
Today, we have a guest post from my friend – Chris. He wrote this for an assignment at school and thought my readers would like to read it.
When male green tree frogs are looking for mates, they call with advertisement calls, telling the world “I’m here, this is my territory, come get me.” These advertisement calls are mostly the types of calls that you hear whenever you go out in the woods, especially in the spring. They’re the calls most frequently used by frogs, and the ones that are the most predictable, allowing us to use them to recognize frog species the same way we do with bird calls. However, these calls have a side effect; They don’t just attract female frogs, they also bring in other males that want the females and territory that the calling frog might have.
Bringing other male frogs leads to aggressive interactions between male frogs frequently. These don’t look quite like the types of fights that we may be used to though, as they tend to result in the frogs showing off with aggressive calls to each other until one backs down. These calls do a good job acting as a proxy for a fight without the risk of injury and other costs of actually fighting, as the larger, more fit frog usually wins.
A study from Christopher J. Leary from the University of Mississippi looked at how both these aggressive calls and advertisement calls affected both frogs emitting them and frogs hearing them. It had previously been established that advertisement calls from males generated more sex hormone production in females around, as well as in the calling male, but this study addressed also how it affected listening males, and how the aggressive calls impacted both males involved. He found that winners of these fights between male frogs showed slightly higher levels of corticosterone, a stress hormone, immediately after the fight, but the losing male showed much higher levels of the corticosterone. This may change these losing frogs strategies to reproduction in the future. Changes to the frog’s body chemistry begins to explain a phenomenon called satellite males, where some frogs stop trying to compete for mates and territory, and instead try to be sneakier and intercept females for quick mating opportunities. This change was hard to understand in the context of evolution, as giving up mating opportunities or competing for mating opportunities seemed like it would never be beneficial from an evolutionary perspective, but if it is caused by lost conflicts, this may help us understand why frogs would make this change of strategy.
His results on the impacts of advertisement calls on listening males were less clear though. He found slight drops in androgen, the main sex hormone, levels among males listening to other male’s advertisement calls, which was backwards of the expected result. Previous research had suggested that frogs would produce more sex hormones when hearing other males advertising, which makes logical sense, as this would lead to them seeking out conflict with the other males looking to steal their mates and territory. Leary’s result is suggested as an adaptation by these frogs to try to prevent rival males from hearing their song and attempting to come fight for their territory and mate, but this result seems unclear, given its disagreement with some previous research.
Other studies will surely be done in the future to try to verify this surprising result, and to investigate the complicated dynamics of frog interactions when looking for mates. But the major result of the impact of the aggressive calls on other frogs helps us better understand how frogs find and compete for their mates, and may help explain satellite males.
Reference: C.J. Leary. 2014. Close-range vocal signals elicit a stress response in male green treefrogs: resolution of an androgen-based conflict. Animal Behavior, 96 (2014), pp. 39-48
Today, March 20th, is World Frog Day! If its not obvious, I really like frogs and so do you if you are reading my blog! Frogs are currently facing serious threats to their survival currently. From information from the IUCN Red List site, I have made a graph of the conservation status of all the frogs. This graph excludes the categories extinct in the wild and data deficient.
Over a quarter of these frog species are listed as Endangered or Critically Endangered. This is not good and we need to stop these trends. Now let’s see what happens to the graph when we add in species that are listed as data deficient (ones that the IUCN doesn’t have enough info to categorize them).
Around a quarter of frog species we don’t even know their conservation status. We don’t know if we need to help protect them. We need to find out these answers.
We all have heard of poisonous frogs such as the Golden Poison Frog or the Cane Toad but do you know that there are venomous frogs?
What is the difference between poisonous and venomous? To be venomous, the animal needs to inject the toxin into the blood stream of it’s victim. Snakes inject their toxins with their fangs, scorpions with their tails, and stingrays on their barbs. A poisonous animal doesn’t inject any toxins, they just produce them. Lazy poisonous animals.
There are only two known venomous frogs in the world and both happen to come from Brazil. These species are the Bruno’s Casque-Headed Frog (Aparasphenodon brunoi) and the Greening’s Frog (Corythomantis greeningi).
You are probably wondering, how do these frogs inject their prey? Fangs? Super cool claws? Well sorry to disappoint but they literally use headbutts to inject their venom. They have spines on their head that connect to a gland that produces the venom. How weird.
How deadly is the venom of these frogs? It was calculated that a single gram of the toxic secretion from a Bruno’s Casque-headed Frog can kill around 80 people. It’s venom is 25 times more toxic than pit vipers from the genus Bothrops. The Greenig’s Frog is not as toxic but still like twice as toxic as the pit vipers.
It’s almost Valentine’s Day and I know all of you are wondering, how do frogs have sex? Today is your lucky day because I’ll be explaining it. There are many different ways that frogs and toads reproduce and if I try to cover them all, this post might become its own book.
Frogs and toads generally start breeding in early spring or late winter if the weather is nice. They also start breeding at the change from dry season to wet season. The breeding season ends in summer, giving the offspring the longest time to develop before winter or dry season comes.
The most well known way that frogs reproduce is in the water through external fertilization. Male frogs can be found in bodies of water calling for female mates during the night. Some frogs breed in vernal ponds / ephemeral pools (temporary ponds created by melting of snow and spring rain) because these ponds lack fish that can prey on their offspring. Other frogs look for more permanent bodies of water because their tadpoles don’t undergo metamorphosis until after the next winter. For this sort of reproduction, females come into the territory of a male and the male jumps on her back. This mating position is called amplexus.
Males will often try to mate with anything, including different species of frogs, toads, and fish. Male frogs don’t have penises, they have an opening called the cloaca where the sperm is released. Females have this opening too, where the eggs come out. The male grips the female from behind so that when he releases his sperm, there’s a better chance at fertilizing the eggs. Other males sometimes will come into the frog’s territory and also jump on the female while the other male is holding her. They sometimes even form giant piles of frogs or toads. Occasionally, it gets so rough, the female is killed. Usually though, the female releases her eggs and the male fertilizes them and she goes on her merry way.
While some frogs mate in the water like that, many others mate on the ground, and some even mate in the trees. During reproduction in the trees, the couple makes a foam nest out of the eggs and other secretions to keep the eggs dry. For the species that reproduce on land, the eggs might never need water because when they hatch, the offspring is immediately a froglet and not a tadpole.
Not all frogs use external fertilization, some use internal fertilization. There are different ways that frogs and toads use internal fertilization. Some frogs such as the Tailed Frogs from Ascaphidae, perform internal fertilization then lay fertilized eggs later. The Tailed Frog’s tail is used in fertilization.
The Nimba Toad (Nimbaphrynoides occidentalis) is the only known viviparous frog / toad. The frog is pregnant for 9 months and the babies feed off the mom’s secretion.
The genus Nectophrynoides and theGolden Coquí (Eleutherodactylus jasperi)are the only known ovoviviparous frogs and toads, where they have eggs inside them that hatch and then they give birth to little froglets.
Ok just kidding about them being the only ovoviviparous frogs because there is another one but it’s kind of different. The Fanged Frog (Limnonectes larvaepartus) is also ovoviviparous but instead of giving birth to froglets, it gives birth to tadpoles.
From there, we learn that frogs have weak sphincters so that if they fart, we probably can’t hear it. It also goes on to say that African Bullfrogs and Horned Frogs do fart and it smells bad. Maybe I need to set up a recorder to see if Rayna farts.
If you want to learn more about animal farts, you can pre-order a book that Nick Caruso co-authored called Does It Fart?: The Definitive Field Guide to Animal Flatulence on Amazon today! It will be released on April 3rd this year. You can also get a copy for me because I’m poor.
Have you ever wondered what the difference between a salamander and a newt is? Well wonder no more. If you don’t know, salamanders refer to any species in the order Caudata. The order contains over 700 different species in 10 different families. To explain what a newt is, we have to look at just one of those 10 families – Salamandridae. Don’t be afraid by the name, there are newts in there. The family is split into three different subfamilies or groups. They are Pleurodelinae, Salamandrinae, and Salamandrininae. The subfamily Pleurodelinae contains all the newts! There are 16 different genera in the subfamily and includes the majority of the species in the family. Why isn’t it named Newtidae instead of Salamandridae?
So now you know the taxonomic differences between newts and salamanders but what are the observable differences? Adult newts live more of an aquatic or semi aquatic life style while salamanders generally live more of a terrestrial life style. There are some salamanders that live aquatic life styles such as the Axolotl but the majority of adult salamanders are terrestrial (land loving). Because of the fact that adult newts are more aquatic, newts have tails that are wider and more paddle like and they have more webbing on their feet. Not all newts have these tails and some do live more of a terrestrial lifestyle.
The One Toed Amphiuma (Amphiuma pholeter) can grow up to 13 inches. They are the smallest of the three different kinds of Amphiuma. They are found in Southeastern United States.
The Eastern Tiger (Ambystoma tigrinum) can grow up to 13 inches but usually between only 6 to 8.25 inches long. It is found in the eastern United States, southeastern Canada, and Mexico.
The record largest Western Tiger Salamander or Barred Salamander (Ambystoma mavortium) measured in at 13 inches but it was also a neotenic salamander. They usually are 6 to 8.5 inches long. They are found in the western United States.
Coastal Giant Salamander (Dicamptodon tenebrosus) can grow up to 13 inches long but usually only up to 6 inches longs. They are found in the western part of the United States and Canada.
The Common Mudpuppy (Necturus maculosus) is the largest mudpuppy species. The longest one recorded was 19 inches long. They are usually between 8 to 13 inches long. It is found in the Eastern United States and Southeastern Canada.
The Hellbender or Snot Otter (Cryptobranchus alleganiensis) often grows between 11 and 22 inches long but the record length recorded is 29 inches (2.4 feet) long. It is found in the Southeastern United States.
The Greater Siren (Siren lacertina) can grow up to 3.2 feet long but are usually recorded at lengths between 20 to 30 inches long. It is found in the Southeastern United States.
Three Toed Amphiuma (Amphiuma tridactylum) can grow up to 3.4 feet long but usually only between 1.5 feet to 2.5 feet long. It is found in Southeastern United States.
Two Toed Amphiuma (Amphiuma means) can grow up to 3.8 feet long but are usually around 14.5 to 30 inches long. It is the largest of the Amphiumas. It is found in the Southeastern United States.
Japanese Giant Salamander (Andrias japonicus) measures in at 4.9 feet long, making in the second largest salamander in the world.
Chinese Giant Salamander (Andrias davidianus) is the largest salamander in the world. It has been observed to grow to 5.9 feet but lately most of the salamanders found are smaller than that. The average length is usually around 3.9 feet long.
Hello reader! You may have stumbled upon this site somehow and you might be wondering, what is froggin? Froggin or Frogging is the act of catching frogs just like fishing is catching fish. Gone Froggin is about non-lethal, safe frog catching. We don’t want any frogs to die because keeping a healthy populations of frogs allows everyone to enjoy froggin for many years.