- The African clawed frogs that I breed in my aquarium reproduced. Can I release the juveniles in a pond close to my house?
No. This release would constitute a serious threat to the environment, this species is invasive and has an unfavourable impact on local wildlife. According to the decree of 30th July 2010, it is forbidden to introduce living specimens (eggs or live animals) of African clawed frog into the natural environment and throughout the French territory, intentionally or not.
For further information : Decree of 14 february 2018
- Can I hold a Bullfrog in an aquarium? If so, what regulation applies?
No. Since the 1st January 2015 and the entry into force of the European Regulation on the prevention and management of Invasive Alien Species, the detention of bullfrogs in captivity is prohibited.
- Can I hold an African clawed frog in an aquarium? If so, what regulation applies?
The detention of individuals of African clawed frog is possible provided that you have the necessary administrative authorizations, according to the articles L413-1 to 4 of the Code of the Environment and the decree of 10 August 2004: the holder must have a certificate of capacity and a prefectural authorization of opening.
- Can I breed African clawed frog in my garden pond?
No. It would be an introduction in natural environment. According to the decree of 30th July 2010, it is forbidden to introduce living specimens (eggs or live animals) of African clawed frog into the natural environment and throughout the French territory, intentionally or not.
- Are subspecies or breeding varieties of African clawed frog also regulated?
Yes, subspecies or varieties (albino forms …) remain are African clawed frogs and therefore the regulation also applies. Some regulations concern the Pipidae, which is even larger and may include Hymenochirus, Pipa, Pseudhymenochirus and all Xenopus (eg Xenopus tropicalis = Silurana tropicalis). The decree of the 10th August 2004 sets the conditions for authorization of holding animals of non-domestic species in breeding, selling, renting, transit or public presentation (excluding Pipa ssp, however) establishments.
- Can individuals of African clawed frog and Bullfrog be sold in pet shop?
Since the 1st January 2015 and the entry into force of the European Regulation on the prevention and management of Invasive Alien Species, the sale or the cession of African clawed frogindividuals in captivity is prohibited.
Nevertheless, African clawed frog individuals can be sold in a pet shop, provided that the selling establishment and the purchaser have individually the necessary authorizations: certificate of capacity and prefectural authorization of opening.
- African clawed frog individuals have invaded my pond. What should I do?
You have observed African clawed frog individuals? Tell us, it is important! For this, several possibilities:
Depending on the location of the observation, we will transmit the information to our local partners who will contact you.
- Bullfrog individuals have invaded my pond. What should I do?
You have observed Bullfrog individuals? Tell us, it is important! For this, several possibilities:
Depending on the location of the observation, we will transmit the information to our local partners who will contact you.
- What are the impacts caused by the populations of Bullfrog and African clawed frog introduced in France on local fauna?
Both species have a generalist diet such as native amphibians. However, due to their large size, particularly the Bullfrog, adults are important competitors and predators for the majority of the faunal populations in these environments.
The Bullfrog adult consumes especially many amphibians and strongly impacts local populations. It can also consume reptiles or small mammals.
The diet of African clawed frog extends from copepods to amphibians and fishes. Preferred prey varies according to local availability but selective sampling on different groups has been observed: molluscs, dipterans, dragonflies and amphibians. Its introduction in Sicily has led to the drastic reduction of some indigenous amphibian populations. In addition to its size, its impact is probably related to its presence all the year in the aquatic environment and its high resistance to adverse conditions such as the draining of a river or a pond.
Finally, both species represent a high health risk for indigenous amphibian populations. They are healthy carriers of the fungus Batrachochytrium dendrobatidis, present in France. This pathogen is responsible for massive mortalities on several continents and is considered as global threat to these vertebrates. The African clawed frog and the Bullfrog are also carriers of Ranavirus which are also the cause of epizootics (diseases affecting, in a more or less extensive region, an animal species or a group of species as a whole). The two species therefore contain major pathogens whose risk of transmission to local populations of amphibians increases with the expansion of colonized areas.
- How to recognize an African clawed frog?
The female measures up to 13 cm compared to 5 to 10 cm for the male. The African clawed frog has an overall morphology very different from European species: its body is rather flat, its head small without eardrums, its eyes arranged on the top of the head, its skin smooth and rather slippery when grasped. Its front legs are very short while its hind legs are very developed and have large palm. The first three toes have black claws. Its colouring varies from one individual to another, from yellowish to dark brown with spots. Individuals sold in pet shop are often albinos. Finally, one of the most characteristic criteria for identifying an African clawed frog is the presence of “seams” on its flanks, giving it a Frankenstein look!
The tadpoles are also easily recognizable: they have two remarkable barbells next to the mouth.
- How to recognize a Bullfrog?
The Bullfrog is an Anura which can reach an imposing size: the largest individuals can measure up to 25 cm and weigh nearly a kilogram. With typical frog-like appearance without dorso-lateral folds and has a very large eardrum: its diameter is equal to the female’s eye and twice to males’s eye.
Its dorsal face colour varies from olive green to dark brown and is dotted with darker spots. Its ventral face is cream coloured. Males have a yellowish throat.
His song, a kind of cow moo, earned him its name.
Tadpoles are large at the end of development: they can exceed 15 cm in length and have small typical blackheads in pinhead’s form.
Caution: Juveniles and adults can be confused with Marsh Frogs. Be sure to check the identification criteria of the Bullfrog: no dorso-lateral folds, diameter of the eardrum greater or equal to the eye, yellow ventral face for the males … If possible, take a photograph to verify serenely!
Tadpoles can be confused with those of green frogs, Alytes or Pelobates, which may also have large sizes.
- Why are the Bullfrog and the African clawed frog considered as Invasive Alien Species?
To be considered as an Invasive Alien Species, an introduced species must fulfil various criteria:
- Have been introduced by human, intentionally or accidentally, out of their natural range of distribution;
- Be naturalized, have the capacity to establish and reproduce in the environment of introduction without human intervention;
- Be able to proliferate and spread geographically;
- Causes negative ecological, economic or health impacts.
The populations of Bullfrog and African clawed frog present in France have been introduced by humans, reproduce, spread and have impacts on local populations, in particular on amphibians and aquatic invertebrates.
- Where do the African clawed frog and the Bullfrog come from?
The African clawed frog is native of southern Africa (from the Cape in South Africa to Nigeria and Cameroon).
The Bullfrog is native to the United States East coast.
- How and why were the Bullfrog and the African clawed frog introduced in France?
Since a long time, African clawed frog is used in laboratory, by the past for pregnancy test, and currently especially for biological research. For this purpose, it is still today used in breeding centres. In the 80’s, the closure of one of them located in Bouillé-Saint-Paul, in the Deux-Sèvres, is at the origin of its involuntary introduction into the natural environment.
The Bullfrog was first introduced in Gironde in 1968, after about ten individuals were brought back from the United States for their ornamental character. The population grew and some individuals were displaced on the Bassin d’Arcachon and in Dordogne, thus creating two new foci of introduction in Aquitaine.
A second population was also introduced in Sologne, in the department of Loir-et-Cher.
- I found an African clawed frog individual or a Bullfrog individual. Can I bring it at home and release it in an aquarium or a pond?
The current French regulations prohibit the introduction into the natural environment of individuals of African clawed frog. Nevertheless, transport and detention are not prohibited. However, pay attention, the fulthe detention is subject to authorization (obligation to hold a certificate of capacity).
The Bullfrog is cited on the list of invasive alien species of Union concern. It is therefore prohibited to introduce them into the European Union, keep them, breed them, transport them, sell them, to use them or exchange them.
Tell us the observation! For this, several possibilities:
Depending on the location of the observation, we will transmit the information to our local partners who will contact you.
- The Bullfrog is present in France. Where was it introduced?
In France, there are four nuclei of Bullfrog population. Three are located in the Aquitaine region and one in the Centre-Val de Loire region.
In Aquitaine, the three populations are divided into three sectors:
- From its point of introduction in Gironde, in the town of Arveyres, the Bullfrog has mainly colonized an area from Libourne to Saint-André-de-Cubzac. It also colonized the Dordogne valley and is now present in the Gironde estuary.
- It is also present on the Bassin d’Arcachon, mainly on the towns of Biganos and Teich.
- Finally, it was introduced in the Dordogne where it is present in three sectors, two are located in the territory of the Parc Naturel Régional Périgord-Limousin.
In the Centre-Val de Loire region, the known population is present in Sologne, in the department of Loir-et-Cher. Its current distribution is limited to three towns.
- The African clawed frog is present in France. Where was it introduced?
African clawed frog individuals were introduced in the north of Deux-Sèvres in the 80’s. The population thus formed dispersed and now covers the northern of Deux-Sèvres and southern of Maine-et-Loire.
In 2015, a new population was discovered in Gironde, in the town of Ambarès-et-Lagrave. The pond where the discovery was made is also already colonized by the Bullfrog.
- What are the techniques used to fight against the African clawed frog?
Currently, the fight against the African clawed frog is based on a single technique targeting adult individuals. Baited traps with dog food are placed in the colonized ponds and recuperated the following morning. Then, a sort of captured individuals occurs, individuals other than African clawed frog are released.
LIFE CROAA aims to develop new techniques targeting other stages of development.
- What are the techniques used to fight against the Bullfrog?
Several studies have been conducted to identify the most effective techniques. The current techniques target all stages of development:
- Research and destruction of eggs. Clutches are sought from mid-May to mid-August. The clutches found are removed and deposited on the ground in order to destroy them by desiccation (method of removing water from a body).
- Fishing of ponds with or without the installation of dispersal barriers. Pond fishing with net is effective to eliminate tadpoles. The installation of dispersal barriers around the pond prevents the escape of juveniles. Sometimes pond fishing can only be carried out if the pond has been drained in order to lower water levels. Tadpoles captured are sorted, tadpoles of indigenous species or other aquatic individuals are released.
- Night shots. This operation mainly targets adults, but also juveniles (caution, the risk of confusion with the green frogs are very important). It requires the intervention of two persons, one equipped with a lighthouse and the other with a rifle. This technique is the most effective way to get rid of adult individuals.
- What is the status of the Bullfrog and the African clawed frog at European level?
The Bullfrog is cited on the list of invasive alien species of Union concern. This status implies that it is forbidden to introduce it into the natural environment, transport it, hold it, sell it, exchange it.
Although present in other European countries and causing damage to local aquatic populations, the African clawed frog is not currently listed, but an evaluation work is in progress.
- Have the Bullfrog and the African clawed frog been introduced to other European countries?
Yes. In Europe, the Bullfrog is present in Belgium, France, Germany, Greece, Netherlands, Spain and United Kingdom.
The African clawed frog is present in Portugal, Italy, France, United Kingdom and Germany.
