Fabulous Frogs for World Frog Day

March 20^th was World Frog Day and it was created to raise awareness of frogs and the challenges they face.

What’s the big deal about frogs?

There are over 7500 species of frogs in the world. Out of the 7500+ species of frogs, almost 900 species are endangered and over 500 species are critically endangered, but 146 of these have been marked as possibly extinct.

Frogs, and other amphibians, are classed as an ‘indicator species’ (think of canaries in a coal mine) and are usually the first indicator of something being wrong in the environment. Due to their porous skin and inhabiting both water and land habitats, they are exceptionally vulnerable to environmental changes and toxins. The absorption of toxins like pesticides, pollutants and chemicals can cause deformities or death in frogs and other amphibians.

Native frogs

In the UK there are 2 native species of frogs: the common frog and the pool frog.

The common frog, as the name suggests, is widespread across the UK, and are often the ones you’ll find in your garden pond. The pool frog, however, was thought to be extinct in the wild in 1995. These have since been reintroduced at 2 sites in Norfolk but are considered critically endangered in England. They are protected by law making it an offense to kill, injure, capture, disturb and trade or sell them. It is also an offence to destroy their breeding or resting sites.

Native toads

There are 2 native species of toad in the UK: the common toad and the natterjack toad.

The common toad, like the common frog, is widespread across the UK, and if you see a toad, it will likely be this one. The natterjack toad is rare and hard to find as they are generally only found in coastal sand dune habitats.

These aren’t the only frogs and toads that you’ll find in the UK though as several species have been introduced in the past, including non-native pool frogs, edible frogs, marsh frogs, North American bullfrogs, and the midwife toad. The Amphibian and Reptile Conservation website has a handy downloadable pdf to help you identify the different amphibians you may find in the UK.

How you can help our native frogs and toads

• Avoiding using pesticides or other chemicals in your garden.
• Create an area in your garden for frogs – a pond, an overgrown area, or a log pile. If you don’t have the space for a pond, something like a washing up bowl dug into the ground can work if you provide the frogs with a safe way to climb out (e.g. a small log sat in the bowl that reaches the surrounding ground).
• Don’t put fish in your pond – these will eat frogspawn and tadpoles!

Amphibians at WWP

At Wingham Wildlife Park, we currently have 4 species of frogs and 1 species of toad. 

Lemur leaf frogs

When you visit the reptile house, you will find the ‘Frog Room’, this room houses our critically endangered lemur leaf frogs. This room has been set up to create the perfect temperature and humidity for the frogs and they have their very own rain system. Although you cannot enter the room itself, you are able to view our frogs from the large viewing window at the front. If you’re good at hide and seek you should be able to spot 1 or 2 of our frogs hanging out on the leaves, incredibly well camouflaged. Lemur leaf frogs come from Costa Rica, Panama and parts of Colombia. They struggle in the wild due to urbanization, agriculture, deforestation, invasive species, diseases, and collection from the wild.

White’s tree frogs

Our White’s tree frogs can be found in an enclosure in the reptile house and are well suited to the heat as these guys come from Australia. White’s tree frogs are currently listed as least concern on the IUCN Red List and can be found in large numbers in Australia. They are also popular frogs in the pet trade.

Argentine horned frog

Our Argentine horned frog is currently living off-show in the reptile house kitchen, but you may have been able to spot him if you have visited us previously. Affectionately named ‘Snoop Frog’, he spends most of his time buried in the dirt, waiting for an insect to pass by. Argentine horned frogs are listed as near threatened on the IUCN Red List with their numbers decreasing. The main threats for this species include urbanization, agriculture, pollution, invasive species, diseases, and collection from the wild for things like the pet trade.

Trinidad poison dart frogs

We also have a group of Trinidad poison dart frogs, which are also known as Yellow-throated frogs or the Trinidad stream frog. These frogs live on the land found in our alligator snapping turtle enclosure. They can be incredibly hard to spot as they are not only shy but also range from 2 – 2.8cm in length. Most of the time, team reptiles only see a handful of the frogs during their feeding time, where they hop out of their hiding spots for a second to catch their dinner and then dart back. This species is listed as least concern on the IUCN Red List, but like other frogs, is under threat from agriculture, logging, diseases, and invasive species.

Cane toads

We have a large group of cane toads here at Wingham. All of them can be shy during the busier times of the day. Cane toads are native to South and Central America but have been introduced into other areas of the world. Australia have had a huge problem with cane toads. They negatively affect the Australian ecosystems and the biodiversity of species since they were introduced back in 1935. Cane toads are tough toads and will eat almost anything so do well in the wild. As a result, they classed as least concern by the IUCN Red List.

Life cycle

Frog spawn

Most frog spawn can be found laid in large clumps in a body of water. This is what you will see from our native frogs here in the UK. But there are several ways in which frog species lay their spawn. Some frogs will deposit their eggs on a leaf, overhanging a body of water, protected by a jelly-like coating. Once the tadpoles are ready to hatch, they’ll fall off the leaf and into the water below. In addition to laying them on a leaf, some frogs will curl the leaf over their eggs. Others will lay the eggs in a small pool of water inside plants and flowers giving them a little extra protection. Some frogs will carry a single tadpole on their back until it turns into a froglet.

Toad spawn

Most toads, including UK toads will lay their spawn in long chains, rather than large clumps like frogs. Some toads (the midwife toad) will carry their fertilized eggs on their back until they hatch into a pool of water. Then in the odd case of the Suriname toad, they will hatch their toadlets from holes in their backs.

What’s the difference between frogs and toads?

All toads are frogs, but not all frogs are toads. This is because they all come under the same order: Anura – commonly called frogs. But within this order are the 2 families: ranidae (frogs) and bufonidae (toads).

Generally, frogs will have smooth skin that looks wet, while toads have bumpier skin which looks dry. Frogs have long, strong legs, with great jumping abilities. Toads on the other hand toads have shorter legs and although they can hop, they prefer to walk around.

Unique species

There are many cool and unique species of frog in the world, but here’s a handful of them…

Glass frogs

Their skin is see through! When you look at the underside of a glass frog, you can see their organs. They achieve this by draining their red blood cells into special crystal-lined sacs in their liver which they can then later re-disperse into their body. This translucent skin helps them camouflage and keeps them safe while they sleep.

Waxy monkey frogs

These guys produce a waxy substance which they then rub over their body to use like sun cream. This allows them to stay out in the sun for long periods of time without drying out. This substance also contains a natural opioid which is 40 times stronger than morphine.

Desert rain frogs

These frogs successfully live in hot environments and sand dunes. They bury themselves deep in the sand during the day and only come out at night, absorbing any moisture they need from the fog. Due to the lack of water available, they have adapted to skip the tadpole stage, and instead froglets will hatch straight from the eggs.

Golden poison frog

These carry 1900 micrograms of poison – enough poison to kill 10 adult humans! The were once used to taint Choco Indian hunting darts. The darts were rubbed on the backs of the frogs to cover them in poison; 1 frog could coat 2-3 darts. The frog would be unharmed, and the poison could stay on the dart for up to a year.

Greening’s frog & Bruno’s casque-headed frog

These are the first 2, and only (so far), venomous species of frog. These two species have been found to have small spines on their head which they used to inject the venom. The Greening’s Frog has venom more potent than a pit viper. The Bruno’s casque-headed frog has venom 25 times more potent than a Brazilian pit viper. They are able to kill 80 adult humans.

An easy way to remember the difference between poison and venom: if you bite it and you die, it’s poisonous, if it bites you and you die, it’s venomous.

African goliath frog

This is the largest frog species in the world, growing up to 32cm in length and weighing over 3kg. Additionally, they don’t possess vocal sacs and therefore cannot produce sound like other frog species. Instead, they open their mouths and make a whistling noise as their mating call.

Paedophryne amanuensis

This is not only the smallest species of frog in the world, but the smallest vertebrate in the world! They grow to a total length of 7.7mm – the size of a housefly. They live amongst the leaf litter in the forests of Eastern Papua New Guinea.