Phenomenal frogs of the Kogelberg: Our most threatened vertebrate

May 18, 2022 | Uncategorized

Frogs are quite simply phenomenal.

 

For example, did you know that some frogs can jump over 20 times their own body length? Or that many species of frogs are wonderful mothers – caring for their hungry tadpoles by depositing unfertilised eggs for their offspring to eat?

Left: Micro Frog, Microbatrachella capensis. Image: @alexanderr, iNaturalist. Right: River in Kleinmond. Image: LoveGreen Communications.

In the Kogelberg Biosphere Reserve, we really are fortunate.

We’re home to a number of frog species, including the Critically Endangered Micro Frog (Microbatrachella capensis).

This is one of South Africa’s smallest amphibians, growing to just 15mm in length. They occur in patches across a 10km square area in Betty’s Bay, surviving in acidic blackwater fynbos vleis. Incredibly, during the dry summer months, they bury themselves in the wetland soils and aestivate (essentially to hibernate in summer).

This tiny species faces many threats – also in our Biosphere Reserve. Invasive alien plants, development and pollution are a serious concern for our population of Micro Frogs. In fact, it’s likely our most threatened vertebrate species. Our Kogelberg Biosphere Reserve members (especially the Betty’s Bay Conservancy) are helping to monitor sightings of the frog, and report it to conservation authorities.

Above: Stream flowing from Luiperds Kloof in the Harold Porter National Botanical Garden. Image: LoveGreen Communications.

Frogs photographed by bioblitzers

During the recent 2022 City Nature Challenge (CNC), which took place between 29 April and 2 May, our Overstrand bioblitzers (citizen scientists) were out in force to photograph all of nature over one long weekend. While the Micro Frog evaded our hard-working CNC participants (the frogs will only pop up to start breeding in a few months’ time), a number of other frog species were caught on camera.

Here are some of the frog species seen and heard during the CNC:

– Clicking Stream Frog, or Gray’s Stream Frog (Strongylopus grayii): A species that’s endemic to South Africa.

– Cape River Frog (Amietia fuscigula): It’s also endemic to South Africa, only occurring in the Western and Eastern Cape.

– Southern Dainty Frog (Cacosternum australis): It’s a species listed as Least Concern on the IUCN Red List, but is still endemic to South Africa.

Audio: @flamelily, iNaturalist

Image: Cape River Frog, Amietia fuscigula @corli, iNaturalist

Image: Arumlily Reed Frog, Hyperolius horstockii @eli_g, iNaturalist

Image: Clicking Stream Frog, Strongylopus grayii @kokkelollie, iNaturalist

Image: Cape River Frog, Amietia fuscigula @melinda185, iNaturalist

Image: Raucous Toad, Sclerophrys capensis @kevinspiby, iNaturalist

Image: Cape River Frog, Amietia fuscigula @bb_van_zyl, iNaturalist

Our region came 13th in the world

These frog species helped contribute to the incredible performance of the Overstrand district in the City Nature Challenge. Our region came 13th in the world, with just short of 20 000 observations, and 16th globally in terms of species observed, (with 2 316 species). An incredible 259 people got involved over the course of the weekend in the Overstrand.

FROG SPECIES

There are over 5 000 species of frogs in the world, they are found on every continent except Antarctica.

More fun frog facts:

  • Frogs do not need to drink water – they absorb water through their skin.
  • Frogs come in all sorts of colours, the colourful skin of many tropical frogs acts as a warning to predators that these frogs are poisonous.
  • Frogs have excellent night vision and are very sensitive to movement. The bulging eyes of most frogs allow them to see in front, to the sides, and partially behind them.
  • Like all amphibians, frogs are cold-blooded; which means their body temperatures change with the temperature of their surroundings. When temperatures drop, some frogs dig burrows underground or in the mud at the bottom of ponds. They hibernate in these burrows until spring.
  • A group of frogs is called an army – mimicking an army, large groups of frogs come together during the breeding season to search for food. Moving in a large group provides frogs who would otherwise be vulnerable traveling alone, with an increased chance of survival.
  • Frogs can’t eat and keep their eyes open at the same time. The anatomy of a frog doesn’t allow it to keep its eyes open and swallow prey at the same time. The eyes help push the food down the frog’s throat.

Left: Small river in the Harold Porter National Botanical Garden. Image: LoveGreen Communications. Middle: Southern Dainty Frog, Cacosternum australis. Image: @david_taylor, iNaturalist. Right: Painted Reed Frog, Hyperolius marmoratus. Image: @linki, iNaturalist.

Sources:
Your place in the Kogelberg, by Tim Attwell
The Kogelberg Biosphere Reserve March 2022 newsletter

 LATEST NEWS

How wildfire impacts on our water

How wildfire impacts on our water

Once a wildfire is extinguished, you may think that it’s the end of the fire. But the impact on biodiversity and ecosystem services will continue to play out for a long time to come. Fire, for example has the

Hiking in the Kogelberg Biosphere Reserve

Hiking in the Kogelberg Biosphere Reserve

Whether you live in the Kogelberg Biosphere Reserve, or are visiting for a while, you’re in for a hiking treat. There are many fantastic hiking trails to choose from, deep in the mountains or down at the coast.

Biosphere Living

If you live in the Kogelberg Biosphere Reserve region, you’re already enjoying Biosphere Life. That means you can already enjoy all that Mother Nature offers you here, in this incredibly special part of the world.

 

You can take the next step, to become even more involved in the Kogelberg Biosphere Reserve.

And remember to include us in your social media posts, by using the hashtag: #BiosphereLiving.