Invasive cannibal toads pose threat

A guttural toad, the invasive species.

The guttural toad, an alien toad species, is rapidly establishing itself and spreading; and it is causing havoc with the endangered western leopard toad.

Karen Gray Kilfoil of the Sun Valley Eco Watch says: “The guttural toad is the single biggest threat to local populations of the western leopard toad – it out-breeds them by 10 to one, and it is thought to cannibalise the leopard toad,” she says.

“Please report any suspected guttural toad breeding to the relevant authorities, and do not dispose of the toads your-
self.”

The City of Cape Town, in partnership with Cape Nature, the Centre of Excellence for Invasion Biology and the Natural Resources Management Programme need your help to gently, without harm, remove the alien toads.

The parties have embarked on a joint project to protect indigenous toads and frogs.

Guttural toads pose a serious threat to the survival of indigenous frog and toad species, especially the endangered western leopard toad because they compete for habitat, resources and breeding grounds.

The City of Cape Town, the South African National Biodiversity Institute (SANBI) and Cape Nature are currently busy with a project to manage the invasive guttural toad.

The City has stressed that, however good one’s intentions, removing toads, tadpoles or eggs from one’s property to other properties or water bodies could have potentially devastating ecological effects.

“It is important to follow a systematic approach in finding and making appropriate arrangements to remove the invasive toads from all properties in the breeding range and not miss out any potential breeding site as the population will continue to spread,” Ms Gray Kilfoil
said.

The guttural toads usually occur in a 5km range in the Constantia Valley area (north of Constantia Main Road) and are known to breed in garden ponds. However, the invaded area is increasing year after year and it is now possible to find this
species outside Constantia.

At the beginning of 2014 some guttural toads were detected for the first time in Bishopscourt. If this population spreads there is a very real threat of them colonising a much wider area in the City of Cape Town.

It is essential to capture every guttural toad sighted, because a single female can produce 20 000 eggs a season.

The following information can help you to easily distinguish the guttural toad from the western leopard toad.

Guttural Toad

By call: Deep, guttural, pulsed snore which resembels the bounces of a dropped ping-pong ball. Usually heard during breeding season which is September through to February.

Colour: Light to dark brown with pairs of darker brown patches, smaller scattered spots some-
times occur between the larger patches; brown line down the
back: sometimes between the
eyes; pale prominent cross
formed by two sets of dark brown patches.

Underside: Dirty white colour

Thighs: Red infusion

Western leopard toad

By call: Long drawn-out snore on overcast days. Often heard during breeding season in spring, usually August to October.

Colour: Striking symme-
trical dark red-brown markings, edged in black and yellow. They usually have a yellow line down
the back; and between the
eyes, a dark patch, not forming a cross.

Underside: Whitish colour

Thighs: No red infusion

If you find a guttural toad:

* Put it gently into a bucket or any other similar container. The container should have a lid, to prevent the toad from escaping, and it should be kept in a cool, darkish place.

* Write down where you found it.

* Contact NCC Environ-
mental Services at 021 702 2284, Jonathan Bell at 072 037 3034 or Graca De Abreu at 073 651 5456. You can also send an email to gutturaltoads@ncc-group.co.za or jonathanjab@ncc-group.co.za

The toad will be collected from you as soon as possible.