# General Topics > Fieldwork >  Giant Bullfrog (Pyxicephalus adspersus) road cruise and release

## Buck Rogers

Date: 27th October 2012
Time: 8 - 10pm
Temp: 16°C
Location: Johannesburg, South Africa
Rainfall: <50mm 

Firstly, sorry for taking so long to get this posted, especially to John Clare.

On the 27th October 2012 we had a day of nice heavy rainfall that came down non-stop for a few hours. I have now learnt that when we have this kind of Highveld rainfall (usually <50mm) there will be lots of flooding and lots of Bull Frogs. Just to clear this up from the start these are _Pyxicephalus adspersus_, the Giant Bullfrog. So at around 8 o'clock in the evening I got in my car and faced some serious winds (which blew a sign board across the road and dented my number plate and bumper). I took a route which I will not disclose in a public forum, I drove about 30km on this trip and came across well over 20 Bull Frogs ranging from 9cm in size and the largest one I saw was well over 20cm. Unfortunately this road that I took was a very busy road, and many of these frogs were killed on the roads. 

I take these trips specifically to catch and release in safer areas and off of main roads. Not all the frogs can be saved as it is quite dangerous to pull your car over in rainy weather (specially because there are no street lights on this stretch) and then run across the road trying to catch a disgruntled frog who just want to get to the breeding holes.

So these were two that I brought home to release in a pan close to my house, both as you can see in the first pic and second pic, measured in at around 10-11cm






The next day I released at the pan near my house, these are a few pics of what a general breeding pan will look like:




As you can see in these 2 pics the soil is very hard and grassy with different kinds of veld (field) grasses, this helps the water gather and develop water pans.




But when the rainy season starts you need gum boots to get around these pans.



I came across these tadpoles in the pans. At first I thought they were Bull Frog tadpoles, I still am not sure. They probably are one of our indigenous toad species but the way the tadpoles were behaving threw me off - usually tadpoles from our toads gather in a large ball and are in very deep waters, these were in shallow waters. Some clarity would be helpful.





And one final pic, I came across thise little guy sitting on the side of the road a few weeks back on the way to the local convenience store at around 8pm at night.




Hope you find these pictures interesting and feel free to ask me any questions except the locations of where I found the frogs.
Also please note all frogs have been released safely and hopefully will breed in the wild next season in a safer area.

Darryn Rogers

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## DeeDub

This is very awesome! I do the same with the Wood house's toads in my area. Don't see a whole lot of them anymore. This year I'll get pics. Thanks for sharing.

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## Wicked frogs

awesome.

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## Terry

Hi Darryn,

Nice photos and great field work. Good to see you back on the forum!

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## Rupert

How big do Giant Bullfrog tadpoles get?

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## Jerah Teoh Yong Qiang

I do the same for the Asian Toads I come across in my area! It's really nice to see someone care for the animals in their area as much as you do! 

Great job!

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## Gorgonopsia

Hi Darryn. Thanks for show us your photos, and also thanks for telling the stories of your searching days.

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## Buck Rogers

Hi guys

I wanted to update this with some information about the winters here in the highveld to help you guys with hibernating your Pixies. We generally have dry, icy winters, but this one was very odd. Our Winters really start May and start warming up around mid to late August, temps range from -2 degrees Celsius and reach a maximum day time high of between 12-18 degrees Celsius. From May the temps will start dropping in the minimum range but day times high still stay in the high teens, by July we will experience very low minimum temps ranging from 0 - 8 and usually a week when they drop below zero. The humidity is on average 10 - 20% and frost is a very common site on early mornings. The actual air is dry and harsh, we hardly ever have winter rains but it is not uncommon as well as snow fall (which usually only lasts for a day before melting).

However this Winter was very different and comortable. We only had 2 days where the temperature dropped below zero and most of the winter was pleasant. We also experienced a day of heavy rain fall which is very uncommon and a warm front followed this. The other abnormality was the rain came from the North which is odd because if we do have Winter rains it will be blown up from the Cape - South West South Africa.

I took these pics on the 17th August at 1:07pm which would be the hottest point of the day. Mid August would be the coldest season in the Winter months, but the temps on this day were 18 degrees and dropped to 5 degrees that night. The point of these pics was to show how harsh and dry the same area as shown above would look in the middle of the Winter. Bearing in mind there underwater rivers which are very common in the Highveld and also because of all the strip mining in Johannesburg over the last 100 years there have been many underground caves created which collects a lot of water far below the surface. Usually if you dig deep in the soil it is still quite damp, which would be ideal for any hibernating amphibians.





From these pics you can see how all the water pans are completely dry and how all the grass is dead. These are semi-perennial water pans which is the ideal breeding ground for Pixies as well as many other South African wildlife. These pics are also really shocking because the area has been now used as a dumping ground because a lot of construction of housing estates have started to be developed in our area over the last year which obviously puts a huge strain on the Bullfrog's natural breeding grounds. However, the Highveld pretty much is one giant semi-perennial water pan so there are plenty of areas like this, but they are all prime locations for development as well as low cost housing and informal squatters. 

I hope this can be of some help to the Pixie keepers and you can expect me to update this thread in the next 2 months with some new finds in my new hunting grounds.

Darryn

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## Carlos

Thanks for original post and update Darryn!  Human encroachment and global heat (caused by us too) are the problems many earth species are presently facing.  Are there any signs the frogs you released near house back in 2012 still around?  Good luck  :Smile:  !

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## Hypnotic

Carlos, just this post alone earned you member of the week in my opinion.  :Wink:

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Mentat

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## Buck Rogers

> Thanks for original post and update Darryn!  Human encroachment and global heat (caused by us too) are the problems many earth species are presently facing.  Are there any signs the frogs you released near house back in 2012 still around?  Good luck  !


Its still too early in the season for Pixies - we still pretty much in Winter till September, although we are already experiencing fantastic weather. If you see the original date in 2012 that is when the activity really starts, the heavy rains need to trigger them into activity. I will post updates from October till February on this post updating everyone on the finds. Last season I could hear males calling close to my house, I just need to find where they calling from. But to be honest with all the development in my area I really think this will have greatly affected the population.

Will keep everyone posted.

Darryn

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## Buck Rogers

I came across this post on a local South African forum. For anyone who is interested in spawning pools and what they will look like. Usually there will only be one male that stays behind to guard all the tadpoles.
SAReptiles &bull; View topic - All Over Namibia

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## Buck Rogers

Date: 20th October 2013
Time: 7 - 8:45pm
Temp: 14°C
Location: Johannesburg, South Africa
Rainfall: +/- 24mm in 24 hours

We had our first consistent rainfall from Saturday night to Sunday night and although it was not the most rain as compared to previous seasons, I took the opportunity and way to go on another road cruise. It was a less successful drive than previous years, as I only came across one lone Bullfrog and only saw one DOR (dead on road). I think the main contributor to this is that we have had hardly any rain this season. Last year we had scattered showers from September and then one solid 24 hour down pour, this season has been a very dry start. The one thing I noticed was there were a few Common Clawed Frogs (_Xenopus laevis) _ on the roads, which tells me that they were migrating to bigger pools which means there are very few water pans that have filled.

The one Bullfrog that I did find was quite big, roughly 20 cm (snout to vent) and was very lethargic, which could have been a result of the cold weather. You can see from the pics that he looks well fed but his hips were exposed and the fat was hanging low, which makes me think this specimen was recently out of hibernation.





In previous years I always though that the Bullfrogs were migrating, and they have to cross the road to get to bigger pans, but now I think that they are actually hunting. After the rains there were plenty of toads on the road either warming up or hunting insects. There were plenty King Crickets (_Libanasidus vittatus) _ on the road last night and I think this is what actually brings the Bullfrogs to the roads at night.

Here is a pic of one of the clawed frogs on the road:



I am hoping that I will hear some males calling from the breeding pool near my house that I can get some pics for you guys of this, but I really do doubt this will happen because we have had so much housing development in our area over winter, that I am sure most of the Bullfrogs have been killed or displaced.

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## Buck Rogers

Our summer rains came very late this year, and only in the last 2 weeks have we had our annual 24 hour rainfall session. This usually is when we have a solid 24 hours of heavy rains that usually exceed 50mm, and with this all the water holes/pans full and this is when the frogs go into crazy breeding mode. If I could only describe the noise that we've heard over the last few weeks it is incredible. At any given pond/damn/puddle there is life again, but my best was about a week ago while I was in the bath I heard the deep bellow of several male bullfrogs. I took a drive around my area and walked around that evening to try find the pan that they were all gathered in, but I think it was actually in someones property. We live in an area that was old farm land, and there were several pieces of land that were subdivided into smaller plots. A lot of these plots still have perennial water holes so it is impossible for me to actually get in there and find the breeding pools. I will however be exploring a few of the vacant/open land and see if I can find some tadpoles and hopefully some males guarding the tadpoles.

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