A joint meeting of the Herpetological Association of Africa and the African Amphibian Working Group in Wilderness, South Africa: 26 – 29 November 2024

Each of these groups usually meets every two years separately, so it was for the first time in their existance that they met in back-to-back meetings in Wilderness South Africa. First up was the 20th meeting of the AAWG, with plenty of familiar faces from across the globe. 

Next was the 16th meeting of the HAA, which also had great representation and considerably more delegates. 

The meeting featured presenters from 9 different African countries: Madagascar, Nigeria, Tanzania, Uganda, Ethiopia, Kenya, Ghana, Namibia and South Africa. This was certainly the best representation of the continent since each of the meetings started. 

The following talks featured MeaseyLab members:

Home and away: the gut microbiome of Xenopus laevis in native and invasive populations

John Measey; Jiankun Yu; Dareen Almojil; Stephane Boissinot; Laurie Araspin; Carla Wagener; Greg Pauly; Reed Ojala-Barbour; Claudio Soto-Azat

The vertebrate gut microbiome is a community largely composed of bacterial, fungal and viral components, whose molecular component equal that of the host. The influence of the microbiome is known to be significant both on an individual basis, and also on population scales in a wide range of host organisms. The gut microbiome is known to be involved with key attributes of animal health, including assimilation of nutrients, immuno-defensive functions and host behaviour. In this study, we used bacterial 16S rRNA amplicon-based sequencing for metataxonomic classification of the gut microbiome of individuals from 12 native populations of Xenopus laevis. These populations were selected to represent the native range of the host species. From the 16S rRNA community profiles, we determine the components of the core microbiome of X. laevis and ask whether deviations from the core are associated with the environmental context in which they live. In addition, we sampled populations from Chile (4) and USA (7) to determine what aspects of the core microbiome are retained by non-native populations. This represents the first time that the microbiome of X. laevis has been assessed across such diverse conditions and provides data that will help understand the role played by the environment within this model organism.

Southern Africa Amphibian Red List Project – updated assessments for the region lead the GAA3

Jeanne Tarrant; Joshua Weeber; Oliver Angus; Adrian J. Armstrong; Ninda L. Baptista; Francois S. Becker; Rebecca M. Brunner; Werner Conradie; Louis H. du Preez; James Harvey; Adriaan Jordaan; Keir Lynch; John Measey; Mohlamatsane Mokhatla; Darren W. Pietersen; Fortunate M. Phaka; Jennifer Swanby; Krystal A. Tolley; Andrew A. Turner; Luke Verburgt

As the most threatened vertebrate class on earth, amphibians are leading the biodiversity extinction crisis. The 2nd Global Amphibian Assessment (GAA2) found that 41.5% of species globally are at risk of extinction, these extraordinary and diverse creatures are experiencing the worst population declines and highest extinction risk of any vertebrate group. South Africa has a good history of updating Red List assessments and has done so consistently since 2004 with the publication of the Atlas and Red Data Book. As some of the first assessments to contribute to GAA3, regional updates are in process for 246 southern African amphibian species. A very high proportion (approximately 74%) are endemic to the region, emphasizing the need to understand their conservation status, and prioritize conservation resources. Over 150,000 records were collated from 16 institutions (including citizen science platforms) and numerous private collections. A team of twenty experts contributed to assessment updates, with the support of the IUCN Amphibian Red List Authority, Amphibian Arc, SANBI and Re:Wild. Applying the IUCN Red List criteria according to IUCN guidelines, the current assessments have resulted in category changes for over 40% of priority species, including assigning a status to all but one Data Deficient species and all Not Evaluated species. Future climate scenarios (2050s) were modelled for South Africa’s threatened frog species and predict a wide range of distributional impacts, which will be exacerbated by ongoing land-use change. 35% of threatened species are likely to be highly impacted by future climate change scenarios. The updated assessments will be published by IUCN in the first half of 2025, and the outcomes of this work will be invaluable in informing an updated conservation and research strategy, the National Biodiversity Assessment, and has already contributed to identifying species in need of urgent recovery in the next decade.

The BioSoundSCape project: Automating frog detection for ecological monitoring in the Cape Floristic Region

Andrew A. Turner; John Measey; Oliver Angus; Colleen Seymour; Alan Lee; Rose Snyder; Festus Adebgola; Leo Salas; Matt Clarke

Monitoring frogs has the potential to provide useful insights into measuring ecosystem health and the management of these ecosystems. Yet currently this monitoring is highly restricted, in space and time consuming. Data acquired from automated sound recording devices can extend the reach of ecological monitoring. The BioSCape project is a large, multi-party collaboration with NASA that aims to relate biodiversity patterns on the ground with remotely sensed, cutting edge spectral imaging that provides very high spectral resolution across the electromagnetic spectrum. One of the novel ways to measure biodiversity is to measure bioacoustic diversity. The BioSoundSCape project deployed a large number of automated sound recorders (AudioMoths) across the Cape Floristic Region and recorded nearly 1 million sound recordings. These recordings are freely available on NASA’s Distributed Active Archive Center. The project set up pattern matching algorithms to detect frog calls of 13 frog species, ran statistical pattern matching, validated results and used the resultant validated sound sonographic signatures for training input to a machine learning (computational neural network) system as implemented by RFCx in Arbimon. From this we calculated diversity indices and present examples of these outputs. Once the entire data collection, processing and analysis can be automated, it can realise the ability for large-scale, frog and ecosystem monitoring.

School for Climate Studies (SCS) and Centre for Invasion Biology (CIB) Annual Research Meeting

Regular readers of this blog will be familiar with the CIB-ARM which is hosted annually in November. This year (after a 2 year interim), we see the new SCS-CIB ARM: a joint venture where Masters and PhD students present on their latest research. This event provides an important forum for networking for post-docs and students alike. For the CIB, the entire Core Team is invited to come together with their students from universities up and down South Africa.

Policy from Science

This year, there was a promient flavour of policy from science both at the national and international level. Prof. Melodie McGeogh (Monash University) provided a plenary from her perspectives after participating in the recent IPBES report Thematic Assessment Report on Invasive Alien Species and their Control. 

In addition, Peter Lukey (Chief Director: Environment Knowledge and Information at DFFE) provided an overview of his experience as a policy maker in the South African government.

In addition to these plenary talks, we had a host of marvellous talks from postgraduate students from the SCS and CIB. This included Jonathan Bell who presented an update on his MSc work on improving the efficacy of the Gutteral Toad eradication programme.

Another great ARM from another year of research for 10s of students working on invasions and climate change. We look forward to next year when the intersection of these two disciplines will be dissected in more detail.

Laurie presents at the 22nd European Congress of Herpetology

The 22nd European Congress of Herpetology took place in Wolverhampton UK and Laurie Araspin presented her PhD work on Xenopus acclimation:

Locomotion and physiology depending on temperature in Xenopus laevis native and invasive populations
Araspin, L., Measey, J. & Herrel, A.

Ectothermic species are dependent on temperature, which drives many aspects of their
physiology. The distribution of native and invasive populations of the frog Xenopus laevis is
characterised by an exceptional latitudinal and altitudinal range. Along these gradients, the
thermal environment changes and populations experience different temperatures. We assessed
phenotypes depending on the temperature of individuals coming from six native and one invasive
populations. We measured the thermal dependence of locomotor performance in adults given its
relevance to dispersal, predator escape, and prey capture. Results show that the thermal
performance optimum differs among populations, and the minimum critical temperature varies
among populations coming from different altitudes. Then, we compared the standard metabolic
rate (energetic cost of organismal maintenance; SMR) depending on temperature, as locomotor
performance strongly relies on metabolic activity. We tested SMR in populations from the native
range, inhabiting low (South Africa) and high altitudes (Lesotho), and from the invasive range
(France). Regarding the contrasting climatic environments of the studied populations, differences
in the SMR depending on temperature are expected. We found that populations exhibit different
energetic costs in metabolic activity and that populations show reduced metabolic activity in the
temperature range the most encountered in their environment (i.e., in cold temperatures for
populations from colder environments and in hot temperatures for populations from warmer
environments). The ability of this species to change its optimal temperature for locomotor
performance and its metabolic activity across extremely different climatic environments may help
explain its invasive potential. These findings highlight the extraordinary thermal adaptation ability
of the species. This ability to cope with a wide range of variation in environmental temperatures
suggests that the species may be particularly good at invading novel climatic areas.

The 10th World Congress of Herpetology in Kuching, Sarawak, Malaysia

It was a great pleasure to attend the 10th World Congress of Herpetology in Kuching this month. The congress was a great opportunity to catch up with herpetologists from across the planet, including many that I have known for many years as well as many many new faces. 

I presented my work on the gut microbiome of Xenopus laevis, and was pleased to see many former members of the MeaseyLab presenting their own work. This included Max who presented work he conducted during his MSc on Scerophrys gutturalis. 

The first GAA3 meeting for Red Listing the amphibians of southern African 

The first Global Amphibian Assessment (GAA) took place in various workshops around the world from 1999 to 2002 (see Stuart et al 2004). I got involved by helping to assess the South African pipids while at University of the Western Cape (Measey 2004), and later at a workshop in Watamu, Kenya in April 2002.

I hosted the first re-assessment of South African amphibians in 2009, a process that incorporated the published strategy for conservation research on southern African amphibians. Together with other members of the workshop, we turned the results of this meeting into a book (Measey 2011), which I edited, and was published by SANBI in early 2011. The book is available as a free pdf to download, and you can get your own copy here. 

We repeated the Red Listing process again in November 2015 (see here) as well as appraising the results of the previous meeting (Measey et al. 2019), and these results were carried into the second Global Amphibian Assessment (GAA2), one of the outputs of which was published last year (see here) (Luedtke et al. 2023).

The assessments should be updated every five years, and so it was high time to do it again. This time we got together at the Calders Hotel in Fish Hoek.

It’s quite fun to see the faces in these images ageing. There has been a loss of a few of the older faces too. But the really great thing was to see the large number of new faces who brought with them some excellent expertise that amazed me. The workshop was hosted by Josh Weeber and current IUCN southern African Amphibian Specialist Group (IUCN-SSC) Chair Jeanne Tarrant.

This is officially the first workshop of the GAA3!

Although we spent four days solidly assessing the amphibians, we didn’t finish. Lots more work to do before we can submit the updates and have them published on the Red List site. Stay tuned for this update.

Further Reading:

Measey, G.J. (2004). The Genus Xenopus (Wagler 1827). In:  Atlas and Red Data Book of the Frogs ofSouth Africa, Lesotho and Swaziland, 258-259. Minter, L.R. et al. (eds). Washington DC: Smithsonian Institution Press. pdf

Measey, G.J. (ed.) (2011). Ensuring a Future for South Africa's Frogs: A Strategy for Conservation Research. Biodiversity Series 19. South African National Biodiversity Institute, Pretoria. pdf

Measey, J., Tarrant, J., Rebelo, A.D., Turner, A.A., Du Preez, L.H., Mokhatla, M.M., Conradie, W. (2019) Has strategic planning made a difference to amphibianconservation research in South Africa? African Biodiversity & Conservation - Bothalia   49(1), a2428. https://doi.org/10.4102/abc.v49i1.2428 pdf