How do you control invasive species on private land?

Jonathan Bell is conducting field work for his MSc. In the first chapter, Jonathan is asking how it is possible to get access into private property in order to control invasive species. To do this, Jonanthan has been out and about asking people all over Cape Town to answer a questionnaire. 

In order to achieve a complete picture, Jonanthan is travelling to all areas of the city to ask everyone his questions.

It will be fascinating to find out how people from different areas of Cape Town feel about the control of invasive species on their private property. We are really looking forward to seeing the results.

In the second chapter, Jonathan is trying to find out the conditions under which contractors can maximise catching invasive species. In this chapter, he is interested in control of the invasive Guttural Toad. He has enlisted the help of contractors who are actively removing these animals from Cape Town properties. Jonathan has annual training sessions to have contractors collect data that he can use in his models. 

The toad team with their clipboards collecting toads and data for Jonathan's study.

The time to collection of each toad is noted together with the exact location and variables associated with the property on which the toads are found.

Using this data, Jonathan will be able to predict the exact conditions under which toads are most likely to be collected. This will maximize the value of the eradication campaign. 

Now a Zoology Section Editor at PeerJ

I've been an academic editor with PeerJ for 10 years, and I've handled over 70 papers in that time. Last month I was contacted by the PeerJ staff to ask whether I would join the team of Section Editors for Zoology at PeerJ. Each subject section has a small group of section editors who oversee the decisions made by the editorial board members. This ensures that there is some consistency and accountability for the decisions made by lots of independent editors. 

Far from being a passive role, the Section Editors engage in regular discussions about individual papers. It's a great opportunity to support the editorial board and authors alike. 

Now read the blog post or PeerJ.

GAA2 provides a whole lot of international and regional interest from the media

As might be expected from a global update published in Nature, results from the the GAA2 have produced a lot of media interest both nationally and internationally. Here are some of the ones from southern Africa.

Stellenbosch researcher contributes to critical global study on amphibians (capetownetc.com)

SU researcher part of global study on extinction of amphibians (iol.co.za)

I was also interviewed by eNCA on the results of the paper. Watch the full coverage below:

The eNCA, a TV broadcasting company that covers the African continent, has previously taken an interest in the work of the MeaseyLab when they interviewed Nitya Mohanty. You can watch the interview in full on YouTube. You can see the blog post here.

Results from GAA2 suggest a continuing global amphibian decline 

In 2004, the first IUCN global assessment of amphibians revealed that they are the most threatened vertebrates on the planet. Published today is the paper summarising the second global assessment of the conservation status of amphibians (GAA2). IUCN red list Assessments took place of 8011 species of amphibians from all continents (except Antarctica). 

Readers of this blog will be familiar with the assessments that took place in southern Africa that were the subject of workshops in December 2009 andNovember 2015(which also resulted ina bookanda paperon the subsequent conservation strategy, see also blog postshere).

Sadly, the GAA2 still shows a continuing decline in the global conservation status of amphibians, with 41.0% of them falling into threatened categories of Vulnerable, Endangered or Critically Endangered. This is greater than the threatened categories for mammals (26.5%), reptiles (21.4%) and birds (12.9%).

While habitat destruction and change are still the greatest threat to the majority of threatened amphibians (impacting 93%), climate change and disease are now growing in their importance and impacting more species than in the first assessment. In particular, central and eastern Africa are new hotspots for disease, primarily implicating the chytrid fungus.

There is also good news suggesting that amphibians can benefit from concerted conservation efforts. These include dedicated conservation areas, removal of invasive species and reintroduction programmes.  

If you want to read more about GAA2, then please look at the open access paper: 

Luedtke, J.A. et al. (2023) Ongoing declines for the world’s amphibians in the face of emerging threats. Nature https://doi.org/10.1038/s41586-023-06578-4

Over the years, MeaseyLab members have worked on a large number of threatened amphibians in southern Africa (see Further Reading, below). Here are just a few of them:

Rough moss frog, Arthroleptella rugosa(Critically Endangered)

IUCN SSC Amphibian Specialist Group & South African Frog Re-assessment Group (SA-FRoG). 2016. Arthroleptella rugosa. The IUCN Red List of Threatened Species 2016: e.T174664A77162276. https://dx.doi.org/10.2305/IUCN.UK.2016-3.RLTS.T174664A77162276.en. Accessed on 04 October 2023.

The microfrog, Microbatrachella capensis(Critically Endangered)

IUCN SSC Amphibian Specialist Group & South African Frog Re-assessment Group (SA-FRoG). 2017.Microbatrachella capensis.The IUCN Red List of Threatened Species2017: e.T13318A77158116.https://dx.doi.org/10.2305/IUCN.UK.2017-2.RLTS.T13318A77158116.en. Accessed on 03 October 2023.

Rose's dwarf toadlet, Capensibufo rosei(Critically Endangered)

IUCN SSC Amphibian Specialist Group & South African Frog Re-assessment Group (SA-FRoG). 2017.Capensibufo rosei.The IUCN Red List of Threatened Species2017: e.T112716154A47759127.https://dx.doi.org/10.2305/IUCN.UK.2017-2.RLTS.T112716154A47759127.en. Accessed on 03 October 2023.

Cape clawed frog, Xenopus gilli(Endangered)

IUCN SSC Amphibian Specialist Group & South African Frog Re-assessment Group (SA-FRoG). 2017.Xenopus gilli.The IUCN Red List of Threatened Species2017: e.T23124A77164368.https://dx.doi.org/10.2305/IUCN.UK.2017-2.RLTS.T23124A77164368.en. Accessed on 03 October 2023.

Western leopard toad, Sclerophrys pantherinus(Endangered)

IUCN SSC Amphibian Specialist Group & South African Frog Re-assessment Group (SA-FRoG). 2016.Sclerophrys pantherina.The IUCN Red List of Threatened Species2016: e.T54723A77159333.https://dx.doi.org/10.2305/IUCN.UK.2016-3.RLTS.T54723A77159333.en. Accessed on 03 October 2023.

Further Reading:

Angus, O., Turner, A.A. & Measey, J. (2023) In a Rough Spot: Declines in Arthroleptella rugosa calling densities are explained by invasive pine trees. Austral Ecology48(3): 498-512. https://doi.org/10.1111/aec.13273

Channing, A., Measey, G.J., De Villiers, A.L., Turner, A.A. & Tolley, K.A. (2017) Taxonomy of the Capensibufo rosei group (Anura: Bufonidae) from South Africa. Zootaxa 4232(2): 282–292 https://doi.org/10.11646/zootaxa.4232.2.11 pdf

de Villiers, F.A., de Kock, M. & de Measey, G.J. (2016) Controlling the African clawed frog Xenopus laevis to conserve the Cape platanna Xenopus gilli in South Africa. Conservation Evidence 13, 17. pdf

Edwards, S, Tolley, KA & Measey, GJ (2017) Habitat characteristics influence the breeding of Rose's dwarf mountain toadlet Capensibufo rosei (Anura: Bufonidae) Herpetological Journal27: 287-298. pdf

Furman, B., Cauret, C., Colby, G., Measey, J. & Evans, B.J. (2017) Limited genomic consequences of hybridization between two African clawed frogs, Xenopus gilli and X. laevis (Anura: Pipidae). Scientific Reports 7(1):1091 https://doi.org/10.1038/s41598-017-01104-9 pdf

Luedtke, J.A., Chanson, J., Neam, K., Hobin, L., Maciel, A.O., Catenazzi, A., Borzée, A., Hamidy, A., Aowphol, A., Jean, A., Sosa-Bartuano, Á., Fong G., A., de Silva, A., Fouquet, A., Angulo, A., Kidov, A.A., Muñoz Saravia, A., Diesmos, A.C., Tominaga, A., Shrestha, B., Gratwicke, B., Tjaturadi, B., Martínez Rivera, C.C., Vásquez Almazán, C.R., Señaris, C., Chandramouli, S.R., Strüssmann, C., Cortez Fernández, C.F., Azat, C., Hoskin, C.J., Hilton-Taylor, C., Whyte, D.L., Gower, D.J., Olson, D.H., Cisneros-Heredia, D.F., Santana, D.J., Nagombi, E., Najafi-Majd, E., Quah, E.S.H., Bolaños, F., Xie, F., Brusquetti, F., Álvarez, F.S., Andreone, F., Glaw, F., Castañeda, F.E., Kraus, F., Parra-Olea, G., Chaves, G., Medina-Rangel, G.F., González-Durán, G., Ortega-Andrade, H.M., Machado, I.F., Das, I., Dias, I.R., Urbina-Cardona, J.N., Crnobrnja-Isailović, J., Yang, J.-H., Jianping, J., Wangyal, J.T., Rowley, J.J.L., Measey, J., Vasudevan, K., Chan, K.O., Gururaja, K.V., Ovaska, K., Warr, L.C., Canseco-Márquez, L., Toledo, L.F., Díaz, L.M., Khan, M.M.H., Meegaskumbura, M., Acevedo, M.E., Napoli, M.F., Ponce, M.A., Vaira, M., Lampo, M., Yánez-Muñoz, M.H., Scherz, M.D., Rödel, M.-O., Matsui, M., Fildor, M., Kusrini, M.D., Ahmed, M.F., Rais, M., Kouamé, N.G., García, N., Gonwouo, N.L., Burrowes, P.A., Imbun, P.Y., Wagner, P., Kok, P.J.R., Joglar, R.L., Auguste, R.J., Brandão, R.A., Ibáñez, R., von May, R., Hedges, S.B., Biju, S.D., Ganesh, S.R., Wren, S., Das, S., Flechas, S.V., Ashpole, S.L., Robleto-Hernández, S.J., Loader, S.P., Incháustegui, S.J., Garg, S., Phimmachak, S., Richards, S.J., Slimani, T., Osborne-Naikatini, T., Abreu-Jardim, T.P.F., Condez, T.H., De Carvalho, T.R., Cutajar, T.P., Pierson, T.W., Nguyen, T.Q., Kaya, U., Yuan, Z., Long, B., Langhammer, P., Stuart, S.N., 2023. Ongoing declines for the world’s amphibians in the face of emerging threats. Nature 1–7. https://doi.org/10.1038/s41586-023-06578-4

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

Measey, J., Becker, F. & Tolley, K.A. (2021) After the fire: assessing the microhabitat of Capensibufo rosei (Hewitt, 1926). Herpetology Notes14: 169-175. pdf

Tolley, K.A., De Villiers, A.L., Cherry, M.I., & Measey, G.J. 2010. Isolation and high genetic diversity in dwarf mountain toads (Capensibufo) from South Africa. Biological Journal of the Linnean Society 100, 822-834. https://doi.org/10.1111/j.1095-8312.2010.01469.x pdf

Vogt, S., de Villiers, F.A., Ihlow, F., Rödder, D. & Measey, J. (2017) Competition and feeding ecology in two sympatric Xenopus species (Anura: Pipidae). PeerJ5:e3130; DOI 10.7717/peerj.3130 pdf

Dan van Blerk's study on Ghost Frog tadpoles is published

Readers of this blog will know that Dan van Blerk spent an entire summer season out in the streams of the Western Cape catching alien fish and Ghost frog tadpoles. If you've already forgotten see here and here.

Now Dan's first chapter of his MSc is published

This study shows unequivocally that invasive fishes have a negative impact on Ghost Frog tadpole abundance, something that we only knew before from anecdotal studies. Dan went to 111 sites across 26 streams finding that tadpole abundance decreases by around 18 times in the presence of invasive fish species.

The other thing that Dan uncovered is the real lack of data on the distribution of invasive fish in streams of the fynbos. This meant that they were absent from places where he thought they would be present and present in places where he thought they would be absent. 

This publication will be important in adding evidence for conservation decisions on the removal of invasive fishes from streams in the fynbos.

Van Blerk, D., Melotto, A., Pegg, J., Measey, J. (2023) Invasive fishes negatively impact ghost frog tadpole abundance. BioInvasions Records 12(4): 1121-1138. https://doi.org/10.3391/bir.2023.12.4.24 pdf