Urbanization affects frog communities at multiple scales in a rapidly developing African city
Date
2015Author
Kruger, Donnavan J.D.
Du Preez, Louis H.
Hamer, Andrew J.
Metadata
Show full item recordAbstract
Urbanization is worldwide among the biggest threats to amphibian populations.
However, hardly any studies have been conducted on the effects thereof in developing
countries. Amphibian distribution and community assemblages are not well understood in
aquatic and terrestrial habitats that are rapidly changing due to human modification. We
conducted four surveys using three detection methods for both anuran larvae and predatory
fish in 61 ponds in and around the city of Potchefstroom, South Africa. Tadpoles of eight
anuran species and seven fish species were detected during the field surveys. The common
river frog (Amietia quecketti) was the most abundant species, occurring in 39 % of the sites,
whereas the bubbling kassina (Kassina senegalensis) was detected in only one pond. The
remaining six species were detected in 6.6–26.2 % of the sites. Predatory fish were detected in
64 % of the wetlands with mosquitofish (Gambusia affinis) and the banded tilapia (Tilapia
sparrmanii) detected respectively in 44 and 43 % of the sites. High species richness was
associated with well-vegetated wetlands, low urban CBD surface area and conductivity, large
pond areas and steeper bank slopes. Conductivity and pH showed only weak negative effects
on species richness. This is the first study to quantify the effects of urbanization on frog
communities in a developing city on the African continent. Our results demonstrate that both
local and landscape variables affect amphibians in a small but rapidly developing city.
Accordingly, management practices need to adopt a multi-scale approach if we are to conserve
amphibians in African cities
URI
http://hdl.handle.net/10394/18810https://doi.org/10.1007/s11252-015-0443-y
https://link.springer.com/article/10.1007/s11252-015-0443-y