@article{WasiolkaBlaumJeltschetal.2009,
  author    = {Wasiolka, Bernd and Blaum, Niels and Jeltsch, Florian and Henschel, Joh},
  title     = {Behavioural responses of the lizard "Pedioplanis l. lineoocellata" to overgrazing},
  issn      = {1146-609X},
  doi       = {10.1016/j.actao.2008.09.009},
  year      = {2009},
  abstract  = {We studied the effects of overgrazing on the foraging behaviour of the lizard Pedioplanis l. lineoocellata (Spotted Sand Lizard), a sit-and-wait forager, in habitats of differing vegetation states to determine the effects of habitat degradation on this species. At high grazing intensity where vegetation cover and diversity is low, the lizard P. lineoocellata moves more frequently, spends more time moving and covers larger distances than in habitats where vegetation cover and diversity is high. These behavioural changes in movement patterns can be explained by less abundant prey in habitats with low vegetation cover and diversity. Although morphology, phylogeny and physiology of P. lineoocellata should constrain the change in foraging behaviour, the species has modified its foraging strategy from sit- and-wait to actively foraging. We assume that this behavioural flexibility of P. lineoocellata is a buffer mechanism enabling the species to use and survive in degraded (unfavourable) habitats.},
  language  = {en}
}
@article{WasiolkaJeltschHenscheletal.2010,
  author    = {Wasiolka, Bernd and Jeltsch, Florian and Henschel, Joh and Blaum, Niels},
  title     = {Space use of the spotted sand lizard (Pedioplanis l. lineoocellata) under different degradation states},
  issn      = {0141-6707},
  doi       = {10.1111/j.1365-2028.2009.01085.x},
  year      = {2010},
  abstract  = {Although the effects of grazing-induced savannah degradation on animal diversity are well documented, knowledge of how they affect space use or responding behaviour remains poor. In this study, we analysed space use of the spotted sand lizard (Pedioplanis l. lineoocellata) in degraded versus nondegraded habitats of southern Kalahari savannah habitats. Lizards were radio tracked, daily movement distances recorded and home range sizes calculated. In degraded Kalahari savannah habitats where plant diversity and perennial grass cover are low but shrub cover high, P. lineoocellata moves larger distances (40.88 +/- 6.42 m versus 27.43 +/- 5.08 m) and occupies larger home ranges (646.64 +/- 244.84 m(2) versus 209.15 +/- 109.84 m(2)) than in nondegraded habitats (high plant diversity, high perennial grass cover and low shrub cover). We assume that this increase in daily movement distances and home range sizes is a behavioural plasticity to limited food resources in degraded savannah habitats. Although P. lineoocellata is able to adjust to resource-poor savannah habitats, the increase in the lizard's movement activities is likely to result in a higher predation risk. This is supported by the lower availability of protective vegetation i.e. perennial grass cover. Hence, we conclude that despite behavioural plasticity of P. lineoocellata, overgrazing has a severe negative impact on the space use of P. lineoocellata.},
  language  = {en}
}