TY - JOUR
T1 - Quality of remnant indigenous grassland linkages for adult butterflies (Lepidoptera) in an afforested African landscape
AU - Pryke, Sarah R.
AU - Samways, Michael J.
PY - 2003/10/1
Y1 - 2003/10/1
N2 - Retention of interconnected, remnant grassland linkages is proposed here to reduce the adverse effects of alien pine afforestation in Afromontane grasslands. Adult butterflies were sampled at 38 grassland sites, representing increasing levels of disturbance both within the afforested area and outside it. Butterfly species richness and abundance in the lesser disturbed grassland remnants within the afforested area were similar to those of the surrounding natural grasslands. In contrast, butterfly species richness, but not necessarily abundance, decreased significantly in the highly disturbed sites, both in the grassland linkages and outside. Although some highly disturbed sites were relatively rich in species, most were visited by geographically widespread and vagile species. In contrast, wide, relatively undisturbed grassland linkages, as well as grasslands outside, were important for localised, sedentary and local endemic butterfly species. Nectar plants, especially the alien Verbena bonariensis, were the most significant variable explaining local butterfly distribution. In addition, tall grasses, hills, topographical landmarks, thermoregulatory sites, shelter and water features were also vital for particular species. It did not matter how deep the grassland linkages were situated inside the afforested area, as long as they were made up of good habitat. Retention of wide, quality grassland linkages are a way forward to maximise biodiversity alongside agroforestry.
AB - Retention of interconnected, remnant grassland linkages is proposed here to reduce the adverse effects of alien pine afforestation in Afromontane grasslands. Adult butterflies were sampled at 38 grassland sites, representing increasing levels of disturbance both within the afforested area and outside it. Butterfly species richness and abundance in the lesser disturbed grassland remnants within the afforested area were similar to those of the surrounding natural grasslands. In contrast, butterfly species richness, but not necessarily abundance, decreased significantly in the highly disturbed sites, both in the grassland linkages and outside. Although some highly disturbed sites were relatively rich in species, most were visited by geographically widespread and vagile species. In contrast, wide, relatively undisturbed grassland linkages, as well as grasslands outside, were important for localised, sedentary and local endemic butterfly species. Nectar plants, especially the alien Verbena bonariensis, were the most significant variable explaining local butterfly distribution. In addition, tall grasses, hills, topographical landmarks, thermoregulatory sites, shelter and water features were also vital for particular species. It did not matter how deep the grassland linkages were situated inside the afforested area, as long as they were made up of good habitat. Retention of wide, quality grassland linkages are a way forward to maximise biodiversity alongside agroforestry.
KW - Afforestation
KW - Africa
KW - Butterflies
KW - Grassland remnants
KW - Linkages
UR - http://www.scopus.com/inward/record.url?scp=0037523333&partnerID=8YFLogxK
U2 - 10.1023/A:1024103527611
DO - 10.1023/A:1024103527611
M3 - Article
AN - SCOPUS:0037523333
SN - 0960-3115
VL - 12
SP - 1985
EP - 2004
JO - Biodiversity and Conservation
JF - Biodiversity and Conservation
IS - 10
ER -