A South African conservation group says 49 endangered vultures were electrocuted by power lines over the past weekend.

The Endangered Wildlife Trust said Wednesday the cape griffons were found at several locations in the Eastern Cape province, near a vulture feeding center.

The trust said vultures' wide wingspans, heavy bodies and "gregarious natures" make them vulnerable to tall man-made structures like power lines and wind turbines that stretch across vast, usually empty landscapes.

Spokeswoman Carla van Rooyen said about 200 vultures are killed by electrocutions or collisions each year.

The trust said South Africa's national power supplier, Eskom, has restructured towers in areas with high vulture populations, but towers built before the 1990s remain dangerous to the birds. Vulture conservation groups criticize the slow pace of redesigning these structures.