Movement patterns of grey crowned cranes balearica regurolum across Rwandan borders

Abstract

Grey Crowned Crane (Balearica regulorum), a resident of East and southern African regions, is of global conservation concern as it is classified as an endangered species according to IUCN Red List of threatened species with a decreasing population. Cranes undertake seasonal movements, while their cross-boundary movements are less studied. This study assessed the movement patterns of Grey Crowned Cranes across Rwandan borders and the environmental patterns that may influence their movement. At three sites in Rwanda (Nyagatare, Akagera National Park and Akanyaru), ten Grey Crowned Cranes were tagged with GPS-GSM by the Rwanda Wildlife Conservation Association (RWCA) to record individual GPS coordinates and other environmental factors. Home range estimated with the 95% kernel density estimation (KDE) method was 3048km2 in the short dry season; 3017 km2 in the long rainy season; 2241 km2 in the long dry season and 2707 km2 in the short rainy season. Cropland, wetland and temperature were the main environmental factors influencing the cross-border movement of Grey Crowned Cranes. Wetlands were used in the rainy season for breeding and feeding while cropland was used by Grey Crowned cranes during the dry season. This study provides the first estimates of home range size and crossborder movement parameters for Grey Crowned Cranes from Rwanda to Burundi, Tanzania and Uganda and documents their habitat suitability and seasonal variations. These results are valuable for supporting trans-boundary collaboration in protection and restoration of the habitats for these endangered bird species.