ASPECTS CONSERVATION BIOLOGY OF GREY CROWNED CRANE (Balearica reguloram, Bennet 1884) AT LAKE OL’ BOLOSSAT, KENYA

Abstract

The Grey Crowned Crane (GCC) (Balearica regulorum) belongs to the family Gruidae, which is among the most threatened of avian taxa due to pressure directed at their habitats. Their population is declining at an alarming rate, and it is listed as Endangered in the IUCN Red List of Threatened Species. Lake Ol’ Bolossat in Nyandarua County, Kenya, is a key stronghold for this species, holding the second largest population after western Kenya. This study was carried out between September 2016 and February 2017 to determine the population size, distribution, nesting success, and how human activities impact GCC in and around Lake Ol’ Bolossat, which are key strategies to effective conservation of GCC. Line transects were used to collect GCC count data, the Mayfield exposure method for nest data, while questionnaires were used to collect data on anthropogenic factors. Statistical analyses were conducted using R (version 4.3.0) and SPSS v25, while ArcGIS Pro V.3.3.3 was used for map preparations. An average of 315 GCC were observed per visit, representing a mean density of 3.15 birds/ha. Results showed that GCC were more concentrated in the farmland (1.40±0.24 individuals ha -1 ), intermediate in grasslands (0.90±0.22 individuals ha -1 ), and lowest in the wetlands (0.17±0.02 individuals ha -1 ). Fifteen nests were discovered with an average clutch size of 2.33 eggs/nest, which were monitored until the final nest fate was known. The overall nesting success was 20.72%. Nesting success in Lake Ol’ Bolossat was limited by habitat availability and habitat quality in addition to human-related threats, including egg collection and nest abandonment by breeding pairs. Human-mediated effects were not significant in the conservation of GCC exception of hunting, which was significantly different across the 11 villages. For successful conservation of GCC around Lake Ol’ Bolossat, good planning is essential to ensure the adoption and implementation of effective conservation programs targeting GCC; Lake Ol’ Bolossat and its surrounding habitats should be protected, and human access regulated to control resource exploitation and enhance its conservation. Since GCC breed during the rainy season, zoning off the breeding sites during the breeding season could help improve the chances of a successful nesting, alongside advancing strategies and programs that promote awareness on conservation while aiding initiatives pro conservation at the community level.