A quarter century of annual Cape Parrot censuses: Current population trends and conservation imperatives

The endemic Cape Parrot (Poicephalus robustus) has experienced a dramatic decline in South Africa since the early 1900s, with only an estimated 1000–1500 individuals remaining in the wild. As a nomadic forest specialist, it moves between forest patches following fruit availability, particularly yellowwoods (Afrocarpus and Podocarpus spp.), making it challenging to accurately determine its population size and core distribution. To address this challenge, an annual Cape Parrot census day was initiated in 1998. Cape Parrot numbers have been monitored by simultaneous coordinated static counts at indigenous forests in all four of the genetically identified regional subpopulations in the Eastern Cape, KwaZulu-Natal and Limpopo provinces of South Africa, and at sites where the parrots are known to feed, such as pecan nut orchards. Census data and population trends from 2003 to 2023 (excluding 2020) are presented here. The largest population count of 1952 parrots was recorded in 2023. Age-class frequency distributions indicate that recruitment is ongoing in most Cape Parrot populations. Annual count data, analysed using dynamic population models (TRIM software), show a moderate but significant long-term increase in population size (per capita growth rate = 1.025 ± 0.006) from 2003 to 2023. Over the past decade (2013–2023), the population growth has stabilised (1.016 ± 0.013). Within each regional population, clusters or archipelagos of Afrotemperate forests (montane mistbelt and coastal temperate) that contain podocarp species and pecan nut (Carya illinoinensis) orchards are important for Cape Parrot metapopulation persistence. However, it is unclear how many discrete metapopulations are present. The need to conserve indigenous forests, particularly those with yellowwoods, is reinforced. Our findings demonstrate the value of citizen science for monitoring an endangered species.