Drylands Conservation Programme

Population Demography Research

Demography Project
This cryptic species’ small size, and solitary and nocturnal behaviour, coupled with the fact that it occurs in dense vegetation with low visibility, presents a unique range of challenges to biologists studying them. Studies done in the past have yielded estimates of 500 to 1435 individuals; however, exact figures for Riverine Rabbit populations are not available. The current Riverine Rabbit distribution range is based the results of surveys carried out on foot in cooperation with the relevant provincial conservation authorities. The distribution data base also includes ad hoc sightings data on farms and from the general public.

Determining population densities and trends, however, requires a whole different approach. In March 2012, the RRP initiated a study into the application of camera traps to determine Riverine Rabbit densities. Camera traps have been used extensively on other species, primarily patterned carnivores, but not extensively on Lagomorphs. Please see our NEWS page for more information.

Genetics
Slight genetic variations exists between the northern (Nama Karoo) and southern (Succulent Karoo) Riverine Rabbit populations. Since the 2003 discovery of populations of Riverine Rabbits in the Western Cape (Touwsrivier, Montagu, Barrydale, Robertson and Klaarstroom) conservation efforts have been focused on learning more about this population and its association with the more well-known northern population. DNA samples (hair, skin) are primarily collected from roadkills and opportunistic captures. These samples are sent to the University of Stellenbosch (Evolutionary Genomics Group, Department of Botany and Zoology) for genetic analyses.

RIVERINE RABBIT POPULATION DEMOGRAPHY RESEARCH

The Riverine Rabbit’s small size and nocturnal behaviour, coupled with the fact that it occurs in dense vegetation with low visibility, represents a unique challenge to biologists and conservationists working on this species. Studies done previously estimated that there are about 500 to 1400 individuals left in the wild; however, exact figures for Riverine Rabbit populations are not available. The current Riverine Rabbit distribution range is based on the results of surveys carried out on foot in cooperation with relevant provincial conservation authorities. The distribution data base also includes ad hoc sightings data on farms and from the general public.

Determining population densities and trends, however, requires a whole different approach. Therefore in March 2012, the EWT-DCP initiated a study into the application of camera traps to determine Riverine Rabbit presence. As these camera traps showed surprising success in detecting Riverine Rabbits, we raised funds for 30 camera traps and a student from the University of Cape Town is currently developing a protocol for a scientific census technique for this rare and elusive species. This will add tremendous value to informing our conservation strategies for the species. Please see our NEWS page for more information.