South Africa’s Forest biome is the smallest biome within the country, covering less than 0,25% of the country’s land surface. This biome is classified as one of the most vulnerable biomes on the sub-continent due to its high level of fragmentation and small extent of occurrence. The beautiful Afro-temperate forests that occur within the Southern Cape region make up a large portion of this percentage. As Nature’s Valley occurs in the heart of this region and is surrounded by a large expanse of beautiful indigenous forest, Nature’s Valley Trust has established a forest programme.
This programme is aimed at researching, conserving and restoring the Southern Cape Afro-temperate Forests that occur in the Tsitsikamma section of the Garden Route National Park (GRNP), especially in areas that fall outside the protected area. The programme activities are enacted at the newly declared Hebron Private Nature Reserve (PNR) where NVT staff are conducting various biodiversity assessments as well as managing the reserve.
Bird species diversity
Passive acoustic monitoring devices, Audiomoths, have been set up across Hebron PNR. These devices are used to document the presence of bird species within the Southern Cape Afro-temperate forests of the Southern Cape region. Along with Kaleidoscope, an audio processing software, NVT will be able to identify, code, and analyse the data that has been captured. Kaleidoscope will also be able to document variables such as the time of the day when birds call, the frequency of their calls and the weather conditions under which the birds call the most.
Photo credit: William Mann
Systematic ecological surveys are currently being carried out across Hebron PNR. These surveys aim to determine the diversity of vegetation, the health and the successional state of the Southern Cape Afro-temperate forests found within the Tsitsikamma section of the GRNP.
Surveys are being carried out in parts of the reserve with high disturbance compared to minimally disturbed areas. Ecological surveying methods such as quadrats and transect lines are used within this study. Aspects of vegetation measured, include; species presence, abundance and diversity, growth phase (seedling, sapling, pole or a mature tree), Diameter at Breast Height (DBH), height, canopy diameter, health, % of invasive vegetation present, % of indigenous vegetation present, % of planted vegetation as well as % of open ground.
Data collected from these surveys will allow us to have insight into the diversity, health and successional state of the Southern Cape Afro-temperate Forests occurring in the area.
Photo credit: William Mann
Fixed Point Photography
Fixed Point Photography is an easy and effective technique of using photographic images to monitor changes in the environment over time. Twenty-one Fixed Point Photography (FPP) sites were set up across the Hebron PNR to observe the various ecological processes occurring within a forest ecosystem. The plots are located throughout the forest, in areas that best represent the ecological processes that occur within a Southern Afro-temperate Forest, e.g. gaps that occurred in the forest canopy; sites at which alien invasive species (Australian Blackwood (Acacia melanoxylon) and Wandering Jew (Tradescantia zebrina)), had previously been removed; decomposing wood piles; tree fall sites; known bushpig feeding sites; exposed tree roots; and along a seasonally flowing stream bed.
At each site, GPS coordinates were captured, and pieces of rebar were placed into the ground, serving as physical markers for capturing a fixed-frame image of the site over independent visits. Each time an image was captured, the date, time and weather conditions were recorded, providing extra information about the conditions in which the image was captured.
Images will be taken every four months to document some of the changes that occur within the forest environment.
Impacts on mammal behaviour
The effects of anthropogenic activities on the occurrence and behavioural patterns of large mammals occurring within Southern Cape Afro-temperate forests are largely understudied. With Hebron PNR being surrounded by human developments such as cattle farmlands and small holdings, it is possible that these high levels of activity could alter the occurrence and behaviour of certain large mammals within the reserve. We are exploring the impact, if any, human activity has on the diversity and behaviour of the larger mammals that occur within the Southern Cape Afro-temperate forests.
Camera traps are being used to observe the diversity and movement of the larger mammals within these forests and how human activity affects their behaviour. Camera traps are being placed within the reserve to capture animal activity along man-made paths compared to animal trails. Images obtained from the camera traps are being processed via Trap Tagger, an artificial intelligence software for processing images.
This research will help guide management practices of human activity within small-scale forest reserves.
Baboon behavioural studies
Future projects include:
- Strategic management of alien invasive species.
- Impact of global warming on the growth of Black Ironwood (Olea capensis capensis) in the Southern Cape Afro-temperate forests.
- Linking forest patches to create functioning corridors.
- Restoration and expansion of forest patches that are not protected.