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Great Southern BioBlitz 2021 – Overstrand

Updated: Jan 23, 2022

The idea behind the Great Sothern BioBlitz was to encourage citizen scientists, using the iNaturalist platform, to spend four days in nature observing and documenting plants, animals and fungi as a way to showcase the biodiversity of an area. Local areas spanning the three southern hemisphere continents took part over 4 days (22 – 25 October 2021). 184 312 observations by 5, 845 people were done and 21, 175 species were identified by 3 316 identifiers. This is an amazing testament to both the organisers and the everyday citizen scientist who contributed to this fun, yet critical initiative, to map biodiversity.


For all results check out our "Results Page"

Overstrand was enthusiastically signed up by Sandy Immelman (Betty’s Bay Conservancy) with the help of Dr Tony Rebelo (South African National Biodiversity Institute). Sandy promptly invited Tim Attwell (Kogelberg Botanical Society) as well as Magriet Brink and Jenny Parsons who are both members of the Kogelberg CREW (Custodians of Rare and Endangered Wildflowers) on board - and the rest is history.

Rupert Koopman (Conservation Manager: Botanical Society of South Africa) and Ismail Ebrahim (Project Manager of CREW CFR, SANBI) were enthusiastic to help Overstrand and brought much-needed expertise to this project. Tutorials were run on how to sign up for iNaturalist and on various important aspects of making observations, uploading and identifying them. So, the stage was set for what was an interesting and exciting four days of bioblitzing.

After much strategizing, it fell to everyone to use their networks and social media to spread the word about this unique event. Taylum Meyer (The Village NEWS, an independent newspaper in Hermanus) offered her skills and contacts to run with the media. Approaches were made to a number of organisations and individuals to come on board. These included Brenda Walters (Marine Dynamics and Dyer Island Conservation) for the marine biodiversity, which the ‘whale coast’ is renowned for; Dr Anton Odendaal (Birdlife Overberg) to encourage the local birders to join the blitz; Dr Di Marais (Hermanus Botanical Society) who showcased just how special and diverse the Fernkloof Nature Reserve in Hermanus is and likewise, Dr Chris Whitehouse (Phillipskop Mountain Reserve) shared just how biodiverse the area near Stanford is.

Learn more about iNaturalist with the BotSoc / CREW Webinar: Citizen Science: iNaturalist and the City Nature Challenge

The Kogelberg Botanical Society and Betty’s Bay Conservancy held iNaturalist workshops, Magriet ran iNaturalist tutorials for folk wanting more insight - and these initiatives complemented the CREW Team’s sessions advertised by the Botanical Society of South Africa on how to join and become a citizen scientist on the iNaturalist platform. Members of the Betty’s Bay Conservancy, together with nature enthusiasts from across the Overstrand, joined the project, some having never used iNaturalist before this BioBlitz. Folk from neighbouring towns such as Somerset West and Cape Town (Helen Pickering, Carina Lochner, Corrie du Toit and many others) made significant contributions and helped us with our quest.

Astrid Twomey, Sandy and Grant Immleman - novice iNaturalists in the Kogelberg

An exciting initiative was born in Kleinmond where various groups including the Kleinmond Nature Conservation Society, Kleinmond Fynbos FaceBook group, the Overberg Eco-Rangers and the Strandloper youth organisation were taken on a field trip to introduce iNaturalist and to demonstrate citizen science in action. This was hosted by Carl Swart, Rupert Koopman, Magriet Brink and Jenny Parsons together with parents and even the local Ward Councillor, Grant Cohen, attended. This is a project we hope to nurture and continue as these young naturalists are the future of conservation. We would like to include Harold Porter National Botanical Garden and the Kogelberg Biosphere Nature Reserve (Cape Nature) as partners in this venture going forward.


Strandlopers prepping for their outing in Kleinmond


Ultimately there were 176 participants who made a total of 14 331 observations and 433 individuals helped to identify 2 093 species. This meant that Overstrand arrived on the BioBlitz global stage with a bang - coming only second to Cape Town in the southern hemisphere. A phenomenal effort from all involved but a special mention must be made of Sandy Immelman who was instrumental in managing and driving the administrative side, while encouraging us to share the project far and wide.


Sandy Immelman of Team Overstrand, investigating some of the amazing local biodiversity


While we know we are privileged to live in a globally recognised biodiversity hotspot it is only when one starts analysing the projects statistics that this becomes apparent. The flora and fauna endemism together with the number of Red-listed species seen over the four days were testament as to why the fynbos environment is both special, but also under threat from habitat destruction, alien vegetation infestation and ultimately climate change.

There were 907 observations made by 100 participants who recorded 158 red-listed species, this equates to close to 60 percent of the folk in the Overstrand seeing a threatened, endangered or rare species while bioblitzing. The majority of the red-listed species were flora in the family Proteaceae where the following were most observed:

1. Leucospermum (spps – L. cordifolium, L. oleifolium and L. prostratum)

2. Protea (spps – P. cordata, P. lepidocarpodendron and P. longifolia)

3. Serruria (spps – s. rubricaulis, s. elongata and s. adscendens)

4. Leucadendron (spps – L. coniferum, L. platyspermum and L. linifolium)

5. Spatalla (spps – S. curvifolia, S. racemosa and S. mollis)

Learn more about the Red List and check the status of these species.

The family Ericaceae followed next and some of the species seen were Erica thomae, E. plukenetii, E. calcareophila, E. aristata and E. karwyderi. Other families seen included Orchidaceae (Disa purperscens), Asteraceae (Metalasia lichtensteinii), Hyacinthaceae (Lachenalia peersii) and Penaceae (Sonderothamnus speciosus).

While the flora dominated, other red-listed species observed included 8 bird species (Cape Rockjumper, Greater Flamingo, African Penguin, Blue Crane, Cape Cormorant, Caspian Tern, African Marsh Harrier and the Black Harrier), 2 mammal species (Bontebok and Grey Rhebok) and 1 reptile (Cape Dwarf Chameleon). One area where observations were made was in the marine life but were not verified on iNaturalist.

To conclude - the Great Southern BioBlitz 2021 was a huge success - not only in mapping the Overstrand biodiversity (which is only second to our neighbour, Cape Town in the southern hemisphere rankings) but in encouraging citizen science to grow at grassroots. This was achieved by involving both local residents (who had never heard of iNaturalist) and local experts in the flora and fauna of the Cape Floral Region (the smallest of the six Floral Kingdoms of the world). A highlight was introducing the group of youths to nature through the Strandlopers and Eco Rangers programs and showing them that their enjoyment of nature can include being citizen scientists! Going forward, while we need to grow the number of observers and get more folk involved, we also need to get more observations identified. This is something that the Overstrand will work on. South Africa boasts a natural heritage like no other – however, continued education and awareness is all important in protecting our biodiversity for future generations.

Sincere thanks to all involved and we look forward to our next quest in the Global City Nature Challenge from the 29 April to 2 May 2022. Overstrand Team 2021

this report was written by Jenny Parsons of Team Overstrand (above)


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