IUCN Red List Update: The Kings and Queens of the plant world are under threat

The most recent update of the International Union for the Conservation of Nature’s Red List has found that 45% of the striking protea family that includes the national flower of South Africa, the King Protea, are under threat of extinction. 637 of 1,464 species assessed were found to be Vulnerable, Endangered or Critically Endangered with a further 9 now believed to be extinct. The protea family grows all over the Southern Hemisphere reaching only as far north as the Caribbean, Japan and Southern China. Many Proteaceae species have highly restricted ranges, making them more vulnerable to the spread of invasive alien species, disease, changes to natural fire cycles linked to climate change and loss of habitat to agriculture. They are an ancient family of flowering plants known from fossils from a time before the extinction of the dinosaurs and form the backbone of the conservation we undertake at FossilPlants.

The family contains iconic plants often seen as cut flowers such as the national flower of South Africa, the King protea (Protea cynaroides), the Queen Protea (Protea magnifica), the Scarlet Banksia (Banksia coccinea) and the pincushion (Leucospermum cordifolium). The family also includes a range of plants important to people for their wood, seeds or their nectar.

A vibrant cultivar of Leucospermum cordifolium

A vibrant cultivar of Leucospermum cordifolium

With the publication of this Red List update, all South African proteas have been assessed for the IUCN for the first time and almost half (47%, 165 of 353 species) are threatened with extinction. The majority of South African proteas are found in the Cape floral kingdom, the smallest of the world’s six floral kingdoms, among the fynbos which is considered the most floristically diverse habitat on earth. The Fynbos holds an estimated 9,000 vascular plant species of which 69% are endemic. Invasive alien species such as introduced pines and Hakea (another member of the protea family) are the most significant threat having an impact on 48% of protea species in the region. Even those occurring in protected areas are threatened by invasive species and this combined with changes to natural fire cycles, disease and loss of habitat due to agricultural and urban development is causing rapid population declines.

Development around Cape Town has irreversibly degraded and destroyed over 85% of the habitat of the Critically Endangered Kraaifontein Spiderhead (Serruria furcellata), causing the population to decline by 99% in one generation; and only a single wild mature plant from the original population remains. There are an additional 38 Critically Endangered species of South African Proteaceae on the brink of extinction, where urgent reintroduction and habitat restoration actions are required to reverse declines.  With other species down to just a handful of individuals left in the wild the future looks bleak for some.

Overberg sandstone fynbos is one of the most floristically diverse habitats on earth

Overberg sandstone fynbos is one of the most floristically diverse habitats on earth

The elusive Mace Pagoda (Mimetes stokoei) has entered the IUCN Red List as Critically Endangered. Until 1969 it was thought to be extinct, yet this species was rediscovered after a wildfire in 1999.  Despite it being closely monitored for 87 years its current wild population stands at fewer than 10 individuals. 10 of the 13 species of Mimetes are threatened with extinction and many have proven difficult to grow from seed, we have been working hard with individuals in South Africa to understand their cultivation and we successfully reared plants of Mimetes arboreus (EN) from seed for the first time in 2016.

Mimetes hottentoticus. Mimetes is one of the genera being researched by the 'proteas With Altitude' project

Mimetes hottentoticus. Mimetes is one of the genera being researched by the ‘proteas With Altitude’ project

Some of the impacts of climate change may be obvious, with changes in temperature and rainfall likely to impact the plants directly, yet other impacts may be increased incidence of diseases such as Phytophthora cinnamomi, increased fire frequency and changes to the distribution and abundance of some weeds.

Whilst the greatest of threats are towards species of South African Proteaceae in the lowland areas of South Africa climate change is having an impact on those species found at higher altitudes. Many of the protea species listed as threatened in this recent Red List update make the mountains of the Cape their home with two of the four species of snow proteas (Protea cryophila (VU) and Protea pruinosa (EN)) being listed as threatened due the impacts of climate change affecting the tops of South Africa’s highest mountains. All four Snow Protea species are conserved as part of our project to understand the cultivation requirements of the high altitude members of the protea family.

Protea rupicola

Protea rupicola only grows near the summit of the Western Cape’s highest mountains

Australia’s Proteaceae species have been shown to be equally threatened. The protea family includes Macadamia from Queensland which provides us with edible nuts yet three species of Macadamia have entered the IUCN Red List as threatened with extinction in the wild. The Macadamia Nut (Macadamia integrifolia), which forms the bulk of commercial production, is listed as Vulnerable, with fewer than 1,000 mature plants left in the wild. The Rough-shelled Bush Nut (M. tetraphylla) and M. ternifolia are both assessed as Endangered. All three species have declined due to land clearing for agriculture, urban development and invasive species. It is anticipated that global warming will alter the distribution of their rain-forest homes and they are also likely to be further impacted by the effects of climate change.

Banksia is arguably one of Australia’s most iconic genera of plants and many species are newly listed as threatened as part of this update. FossilPlants holds the UK Plant Heritage National Collection® of South East Australian Banksia species and we have been working to better understand the germination and cultivation of Banksia saxicola (Vu) Red Listed again due to a combination of factors including climate change. We also hold ex-situ conservation collections of a number of other threatened Australian Proteaceae species including Banksia vincentia (CR); Australia’s most threatened Banksia species with a wild population in single figures, Banksia plagiocarpa (EN) and Banksia croajingolensis (VU).

Young plants of Banksia saxicola and others at FossilPlants' research nursery.

Young plants of Banksia saxicola and others at FossilPlants’ research nursery.

Whilst some of Australia’s protea are found in rain-forest their main diversity is found in the dryer global biodiversity hot spot of the South Western Australian Floristic Region. The dry shrubland known as Kwongan occupies about a quarter of the region, and contains 70% of the hot spots 8000+ native plant species.

With over 80% of the world’s protea species now having a global red list status a clearer picture can be seen as to the range of threats to, and the conservation actions required for, this iconic and fascinating family of plants. As the honorary figure heads of the worlds massively bio-diverse and increasingly threatened shrub-lands such as Fynbos and Kwongan the plight of the proteas cannot now be overlooked. We at FossilPlants are pleased to be playing our small part in their conservation through our research into their cultivation through our Proteas with Altitude project.(http://www.fossilplants.co.uk/proteas-altitude/).

Read more from the IUCN on their latest red list update at https://www.iucn.org/news/species/202012/european-bison-recovering-31-species-declared-extinct-iucn-red-list