The climate crisis could kill the Namaqualand daisy…

In a recent research paper titled Phenological advance in South African Namaqualand Daisy First and Peak Bloom: 1935–2018, Pascal Snyman and Jennifer Fitchett used documented phenological data spanning 83 years, as well as climatic data for the Namaqua region spanning 59 years, to determine the phenological effects of climate change on Namaqualand daisies.

Phenology, simply put, is the study of the timing of biological events, such as seasonal changes that determine when flowers bloom and when they go dormant. Snyman and Fitchett found that climate change altered the seasonal cycle of Namaqualand daisies.

Specifically, these wildflowers experience their first bloom 2.6 days earlier each decade and their full bloom 2.1 days earlier each decade. While this won’t set off alarm bells for everyday dwellers, who might consider it fortuitous that daisies are blooming earlier, the short- and long-term effects shouldn’t be underestimated.

Daily Maverick spoke to Fitchett, who highlighted two main reasons why this weather phenomenon could weaken daisies to the point of extinction.

The first is that the dormant phase of daisies, usually winter, is shortened by warmer weather. This dormant period is essential for “storing and accumulating energy for the next breeding season,” according to Fitchett.

“The earlier the flowering date, the shorter the dormant phase, and therefore the shorter the time period for plants to rest and recover,” she added.

The second reason is a “Catch-22”. Despite warmer winter climates due to climate change, the Western Cape and Northern Cape, where the Namaqualand daisy is endemic, experience “mid-latitude cyclones” that can trigger “freezing events” regardless of be the warmer temperatures.

“If a frost event occurs during the flowering phase, it is likely to weaken or destroy the flowers – shortening the flowering season – and preventing successful seeding, which then affects the daisies of the following year,” Fitchett said.

In theory, daisies could be harvested agriculturally by growing them in greenhouses, “but that takes away from the spectacle of Namaqualand daisies.”

Moreover, and more immediately, such a measure would negatively affect tourism. “So we could prevent the species from becoming extinct, but we wouldn’t save the tourist attraction,” Fitchett said.

In their 2007 article titled The Value of Floral Tourism at Namaqua National Park: Environmental and Ecological Economics, Ivor James, Michael Timm Hoffman, Alistair Munro, Patrick O’Farrell and Russel Smart have suggested that the wildflowers in the region attract around 10,000 tourists per season.

If there were seasonal changes and a decline in daisy populations, tourists would not be able to properly plan viewing trips.

It is impossible at this time to determine when these climatic effects will become irreversible, but Fitchett suggests that they are “tipping points”.

“A few years of failed flowering could cause irreversible damage if no seeding takes place, but it’s hard to predict when that would happen,” she explained.

What is certain is that biodiversity will suffer in wildflower areas. Since Namaqualand daisies do not grow elsewhere, other wildlife species in these areas will also feel the changes and decline.

“They provide habitat and food for insects and birds, and are therefore part of an ecosystem,” Fitchett said. “So any loss of species richness is a loss to biodiversity, but also a threat to the rest of the food chain.”

The point of irreversibility has not yet been reached.

Snyman and Fitchett suggest in their paper that South Africa needs increased phenological investigation and data-driven research to effectively tackle the problem.

Earlier, Fitchett and a team used a similar methodology to highlight the impact of global warming on the blooming jacaranda trees in Pretoria and Johannesburg.

Fitchett argued for “a strong focus on a just transition” in terms of energy resources. “We urgently need to move away from coal and towards renewable energy.” DM

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