In my time here at Londolozi since the beginning of 2020, we’ve experienced several years of consistently high rainfall. The reliable rains have contributed to a flourishing environment, with healthy grazing lands and rivers that sustain both wildlife and the landscape. However, this year has been noticeably drier—a significant shift from the patterns we’ve come to expect.
This change got me thinking about the larger climate systems that influence weather in Southern Africa, particularly the El Niño and La Niña cycles. These global phenomena don’t just affect rainfall; they play a critical role in shaping everything from soil health to animal behaviour.
At Londolozi, these cycles remind us how interconnected the landscape truly is. From shifts in vegetation to the movements of wildlife, the effects of El Niño and La Niña ripple through every part of the ecosystem. Let’s take a closer look at what these cycles mean for Londolozi and how they influence the environment we call home.
What are El Niño and La Niña?
El Niño and La Niña are opposite phases of the El Niño-Southern Oscillation (ENSO), a climate pattern originating in the Pacific Ocean but influencing weather patterns globally.
- El Niño: Characterized by unusually warm Pacific Ocean temperatures, it often results in drier and hotter conditions in Southern Africa.
- La Niña: Defined by cooler Pacific Ocean temperatures, it typically brings wetter and cooler weather to the Londolozi region.
Both cycles influence precipitation, temperature, and vegetation patterns, making their impacts felt across Londolozi’s unique environment.
Current ENSO Cycle and Recent Trends
As of November 2024, the ENSO cycle is in a neutral phase, following a significant El Niño event that concluded earlier this year. The El Niño, which began in June 2023 and peaked in December 2023, was among the five strongest on record, contributing to elevated global temperatures and various extreme weather events.
The transition from El Niño to neutral conditions has been observed, with the possibility of a La Niña event developing later in the year. The Bureau of Meteorology has noted early signs of a potential La Niña formation, indicating a 50% chance of its development.
Ken Tinley’s Vision and the Londolozi Landscape
The late ecologist Ken Tinley profoundly shaped the understanding of the Londolozi landscape, particularly the relationship between soil, vegetation, and wildlife. Tinley emphasized that soil types are the foundation of ecosystem health, dictating where water flows, where grass thrives, and where animals graze.
At Londolozi, three dominant soil types interact with the cycles of El Niño and La Niña:
- Clay-rich basalt soils: Found in low-lying areas, these soils retain water, making them critical during droughts.
- Sandy granitic soils: Found in upland areas, these drain quickly and are prone to erosion during heavy rains.
- Alluvial soils: Along riverbeds, these are fertile and support rich vegetation, crucial for herbivores like elephants and nyala.
El Niño and La Niña cycles magnify the strengths and vulnerabilities of these soils, influencing how water is stored and released, which in turn affects the survival of plants and animals.
El Niño: Dry, Hot, and Challenging
During El Niño years, Londolozi experiences prolonged dry spells. The basalt soils, with their ability to retain moisture, become critical refuges for grazing herbivores like zebra and buffalo. However, sandy granitic soils, which dry out quickly, become barren, pushing animals to riverine areas supported by alluvial soils.
Drought conditions also lead to:
- Shortened grass growth cycles, forcing herbivores to move more frequently in search of food.
- Concentrated water sources, make predator-prey interactions more predictable. Lions and leopards, for instance, exploit these patterns, staking out waterholes to ambush thirsty prey.
- Reduced tree cover: Many trees, such as knobthorns, struggle in drought, which impacts bird species like vultures that rely on tall trees for nesting.
La Niña: Abundant Rains and Flourishing Life
In contrast, La Niña years bring heavy rainfall. Grasslands on sandy soils flourish, providing ample grazing for species like impala and wildebeest. The abundance of water spreads wildlife across the reserve, reducing competition at waterholes but also dispersing prey, making hunting harder for predators.
Rainfall brings its own challenges:
- Soil erosion: Intense rains on granitic soils can strip vegetation, exposing bare ground.
- Flooding: River systems like the Sand River swell, altering access routes for animals.
- Disease outbreaks: Wet conditions can spread diseases like anthrax or foot-and-mouth disease, particularly among herbivores.
Yet, this abundance fosters new life, with many species timing their breeding seasons to coincide with the rains. The calls of frogs fill the night air, while migratory birds return to feast on the explosion of insects.
Soil, Weather, and Animal Interactions
Tinley’s work helps us understand how these cycles influence animal behaviour:
- Elephants: During droughts, they rely on riverine forests, stripping bark and pushing over trees to access nutrients. In wet years, they roam widely, feeding on lush grass and shrubs.
- Predators: Lions and leopards adapt their hunting strategies to the changing prey distribution. Droughts create concentrated hunting grounds, while rains disperse prey, requiring predators to cover larger territories.
- Grazers and browsers: Species like kudu and nyala shift their feeding patterns based on vegetation availability, often retreating to the denser bush during droughts.
Looking Forward
Understanding the cycles of El Niño and La Niña gives us a deeper appreciation for the resilience of Londolozi’s landscape and its wildlife. It also underscores the importance of sustainable land management practices that honour the principles laid out by Ken Tinley. By conserving soils, protecting water sources, and maintaining a balance between natural systems, Londolozi can continue to thrive in the face of these powerful global forces.
The next time you stand on the crest of a granite koppie, watching the Sand River twist through the bushveld, consider the hidden forces shaping this paradise. From the dryness of El Niño to the abundance of La Niña, the story of Londolozi is one of adaptation, resilience, and harmony—a lesson from nature that we can all learn from.
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