5. An Ecological Transition in Progress Now
| Theme: | ECOLOGY NETWORKS |
|---|---|
| Current Topic: | Riverside Park |
| Thread Title: | An Ecological Transition in Progress Now |
| Thread Number: | 5 of 7 |
| Learning Focus: | A look at the species counts within Sidmouth's Riverside Park. Explore why trees thrive but grass and mammal diversity face challenges from human activity. |
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5 Surprising Truths About the Biodiversity of Riverside Park
To the casual walker, the Riverside Park ecological network appears as an idyllic, lush corridor of nature. It is easy to assume that because a landscape is green, it must be teeming with a vast variety of life. Looking past the visual "greenery" and into the data we can compare this specific network to the total survey area surrounding it, we find a landscape that is complex, often misunderstood, and deeply marked by its human history. While the park is undeniably vibrant, its biodiversity is a unique reflection of past management, creating an ecological profile that is far more nuanced than it first appears.
The Dominance of the Canopy: Why Trees Lead the Way
One of the most striking features of the park’s data is the overwhelming success of its woody plants. While other biological groups show mixed results, trees and shrubs are the undisputed leaders here, with 33 out of 45 possible species present—a robust 73.3% representation. This success is closely mirrored by Pteridophytes (ferns and their relatives), which boast a strong 60% presence.
This success is not accidental. The park’s current botanical strength is a direct result of how the land was managed long before it became a protected ecological network. Conversely, mosses (Bryophytes) are significantly under-represented at just 25.8%, illustrating that this is a landscape designed for height and structure rather than the low-lying carpet of an ancient woodland.
"Undoubtedly, the parkland heritage of the area is the major reason for this [diversity of trees and shrubs]."
The Ghost of Grazing Past: The Grassland Paradox
Given the sprawling open spaces within the park, one might expect a high variety of grasses. However, the data reveals a "grassland paradox." Only 23 out of 45 local species of grasses, rushes, and sedges are present—just 51.1%.
The reason for this lower-than-expected diversity lies in the soil’s history. For decades, much of these open grasslands were used for livestock grazing. This historical human land use permanently altered the composition of the meadows, creating a lasting impact that dictates exactly what can—and cannot—grow under our feet today. This human-centric legacy doesn't just dictate which plants take root; it fundamentally shapes the environment for every mobile creature that attempts to call this network home.
The "Invisible" Inhabitants: Why We Miss the Wildlife
When it comes to animals, the recorded numbers seem surprisingly low: only 3 mammal species and 23 bird species were observed. But this doesn't necessarily mean the park is empty. Instead, it highlights a conflict between human recreation and animal behaviour.
Wild mammals are naturally "nervous" of human activity and many are nocturnal, meaning they are tucked away while visitors are out for a stroll. Furthermore, heavy human impact—specifically dog disturbance along the river in areas like The Byes—directly limits the presence of specialised waterside species. In many ways, the recorded data understates the reality of the park's wildlife; nature is actively hiding from its human neighbours.
The Running Water Trade-Off: Where are the Dragonflies?
It is a common misconception that the presence of a river automatically guarantees a high diversity of dragonflies and damselflies (Odonata). Despite a river running the entire length of this network, only 4 species were recorded out of 9 in the wider survey area.
The irony of this river-side park is that the water itself is the challenge. Most Odonata species require standing water for breeding and larval development. The fast-moving waters of the river are actually "unfavourable" habitats for these insects compared to the still ponds or marshes they prefer. Consequently, the very feature that defines the park—the flowing river—is exactly what limits the variety of these iconic insects.
The Illusion of Abundance: Volume vs. Variety
Walking through the park in the summer, you might see fields overflowing with wildflowers. However, there is a distinct difference between volume and variety. Sites like Sid Meadow and Margaret’s Meadow provide a perfect example of the "High Volume/Low Variety" trend.
While Sid Meadow may be white with a "huge amount" of Wild Carrot and Margaret’s Meadow yellow with Meadow Buttercup, these "seas of colour" often represent a few dominant species. Yet, there is a fascinating ecological trade-off here: while floral variety is low, these high volumes of specific plants support a thriving population of Hymenoptera (bees, wasps, and ants). This group is the only insect order to exceed 50% representation in the network, proving that even a "low variety" field can be a powerhouse for specific pollinators.
"there is a tendency for high volume/low variety as one can see in the Sid Meadow with the huge amount of wild carrot."
Conclusion: A Future in Flux
The ecological value of the Riverside Park network is immense and "cannot be over-stated." It serves as a vital green lung for the region, yet it is clearly a landscape in transition. As the influences of past land-use practices—like livestock grazing and formal parkland management—continue to fade, the potential for the park to evolve into a more naturally diverse ecosystem is enormous.
Can we learn to value a landscape that isn't just green, but truly wild?
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