Start with the smallest to make the biggest gains for freshwater biodiversity
22nd September 2025
Focusing on the smallest habitats can make the biggest difference for freshwater biodiversity, explains Freshwater Habitats Trust Technical Director and Newt Conservation Partnership CEO Dr Pascale Nicolet.
Our vision to build the Freshwater Network encompasses the whole freshwater environment, but with a particular focus on small habitats.
‘Start with the smallest’ is one of the four principles of the Freshwater Network. But what does that really mean? It’s easy to assume that the bigger and deeper a waterbody is, the more important it must be for nature. If you look at most maps, you’ll spot big rivers and lakes, but many ponds and small fens are missing. Environmental policies are mainly focused on large waterbodies.
It’s a natural bias, known as the ‘saliency error’, where what stands out visually grabs our attention, regardless of its actual importance.
But for freshwater biodiversity, the opposite is often true.
Small habitats, big value
To reverse the decline in freshwater biodiversity we need to focus on the whole freshwater environment – big and small.
When we talk about small waters we’re referring to small waterbodies like ponds, headwater streams, flushes, ditches, and habitats like small fens. Although they are individually small, these habitats make up an estimated 80% of the freshwater environment.
Not only are small waters the biggest part of the freshwater environment, they are also the richest in biodiversity at the landscape scale, providing critical stepping stones for plants and animals, and often acting as strongholds for populations of rare and threatened species.
- Newt Conservation Partnership CEO Dr Pascale Nicolet carrying out a plant survey at a site in Sussex.
Our own research has shown that, collectively, ponds support more species of macroinvertebrates and plants than lakes or rivers. Greater numbers of rare and uncommon species are found in ponds compared with larger waterbodies. Yet, because of their size and perceived insignificance, small waters have traditionally been left out of policy frameworks and large-scale conservation efforts. This is changing, but we still have a long way to go before small waters are given the attention they deserve.
Starting with the smallest makes good business sense too. Small waters are easier to create and restore than large waterbodies, presenting an opportunity for us to rapidly boost freshwater biodiversity, and make freshwater ecosystems more resilient to growing threats such as climate change.
The science on small waters
Research from the last two decades has repeatedly shown the critical importance of small waters for freshwater biodiversity. At Freshwater Habitats Trust, we’ve played a key role in these discoveries – conducting pioneering work to build this evidence base.
Studies have shown that:
- High-quality ponds can support up to two-thirds of all freshwater plant and animal species in a landscape.
- Rare and declining species are disproportionately found in small waterbodies.
- Ponds that are not connected to sources of pollution can bring clean water – an increasingly scarce resource – back to the landscape.
- In fragmented landscapes, small freshwater habitats act as refuges and stepping stones for species on the move.
This research is slowly changing how people think about conservation in freshwater environments. It’s no longer enough to focus only on rivers and lakes. To halt – and reverse – biodiversity loss, we have to start with the smallest.
- One of eight clean water ponds at one of the NCP compensation sites around Yardley Chase SSSI. The site already supports a new breeding population of Great Crested Newt and also red pondweed, a Vulnerable plant species in England.
Protecting, creating and restoring small waters
We’ve been putting this principle into action for decades through our practical conservation work. This has included protecting existing small waters, restoring those that have been lost or degraded, and creating new high-quality habitats in locations where they can make the most difference for freshwater wildlife.
In places like the New Forest, the River Irfon catchment in mid-Wales and across Oxfordshire and Buckinghamshire, we’re working with partners and landowners to identify the highest quality small habitats and ensure they are protected for the long term. We’re also identifying opportunities to create new habitats that meet the highest standards of clean water needed by the most pollution-sensitive plants and animals.
Our work with the Newt Conservation Partnership (NCP) demonstrates how well–designed and strategically located ponds can quickly restore wildlife to a site or landscape. For every pond occupied by Great Crested Newt that is lost to development, NCP creates four new ones. Eighty-four percent of our older compensation sites are now colonised by Great Crested Newt and this is set to increase as the ponds become more established. The scheme also provides wider benefits for priority species, and nationally and regionally rare plants recorded at many sites.
Meanwhile, in the pioneering new Headstart project, we’re working with the water industry to kickstart nature recovery by harnessing the power of small headwater catchments.
Speaking up for small waters
Along with practical action on the ground, we’re fighting for small waters to be recognised and protected in policy. Because they are relatively cheap, quick and easy to create, restore and manage, small waters represent a golden opportunity in our collective efforts to tackle biodiversity loss.
We recently joined forces with a coalition of environmental charities, including The Wildlife Trusts and National Trust, to launch the Charter for Small Waters. This paper calls on Government to recognise the potential of small waters and unlock their potential for nature restoration.
Meanwhile, our recent white paper, Incorporating small freshwater habitats into your Local Nature Recovery Strategy, is helping local government harness the power of small waters for nature restoration.
The Independent Water Commission’s Final Report, published in July, outlines 88 recommendations for reforming environmental regulation. During our engagement with the Commission, we emphasised the importance of including small waters in statutory monitoring and management of the water environment. And we were encouraged to see some acknowledgement for small freshwater habitats in the final report.
- A pond at Busketts Wood in the New Forest.
We still have a long way to go in improving policy for small waters. For example, the vast majority of small waters are excluded from the UK’s most significant piece of legislation for freshwater: the Water Framework Directive. This is a piece of EU legislation, but was transposed into domestic law by the Water Environment Regulations in 2017. Monitoring under the Water Framework Directive currently excludes almost all standing waters less than 50 hectares, as well as many small streams. This means that pressures on small waters are not identified, and actions to address them are not prioritised. Reforming the Water Framework Directive is one of many policy levers which could unlock the potential of small waters to drive nature recovery.
Small waters, big thinking
We have come a long way in the last three decades, building a strong evidence base to demonstrate the importance of small freshwaters through our research and practical conservation work. Our partners are embracing this approach and are working with us to protect existing high-quality habitats and create new clean water ponds and small wetlands. But there is still work to be done to create a mindset shift around the role of small waters in nature restoration.
To build the Freshwater Network, we need to think even bigger – and that means starting with the smallest.