Last modified: 5 February 2023

About our Thames conservation work

Did you know there are seals in the River Thames?

The Thames ebbs and flows through the heart of London and is not only a busy urban waterway, but is also home to a fascinating and often unexpected array of wildlife, from seals to eels. Declared ‘biologically dead’ in the 1950s, subsequent changes in effluent sewage treatment have substantially improved water quality and, as a result, biodiversity.

Since 2004, ZSL has been working tirelessly with partners and volunteers to drastically improve the ecology and biodiversity of the Thames estuary and the wider river catchment, and to protect and better understand the species that are found here, including invasive non-native species

Get involved

You can get actively involved in our conservation work, whether it be reporting your sightings of marine mammals like seals and dolphins, or volunteering as a citizen scientist and joining our survey work throughout the Thames river basin. 

You can also help us to protect marine biodiversity by using a refillable bottle to reduce plastic pollution - take the #OneLess pledge today!

Volunteer with us

Get actively involved in our Thames conservation work and help us to protect wildlife on our doorstep. 

Reduce plastic pollution and help us restore ecosystems
Take the #OneLess pledge today!

Find out more about our Thames conservation projects

  • A group of citizen scientist volunteers in a river
    Join us in our vital conservation work

    Volunteer for London's Rivers

    The River Thames and its tributaries are home to a diverse array of wildlife, and ZSL is working to conserve and enhance this ecosystem. Join us today.

  • Volunteers digging for invasive shellfish on the banks of the River Thames
    We're monitoring invasive non-native species in the Thames

    Thames Invasive Species

    We've conducted the most comprehensive studies of juvenile fish in any estuary in the UK, and tagged the first fish to swim through central London.

  • Spurdog shark in the Thames
    Did you know there are sharks in the Thames estuary?

    The Greater Thames Shark Project

    Working together with anglers to better understand the importance of the Thames estuary to these animals and to ensure their long-term survival in the wild.  

  • Four ZSL conservationists study fish and record results on the Putney foreshore
    ZSL is working to conserve fish in the tidal Thames

    Fish conservation in the tidal Thames

    At ZSL, we have been studying fish in the tidal Thames since 2015

  • a group of seals seen during our aerial surveys in the Greater Thames estuary.
    Protecting harbour and grey seal populations in the Thames

    Thames Marine Mammal Conservation

    ZSL has been monitoring marine mammals in the Tidal Thames since the early 2000s, to better understand and conserve species such as grey seals, harbour seals and porpoises.

  • conservationists_wading_through_river
    A vital habitat for wildlife

    London’s Rivers

    Please help us health-check and survey our rivers as part of our ongoing programme of Citizen Science projects.

  • european eel closeup of face
    The species are now classified as ‘Critically Endangered’

    European eel conservation

    European eels once thrived in London’s rivers but the number of young joining the adult populations has dropped dramatically since the 1980s.

  • marine habitat
    Putting the health of our marine ecosystem first

    Marine Habitat Restoration

    Marine habitats are essential to the health of our marine ecosystem, and hold environmental and social importance, providing valuable ecosystem services.