Wildlife and Plants

Wildlife and plants in Bristol’s Floating Harbour

cormorantBristol’s Floating Harbour is alive with a variety of animals and plants. Most can be seen by just going for a walk along the Harbour – look out for cormorants, ducks, gulls and colourful flowers during the summer.

Water Quality

Although the water may look brown and dirty, it is full of life and very clean. The brown colour is caused by mud mixed in with the water. However, the harbour hasn’t always been so clean. 150 years ago the Floating Harbour would have been very smelly and dirty. This was because most of Bristol’s sewage flowed into the water, polluting it. This was stopped in the early 1970s. Nowadays, the water is tested every week to make sure it is safe and clean for people and wildlife. Many different types of fish are found in the harbour. Fishermen commonly catch bream, roach and even eels!

Wildlife and Plants

The habitat available for wildlife has changed hugely over the past 200 years. Back then much of the area was meadowland and marsh, full of butterflies such as the marsh fritillary. These gradually disappeared, replaced by factories, railways and storage buildings. This urban environment became home to new plants and wildlife. When horses were still used around the city, large flocks of house sparrows, now a rare bird in Bristol, would have been commonly seen. They were attracted by horse feed, insects and places to nest in nearby sheds.

balsamMany of the flowers found around the Floating Harbour are not from Bristol or even the UK. Several originally come from warmer climes such as southern Europe and Asia. They have arrived here via domestic gardens, boats and sewage. Some, such as Himalayan balsam, are highly invasive and stop native plants from growing. During the winter they die off, leaving bare soil that is vulnerable to erosion and can cause riverbanks to be washed away. Organised work parties regularly meet to cut down invasive plants and allow native ones to grow.

Before the Floating Harbour and the New Cut were built, the water flowing through the area was tidal; the water daily rose up and down with the rising and falling tides. Once they were built, the water held in the Floating Harbour remained at the same level. This enabled boats to move in and out of the area without getting stuck in the mud for hours. While the constant water level meant plants and animals could no longer use the mud to live in, the New Cut provided a fresh habitat of tidal mud for them instead.

At Bristol’s City Museum & Art Gallery, there are many maps and paintings (Bristol School of Art) showing how the landscapes around the harbour and Avon Gorge have changed over time.

Interactive map

Did you know?