Poor ecological quality of urban ponds in northern England: causes and consequences [dataset]

The value of ponds in urban areas historically has been overlooked. While some recent studies have described considerable biodiversity in urban areas, it is unclear as to how far this extends to different urban habitats. The aims of this study were to determine the condition of 21 urban ponds in Bradford (northern England) and to quantify the connectivity of wetlands in the district. The study showed that macroinvertebrate and plant biodiversity was substantially lower than would be expected based on pristine reference sites. Of the 21 ponds surveyed, 15 were found to be classified as having very poor ecological quality, with 5 being classed as poor and just 1 was classed as moderate. The number of aquatic plant species found in the ponds ranged from 0 to 6 and the number of macroinvertebrate families found ranged from 4 to 13. It was suspected that the aquatic plant diversity was low due to management techniques such as the removal of emergent vegetation. The average distance to a wetland was found to be higher in urban areas (533 m) compared to rural areas (448 m) although this difference was small, which indicates that the low diversity found in urban ponds is likely due to habitat variables.