| BUGS Home | News | Background | Project | People | Helping | Contact |

umbellifer BUGS logo back gardens

The BUGS Project

Aims and objectives

The BUGS project aims to improve understanding of the role of domestic gardens in enhancing urban biodiversity, using the city of Sheffield as a case study. There are two main objectives:

malaise trapTo survey the biodiversity in a sample of representative domestic gardens from the residential areas of Sheffield.

The sample encompasses gardens along the urban-rural gradient, belonging to houses of a range of ages and types. We are recording the diversity and abundance of various invertebrate groups (e.g. beetles, parasitic wasps, molluscs, spiders) collected by several sampling techniques, as well as birds, mammals, macrofungi and plants. Plants are being categorized according to whether they are native or introduced, and whether grown intentionally or not. These measures of biodiversity will be related to garden characteristics e.g. size, aspect, vegetation structure, types of garden use, and methods of gardening. Equally important will be the nature of the surrounding habitats, such as the proximity of other gardens, semi-natural habitats, waste ground or buildings.

solitary bee nestTo test the efficacy of some popular methods for enhancing garden biodiversity.

Four experiments are being used: a) patches of food-plants (nettles) have been introduced to gardens to test for their ability to attract and provide breeding sites for widespread butterfly species; b) artificial nesting sites have been set up to investigate whether they attract bumblebees and solitary bees and wasps (see photo); c) small ponds have been added to gardens without ponds to determine how quickly they are colonized by aquatic flora and fauna, and what role they have for non-aquatic species; and d) small piles of logs have been placed in gardens to examine the colonization of such habitats by both invertebrates and fungi.


The main survey is being done over fifty gardens across the city of Sheffield, and involves detailed mapping of the features of each garden, based on ground surveys in individual gardens, and also features of the surrounding environment, using GIS-based urban map data, and aerial photographs. Invertebrates are being sampled using Malaise trapping, pitfall trapping, water traps, sampling on vegetation and litter sampling. In addition, garden owners are participating in additional recording of insect activity, birds and fungi. Detailed identification of specimens are being made for a range of invertebrate groups, plants and fungi, with the aid of a number of specialists in these groups.

Experimental manipulations are being monitored closely to quantify changes in abundance or occurrence of species associated with each manipulation. The focus of interest is on evidence for enhancements of breeding populations - which are likely to represent real increases in numbers, rather than just movement from nearby areas. However, evidence of new use of gardens by species, even if they are not breeding there, still provides evidence of an overall enhancement of habitat value.


The results from both parts of the work will considerably enhance understanding of the types of organisms which inhabit urban gardens, from those which are large and noticeable, to the smaller and more obscure, which may nonetheless be an important part of garden ecosystems, or may depend upon them for their survival. Such understanding will allow a much better assessment of the role of gardens in urban conservation, and the types of garden management and design that provide the best habitats. Synthesis of the information from both these sets of investigations will provide practical recommendations as to how gardens may best be managed to the benefit of biodiversity. This information will be of use to garden owners, in urban conservation initiatives, and in urban environmental planning.

In due course, the project outputs will be both in the form of formal reports in the peer-reviewed scientific literature, and explanatory summaries of the main findings for wider dissemination. Outputs will be catalogued on the News and updates pages of this site, and some will be available directly from there.

| Top of page | Contact us | About these pages |

March 2007