Abstract:

Aims: With the acceleration of global urbanization, urban ecosystems are becoming increasingly important. Community habitat gardens, which are gardens that are populated with native plants and are designed to attract animals, positively impact urban biodiversity conservation in high-density cities. Thus, habitat gardens have drawn attention from academia and government institutions, but there is a lack of research on the exact impact of these gardens. Specifically, there is a need for quantitative research on species composition, interaction, and external factors in habitat gardens. This study aims to catalog the species composition, relative population size, and spatiotemporal distribution of wildlife in habitat gardens. These data can then be used to identify species’ responses to biotic and abiotic factors within the city, and to identify and assess specific threats to the animals in these urban communities. This analysis will inform effective wildlife conservation measures and adaptive management recommendations.

Methods: We surveyed 10 sites in seven habitat gardens in the Changning District of Shanghai from February 11, 2023 to January 13, 2024 using camera trapping technology. From this, we collected 20,375 photos of birds and mammals within 627 effective camera days. Based on this camera trapping data, methods including the relative abundance index, kernel density estimation, avoidance-attraction index, biodiversity index, and regression analysis were used. We explored the species composition of habitat gardens, assessed the relative sizes of animal populations at the community scale, analyzed the diel activity of different species, and investigated avoidance-attraction relationships between the species, revealing complex relationships between the animals and the habitat gardens.

Results: The results indicated that at least 15 species of birds and five species of mammals existed in the habitat gardens in the Changning District. Out of all the species that were detected, the relative abundance index of cats (Felis catus) was the highest. Diel activity analysis showed temporal avoidance relationships between cats and other wildlife, with the cats posing a particular threat to birds and small mammals. The patch area of the blue-green infrastructure in the landscape surrounding the habitat gardens, quantified using a 1-meter resolution land use map, showed a positive correlation with species richness index (S) (r= 0.09, P > 0.05), diversity index (H) (r= 0.03, P > 0.05), and evenness index (EH) (r= 0.01, P > 0.05) within the gardens, although not significantly. The relationship between habitat garden area and species α diversity was weak and insignificant (P > 0.05). Finally, species inhabited different spaces within the habitat gardens (β diversity).

Conclusion: This study provides quantitative evidence that community habitat gardens can form ecological networks in synergy with other urban green spaces, thus providing stepping stones for urban wildlife. This study also highlights that proliferation of cats has a destructive impact on the biodiversity within habitat gardens. In future urban planning, habitat gardens should be incorporated into urban biodiversity conservation plans. Specific attention should be paid to their synergistic conservation effect with the surrounding landscape and on how to strengthen the eco-friendly design of habitat gardens. For example, the gardens should incorporate design elements that provide food, water, and shelter for animals to improve their survival. Additionally, It is essential to implement more strict management of domestic and feral cats within the community and bolster community involvement in maintenance of the garden space.

Key words: habitat garden, community scale, urban biodiversity conservation, camera trapping, Changning District Shanghai