School of Psychology

Urban Biodiversity: A Social Psychological Investigation into Landscape Preference within the Suburban Backyard.

Research team:      Sophie Rothwell, Michelle Sermon, and David Edwards.

Supervisor:              Dr Tim Kurz

Date:                       7th October, 2008.
___________________________________________________________________________

With the increasing tendency towards urban expansion in Australia (and elsewhere), many areas of land that previously provided essential habitat for huge numbers of native animals (e.g., birds, mammals, reptiles, frogs) have been replaced by urban developments made up of small privately-owned landholdings (i.e., ‘suburbs’ comprised of ‘yards’). Whilst small patches of remnant bushland are often retained in the suburbs, the inability for animals to move between such patches creates massive ecological problems (at a population level) that inevitably lead to species extinction. As such, the development of biodiversity corridors (or ‘fauna highways’) between areas of remnant bushland in urban areas can be seen as an essential step towards the prevention of further species extinction and the maintenance of a highly biodiverse urban landscape. So how does this relate to psychology? Given that the areas in which such ‘linkages’ are required do run predominantly through private land (i.e., everyday peoples’ front and back yards), the necessary changes at an ecological level can only be achieved through the behavioural involvement of local residents in terms of their gardening practices (i.e., ‘gardening for habitat protection’). Thus, one can see how the problem of species loss is simultaneously both an ecological and a socio-cultural issue.
It has been suggested that the level of adequate habitat provision for local wildlife could be increased significantly by the establishment of biodiversity corridors in urban areas. The Perth Biodiversity Project (WALGA, 2007) detailed such a plan for certain areas in the Perth Metropolitan area, outlining a whole series of potential corridors that could  connect existing green spaces together and boost the areas overall level of biodiversity.
It is, therefore, extremely relevant to investigate exactly how local residents perceive different kinds of gardens and whether such preferences might have an impact on their willingness to incorporate habitat-providing elements (e.g., native plants) into their own gardens. The current project also aimed to investigate some of the attitudinal factors that might influence residents’ preferences for different kinds of gardens.

What we did:
2000 questionnaires were hand-delivered to the post boxes of a selection of households within the City of Melville and the City of Fremantle. These areas were selected for the study due to them being identified as a part of the proposed ecological corridors in the Perth Biodiversity Project (WALGA, 2007). The Melville ‘corridor’ ran from the Murdoch Campus north to Piney Lakes Reserve whilst the Fremantle ‘corridor’ ran northwards from Lefroy road to the Fremantle Golf Course and then westwards to Stevens Reserve and Monument Hill. In total, 488 residents (24.5%) responded to the questionnaire; 245 from the City of Melville and 243 from the City of Fremantle.

Overview of the Study:
The questionnaire consisted of 24 colour photographs of different front gardens, which participants were asked to rate on a 10-point scale in relation to how much they liked the garden depicted (1 = Dislike very much, 10 = Like very much), and to what degree they would want it in their own garden (1 = Would not want it at all, 10 = Would want it very much). Each photograph represented either a ‘high’ or ‘low’ habitat garden (as rated by an independent group of expert ecologists).
 The questionnaire also consisted on 39 questions that assessed four main topics; Attitudes towards Urban Biodiversity, Attitudes towards Native Plants, General Environmental Concern, and Sense of Community.
Demographic questions were also included encompassing the participants age, gender, income, ethnicity, type of household ownership, and current gardening practices.

What we found:
The sample of respondents, on average, showed a slight preference for high habitat gardens over low habitat gardens (5.1 out of 10 vs 4.1 out of 10). However there was a great amount of variation in residents’ preferences, some of which was found to be accounted for by the other variables that were measured in our questionnaire. For example:

• Participants that had positive attitudes towards native plants and high levels of general environmental concern were found to tend to prefer high habitat gardens,  whereas those who expressed less positive attitudes towards native plants and lower levels of general environmental concern tended to prefer low habitat gardens.
• A significant difference in preference was found between the Melville and Fremantle samples. The Fremantle residents, on average, preferred high habitat gardens over low habitat gardens whilst Melville residents preferred low habitat gardens over high  habitat gardens. Observation of the two sample areas suggested that this matched with what appeared to be norms relating to gardening practices in each of the two areas.
• Participants’ current (self-reported) gardening practices were significantly linked with their aesthetic preferences. Those that planted only native plants, or that planted both native and exotic plants preferred high habitat gardens, whereas those that planted only exotic plants, or were unsure as to whether the plants that they added to their garden were native or exotic preferred low habitat gardens.
• An interaction effect was found between residents’ aesthetic preferences for the two types of gardens, their attitudes towards native plants, and their levels of concern for the environment in general. The nature of this interaction suggests that for people high in general environmental concern, being pro native plants lead to a strong preference for high habitat landscapes, whilst being anti native plants lead to no clear preference for high as opposed to low habitat landscapes.  For people lower in general environmental concern, being pro native plants still lead to a preference for high habitat over low habitat gardens, but being anti native plants actually lead to this group showing significant preference for low habitat gardens in comparison to high habitat gardens.

Concluding Remarks:
This study allowed us to gain a further understanding as to the preferences and attitudes held by residents in two specific areas of Perth in regards to the issue of urban biodiversity.  Our results highlighted the degree of variability in residents’ aesthetic preferences in relation to different garden types. Whilst some residents did show preference for more ‘traditional’ garden aesthetics that involve less habitat-provision, a large proportion of residents also indicated a preference for gardens that incorporated habitat-providing elements. Such preferences appear to be most strongly driven by such factors as people’s attitudes towards native plants and the normative gardening practices of the suburb in which they live. The results of this exploratory study provide useful information that we hope to apply to the development of community-based programs for improving levels of habitat provision across Perth.