E m e r a l d N e c k l a c e. M a t t S e a r l e

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1 E m e r a l d N e c k l a c e M a t t S e a r l e

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3 C o n t e n t s : 1.0 Research Question p Rationale p Aims p Methodological Overview p Bird Profiles p Regional Analysis p Reflection p Corridor Analysis p Reflection p Zoning p Zone classification p Zoning Scheme p Zone Chart p Emerald Necklace p Proposed Habitat Corridor p Predicted Function of Habitat Corridor p Site Design p Analysis Data Interpretation p Concept Development p Design Outcomes p Conclusion and Reflections p References p. 62 n e c k l a c e 3

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5 1.0 R e s e a r c h Q u e s t i o n : How can the development of a functional habitat corridor for Kereru and the White Faced Heron drive the design of urban landscape? 1.1 D e f i n i t i o n s : Patch - A node of vegetation that has edge and core contditions, generally able to sustain itself through succession and populations of native fauna. Corridor - Either a narrow stretch of vegetation that links patches within the matrix; or a ecological pathway that consists of vegetative stepping-stones. Matrix - Most extensive/connected or dominant landscape element, all other landscape elements can be located within it (i.e. housing in a sub-urban area or pasture in a rural area). Stepping-stone - a node of vegetation that is used by fauna to more from one habitat to the next. Habitat - The physical and biological environment on which a given species depends for its survival. Habit - A recurring pattern of behavior resulting from habitat requirements. Pattern - Repeated sequences of natural occurrences (i.e. urban sprawl/residential areas, vegetation patches, open space patches, all contribute to landscape, the arrangement or sequence of these is pattern). Process - A naturally occurring or designed sequence of changes of properties or attributes of an object or system. Works within or to create landscape pattern (i.e. succession is the process that a forest uses to regenerate itself, creating/changing landscape pattern as a result). Landscape - A mosaic of different land cover and land use patches within a geographic region or matrix. Ecology - The relationship of living things to one another and their environment. Ecological Integrity - The ecological condition of the landscape (i.e. forest composition, structure, and function). Fragmentation - Division or disintegration of a whole. In a landscape sense, this is the division or disintegration of a dominant land cover (i.e. Auckland s forest/vegetation structure is very fragmented). Aesthetics - Relates to the artistic or beautiful; or what people deem as culturally appropriate/tasteful visual elements. n e c k l a c e 5

6 2.0 R a t i o n a l e : New Zealand is viewed by many as an advocate for the environment (Ministry for the Environment, 2008), concerned with the sustainable management of its natural and physical resources as outlined in the Resource Management Act (1991). However, in many cities around the country these natural and physical resources are either damaged, destroyed or under significant threat from ever expanding urban sprawl. In Auckland City, the past 100 years of urban development has left the cityscape empty of all but small patches of the native vegetation that is essential for the sustainability of many species of native fauna. Many of these patches of bush and forest provide sufficient habitat conditions for wildlife, but lack the connectivity needed for adequate biodiversity. Native bird populations are a good indicator of the impact urban sprawl has on the New Zealand landscape. Kereru or New Zealand Pigeon is considered a keystone species, which means that if a viable population of the bird is present then the forest or bush ecosystem is in good health. The Kereru is not present in many forest patches and ecosystems throughout the country; they either cannot be sustained in those environments or cannot reach them due to urban sprawl. The Auckland region has had an increase in occupied dwellings of 11.2% between 2001 and 2006 in order to deal with the 12.4% population increase over the same period (ARC, 2007). This huge residential growth rate is putting massive pressure on the Auckland City landscape. Integration of social and ecological environments is vital for the long-term sustainability of our city in the future. Robert Thayer says that Landscape is where the current conflict between technology and nature is most easily sensed; it is also the place where any attempt at resolution of the conflict must be tested and proven. The conflict between technology and nature in Auckland s urban environment could be resolved with careful planning and design that addresses both social and ecological pattern and process with equal consideration. This could be done through a mapping and analysis process that aims to gain an understanding of how a site or region works ecologically as mapping is perhaps the most formative and creative act of any design process (Corner, 1999). This data could be used to design in a way that incorporates human pattern and process to form hybrid urban spaces where ecology and society work in harmony. In Auckland city the largest areas of open space available for the strengthening of its urban ecology network are its parks, reserves, community spaces and privately owned open space such as golf courses. Modification of these spaces so they are capable of supporting keystone species like Kereru could create ecological corridors which would be a step toward the de-fragmentation of the cityscape. Another way of integrating society and nature at a regional scale would be the study and use of a natural element that is currently common within the urban context and attempting to integrate it further. Previous research into Heron Park, a recreational reserve in Auckland City, has kindled my interest in the bird it is named for, the White-Faced Heron. This bird is a marginal species and a wader, although it has the ability to fly, it only does so over short distances of up to 1km (Meurk & Hall, 2006). The Heron also prefers open grass space for feeding and tall exotic trees for breeding, both elements common in parks around the city. An approach to urban landscape design in Auckland city that is based on the connection of open space using principles derived from the pattern and process of native bird species seems like an optimal way of incorporating ecology into the urban matrix. One aspect of urban landscape design that has received little attention is the incorporation of native animal habitat into green areas in cities. Creative habitat design offers opportunities both for new techniques of landscape research and design, and for the development of new types of urban places. (R. Barnett) 6 e m e r a l d

7 3.0 A i m s : To gain an understanding of the habits and habitats of the White Faced Heron and Kereru. Develop an ecological habitat corridor for the White Faced Heron and Kereru that traverses the Auckland isthmus from Titirangi to Meola Reef. Make amendments to the Auckland City district plans open space rule and regulations to accommodate the implementation of this corridor. To show how this ecological entity could work at a site scale using birdlife analysis data and integrating this with human processes; which drives the production of a design that provides unique, exciting open space that meets all current and proposed zoning requirements. The site chosen for this part of the project consists of three separate open spaces along Great North Road as it runs through Waterview, Auckland City. These spaces are Heron Park, Oakley Creek Esplanade and the Great North Road motorway interchange. The design should integrate people and wildlife, allowing them to interact and activate these open spaces in a way that promotes the ecological and infrastructural connection of Titirangi and Meola Reef. It is hoped outcomes of this design would include: Introduction of the New Zealand Pigeon or Kereru to the Waterview area. Increased biodiversity of the Avondale/Waterview/Point Chevalier area. This could include many plant and animal species such as insects, invertebrates and native bird species. Additional recreational space and facilities at Heron Park, Oakley Creek Esplanade and the Great North Road motorway interchange. Concept Design Area Increased ecological services such as water treatment processes, carbon consumption and soil generation. Education or public awareness of the underlying ecological complexity of the isthmus and how fragile and fragmented it is. Enhanced streetscape along Great North Road to improve pedestrian and vehicular experience. Corridor Study Area.

8 4.0 M e t h o d o l o g i c a l O v e r v i e w : R e s e a r c h Q u e s t i o n : How can the development of a functional habitat corridor for Kereru and the White-Faced Heron drive the design of urban landscape? A i m s & R a t i o n a l e : The development of an ecological corridor and supporting urban space design through research and analysis of the habit/habitat of the White-Faced Heron and Kereru. B i r d P r o f i l e s : A literature review and summary of information on the White-Faced Heron and the New Zealand Pigeon or Kereru. R e g i o n a l A n a l y s i s : GIS mapping of the ecology of the Auckland Region. C o r r i d o r A n a l y s i s : Design analysis of the habit/habitat of the White-Faced Heron and the Kereru in the urban matrix. Selection of open space stepping-stones. Z o n i n g : Classification of selected open space and additional zoning criteria in order to facilitate the creation of a functional habitat corridor. E m e r a l d N e c k l a c e : A functional habitat corridor that spans the isthmus from Titirangi to Meola Reef. S i t e D e s i g n : A design driven by the habitat of the Heron and Kereru that provides unique, exciting open space that meets all current and additional zoning requirements. O u t c o m e s : New urban spaces, enhanced urban ecology, increased biodiversity, expanded knowledge of corridors in citys. 8 e m e r a l d

9 5.0 B i r d P r o f i l e s : White-faced Heron Ardea novaeseelandiae novaeseelandiae Distribution: Throughout coastal New Zealand. Habitat: Self-introduced from Australia in the late 1940 s, this species is now common on sheltered sea coasts, estuaries, harbours, inland lakes and open farmland. The heron will fly or hop between viable habitat areas for feeding or breeding, the birds have an immediate flight range of approximately 1km. although may travel large distances over longer periods of time as demonstrated by their migration from Australia. Characteristics: Prominent white face and dark trailing edge to wings in flight. Often occur in large flocks during winter, especially on mudflats. Food: Wide range of small fish, crustaceans, frogs, tadpoles, earthworms and insects. Has habit of raking with feet to disturb invertebrates in tidal pools, wetlands and pasture. Breeding: (June September) Nests earlier in the northern districts. Favourite nest sites are in pine, macrocarpa, and large pohutukawa trees. Nest of sticks, often flimsy, supported on leafy branches, contains 2 4 turquoise coloured eggs. Both sexes incubate for days. Chicks fledge when 6 weeks old. New Zealand Pigeon (kereru) Hemiphaga novaeseelandiae novaeseelandiae (keystone species) Distribution: Throughout forested patches in New Zealand. Moves out of forest to feed on broom flowers and clover. Habitat: Kereru prefers native lowland forests but is common in most large patches of vegetation where large fruiting trees are present (i.e. puriri). Has a home range of between 2 40 km, but will only travel approximately 2km betreen patches (Meurk & Hall, 2006). Characteristics: New Zealands only species of endemic pigeon. Identified by large size, general greyish-green colour with pure white breast. Pronounced whistling wingbeat. Food: Eats a wide range of fruits, seeds, flowers and foliage from native and exotic plants. The kereru is an important agent for dispersing seed from many plants, especially seeds from native podocarp trees. The bird will eat a meal of fruit from one plant then fly to a taller tree to digest its food, distributing seed in its droppings along the way. Breeding: (September Feburary) Kereru will nest in patches of native or exotic bush as small as 1 Ha. The nest is a flimsy structure of small twigs loosely crossed. The single white egg is often visible from below. Incubation by both sexes takes days. Clutch overlap may occur if food is plentiful, when the chick in the first nest is attended while a second egg is incubated in a new nest. The disappearance of the kereru would be a disaster for the regeneration of our native forests. (Department of Conservation, 2008) n e c k l a c e 9

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12 M a t r i x T y p o l o g i e s The urban and rural landscape matrixes are the most extensive and dominant land typologies, all other landscape elements can be located within them. This map illustrates how these occur across the Auckland isthmus. Elements of these landscapes such as waterways are situated within each matrix but also cross what could be considered a threshold between them. The rural matrix is predominantly pasture or open green-space, cleared in the past for productive purposes although it is not necessarily still used for production. The urban/suburban matrix is where residential sprawl and city areas are dominant. This mapping is important because base matrix land typologies give spatial context to all other elements that exist in the landscape. Using GIS (Geographic Information System) it is possible to locate and represent these typologies at a coarse-grained scale. This and the following maps in this section were put together in Photoshop using data from GIS at 1:50,000 scale at A0. Rural Matrix Urban/Suburban Matrix Waterways Coastal Rocks/Reef Mud Sand Scale: 1:400, e m e r a l d

13 V e g e t a t i o n T y p o l o g i e s This is a map of vegetation typology; it differentiates between native and exotic plant species in the Auckland region. Native and exotic forests have entirely different frameworks; the plant species that dominate an area dictate how the process of succession takes place. Succession is one of two main factors that shape forests and create vegetation patterns; the other is disturbance. This map is important in understanding the placement of existing habitats for native birds. Kereru will nest in exotic pine forests but native vegetation provides them with fruit food needed to breed successfully. However, the bird won t fly more than 2km from patch to patch (Meurk & Hall, 2006). This image reveals a lack of food vegetation across the urban matrix and areas capable of supporting a breeding pair of Kereru, which require at least 1 Ha of patch vegetation. Rural Matrix Urban/Suburban Matrix Waterways Coastal Rocks/Reef Native Vegetation Exotic Vegetation Scrub Mud Sand Scale: 1:400,000 Mangroves Shelterbelts n e c k l a c e 13

14 P a t c h e s Mapping of vegetation patches in the Auckland region. Patches are a significant factor in the functioning of urban ecology; this map endeavours to represent existing patches across the isthmus. Patches are the remains of fragmented forest conditions. Generally a patch is defined by size and shape, areas of vegetation must be a minimum of 1Ha in size and roughly round in shape to be classed as a patch. Patches have edge and core conditions, in the Auckland region forest edges have been experimentally measured at 50m but can range from 20 to 100m depending on particular disturbances such as wind and human influences (Forman & Gordon, 1986). Rural Matrix Urban/Suburban Matrix Waterways Coastal Rocks/Reef Mud Sand Scale: 1:400,000 Most native forest bird species such as Kereru and Tui need forest or bush patches of 1Ha or more in order to breed. This map shows the lack of significant patches in the urban matrix. < 20m Patch Edge > 100m Patch Core 14 e m e r a l d

15 C o r r i d o r s This is a map of vegetative corridors across the Auckland region. Alongside patches, corridors are key to the functioning of urban ecology. Vegetative corridors are narrow stretches of vegetation that allow fauna to move from patch to patch without leaving a familiar habitat. They connect and sustain ecosystem health and biodiversity. Vegetative corridors are generally between 20 and 100m in width, any wider and it is classed as a linear patch (Forman & Gordon, 1986). Rural Matrix Urban/Suburban Matrix Waterways Mud Sand Scale: 1:400,000 The urban matrix lacks vegetative corridors that are generally focused around waterways. Many urban waterways are capped and where they aren t they are in culverts or very narrow and vegetation is composed primarily of small marginal plant species. These environments may sustain White-Faced Heron while moving through the landscape but not Kereru. < 20m Coastal Rocks/Reef Vegetation Corridors Patch Edge > 100m Patch Core n e c k l a c e 15

16 U r b a n E c o l o g y Mapping of the Auckland isthmus that depicts the relationship between patch/corridor vegetation and social environments. Rural Matrix Mud Scale: 1:60,000 The landscape patterns that have emerged through GIS mapping are very apparent here. There is a distinct division between ecological communities and human settlements, the vegetation is very fragmented and when we consider that the isthmus was once covered in continuous native bush from Waitakere to Hunua, many connections that once were have now been lost. However, the remnants of many of these patches and corridors within the urban matrix are still visible and could theoretically be reconnected with careful planning and design. This is the basis for this design research. Urban/Suburban Matrix Waterways Coastal Rocks/Reef Sand Road Network Main Arterial Corridors This map reveals areas of ecological potential within the urban matrix, which is severely lacking in vegetative patches/corridors. These areas of potential could reconnect forest patches; increase biodiversity and the overall sustainability of the urban matrix. < 20m Patch Edge > 100m Patch Core 16 e m e r a l d

17 6.1 R e f l e c t i o n : This stage of the project has shown how there is a very significant lack of essential patch/corridor networks within the urban landscape matrix in the Auckland City region. There is still, however, an underlying ecological framework in the form of remnant patches and waterways. These could be connected in order to form a new urban ecology that functions in a way that harmonises the conflict between society and ecology. Certain native bird species currently aren t present in many places on the isthmus because they can t get there or the areas can t sustain them. If a corridor strategy were implemented across the isthmus, the arrival of keystone species such as Kereru in areas where they are not currently present would be an indicator of the success of the design. Both the differences and similarities of these birds will add to the complexity of an ecological corridor if developed in a way that supports both species. Especially since both birds are umbrella species, meaning that if they are present then a wide range of smaller birdlife with the same habitual needs will be inhabit the same area simultaneously. I then continued my design research using drawing and mark making in order to gain a better understanding of how the area of study currently works ecologically and how it could work with the development of Heron and Kereru habitats in urban spaces. My research was then refined to define a specific ecological corridor that has been developed to a stage where it could be implemented. The image below is a contextual map showing my chosen study area for the development of an ecological corridor in urban Auckland. I have chosen this area because it is the narrowest part of the isthmus at this scale; it is in close proximity to the Waitakere Ranges where there is a sustainable population of Kereru, and there is visible potential for a corridor scheme at this course grain scale (i.e. waterways, infrastructural corridors etc). As mentioned in my rationale, I have previously studied Heron Park in Waterview, which is a habitat of the White-Faced Heron. I would like to use the habitat of this bird as a driver in the development of this corridor alongside Kereru because of the differences in the habit and distribution of the two birds. The Heron is a wader that will fly short distances between nesting and feeding grounds which include clusters or patches of tall exotic trees, marginal wetlands and estuarine conditions and open grass space. The Kereru is a forest bird and will short distances patch to patch, it will nest in patches of native or exotic forest 1Ha or larger but needs large native fruiting trees in order to sustain breeding. The mappings in this section were made with GIS (Geographic Information System). This has proved to be very effective at a coursegrain scale, have learned a huge amount about the ecology and layout of the Auckland region. However, at a fine-grained scale GIS is considerably less effective. Much of the information is very vague and must be qualified on the ground in order to get a true representation of what is actually present in a particular space. S t u d y A r e a S e l e c t i o n

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20 V e g e t a t i o n / W a t e r w a y s O p e n S p a c e Vegetation and Waterways taken from GIS data. Scale: 1:40,000 Scale: 1:40,000 Open Space in relation to High Traffic Transport Networks taken from GIS data. Existing vegetation. High traffic routes. Open space. Waterway. Railway stations. Social hubs. Estuarine transition zone. Wading bird habitat. Railway route. This map shows areas of significant vegetation and waterways in the area of study, it also depicts estuarine transition zones. Patches support native forest birdlife on the isthmus, waterways provide potential corridors where vegetation is not currently present that could connect these patches. Estuarine transition zones support a variety of marginal birdlife including the White-Faced Heron. Informed by GIS data, this map emphasises the need for an ecological patch/corridor network spanning the isthmus. There is an obvious lack of connectivity in this area. This map shows open space according to the Auckland Regional Council, arterial transport infrastructure and social hubs across the isthmus. Integration of human pattern and process is a vital aspect in the development of an ecological corridor in this area as the dominant matrix type is urban, therefore containing high-density human communities. There seems to be decent amount of open space in this area that could be modified in order to add to the ecological complexity of the concept of a corridor along with street tree planting and possible interventions at social hubs. 20 e m e r a l d

21 H e r o n R a n g e K e r e r u R a n g e Current Heron Range: taken from 1km visual flight radius to and from current suitable habitat. Scale: 1:40,000 Scale: 1:40,000 Current Kereru Range: taken from 2km visual flight radius to and from current suitable habitat. Existing vegetation. Open space. Existing vegetation. Open space. Waterway. Social hubs. Waterway. Social hubs. Estuarine transition zone. Wading bird habitat. Current Heron flight range. Estuarine transition zone. Wading bird habitat. Current Kereru flight range. This map is a drawing of White-Faced Heron immediate flight ranges from open spaces that currently support the habitat of the birds. This was done by using information gathered on the habitat of the Heron in the bird profile section of this report and GIS data gathered to this point to determine which open spaces in the study area would currently support a breeding pair of White-Faced Herons. 1km radius circles, centered on each habitable site, were drawn to represent the heron s 1km immediate flight range. This has been done in order to determine the placement and current habitat zones of the Herons across the isthmus and give an impression of the extensiveness of these habitat zones and where they could be enhanced. The plotting of Heron habitat range has shown that the birds are or have the capacity to traverse the isthmus if need be, there seems to be sufficient habitat conditions in the Auckland regional area to support viable populations of the birds. This makes sense as White Faced Heron are commonly seen in many open space areas in urban areas, usually on the coast. n e c k l a c e This drawing is of New Zealand Pigeon immediate flight ranges from open spaces that currently support the habitat of the birds. This was done by using information gathered on the habitat of the Kereru in the bird profile section of this report and GIS data gathered to this point to determine which open spaces in the study area would currently support a breeding pair of kereru. 2km radius circles, centered on each habitable site, were drawn to represent the kererus s 2km immediate flight range (Meurk & Hall, 2006). This has been done in order to determine the placement and current habitat zones of the Kereru across the isthmus and give an impression of the extensiveness of these habitat zones and where they could be enhanced. This drawing has shown that the Kereru is concentrated on the south and southwest borders of the study area, mostly in the Waitakere Ranges. The bird wont move much more than halfway across the isthmus as there doesn t seem to be any significant food sources or viable nesting sites on the northern side of the isthmus. 21

22 P r e d i c t e d H e r o n R a n g e P r e d i c t e d K e r e r u R a n g e Predicted Possible Heron Range: taken from 1km visual flight radius to & from current and potential suitable habitat. Scale: 1:40,000 Scale: 1:40,000 Predicted possible Kereru Range: taken from 2km visual flight radius to & from current and potential suitable habitat. Existing vegetation. Open space. Existing vegetation. Open space. Waterway. Social hubs. Waterway. Social hubs. Estuarine transition zone. Wading bird habitat. Predicted possible Heron flight range. Estuarine transition zone. Wading bird habitat. Predicted possible Kereru flight range. The two images on this page use the same graphic techniques as the previous page to show the immediate flight range of the White Faced Heron and Kereru from areas of potential habitat. The potential of each area is defined by taking size, shape and location into account. Increasing the habitual range of the birds will in turn increase biodiversity of the isthmus which will add to the underlying ecological strength of the Auckland region. The White-Faced Heron, although common around the coast, also have the ability to live inland near small water bodies. This image qualifies the need for an ecological corridor to connect ecosystem fragments across the isthmus. In comparison to the current Heron habitat flight range image on the previous page, it is obvious the improvement that could potentially be made. This image shows immediate flight range of kereru from areas of potential habitat. Kereru are not currently present in the area extending from New Lynn to Point Chevalier according to the kereru flight range drawing on the previous page. This image depicts how that could change with modifications to open space across the isthmus to incorporate kereru habitat. Compared to the Heron that is currently present throughout the isthmus with restricted flight patterns, the Kereru is non-existent more than a couple of kilometers north of the Waitakere Ranges. Similarly, there is potential for an ecological corridor spanning the isthmus even though it is currently transparent. An extension of Kereru ecology from Titirangi to Meola Reef would create the corridor that this project aims to achieve. 22 e m e r a l d

23 H e r o n H a b i t a t K e r e r u H a b i t a t Nodes of Heron habitat convergence and lineal connections. Scale: 1:40,000 Scale: 1:40,000 Nodes of Kereru habitat convergence and lineal connections. Existing vegetation. Open space. Existing vegetation. Open space. Waterway. Social hubs. Waterway. Social hubs. Estuarine transition zone. Wading bird habitat. Predicted possible Heron flight range. Estuarine transition zone. Wading bird habitat. Predicted possible Kereru flight range. Node of habitat convergence. Lineal connections. Node of habitat convergence. Lineal connections. In both of the drawings on this page, abstract lineal connections between made between nodes of habitat convergence to illustrate the connections that could be made across the isthmus in a very basic way. These nodes are not physical entities; rather they are graphic representations of points of intensity or high bird interaction. These areas are generally at the limits of the bird flight range depicted on the layer below and on the previous page. The lines used to connect each node depict the basic orientation of a possible ecological corridor could span the urban matrix according to each bird. The Heron, having a flight range of 1km has a more complex lineal path than the Kereru, which will fly up to 2km patch to patch. The Heron also tends to stay near waterways where possible compared to the Kereru, which is not restricted by that aspect of the landscape. Plotting these lineal connections between nodes of intensity has allowed me to begin thinking about this corridor as an actuality. Until now it has only existed in the remaining fragments of the original forests that covered the Auckland region centuries ago and the ecological theory that links them. The nodes and lineal connections and bird flight ranges together could be described as the habitat pattern of the White-Faced Heron or New Zealand Pigeon. n e c k l a c e 23

24 H e r o n P a t h s K e r e r u P a t h s Predicted potential Heron flight paths. Scale: 1:40,000 Scale: 1:40,000 Predicted potential Kereru flight paths. Existing vegetation. Open space. Existing vegetation. Open space. Waterway. Social hubs. Waterway. Social hubs. Estuarine transition zone. Wading bird habitat. Potential Heron flight path. Estuarine transition zone. Wading bird habitat. Potential Kereru flight path. How the birds move though their environment is vital to the development of an ecological corridor as it shows exactly where interventions should be made. The habitat design research on the previous three pages is helpful to show whether or not the birds are present in particular areas and what the range of those habitats is or could be, but it does not show how the birds would move between spaces. This drawing is a representation of the predicted flight paths of the White- Faced Heron if sites located as potential heron habitats were realised. According to this diagram, the Heron tends to stick to coastal areas when not traversing the isthmus, when it moves inland it has a fairly broad channel of movement across the landmass. It uses smaller spaces as ecological stepping-stones to hop between larger green spaces. It also seems to move through social hubs like Unitec. This drawing is a representation of the predicted flight paths of the Kereru if sites located as potential New Zealand Pigeon habitats were realised. This diagram shows how Kereru would move north from the Waitakere Ranges up toward Meola Reef through vegetative corridors and forest patches. The bird tends to stick to waterways and edges of open space where there is more likely to be larger vegetation except where patches are present. It avoids areas of high human social interaction. It also seems to stick inland rather than the coast like the Heron. This could be the lack of appropriate food species for the Kereru on the coast. The flight paths of the Kereru are a lot narrower than that of the White- Faced Heron due to the more specific vegetative requirements of the bird. 24 e m e r a l d

25 H a b i t / H a b i t a t O p e n S p a c e S e l e c t i o n Heron and kereru habit and habitat representation. Scale: 1:40,000 Scale: 1:40,000 Selection of open space corridor using heron and kereru habit and habitat. Open space. Potential Heron flight path. Open space. Potential Heron flight path. Social hubs. Potential Kereru flight path. Social hubs. Potential Kereru flight path. Node of habitat convergence. Lineal connections. Node of habitat convergence. Lineal connections. This image is a representation of the pattern and process of both the White-Faced Heron and the Kereru across the Auckland isthmus. The image was formed by layering the Heron and Kereru flight paths to depict both birds in the same environment; the lineal connection diagrams were added to show habitat intensities in relation to the flight tendencies of the birds. Here there is a definite form emerging from the study area. Both the heron and kereru flight paths are centred along one central path that runs from Titirangi north to Meola Reef in a necklace or band that traverses the isthmus. Selected open space. This image is the selection of open space that acts as a part of the corridor defined by bird pattern and process. If these spaces can be modified through a design process that allows the introduction of viable bird habitats to the urban matrix, maybe a functional ecological corridor could be integrated into a cityscape that currently has a very fragmented, unsustainable ecology. n e c k l a c e 25

26 O p e n S p a c e S t e p p i n g - s t o n e s Scale: 1:20,000

27 7.1 R e f l e c t i o n : Open space according to Waitakere City and Auckland City District Plans. The second section of my research report has provided me with an understanding of how the study area works ecologically and how the Heron and Kereru could be integrated into the urban matrix. I have also defined open space areas that will be the basis for an ecological corridor that spans the isthmus connecting Titirangi and Meola Reef as depicted on the opposite page. The loss of vegetative patches, corridors and above ground waterways in the urban matrix is the reason for the lack of biodiversity throughout our city. There seems to be a lot of open space in the study area that could be more effectively used for the purposes of developing an ecological corridor as well as recreation. There are also streetscapes and social hubs such as educational facilities and supermarkets within my study area that could contribute to the complexity of a corridor. Design research has shown that both the White-Faced Heron and the New Zealand Pigeon would benefit considerably from the implementation of an ecological corridor that spanned the isthmus. A study of the pattern and process or habitat and habit associated with the birds has revealed trajectories, tendencies and destinations that all support the creation of such a corridor. The tendency of the Heron to stay near bodies of water could mean the incorporation of permanent or ephemeral wetlands into public space. Larger public open space could have forest patch elements introduced or developed to give Kereru a destination; or change trajectories to bring them into social hubs where they could interact with people and kindle public interest and support of urban ecological principles. The next stage of the project is development of a functional habitat corridor using the selected open space on the opposite page as a template. I will use data I have gathered on the ecology of the Auckland region, the habits/habitats of the White Faced Heron and the Kereru and relate it to the current Waitakere City Council and Auckland City Council district plans. Using this process I should be able to make additions to the current zoning of the selected open space that will promote the development of an ecological corridor that extends from Titirangi to Meola Reef. Later in the project I will be looking at how a combination of the original analysis data and the new zoning strategy of the corridor can produce a design for the area that stretches from Heron Park up to the Great North Road motorway interchange, including Oakley Creek Esplanade. This design should be unique, exciting open space that meets zoning requirements and effectively integrates ecology into the city. n e c k l a c e 27

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30 C u r r e n t Z o n e s S i z e / A r e a Scale: 1:40,000 Open Space to be Incorporated into Ecological Corridor as zoned by Auckland City District Plan. Scale: 1:40,000 Open Space to be Incorporated into Ecological Corridor classified by size/area. Zone 2: Informal Recreation Zone 4: Community Area >5Ha Area <1Ha Zone 3: Organised Recreation Zone 5: Leisure Area 1-5Ha The selected open space sites that make up the basis for my ecological corridor extend into two urban districts. Darker part of the aerial maps above is Waitakere City and the lighter is Auckland City. As I have not had time to properly review the Waitakere District Plan, the zones depicted here are all classed according to the Auckland City District Plan Isthmus Section. The zone additions that will be made in order to create the ecological stepping-stones that are required to generate a functional habitat corridor for the White-Faced Heron and Kereru are the same in the Waitakere and Auckland areas. The open space zones according to the Auckland City District Plan are: Open Space 1 - Conservation (i.e. indigenous forest patches) Open Space 2 - Informal Recreation (i.e. Heron Park) Open Space 3 - Organised Recreation (i.e. golf courses) Open Space 4 - Community (i.e. community hall grounds) Open Space 5 - Leisure Facilities (i.e. Auckland Zoo) This map depicts the areas of the open spaces selected to be part of the Emerald Necklace habitat corridor. The three separate area ranges shown on this plan allow me to make judgements as to the capacity of the spaces. This project is the about incorporation of ecological stepping-stones into existing open spaces, many of which are currently public recreational spaces. I am not replacing recreational space with bird habitat; I am integrating the two and exploring how they can work together. This image shows that there is sufficient area in enough of the selected open space to form an ecological corridor without compromising the useability of each space. I hope, in fact, that the introduction of White- Faced Heron and Kereru by design ecology could increase the aesthetic interest of these areas and increase use. 30 e m e r a l d

31 8.1 Z o n e C l a s s i f i c a t i o n : Open spaces have an important role in the sustainable management of natural and physical resources. The quality of the environment can be maintained and enhanced by managing open space areas for heritage preservation, and by providing locations which will allow ecosystems to function in their natural state. (Auckland City District Plan Isthmus Section, Part 9.1) n e c k l a c e 31

32 Scale: 1:20,000

33 8.2 Z o n i n g S c h e m e : The areas defined as being part of the Emerald Necklace should be subject to the guidelines applied to the five open space zones in accordance with the Auckland City District Plan Isthmus Section. also Each of these areas will now be subject to additional zoning criteria that is specific to the Emerald Necklace concept. This concept is an ecological corridor design strategy driven by the habits/habitat of the White Faced Heron and Kereru bird species. It integrates human activity and ecology at the spaces defined on the opposite page. There is a Zoning Chart on the next page that goes into more depth about exactly what additions are to be made in each of the spaces located in this plan. Summary of Zone Additions: Open Space 1 Conservation a) (Size: any) Re-vegetation or restoration projects should use exotic pioneer species where appropriate in order to create temporary bird beacons and nesting habitats until native flora has suitable structure to perform these tasks. Open Space 2 Informal Recreation a) (Size: <1 Ha) Should contain small clusters of native and exotic beacon vegetation where appropriate. Should contain small clusters of native food vegetation. b) (Size: 1 to 5 Ha) Should contain small clusters of native and exotic beacon vegetation where appropriate. A minimum of 20% of the area should consist of clusters of native food vegetation. A small portion of the grass area should be contoured in a way that allows rainwater to form shallow pools or ephemeral wetlands. c) (Size: >5 Ha) Should contain large clusters of native and exotic beacon vegetation where appropriate. A minimum of 20% of the area should consist of clusters and patches of native food vegetation. A small portion of the grass area should be contoured in a way that allows rainwater to form shallow pools or ephemeral wetlands. Open Space 3 Organised Recreation a) (Size: <1 Ha) Should contain small clusters of native and exotic beacon vegetation where appropriate according to the use of the site. Should contain small clusters of native food vegetation where appropriate. b) (Size: 1 to 5 Ha) Should contain small clusters of native and exotic beacon vegetation where appropriate according to the use of the site. Should contain small clusters of native food vegetation where appropriate. c) (Size: >5 Ha) Should contain many small to large clusters of native and exotic beacon vegetation where appropriate according to the use of the site. A minimum of 20% of the area should consist of clusters and patches of native food vegetation. Open Space 4 Community a) (Size: <1 Ha) Should contain small clusters of native and exotic beacon vegetation where appropriate. Should contain small clusters of native food vegetation where appropriate. b) (Size: 1 to 5 Ha) Should contain small clusters of native and exotic beacon vegetation where appropriate. Should contain small to large clusters of native food vegetation where appropriate. c) (Size: >5 Ha) Should contain large clusters of native and exotic beacon vegetation where appropriate. Should contain large clusters of native food vegetation where appropriate. Open Space 5 Leisure Complexes a) (Size: any) Any amenity planting should be done in a way that is beneficial to the ecology of the area and the structure of the Emerald Necklace. (i.e. Property boundaries should be planted with appropriate native or exotic beacon vegetation, gardens should contain appropriate native food species). n e c k l a c e 33

34 8.3 Z o n i n g C h a r t : 34 e m e r a l d

35 n e c k l a c e 35

36 36 e m e r a l d

37 9.0 E m e r a l d N e c k l a c e n e c k l a c e 37

38 Scale: 1:20,000

39 9.1 P r o p o s e d H a b i t a t C o r r i d o r Vegetation. Waterways. Open Space (As classified by District Plan, plus supporting open space in close proximity). Proposed streetscape enhancement to incorporate bird attracting tree species, strengthening the corridor. The image on the opposite page is a rendering of the Emerald Necklace functional habitat corridor. This plan shows how the Necklace will be incorporated into the social network of the isthmus. The planting of streetscapes with appropriate vegetation could strengthen the overall ecology of the Necklace as well as integrate human infrastructure in the project. The ecological success of the corridor will not only benefit the urban matrix within the boundaries of the ecological stepping-stones but will spill out into surrounding potential landscapes such as the Unitec campus. These new landscapes are attractive to humans too, and provide interestingly designed green areas (right in the middle of cities) where visitors can encounter and interact with beings that are often barely registered by the public at large (R. Barnett) n e c k l a c e 39

40 Scale: 1:20,000

41 9.2 P r e d i c t e d F u n c t i o n of H a b i t a t C o r r i d o r : Vegetation. Waterways. Open Space. Proposed streetscape enhancement. Potential flight paths. This image is a graphic representation of how the Emerald Necklace ecological corridor will function according to the habitual tendencies of the White-Faced Heron and the Kereru. The organic, flowing entity is the potential flight paths of both the Heron and Kereru. With the implementation of an ecological stepping-stone strategy across the isthmus I have created a habitat corridor that will cater for the needs of both the White-Faced Heron and the New Zealand Pigeon or Kereru. The success of this concept will be able to be measured by birdlife diversity and population increases in the area of study. This will be especially noticeable in the case of the Kereru, which is currently not present in the north of the subject area due to habitat destruction and loss of ecological connectivity. The arrival of this particular bird in the centre and northern end of the Emerald Necklace would indicate the success of the project as a whole. n e c k l a c e 41

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43 10.0 S i t e D e s i g n n e c k l a c e 43

44 10.1 A n a l y s i s D a t a I n t e r p r e t a t i o n : The first phase of design for my chosen concept development area is the interpretation of my Heron and Kereru nalysis data from the previous stages of my research. The image below is the portion of the data that interacts with my site that stretches from Heron Park up to the Great North Road motorway interchange, including Oakley Creek Esplanade. The abstract graphic data contains information about Kereru and Heron habitat range, flight paths, and bird interaction. In order to incorporate a human element into the design process, since this is urban habitat design, I have added an infrastructure extension layer to the image. This is a simple move whereby the road network in and around the concept area has been extended into a grid that weaves in and through and out of it. The idea is that this data could offer complexity to the design that better integrates the ecology of the Heron and Kereru into the urban matrix. The image on the opposite page is this graphic data imposed on the site itself with the existing contours. The next move is to interpret how each of the elements present in the data would interact with the site. Represented graphically on the site, these interactions may create topographical changes, areas of possible vegetation, recreational spaces etc G r a p h i c D a t a

45 I m p o s e d G r a p h i c D a t a n e c k l a c e 45

46 I n t e r p r e t e d G r a p h i c D a t a 46 e m e r a l d

47 This drawing is an amalgamation of the graphic data produced during the bird analysis phase of the project and topography and urban fabric of the surrounding neighbourhoods. The graphic data has been interpreted by the connections it makes with both the topography and extensions of the urban matrix into the site from the surrounding suburbs. These urban axes mesh over, under and into the graphic data sets providing a structural realism that grounds the abstract forms produced by mapping in the early stages of this project. n e c k l a c e 47

48 10.2 C o n c e p t D e v e l o p m e n t : high The three spaces within the area of study are very spatially distinct from one another. For this reason, I chose to make interventions of different scales or intensities at each of the three sites. This shows several levels of urban design possibilities when incorporating an ecological machine such as a habitat corridor into public space. low moderate 48 e m e r a l d

49 The largest of the three spaces is the Great North Road motorway interchange; it is also the most isolated from foot or vehicular traffic. However it is currently used as feeding grounds by the White Faced Heron, which moves up from Heron Park to the area seeking nourishment. There is currently no significant vegetation on the site, apart from a few large macrocarpa and a very sparse attempt at revegetation of the ephemeral streams that flow through the space on both sides. This area is also the closest to a town centre (Pt Chevalier) and has the busiest edge conditions as it is surrounded on all sides by major arterial roads. The interchange has potential to become a large urban bird haven, as it has a fortress-like barrier against pests in the form of busy roads, it is large enough to contain a forest system capable of supporting breeding pairs of the Heron and/or Kereru. There is ephemeral water at the site most of the year and plenty of grass areas that the Heron loves to feed in. There is, however, little to support lowland forest birds like the Kereru as there is almost no vegetation on which to feed or shelter in. This particular site is also severely underutilized as a part of the urban matrix. The area locked in by the onramps/off-ramps and the northwestern motorway itself is basiclly dead space. It is not used for any purpose other than motorway maintenance and construction. This has allowed the White Faced Heron to become the most frequent visitor to the site, but because of a lack of suitable breeding environs they do not reside there. Kereru are not present in the area at all as they cannot move far enough across the isthmus from either the Waitakere Ranges in the west or the Hunua Ranges in the east. The proposed design for the Great North Road motorway interchange has the highest level of designed modification of the three spaces this report focuses on. Driven by the development of the Emerald Necklace and how this is woven into the urban fabric of Auckland city, the space focuses on providing the White Faced Heron with areas to nest and breed and at the very least, food vegetation for the native Kereru. great north road motorway interchange n e c k l a c e 49

50 The second of the three areas in design is the Oakley Creek Esplanade; this is the low intervention area. This space already functions as part of the Emerald Necklace as it is on the ridgeline of the Oakley Creek catchment, which is one of the largest stands of native bush along a stream edge left in the city. The issue with this site in relation to Kereru for example, is that the creek and surrounding vegetation is tucked away down in the bottom of a gully. So, although there is plenty of Kereru food in this area, there are no Kereru because they cannot see it. oakley creek esplanade 50 e m e r a l d

51 heron park The third space is Heron Park in Waterview. This 11Ha site is currently the home to several breeding pairs of White Faced Heron. This is Due to the large exotic pine (Pinus radiata) that covers over two hectares of the site providing appropriate nesting conditions. These pine have the capacity to function as pioneer species, eventually allowing taller native trees such as kahikatea to succeed them and form a tall native canopy that acts as a bird beacon. n e c k l a c e 51

52 Bird Beacon Meadow Plum Orchard Food Forest Titoki Grove Gateway Species Ephemeral Wetland Kowhai Grove Pedestrian Walkway 52 e m e r a l d

53 10.3 D e s i g n O u t c o m e s great north road motorway interchange Large exotic species such as Pinus radiata which have a fast growth rate have been used as pioneer species for Bird Beacon areas. These trees will be succeeded by tall natives like Podocarpus dacrydioides Kahikatea. This perspective shows the visual connection with the Waitakere Ranges, a source of biodiversity for the Auckland region, illustrating the interchange s position within the ecological matrices of Auckland. Underplanting consists of variety of native food species that will provide appropriate food types during different seasons. Large gabions filled with basult provide habitats for many species of insects and lizards, which are food sources for many birds, including the White Faced Heron. a B A Park Entrance a Park Entrance Park Entrance Bird Beacon Park Entrance Ephemeral Wetland Bird Beacon Park Entrance Titoki Grove Ephemeral Wetland b Puriri Grove Park Entrance A Kowhai Grove Titoki Grove B b n e c k l a c e Urban forests, patches of tall trees hang over motorists, roadway arches over an ephemeral wetland, allowing ground dwelling wildlife a corridor under infrastructure. 53

54 Section B - B 1 : 1500 great north road motorway interchange Section A - A 1 : e m e r a l d

55 Gabion walls provide habitats for insects and lizards, which provide food for birds. Ridgeline Cluster C Pedestrian Linkage Heron Feeding c Pedestrian Plaza Oakley Creek Buffer C Detail of main pedestrian walkway on section C - C, 1:100 oakley creek esplanade Streetscape enhancement Bird Beacon cluster on the side of Great North Road, on the ridgeline trees are visible from large distances. community plaza c n e c k l a c e 55