hanski’s incidence function model for urban biodiversity planning

Hanski’s incidence function model for urban biodiversity

planning

Laura Graham, ESRC funded PhD candidate

Supervisors: Prof. Roy Haines-Young Dr. Richard Field

Background

Importance of urban ecosystems to both human well-being and biodiversity prevalent in conservation policy

Lawton Report implies a need for conservation planning at a landscape level

Does not seem to have formed part of local authority policy

Research Aim

To investigate the applicability of the IFM to urban biodiversity planning at landscape scale

by testing suitability of available data through sensitivity analysis

To use the IFM to explore policy questions of both local and national relevance

Spatially realistic metapopulation model

Low data requirements

Urban landscapes are fragmented

Incidence function model (IFM)

Incidence function model (IFM)

Time (t) = 0

Incidence function model (IFM)

Time (t) = 0 t = 1

Incidence function model (IFM)

Time (t) = 0

t = 2

t = 1

Incidence function model (IFM)

Time (t) = 0

t = 2

t = 1

t = 3

Incidence function model (IFM)

Time (t) = 0

t = 2

t = 1

t = 3

Implications of data quality

Mis-estimated patch areas

Habitat patches not identified

False absences in species datasetMoilanen, 2002

Study Site and Landscape Data

Data from Nottinghamshire Birdwatchers

Map shows surveyed grid squares (1998-2011)

Data from 1998-2009 grouped into 3 survey windows

Species Data

Patch Occupancy

1. Survey data

2. Interpolated data (kriging)

3. Random at surveyed %

4. Random at interpolated %

1.

4.

2.

3.

Blackbird (Turdus merula)

Time

Patc

hes O

ccup

ied

← Effects of occupancy level →

← Effects of spatial structure →

Photo credit: Oystercatcher on

flickr

Corn Bunting (Miliaria calandra)

Time

Patc

hes O

ccup

ied

← Effects of occupancy level →

← Effects of spatial structure →

Photo credit: Steve Riall on

flickr

Marsh Tit (Poecile palustris)

Time

Patc

hes O

ccup

ied

← Effects of occupancy level →

← Effects of spatial structure →

Photo credit: Steffen Hannert

Parameterise on subset of survey data

Parameterise on subsets comprising grid squares surveyed in both 1st and 2nd survey window

Run model for each set of parameters

Results of subsetting

Patc

hes O

ccup

ied

Time

Conservation policy implications

If IFM has potential to be used to for urban biodiversity planning:

Need for intensive monitoring and surveying

Need for more joined up and centralised databases

Compare relative effects of varying management scenarios