1 Sensitive to human impact and Sensitive to human impact and - PDF document

• Why do badgers • Why do badgers matter? Badger ecology in coastal California: matter? Badger ecology in coastal California: implications for corridor design implications for corridor design • Badger ecology Badger ecology • – Movement – Movement Jessie Quinn Jessie Quinn – Habitat – Habitat Ph.D. Candidate Ph.D. Candidate preferences preferences UC Davis Ecology Graduate Group UC Davis Ecology Graduate Group CDFG/UCD WHC Resource CDFG/UCD WHC Resource • What makes a What makes a • Assessment Program Competitive Assessment Program Competitive Grant Project, 2004- Grant Project, 2004 -2007 2007 good badger good badger corridor? corridor? • • Listed as a Species of Special Concern Listed as a Species of Special Concern • Sensitive to human impact and • Sensitive to human impact and development development • Not often considered in environmental Not often considered in environmental • review process review process • • How should they be considered?? How should they be considered?? *Crooks 2002 *Crooks 2002 1

• • Sensitive to human impact and Sensitive to human impact and • Sensitive to human impact and • Sensitive to human impact and development development development development • Representative of the grassland Representative of the grassland • Representative of the grassland Representative of the grassland • • community community community community • Wide • Wide- -ranging carnivore: spatial factors ranging carnivore: spatial factors important important Research in California Research in California • • California Department of Fish and Game California Department of Fish and Game UC Davis Wildlife Health Center Resource UC Davis Wildlife Health Center Resource Assessment Program 2003 Assessment Program 2003- -2007 2007 • • GOAL: Determine conservation status of badgers in GOAL: Determine conservation status of badgers in California California • • Population distribution Population distribution • • Behavioral ecology Behavioral ecology • PRODUCTS: • PRODUCTS: • • Species status report Species status report • • Reassessment of CWHR model for badgers Reassessment of CWHR model for badgers 2

About American badgers About American badgers About About badgers badgers… … • Taxidea taxus Taxidea taxus (4 (4 • subspecies) subspecies) • Range across the Range across the • • Mustelids Mustelids • western U.S., western U.S., • 6 species worldwide 6 species worldwide • southern Canada, southern Canada, and northern and northern • Carnivorous Carnivorous- -omnivourous omnivourous • Mexico Mexico • Semi Semi- -fossorial fossorial • • Associated with • Associated with grasslands, open grasslands, open habitats habitats • Semi • Semi- -fossorial fossorial About American badgers About American badgers Movements Movements • • Females ~ 7 kg, Females ~ 7 kg, • Movements vary • Movements vary… … males ~ 15 kg. males ~ 15 kg. 2 km 2 2 km 2 >200 km >200 km 2 2 • • 1 1- -4 kits per year (avg. 4 kits per year (avg. 2). 2). • • Polygamous Polygamous 100 km dispersal 100 km dispersal • • Delayed implanters Delayed implanters • Solitary • Solitary • In California, home • In California, home • • Mainly carnivorous Mainly carnivorous ranges between 1 ranges between 1 • • Eat burrowing Eat burrowing rodents, lizards, rodents, lizards, and 24 km 2 and 24 km 2 birds and bird eggs birds and bird eggs 3

• Badgers known to be present Movements Movements • Diverse habitats • Roads • Irrigated agriculture • Home ranges larger • Home ranges larger where prey is where prey is • Residential development patchier patchier • Home ranges larger Home ranges larger • 15 km where population where population density is lower density is lower Home range size Home range size 20 Kernel MCP 15 Kilometers^2 10 5 0 150 400 440 880 170 310 340 370 730 780 Animal ID 5 km 4

Habitat preference Habitat preference Habitat preference Habitat preference • • Habitat preference Habitat preference • Vegetation type Vegetation type • – – Locations within Locations within • Distance from Distance from • 2 km 2 km home range home range roads roads compared to home compared to home range composition range composition • Distance from • Distance from rd order) (3 rd order) (3 trails trails – – Composition of home Composition of home 12 km 12 km 12 km 12 km range compared to range compared to composition of study composition of study nd order) site (2 nd site (2 order) – Dens, active, and Dens, active, and ! ! ! ! – ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! pooled locations pooled locations ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! Habitat selection Habitat selection Habitat selection Habitat selection • Den locations Den locations • Active locations Active locations • • – Preferred to be – Preferred to be – – Preferred to be Preferred to be 2 km 2 km distant from distant from distant from distant from roads, trails roads, trails roads roads – – Preferred Preferred – – No preference No preference scrub, scrub, for other for other grassland, grassland, factors factors riparian/ marsh riparian/ marsh – Least preferred Least preferred – urban and oak urban and oak woodland woodland 5

Habitat selection Habitat selection Movement • • All locations All locations paths – – Preferred to be Preferred to be 2 km distant from distant from roads, close to roads, close to • Up to 2 km/night trails trails • Will cross busy road – – Preferred annual Preferred annual grassland, native grassland, native 12 km 12 km • Perhaps follow linear grassland, scrub grassland, scrub landscape features? – Least preferred Least preferred – • Or don’t follow them urban and urban and ! ! ! ! ! ! ! ! !! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! at all. ! ! ! ! ! ! ! ! maritime chaparral maritime chaparral ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! ! 1 km Implications for corridor design Implications for corridor design ! ( ( ! ( ! ( ! ( ! • Badgers will site their home ranges in Badgers will site their home ranges in • ( ! grasslands, but can use a mosaic of grasslands, but can use a mosaic of habitats within it habitats within it ( ! ! ( – – More selective for den locations More selective for den locations ! ( ( ! ( ! ( ! • Habitat itself won • Habitat itself won’ ’t serve as a t serve as a “ “funnel funnel” ” • More important to have More important to have • ( ! ( ! ! ( ! ( – – A very wide corridor A very wide corridor ( ! ( ! ! ( – And/or many crossings with physical – And/or many crossings with physical ( ! funnels funnels ( ! ( ! 100 m 6

Implications for corridor design Implications for corridor design Implications for corridor design Implications for corridor design • Fortunately Fortunately… … • Highest amounts of badger movement Highest amounts of badger movement • • are likely to be in the late summer and are likely to be in the late summer and – Badger activity is easy to locate and – Badger activity is easy to locate and early fall identify identify early fall � You put a corridor � You put a corridor near where they are near where they are • Very little movement in the winter Very little movement in the winter • – Male badgers may track each other Male badgers may track each other’ ’s s – • Female badgers will be denning or with Female badgers will be denning or with • movements movements kits February – – July July kits February � � Once one animal uses the corridor, others Once one animal uses the corridor, others may follow – Disturbance in core area and corridor – Disturbance in core area and corridor may follow should be minimized during this time should be minimized during this time What does a badger What does a badger burrow look like? burrow look like? Badger: Badger: possible possible sleeping sleeping den den coyote coyote 10- 10 -12 inches 12 inches Badger: Badger: hunting hunting holes holes ~3 feet ~3 feet 7