Foraging and Nesting Habits of Woodpeckers in a Subalpine Forest - PowerPoint Presentation

Slide1

Foraging and Nesting Habits of Woodpeckers in a Subalpine Forest

Alex GoldsmithWinter Ecology – Spring 2016CU Mountain Research Station Slide2

Background

Woodpeckers are keystone species Create homes Insect control

R

elationship between woodpeckers and bark insects

Snag selectionSnags with large DBH and height preferredSlide3

The Question

Are certain criteria influencing snags woodpeckers utilize for cavity construction and foraging?Insect presenceDBHHeight

Expected results

Woodpeckers are most active amongst snags with insect presence.

Woodpecker activity will be influenced by snag height and DBH.Slide4

Study area

Niwot Ridge Biosphere Reserve3,140 m elevation (10,300’)

Species involved

Downy Woodpecker (

Picoides pubescens)

Hairy Woodpecker (

Picoides

villosus

)Subalpine Fir (Abies lasiocarpa)Engelmann Spruce (Picea engelmannii)Slide5

Methods

50m x 50m plot5 transects Snags recorded and measuredDBHHeight

Woodpecker presence and activity

Insect presence

DBH and Height grouped into categories for Chi2Slide6

Results

32 snags 12 with woodpecker foraging2 with woodpecker cavities24 with bark insects

92% of snags with woodpecker activity had insect boreholesSlide7

Hypotheses

Does snag DBH affect woodpecker cavity presence?H0: Snag DBH does not affect woodpecker cavity presence

H

a

: Snag DBH does affect woodpecker cavity presenceDoes snag height affect woodpecker cavity presence?H0

: Snag

height

does not affect woodpecker cavity presence

H

a: Snag height does affect woodpecker cavity presenceDoes snag DBH affect woodpecker foraging behavior?H0: Snag DBH does not affect woodpecker foraging behavior

H

a

: Snag DBH does affect woodpecker

foraging behavior

Does snag height affect woodpecker foraging behavior?

H

0

: Snag DBH does not affect woodpecker

foraging behavior

H

a

: Snag DBH does affect woodpecker

foraging behaviorSlide8

P=0.44

P=0.53Slide9
Slide10

Discussion

Height and DBH not significant factors in snags woodpeckers use for foraging and cavitiesLack of differentiation between Downy and Hairy woodpeckerPatterns

suggest need for more samples

Most foraging in tall snags

Most foraging in snags with large DBHMost cavities in snags with large DBH

O

verall forest composition more important than individual snag?Slide11

Summary

Insect presence most important factorSnag height and DBH not significant indicators of woodpecker cavities or foragingLarger sample

Forest composition

Woodpeckers important as keystone speciesSlide12

Acknowledgements

First and foremost, Tim Kittel for his continued support and for equipping me with the knowledge and resources to pull this offArvind Punjabi for helping me identify different signs of woodpeckersDerek Sweeney as a constant source of humor and his encyclopedic knowledge of everything ecology

All of YOU for being awesome and making this class worth every moment!Slide13

Works Cited

Conner, R. and C. Adkisson. 1977. Principal Component Analysis of Woodpecker Nesting Habitat. The Wilson Bulletin. 89: 122-129. URL: http://www.jstor.org/stable/4160877

Koplin

, J. 1969.

The Numerical Response of Woodpeckers to Insect Prey in a Subalpine Forest in Colorado. The Condor 71: 436–438. DOI: 10.2307/1365747Ohmann

, J.,

McComb

, W., and A.

Zumrawi

. 1994. Snag Abundance for Primary Cavity-Nesting Birds on Nonfederal Forest Lands in Oregon and Washington. Wildlife Society Bulletin. 22: 607-620. URL: http://www.jstor.org/stable/3783086Ripper, D., Bednarz, J., and D. Varland. 2007. Lanscape Use by Hairy Woodpeckers in Managed Forests of Northwestern Washington.

Journal of Wildlife Management.

71: 2612-2623.

DOI:

10.2193/2005-487

Yeager, L. 1955. Two Woodpecker Populations in Relation to Environmental Change. The Condor 57: 148–153. DOI: 10.2307/1364863

.