Introduction

Methods

Literature Cited

Questions

Roles of Nest Cavities

Management Implications

Microclimate Selection

Importance

Research Question

Hypotheses and Predictions

Primary cavity nesters are

keystone species for forest

biodiversity and indicators of

ecosystem health 1, 3, 6, 9, 13, 14

Cavities provide protection from

predators and external

environment 14, 15

Cavity availability limits non-

excavating cavity users 3, 14

Cavity nesters form complex webs 2, 9

Guild management benefits many species 3, 6, 14

Suitable snag retention critical to management 1

Live-unhealthy and recently dead trees are most

often selected by cavity excavators2

External decay profile poor indicator of internal

decay 2

Cavity location and

depth influenced by

pockets of decay 2,13, 15

Snag properties and

surrounding

environment affects

cavity microclimate 1

Microclimate extremes

influence fitness costs to

nestlings and adults 11

Cavity selection for stable/moderate

thermal regimes correlated with… 10, 11

Tree health 3, 13

Diameter at cavity height 3, 4, 13

Cavity orientation 3, 13

Entrance diameter 10

Optimal environments may…

› Reduce energetic costs to young 7, 11

› Decrease bacterial growth 12

› Increase growth rates of young 5

Studies have yet to consider wood density and hardness

as influencing microclimate within the cavity

Microclimate attributed to buffering capacity 4

Microclimate correlated to tree health, diameter at

cavity height, and orientation 14

Climate change could cause shifts in snag selection

Microclimate analysis can be used to understand:

› Influence of hardness on thermal regimes

› Aspects of ideal microclimate

› Forest management approaches

How do external and internal

factors influence microclimate

(temperature) created by the

cavity?

› External factors: canopy cover,

external temperature, and

diameter at cavity height

› Internal factors: wood density,

cavity depth (horizontal and

vertical), and entrance diameter

Microclimate will be influenced by canopy

cover, wood density, diameter at cavity

height and entrance diameter.

Moderate thermal regime as a result of…

› Small entrance diameter

› Increased amount of internal decay

› Increased diameter at cavity height

› Increased canopy cover

***Orientation may be important, however,

influences can be counteracted by canopy

cover

Data Collection

Study Area

My Data

Data Analysis

Previous study by

Teresa Lorenz in 2013:

260 cavities

Tree species

Excavator species

Snag hardness

Cavity height

Orientation

Location

And much more…

Study sites concentrated: 260 110 cavities› Elevation below 4000 ft

› Cavities between 3 and 25 ft high

› Intact (not depredated)

› Significant tree species

› Significant Study areas

› Localized proximity

Figure 1. Four major study areas indicated by the clustered points. Green points indicate cavities in the Wenas study area, yellow points indicate those of the Nile study area, purple points represent Rattle, and blue represents Rimrock. These areas occur within or near the Okanogan-Wenatchee National Forest on the eastern slopes of the Cascade Mountain Range, Washington, USA. These areas were plotted using Google Earth.

Yakima

Internal Factors of MicroclimateEntrance

diameter

Hardness

Cavity vertical and horizontal depth

Temperature using iButtons

External Factors of

Microclimate

Temperature with

iButtons outside

Diameter at cavity

height 13

Canopy cover

(modified

hemispherical

approach) 8

Statistical Analysis Software SAS 9.0 Paired T-Test: temperature inside and outside

cavity

Paired T-Test: diameter at cavity height and depth measurements

Analysis of best fit models (AIC): internal and external affects on temperature difference

1Aitken, K. E. H., and K. Martin. 2004. Nest cavity availability and selection in aspen-conifer

groves in a grassland landscape. Canadian Journal of Forest Research 34:2099-

2109.2Blanc, L. A., and K. Martin. 2012. Identifying suitable woodpecker nest trees using decay

selection profiles in trembling aspen (Populus tremuloides). Forest Ecology and

Management 286:192-202.3Cockle, K. L., K. Martin, and G. Robledo. 2011. Linking fungi, trees, and hole-using birds in

a Neotropical tree-cavity network: Pathways of cavity production and

implications for conservation. Forest Ecology and Management 264:210-219.4Coombs, A.B., J. Bowman, and C.J. Garroway. 2010. Thermal properties of tree cavities

during winter in a northern hardwood forest. Journal of Wildlife Management

74:1875-1881.5Dawson, R.D., C.C. Lawrie, and E.L. O’Brien. 2005. The importance of microclimate

variation in determining growth and survival of avian offspring: experimental

evidence from a cavity nesting passerine. Oecologia 144:499-507.6Drever, M. C., and K. Martin. 2009. Response of woodpeckers to changes in forest health

and harvest: Implications for conservation of avian biodiversity. Forest Ecology

and Management 259:958-966.7Howe, S., D.L. Kilgore Jr., and C. Colby. 1987. Respiratory gas concentrations and

temperatures within nest cavities of the northern flicker (Colaptes auratus).

Canadian Journal of Zoology 65:1541-1547.8Jonckheere, I., S. Fleck, K. Nackaerts, B. Muys, P. Coppin, M. Weiss, and F. Baret. 2004.

Review of methods for in situ leaf area index determination: Part I. Theories,

sensors and hemispherical photography. Agricultural and Forest Meteorology

121:19-35.

9Martin, K., and J. M. Eadie. 1999. Nest webs: A community-wide approach to the

management and conservation of cavity-nesting forest birds. Forest Ecology and

Management 115:243-257.10Rhodes, B., C. O’Donnell, and I. Jamieson. 2009. Microclimate of natural cavity nests

and its implications for a threatened secondary-cavity-nesting passerine of New

Zealand, the south island saddleback. The Condor 11:462-469.11Robertson, B.A. 2009. Nest-site selection in a postfire landscape: Do parents make

tradeoffs between microclimate and predation risk? The Auk 126:500-510.12Ruiz-De-Castañeda, R., A.I. Vela, S. González-Braojos, V. Briones, and J. Moreno. 2011.

Drying eggs to inhibit bacteria: Incubation during laying in a cavity nesting

passerine. Behavioural Processes 88:142-148.13Savignac, C., and C.S. Machtans. 2006. Habitat requirements of the Yellow-bellied

Sapsucker, Sphyrapicus varius, in boreal mixedwood forests of northwestern

Canada. Canadian Journal of Zoology 84:1230-1239.14Wiebe, K.L. 2001. Microclimate of tree cavity nests: Is it important for reproductive

success in Northern Flickers? The Auk 118:412-421.15Wesolowski, T. 2011. “Lifespan” of woodpecker-made holes in primeval temperate

forest: A thirty year study. Forest Ecology and Management 262:1846-1852.16Zahner, V., L. Sikora, and G. Pasinelli. 2012. Heart rot as a key factor for cavity tree

selection in the black woodpecker. Forest Ecology and Management 271:98-

103.

Slide 1: http://yakamafish-nsn.gov/restore/projects/woodpecker-nest-site-

characteristics-managed-ponderosa-pine-stands,

http://www.sierraforestlegacy.org/FC_SierraNevadaWildlifeRisk/Biodiversity%20

Indicators.php

Slide 2: http://wdfw.wa.gov/living/snags/

Slide 4: http://www.art.com/products/p357041821-sa-i4007984/gary-meszaros-

female-hooded-merganser-in-its-tree-hole-nest-cavity-lophodytes-cucullatus-

north-america.htm, http://northwestnaturalmoments.blogspot.com/2011/11/red-

squirrel-peeking-out-of-nest-hole.html, http://yakamafish-

nsn.gov/restore/projects/western-bluebird-nest-survival-managed-ponderosa-pine-

forests

Slide 5: http://www.faculty.biol.vt.edu/walters/lblanc/CurrentResearch.html

Slide 6: http://en.wikipedia.org/wiki/Selection_cutting,

http://www.nps.gov/fire/wildland-fire/learning-center/fireside-chats/history-

timeline/operational-inventions-and-developments.cfm

Slide 7: http://www.peeniewallie.com/2008/07/house-wren-1.html

Slide 8: http://fletcherwildlifegarden.wordpress.com/2013/11/08/early-november-

2013-at-the-garden/black-capped-chickadee-nest-cavity-in-birch-tree/

Slide 9: http://jimmccormac.blogspot.com/2011/11/red-cockaded-

woodpecker.html, http://pictures.n3po.com/Images/Eggs-in-bird-s-nest-in-tree-

cavity.jpg.html

Slide 11: http://www.faculty.biol.vt.edu/walters/lblanc/CurrentResearch.html

Slide 10: http://goeddelphotography.com/portfolio/birds/woodpeckers/northern-

flicker-exiting-nest-cavity/

Slide 14: http://yakamafish-nsn.gov/restore/projects/woodpecker-nest-site-

characteristics-managed-ponderosa-pine-stand,

http://lafeber.com/wildlife/scarlet-macaws-in-la-moskitia-honduras-what-we-

found/

Slide 15: http://johnsonmatel.com/blog1/2009/02/ponderosa_pines.html

Slide 16: Google Earth©

Slide 17: http://www.fws.gov/carolinasandhills/rcw.html,

http://www.embeddeddatasystems.com/DS1921G-F5--Thermochron-iButton-

40C-thru-85C_p_5.html, Figure 6. Outline of vertical depth, horizontal depth

and sill measurements on a hypothetical cavity.

Slide 18: Figure 7. Set up of internal and external iButtons and solar shield tent

on a tree.

Slide 24: http://www.cleveland.com/neobirding/index.ssf/2010/03/post_16.html