# Presentation: 122551

## SILVICULTURE FOR SPOTTED OWLS IN DRY FORESTS:   SUPPORT FOR PLANNING  LARRY IRWIN, NCASI

**SILVICULTURE FOR SPOTTED OWLS IN DRY FORESTS:   SUPPORT FOR PLANNING**** **** ****LARRY IRWIN, NCASI**
**STEVENSVILLE, MT**

## SUMMARIZE RESEARCH INFORMATION FROM WA, OR & CA:

**SUMMARIZE RESEARCH INFORMATION FROM WA, OR & CA:**
**NEED FOR MGMT**
**WHAT THINGS MATTER TO OWLS**
**PLANNING TOOL  **

## Dry Forests in WAMore owls in At-risk Forests Class		Regime		   % (NO.)

| Class 1 | Within HRV | 20     (54) |
| --- | --- | --- |
| Class 2 | Moderately altered from HRV | 36    (100) |
| Class 3 | Significantly
Altered  | 44    (120) |

## MOST PRODUCTIVE SITES AT-RISK 

| P.Pine/fir | 26 | 10.0 | .63 |
| --- | --- | --- | --- |
| D. fir/Pine | 22 | 7.4 | .62 |
| Grand Fir | 62 | 4.6 | .54 |
| Grand Fir | 19 | 4.4 | .36 |
| Hemlock/
Subalpine | 15 | 3.0 | .14 |

| FOREST TYPE | No. 
Owl Sites | Fires/10,000
 Ac/Decade | No.yng/
year |
| --- | --- | --- | --- |

## ACTIVE MANAGEMENT NEEDED TO SUSTAIN OWL HABITAT—BUT WHAT & HOW?

**ACTIVE MANAGEMENT NEEDED TO SUSTAIN OWL HABITAT—BUT WHAT & HOW?**

## FUEL BREAKS OR REDUCTIONS COULD HAVE NEGATIVE CONSEQUENCES (E.G., FUNGAL/PREY)

**FUEL BREAKS OR REDUCTIONS COULD HAVE NEGATIVE CONSEQUENCES (E.G., FUNGAL/PREY)**

## THINNING CAN INCREASE FIRE HAZARD.

**THINNING CAN **_**INCREASE**_** FIRE HAZARD.**

## 13-YEAR WNF PROJECT, 170 OWL SITES  

**LTAs w/DEEP SOILS (site index, prey)**
**30-70% CANOPY COVER**
**BIG TREES (- EXC. @ NESTS, D-FIR) **
**~50% DRY FORESTS W/PAST P.H’s**
**5-8” TREES (-) EFFECT (BAOW)**

**13-YEAR WNF PROJECT, 170 OWL SITES  ******
_**WHAT MATTERS TO OWLS**_

**FORESTS CAN BE TOO DENSE AS WELL AS TOO OPEN  ******** THINNING OR SELECTIVE HARVESTS MAY HELP **** **

## Telemetry Studies in OR & CA> 275 owls trackedMore than 35,000 telemetry locations 9 study areas   

**TOPOGRAPHY IS AN IMPORTANT FACTOR IN SPOTTED OWL HABITAT **

## Use vs. Availability Study

- Used Inventory Data

## THINS & P.C.s DON’T CHANGE SERAL STAGE CLASS. 

- THINS & P.C.s DON’T CHANGE SERAL STAGE CLASS.
- MEASURES OF STAND DENSITY, COMPOSITION, AND SIZE-CLASS ARE REQUIRED

## STAND INVENTORY DATA  LINK W/FORESTER’S TOOLS

- STAND INVENTORY DATA  LINK W/FORESTER’S TOOLS
- (e.g., GROWTH MODELS, FIRE-RISK)

## “THE BEST JUDGE OF OWL HABITAT IS..

**“****THE BEST JUDGE OF OWL HABITAT IS..**
** ****A SPOTTED OWL”... **

## POSSIBLE Rx --500-acre analysis area (AA) 

**EMPHASIZE RMZ (productivity; vs ridges)**
**THIN FROM BELOW (but w/heterogeneity!) **
**DWD: 1 or 2 logs/acre [66’ x 2’] (or slash pile)**
**SNAGS (> 16” DBH):  ~ 2/ac (+/-)**
**40-50% AA w/150-225 sq. ft/ac (~40-70% CC)**
**< 20% AA with > 225 sq. ft/ac **
**< 20% AA with < 60 sq ft/ac (ridges)**
**REMAINDER OF AA: 60-150 sq. ft/ac**

## COMPOSITION MATTERS!

- PINE < WHITE FIR < HARDWOODS & DOUG-FIR (Mistletoe, etc.)

## MAINTAIN HARDWOODS IN UNDERSTORY 

**MAINTAIN HARDWOODS IN UNDERSTORY**** **
**MAST-PRODUCERS (?)**
**TOSS SPHERICAL DENSIOMETERS****!**

## LIMITED EXPERIENCE:  INITIAL RESPONSES TO SILVICULTURE

**LIMITED EXPERIENCE:  INITIAL RESPONSES TO SILVICULTURE**
**THAT LEFT AVE. 120 SQ. FT/AC:**
- 1.  **Owls didn’t leave **
**2.  Home range & frequent-use areas didn’t change**
**Used treated areas before & after thinning **
**Use seemed to increase along edges**

## BEYOND STANDS:  PREDICT OWL RESPONSE TO  FUEL REDUX & RE-GROWTH OVER SHORT- & LONG RUNS & LARGE SCALES

**BEYOND STANDS:  PREDICT OWL RESPONSE TO  FUEL REDUX & RE-GROWTH OVER SHORT- & LONG RUNS & LARGE SCALES**

## HABITAT ASSESSMENT & 

**HABITAT ASSESSMENT & **
** ****PLANNING TOOL TO **
**HELP INTEGRATE OWL **
**AND SILVICULTURAL**
**GOALS **

## DISCRETE-CHOICE RSF APPLIES TELEM & INVENTORY DATA w/in HOME RANGE AT  POPULATION LEVEL

## 	 QMD, TPA X SIZE CLASS, SPP. COMP. 

- 	TOPOGRAPHY (Water), ELEVATION,
- 	ROADS, NEST DISTANCE, SLOPE, ASPECT
- _VEGETATION_
- 	TPA, BASAL AREA, CANOPY COVER,
- 	 QMD, TPA X SIZE CLASS, SPP. COMP.

**FACTORS EXAMINED **

## Slide 24

## Owl Response to Fir and Hardwood Basal Area

***Owl Response to Fir and Hardwood Basal Area***

## MODEL VALIDATION

## Slide 27

## APPLICATION STEPS:  1. Map historic fire occurrence

- APPLICATION STEPS:  1. Map historic fire occurrence

## 2.  Predict pattern of fire spread

## 3. APPLY RSF TO INVENTORY IN A GIS:  RSF = EXP(DNEST+DH20+BA(FIRS)		- BA(PINE) + HDWOOD)   ESTIMATE AVERAGE (& SD) REL. PROBABILITY FOR A.A.

## COMPARE AT-RISK AREAS AND THOSE MOST LIKELY USED BY OWLS (MOVING WINDOW, MODIFY BY REPRO DATA)

**COMPARE** **AT-RISK** **AREAS AND THOSE MOST LIKELY USED BY OWLS (MOVING WINDOW, MODIFY BY REPRO DATA)**

## Slide 32

## “GROW” FOREST & RE-APPLY RSF (10-YEAR TIME-STEP?)

- “GROW” FOREST & RE-APPLY RSF (10-YEAR TIME-STEP?)

## AVERAGE REL. PROBABILITY UNDER SURFACE   ESTIMATE OF  EFFECT AT EACH STEP

- NET CHANGE IS TOTAL AREA UNDER  THE “SURFACE"

**AVERAGE REL. PROBABILITY UNDER SURFACE  ******** ESTIMATE OF  EFFECT AT EACH STEP**

## Slide 36

## SUMMARY

- MULTI-FACTORIAL PROBLEM (non-linearity)
- STRUCTURAL DETAILS MATTER (i.e., inventory)
- SPECIES COMPOSITION MATTERS (economics?)
- LOCATION MATTERS  incomplete “shifting mosaic”
- HETEROGENEITY MATTERS
- RSF MODELS  IMPROVED  ASSESSMENTS

## BAOW – NSO Interactions:

- Possible Role for Silviculture In Dry Forests?

## FUTURE:   “MANAGED” FIRE STARTS + SILVICULTURE????

## Slide 40

## A

- B

- C

## Slide 44