A Geographical Evaluation of Nesting Substrate for the Puaiohi,

Myadestes palmeri

Ruby Hammond1, Lisa Crampton1, Pauline Roberts1,2

1Kaua‘i Forest Bird Recovery Project, Hanapepe, HI 2Sapphos Environmental, Inc., Pasadena, CA

Puaiohi

• Population estimate

- 800 individuals

• Habitat Preference

- Streams

• Nest Substrate

- Cliff walls along

streams

Photo credit-Robby Kohley

Halepa‘akai Study Area

Natural Preferences???

Puaiohi Nest Wall Puaiohi Nest

Methods:

• Nests - located from 2007-2009

• 8178m total nest wall length (n=132*)

-Used vs. unused

-Number times used

-In Territory vs. Outside

• Surface cover

• Shrub cover

• Tilt degree

• Stream distance

• Nestwall height

• Cliffwall height

Results-Used vs. Unused

• 38% used

• Mean nest height = 4.9 ± 2.8 m (N = 78)

Χ2 = 3.9, n=132, p=0.049

0

2

4

6

8

10

Me

an N

est

wal

l H

eig

ht

(m)

Mean Nestwall Height for Used vs. Unused Walls

Used

Unused

Models for Walls Used vs. Unused AICc Δ AICc Weight

Nestwall height 174.7 0 0.612

Tilt 177.3 2.56 0.171

Nestwall height, shrub class 178.7 3.61 0.101

Shrub class 179.8 4.88 0.054

Stream distance, shrub class 181.5 6.42 0.025

Nestwall height, surface class 182.1 6.85 0.020

Surface class 183.4 8.32 0.010

Surface class, tilt degree 184.5 9.21 0.006

Nestwall height, surface class, shrub class, strea surface distance, tilt degree 187.9 11.08 0.002

Χ2 = 3.9, n=132, p=0.049, SE = -0.13 ± 0.07

Results-Number of Times Used

0

1

2

3

4

5

6

7

8

9

0 5 10 15 20 25

# Ti

me

s W

all U

sed

Nestwall Height (m)

Number Times Used vs. Nestwall Height

F 1,48 = 6.48, p=0.014

Results-Number of Times Used

Model of # Nests for Used Walls AICc Δ AICc Weight

Nestwall height, shrub class 164.7 0 0.42

Nestwall height, surface class 165.3 0.6 0.311

Nestwall height, surface class, shrub class, tilt degree, stream distance 167.4 2.7 0.109

Surface class 168.4 3.7 0.066

Shrub class 168.4 3.7 0.066

Nestwall height 170.4 5.7 0.024

Stream distance 175.6 10.9 0.002

Tilt degree 176.8 12.1 0.001

Results-Walls In and Out of Territories

0

5

10

15

20

Clif

fwal

l He

igh

t (m

)

Cliffwall Height Inside Territory vs. Outside Territory

Inside Territory

Outside Territory

X2 = 2.60, N=126, p = 0.11, b= -0.09 ± 0.06

Models of Walls in Territories vs. Outside AICc Δ AICc Weight Cliff height 96.9 0 0.351

Stream distance 98.3 1.45 0.170

Cliff height, surface class 98.9 2.06 0.125

Cliff height, shrub class 99.7 2.78 0.087

Tilt degree 99.9 3.04 0.077

Cliff height, tilt degree 100.1 3.23 0.070

Cliff height, tilt degree, surface class 101.2 4.34 0.040

Shrub class 101.4 4.49 0.037

Cliff height, shrub class, tilt degree 101.9 5.02 0.029

Cliff height, surface class, tilt degree, stream surface 103.5 6.61 0.013

Conclusion • Used nestwalls taller than unused

• Increase in use = increase in nestwall height

• Taller cliffwall inside territories

Photo credit- Lucas Behnke

The Future

• Wall data

• Occupancy surveys

• Fruit and vegetation surveys

• Telemetry

• Combine efforts

Photo credit-Lucas Behnke

Thank You!

• Field Biologists!!!

• State of Hawaii, Division of Forestry and Wildlife

• U.S. Fish and Wildlife Service

• U.S. Geological Survey

• Pacific Cooperative Studies Unit