Post on 21-Jan-2016
description
Reporting Issues and Trends of Alaska Moose Hunters
Jen Schmidt
Post Doc, Institute of Arctic Biology, UAF
Contact: fsjis@uaf.edu
Under Reporting by Moose Hunters: Background• Previously researched by Andersen and Alexander 1992 in interior
Alaska
• Ours differs in that we:– Expanded the focus to Statewide– Added some new parameters– More of a statistical approach
• Two measures of reported harvest– Subsistence household surveys conducted by members of the
community through the division of Subsistence at the Alaska Department of Fish and Game (ADF&G)
– Harvest tickets that are returned to division of Wildlife Conservation at ADF&G
• Measure of under reporting– Ratio = Subsistence Household Surveys
Hunter Harvest Tickets
Under Reporting by Moose Hunters: Limitations
• The “year” does not match up between the two databases– Subsistence (January-December)– Hunter Harvest Tickets (July-June)– Since most moose are harvested in the fall this minimizes this
issue since fall is in the same “year” for the two databases
• In large communities not all households can be surveyed so survey information must be extrapolated to represent the whole community
n = 118n = 97
Under Reporting by Moose Hunters: Model & Parameters
• General linear model
• Parameters (* used by Andersen and Alexander 1992) – Percent of a community that:
• Attempts to harvest a moose*
• Harvests a moose*
• Receives meat or other parts of a moose*
• Shares/Gives meat or other parts of a moose*
• Is Native*
– Population Size*– Median Household Income*– Presence of an Area Biologist employed by ADF&G*– Distance (Km) from a community with an Area Biologist– Presence of a license vendor
Model Results
Parameter * Co -Efficient
P-value
Intercept 0.86 0.919
% hunt a moose -0.16 0.161
% harvest a moose 0.54 0.008
% use a moose -0.46 0.023
% receive a moose 0.40 0.025
% give a moose 0.11 0.474
% Native 0.01 0.901
Distance to area biologist 0.03 0.125
Population size +0.00 0.600
Median household income -0.00 0.731
Presence of an area biologist
Yes N/A N/A
No 3.21 0.535
Presence of a license vendor
Yes N/A N/A
No -1.69 0.640
Parameter* Co-Efficient
P-value
Intercept 2.28 0.488
Harvest 0.42 0.002
Use -0.45 0.013
Receive 0.44 0.006
*Percent of a community
Positive value indicates increase in under-reporting
Full Model P- value = 0.02 Reduced Model P-value = 0.002
Strong Sharing Network
Use moose meat or other parts
Attempt to harvest Harvest a moose Give moose meat or other parts
Attempt to harvest 0.75 Pearson Correlation
<0.0001 P-value
Harvest a moose 0.75 0.80
<0.0001 <0.0001
Give moose meat or other parts
0.81 0.62 0.76
<0.0001 <0.0001 <0.0001
Receive moose meat or other parts
0.89 0.51 0.46 0.70
<0.0001 <0.0001 <0.0001 <0.0001
Results: t-tests
Less Under-Reporting More Under-Reporting
n = 13 n = 84
Parameter Mean Standard Error
Mean Standard Error
P- value
% hunt 31.95 6.62 45.77 2.22 0.029
% harvest 11.58 3.43 27.91 1.89 0.002
% use 44.26 7.98 67.51 2.53 0.002
% receive 38.17 7.22 50.93 2.16 0.041
% give 13.28 3.03 27.39 1.71 0.002
% Native 31.85 7.63 74.30 3.22 <0.001
Population size* 1,032 506 563 110 0.382
Distance to area biologist 87.16 18.35 113.14 8.65 0.265
Median household income
37,587 3,886 32,590 1,343 0.185
* Indicates unequal variances
Under Reporting by Moose Hunters: Conclusions
• The simplest model that explains under reporting contains the percent of the community that:– harvests a moose– uses meat or any part of a moose– receives meat or any part of a moose
• Smaller and more rural communities appear to have more under reporting, but if small amounts of under reporting by large cities can amount to large under reporting
Under Reporting by Moose Hunters: Future
• Explore if reporting rates differ in areas that have or had co-management programs or working groups
• Better understand why the results from the two methods used differ for the percent of the community that hunts moose and uses moose meat or parts
Statewide Trends in Moose Hunting
Background
• Data used was the hunter harvest tags returned by moose hunters to the Alaska Department of Fish and Game (ADF&G) regardless of success
• Statewide analysis
• Dates range from 1990 to 2006
Number of Moose Hunter, Harvest, and Success
0
5000
10000
15000
20000
25000
30000
35000
1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006
0%
5%
10%
15%
20%
25%
30%
Hunted
Killed
Success
Success by Transportation Type for Moose Hunters in Alaska from 2003 to 2006
0%
10%
20%
30%
40%
50%
60%
Airpla
ne
Horse
/Dog
Tea
mBoa
t
3 or
4 W
heel
er
Snowm
achi
neO
RV
Highw
ay
Airboa
t
% Success
% Use
n = 111,985p < 0.001
n = 111,985p < 0.001
In the legend the change in 3 or 4 wheeler use decreases from left to right
Top 10 GMUs with Biggest Change in 3 or 4 Wheeler Usage from 1990 to 2006
0
100
200
300
400
500
600
700
800
900
1000
1100
1200
1300
1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006
14A 20B 20A 13A 15C 13E 20D 20E 16A 13B
Average Distance by Success for Moose Hunters
0
15
30
45
60
75
90
105
120
135
150
165
180
195
1987 1992 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006
Av
era
ge
Dis
tan
ce
(K
M)
Successful
Unsuccessful
Average Distance (KM) to Harvest a Moose
0
100
200
300400
500
600
700
800
Dis
tanc
e (K
M)
1990-06 Average
2006
72753
3
93
5442
713 9103
25
470
28
Numbers above bars represent number of hunters who were successful in 2006
Conclusions
• Management decisions at the local level can be observed at the Statewide level
• Location and presence of moose influence how far hunters travel
• There is a lot of spatial variability, however certain trends can be observed such as:– Increase of 3 or 4 wheelers and airboats– Relatively content number of moose hunters, harvest
level, and overall success
Thanks to EPSCoR for there support
Also thanks to the Alaska Department of Fish and Game for the use of their data and
feedback.
Jen SchmidtContact: fsjis@uaf.edu
Examples of moose-habitat rules• Direct climate effects on moose
– Moose void deep snow (>2.3 ft) because it increases death of moose– Warm conditions are stressful for moose
• Winter >23°F (-5°C); Summer 57°F (14°C)
• Indirect climate effects: More wildfire– Moose prefer recent burns (11-25 years)– Moose prefer burn edges and unburned patches within a burn– Moose move into burns if moose density high – Moose move into burns if unburned habitat is poor for moose and/or
limits the number of moose• Changes in vegetation
– Moose prefer deciduous over spruce or tundra, so changes of spruce or tundra to deciduous will increase moose habitat
• Hunter behavior– Moose hunting is concentrated near roads and rivers– Weather (e.g., warm fall, early snow) influences harvest success– Increased temperature in fall can lead to spoilage of moose meat– Influence of gas price/employment on harvest level