McGrath Team Meeting

Draft Science Data Summary

Thursday Sept. 21, 2000

Presented to Team members and Presenters for comment on 10/16

 

Thursday 9/21 scheduled to be biological, social and scientific data presentations.

 

Toby  Boudreau

Only scientific census done was in 1995 & 1997 for wolf and 1996 and 1999 for moose. Additional observation/trend reviews of approximately 60 river miles south of McGrath done from 1983 to 1999.

            Census shows a decline in moose population of 28% (1924-1400)

            Observation/trend studies show decline of mean numbers of moose from 210 in 1991 to 60 in 1998 for Black River area study and 110 to 55 in Candle/Wilson study area.

            Decline of wolf population of 67% (165-56)

            No data on brown or black bear.  Observation trend indicates extremely large number of black bears as compared to other areas (observed 16 in one flight where rarely seen in other areas).  Approximately 30 black bear were taken each year.

 

Hunter reports indicate a 60+% success for all years except 1991, 1992, and 1996.  Success for 1999 was approximately 42% of all hunters.  Hunter composition shifted to primarily 19D residents in 1994.  Local hunter success has been virtually the same, with non-resident hunters being eliminated.

Hunter success appears to remain high, but requires more effort, time, travel and expense.

Toby will obtain data on level of effort over the years.

 

Wolf harvest appears to be approximately 30-35 from 1985, with peak of 42 in 1996 as result of increased local effort, with low of 3 in 1992.

 

Browse studies show felt leaf willow as most desired species.  Browse studies indicate 95% of willow browed, with 84% heavily browsed.  Willow growing taller, but still available to moose.

 

Fire history data indicates burns occurring away from river zones where hunters seek moose.  Burns require 10 years to produce browse for moose and improved browse lasts for approximately 25 years.  Most large burns occurred in 1990’s.

 

River flooding and ice scouring to regenerate browse indicate last major scouring event occurred 10 years ago.

 

Weather data as compared to calf survival showed conditions significantly hindering calf survival from 1988 thru 1996.  Snow depths exceed depths considered to hinder moose locomotion almost every year.  Periods of heavy snow coincide with periods of heated controversy on moose decline.

 

Twinning surveys reveal 20% have twins in late fall, suggesting 60% at birth.

Alternate prey discussions revealed some beaver available, but no really significant alternate food source for wolves.

Caribou does not provide alternate source to replace moose.  Nikolai residents have some access.  Influx of Mulchatna heard for two years may have brought more wolves into area and assisted wolf survival through the winter.

 

Dave Anderson Subsistence report:

 

Moose decline became a concern in 1981.  Survey of unit residents conducted shows steady decline in satisfaction of moose meeting needs.  Harvest decline from 153 in 1985 to 93 in 1995.  Harvest per capita decline from 0.2 in 1985 to 0.15 in 1995.  Per capita level of 0.2 per person considered adequate to meet needs in most of rural Alaska.  Smaller villages are more dependent on moose as less moble and fewer alternatives.

Survey of 19D residents on support for predator control shows 75% supports.  Determination of support from urban population relied upon comments to b\Board of Game.  

 

 

Mark McNay –

 

Opening statement indicated with 1400-1500 moose, a population of 50-60 wolves is about normal across the state.

 

Presented moose population modeling.

            Cautioned on use of models as showing what may happen, not what will happen.

            Model is a tool depending on quality of input data.

            Indicated black bear as significant in moose predation.  Studies show male black bear main predator on moose calves.

For 19D used moose population of 1400 and wolves at 50, with black bear taking 40% of calves, grizzly bear take 5%, and wolves at 11%

Projections show that if packs totally removed get same projection as maintaining number at 20 wolves.

 

Projections to year 2016 without any management actions show stable population at about 1300. 

If total harvest were 90 bulls and 5 cows, population remains consistent.

Change from 50 to 100 wolves does not alter population projections.

Allowing for weather did not significantly affect population.

 

Projections to year 2016 with 5 years of wolves reduced to 20 and harvest remaining at 90 showed moose population increase of 5-6% reaching maximum of 1800 in 2012 then declining as wolf population increase.  Expected to return to 1300 and again remain stable.  Suggested small increase not likely to be significant and may not be recognized by hunters.

 

Projections to year 2016 with 5 years of wolves reduced to 20 and human harvest reduced to 0 shows moose population reaching 2500 by 2012 then declining as wolf and human harvest reintroduced.  Population expected to again return to approximately 1300.

 

Projections to year 2016 with 10 years of wolf control and no reduction in hunting show peak of 2700 moose in 2015 then starting decline as wolf population increases.  Population expected to again return to approximately 1300.

 

Multiple projections to 2016 with 10 years of wolf control and no change in human harvest, but allowing for weather influence show population ranges from 1500 to 3700, with mean about 2200 in year 2016 then declining.

 

 

 

 

Projections to year 2016 with 10 years of wolf control and human harvest reduced to 0 shows moose population climbing to 3750 by year 2015.  Discussion revealed expectations for population to again return to approximately 1300 as hunting is reintroduced and wolf numbers increase.

 

Projections to year 2016 with 10 years of wolf control and black bear reduced by 30% by year 2010, with no change in human harvest of 90, shows moose population to reach 4250 by year 2016.  No projections beyond that discussed.

 

Multiple projections to 2016 with 10 years of wolf control and black bears reduced to 30% and no change in human harvest, but allowing for weather influence show population ranges from 1900 to 5750, with mean about 3000 in year 2016 then generally declining.

 

 

Predation ratio estimation based on 1500 moose show 907 calves born

            363 calves killed by black bear,

            100 calves killed by wolf

             36 calves killed by grizzly

             45 calves killed by weather

            85 adults killed by wolves

             38 adults killed by bears.

            667 mortality of moose population without weather or hunting allowances.

           

            Human harvest of 90 allows only 150 for recruitment into population.

 

Discussion of overall impacts:

            Heavy snows above critical amounts in late 80’s – mid 90’s

            Wolf numbers decline from 95-97 to amount supported by low moose numbers.

            Late 90’s high snow caused moose to concentrate on rivers, wolves followed and being near human travel corridors resulted in more observation of wolves preying on moose.

            Latest estimates and counts from 99 show wolf ratio consistent with most studies of natural dynamics in North America.

 

Vic Vanballenberge  -

 

Vic expressed that wolf control is a combination of science and public policy.   Public desires must be considered on statewide level, which drove decision of Governor Knowles.  However, whatever public program is established, it must be based on hard science to assure success and avoid further lose of public support for management actions.

 

Vic concurred with Mark that models must be taken as indicators only, subject to quality of data input to model.

 

Vic presented “Most hunters feel wolves kill moose, so if you want more moose just kill wolves”.  Many hunters present themselves as desiring to remove wolves as was done in the lower 48, which complicates striving for a middle ground with moderate number of wolves and good - NOT MAXIMUM – harvest.  To accomplish this relationship required wolf control programs to be science based.

 

Vic expressed concern with who makes decision saying the plan/action is based on sound science – are they a qualified scientist or manager responding to pressure.

Vic recommended a panel of scientists, like National Science Academy would agree current program, or any based on current data, would be week on basic components. 

 

Vic presented that in the BOG's Implementation Plan approved in Feb 2000, the moose population target is 6000-8000 by 2005 if wolf control is implemented in March 2000.  This is an example of poor science as the target is unattainable even with no moose hunting, no wolves, no bears, very mild winters, and excellent moose habitat.  The maximum rate of increase for moose populations in Alaska is 30% per year.  This would yield about 5200 moose in 2005, much lower than the plan's targets.  In reality, even if wolves were totally removed, bear predation would likely keep the rate of increase to about 5% per year thereby insuring it would be many years before significantly more moose were available to hunters. By adopting unrealistic moose population targets, the Board gives unrealistic hopes to McGrath residents and sets the stage for public backlash when wolf control fails to deliver expected results.  This is why it is very important to be sure we use sound science.

 

Vic cautioned on extrapolating data from other areas and offered recommendations on data needed.

1.      Standards of when to initiate a program, and when to end or shut off.

2.      Emphasized that before doing anything, bear predation data is needed to assure they are not enough of a problem so as to prevent achieving goal – ie. Wasting effort on wolf control. 

a.       He related to the Nelchena study of 1975 where 79% of calf kill was by bears, with 3% by wolves – when removed wolves saw no improvement, but when removed 41 bears, had a 79% increase in calf survival.

b.      Related his Denali studies that show 53% of calves taken by Bears, with 6% by wolves. Also showed that grizzlies take as many adult moose as wolves for the 21 years of his study.

 

3.      Habitat study needed to show what condition it is really in – need to look deeper than just abundance of browse, but what quality it is, when/where available and affect on calving success.  Recent belief is summer habitat is as critical as winter.

4.      Adult and calf survival, via long term collaring program, is need to verify predation rates of various sources.

 

Vic indicated it would take 3 years and substantial funding to obtain the information that is lacking on these 3 topics.  At that point, the available information would likely be sufficient to consider the implementation plan as based on sound science.

 

Vic questioned to what extent wolf control during the last 20 years contributed to the numbers of moose available to hunters in the 70’s and 89’s, and what effect low snow during those years contributed to good populations. 

 

 

Layne Adams –

 

Moose populations are healthy all over the state, and there is no reason to expect anything different in 19D East.

 

From data presented and known, can say that wolf control likely will not do much good, there are too many bears.  Bears are the problem, not wolves.

 

Overall, moose population in McGrath is in good shape, but a concern shows up in bull cow ratio.  May take several years for bull ratio to recover form today’s count of approximately 12/100.  (like to have 35-40/100 and consider it a problem when declines to 10/100 – Per Regelin)

 

Talking about moose is meaningless as issue is really bull moose available for hunting.  This makes bull cow ratios most important.

 

Boudreau’s data of 1996 indicates 1924 moose, which are 385 calves, 1270 cows and 269 bulls.  Data of 1999 shows 1404 moose, which are 380 calves, 931 cows and 95 bulls.

 

Biggest problem is sharp decrease in number of bulls – approximately 60% decline.  This could cause increase in cows not breed and/or second breeding resulting in smaller calves that are less likely to survive.

 

Lose of bulls likely due to heavy snows of recent years.  Vic indicated that 1/3 of his collared animals lost due to snow recently, with largest loss being big bulls.  Concern on loss of bulls supported by Mat-Su winter when feeding was undertaken and big bulls died in large numbers.

 

Layne disagreed with BOG finding in 1995 that productivity was low.  Population was not growing at that time.

 

Layne indicated most people do not realize the impacts of bears and blame wolves, which is wrong.

 

Layne called in a suggestion of diversionary feeding study done in small area to reduce bear predation on calves.  Estimated such an effort at McGrath would require 20 metric tons of road killed moose airlifted and distributed around calving areas during 2-3 critical weeks of bear predation.

This was successful in area 1/15 size of McGrath.

 

 

Wayne Regelin - 

 

Presented continued wolf control from 40’s thru 90 as indication that control of wolves allowed moose population to grow.   Indicated that in many years 100 wolves were taken.

 

Bears,

ADF&G know very little about bears, due to no good survey techniques. 

Poisoning of wolves in 40-50’s and trapping of bears in 60”s likely kept population low.  Low productivity rates likely showing up as large numbers observed in recent years. Observations indicate a large increase in number of bears. 

He agrees that bears likely take 40% of calves.

 

Moose,

 

First scientific study in 1996, showing population to be 1900, 1999 census showed it as 1400, 26% decline.

BOG set goal on Pete Shepard’s reporting 6-8,000 in old days, which was unsupported estimate.

ADF&G uses calculation of 7,000 square miles in GMU 19D East, estimating 3,500 miles of that area should easily be able to support 1 moose per square mile, suggesting browse could easily support 3-4,000 moose.

 

 

Wolves, Study of 1995 showed 165 wolves, while study of 1997 showed only 56, or a 67% decline.