Skip this Video
Download Presentation
フィードバック管理 と資源評価

Loading in 2 Seconds...

play fullscreen
1 / 21

Feedback Management - PowerPoint PPT Presentation

  • Uploaded on

フィードバック管理 と資源評価. 松石隆先生、菅野泰治先生、西村欣也先生はじめ北大の皆様に感謝. Feedback Management. Uncertainty in stock assessment Accountability Dynamic change in abundance Adaptability (tuning catch effort) Successive Monitoring!!!. Revised Management Procedure (RMP) in IWC.

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
Download Presentation

PowerPoint Slideshow about 'Feedback Management' - Roberta

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript


feedback management
Feedback Management
  • Uncertainty in stock assessment
    • Accountability
  • Dynamic change in abundance
    • Adaptability (tuning catch effort)
  • Successive Monitoring!!!
revised management procedure rmp in iwc
Revised Management Procedure (RMP) in IWC
  • Moratorium of commercial whaling since 1982 (until RMP?)
  • RMP was adopted in 1994, but has not yet enforced.
feedback management for sika deer in hokkaido japan
Feedback Management for Sika deer in Hokkaido, Japan


density dependent hunting pressure adaptability
Density-dependent hunting pressure (adaptability)

%P>50%: Emergent Decrease (<4 years)

25% < %P : Gradual Decrease

5% < %P : Gradual Increase

%P <5% or after the severe winter: Ban-on-Hunting

Hokkaido, tested land

stage structured model
Stage-Structured Model

sika deer has little densityeffect and I ignored

Nc, Nf, Nm: No. of calves(0.5), females & males(≧1.5)

Lfc(t)= Lmc(t)= exp[-Q(t)Hc(t)]exp[-Mc(t)]exp[-Rc(t+1)],

Lff(t) = exp[-Q(t)Hf(t)]exp[-Mf(t)]exp[-Rf(t+1)] ,

Lmm(t) = exp[-Q(t)Hm(t)]exp[-Mm(t)]exp[-Rm(t+1)] ,

Hokkaido, tested land

risk management
Risk Management

We set the upper and lower limit (%P- & %P+) of population size P such that, within the next 1 century,

Prob{P<1000 individuals} < 1%

Prob{%P<%P- or %P> %P+} < 5%.

Therefore, %P- 5%, %P+ 50%

Hokkaido, tested land


population indices
Population Indices
  • Catch & Watch per hunter day
  • Spotlight census
  • Helicopter census
  • Train accidents
  • Damage of agriculture & forestry
    • Uncertainty of absolute size

Hokkaido, tested land


population index by spotlight census for eastern hokkaido
Population index by spotlight census for eastern Hokkaido

Population estimationhas large uncertainty

Hokkaido, tested land

fallacy of 120 000 deer hypothesis
Fallacy of 120 000 deer hypothesis
  • >30000 deer were killed every year since 1995
  • Male deer is still abundant
  • Natural growth rate is 15-20%
  • Population began to decrease?
  • 160-240 thousand deer in 1993

Hokkaido, tested land

rmp for south pacific minke whale
RMP for south Pacific minke whale
  • Pt+1-Pt = r[1-(Pt /K)z]Pt-Ct
    • think uncertainty in r, K, Pt /K and Pt (relative and absolute P)
    • no age structure
    • ignore uncertainty in z (density-effect)
iwc sc concensus
IWC/SC concensus
  • 2000 minke whale is commercially exploitable.
  • Catch Limit is determined by

Lt=2.12r (Pt /K-0.54)Pt

  • Scientific whaling catches now 400!
recent iwc sower census data suggests
Recent IWC (SOWER) census data suggests
  • Minke whale population is 30%-70% as was in ca1990.
  • Anti-whaling NGO may think “Whaling is over”.
  • Japan Gov’t may think “this census is uncertain…”
why do minke whale decrease
Why do minke whale decrease?
  • Artifact in monitoring
  • Ecosystem change
    • Short resource (krill)
    • Competition with other whales
  • Super-Compensation
artifact hypothesis
“Artifact Hypothesis”
  • RMP is realizable only under effective monitoring;
  • Scientific whaling does not satisfy RMP.
  • Precautionary approach.

Commercial whaling isCritically Endangered

competition hypothesis
Competition hypothesis
  • Competition decreases
    • Recruitment or fecundity?
    • Adult mortality?
  • Why did the minke whale increase in the 1980s?
super compensation
  • Demographic Momentumdue to drastic change in catch effort from the 1970 to 1990,
  • Age structure changed greatly.
  • Same phenomenon as southern bluefin tuna
demographic momentum by a leslie type model
Demographic Momentum by a Leslie type Model
  • Age at maturity = 11years
  • Moratorium in t=0
  • RMP begin in t=30
  • Tune recruitment,>Tune total stock.
  • Monitor age structure!!!
  • Scientific Whaling is useful
  • Feedback management should investigate stock size and age structure.
  • Temporal decrease of minke whale may be explained by demographic momentum.