GEOGRAPHIC VARIATION IN NORTH PACIFIC HERRING POPULATIONS: PAN-PACIFIC COMPARISONS AND IMPLICATIONS FOR CLIMATE CHANGE IMPACTS Reporter : 曾建豪 D.E. Hay, K.A. Rose, J. Schweigert, B.A. Megrey Progress in Oceanography 77 (2008) 233–240

Biological characteristic Depth : < 200m Latitude : 35 °N ~ 70 °N Spawn season : spring Hatch : 2~3 weeks Mature : South  2 years North  3-5 years

Introduction fundamental properties geographic variation size-at-age spawning time duration of the spawning period recruitment population diversity climate fluctuations

Methods and materials- Size-at-age and fecundity data Sources: 1. Wakefield herring symposium in PICES/GLOBEC symposium Asymptotic weight Length at age Fecundity data Recruitment data population diversity

Asymptotic weight mean age-specific weight (g) age-specific increments (ASI) of weight (g) linear regression

Length at age Age 5, 11populations Age 2-14, 7populations

Data

western Pacific eastern Pacific

Fecundity data fecundity (eggs/g) = dividing the total egg counts (eggs) whole body weight of spawning females (g)

Fecundity data Gulf of Alaska British Columbia California

Recruitment data British Columbia, Alaska, Bering Sea coefficient of variation of annual recruitment (CVR = mean/SD)

CVR British Columbia, age 5 Alaska, age 5

CVR Bering Sea, age 4

Herring population diversity distinct populations populations per unit of coastline (1000km) complexity of the coastline Arcview Spatial Analysis

Data analyses Latitude (length) East-West (weight) ANOVA Mann Whitney test

Results Geographic variation- Asymptotic weight western Pacific eastern Pacific Mann-Whitney test

Length at age ANOVA northernsouthern

Length at age western Pacific eastern Pacific

northern regions < 0.4 populations/1000km > 4 populations/1000km population diversity Population diversity Washington State and British Columbia Bering Sea California

Area-specific recruitment highest CVRs, greatest range of variability CVR = latitude

Discussion- Increase in size with latitude individuals smaller lower longevity higher relative fecundity 150 eggs/g, Gulf of Alaska 200 eggs/g, British Columbia 220 eggs/g, California

East–West differences in growth and asymptotic weight western Pacific eastern Pacific nutrients continental shelf area gene

Population diversity Sea of Okhotsk Yellow Sea

Recruitment variation versus spawning duration early, long late, short zooplankton abundance

Recruitment variation versus spawning duration high frequency of strong year classes war period (1939–1945)

Climate change impacts sardine (Sardinops sagax), anchovy (Engraulis mordax) smaller, non-migratory

Climate change impacts San Diego Santa Barbara

Thanks for your attention !