Breeding Dynamics to Maternal Effects:Breeding Dynamics to Maternal Effects: the shape of populations to comethe shape of populations to come

Ian A. FlemingIan A. FlemingOcean Sciences CentreOcean Sciences Centre

Memorial University of NewfoundlandMemorial University of Newfoundland

Describe an animal’s mating behavior and parental care

Breeding SystemsBreeding Systems

Males

Potential Rate ofPotential Rate ofReproductionReproduction

Females

HIGH LOW

OSR male-biased

Aggregation of resources & mates Sex ratios

Environment

expensive gametes, and/or care

weak mating competition

high mate choice

cheap gametes, shareable care

or no care

intense mating competition

low mate choice

General Framework for Sexual SelectionGeneral Framework for Sexual Selection

Generates Intense Selection &Generates Intense Selection &Shapes the Dynamics of PopulationsShapes the Dynamics of Populations

Experimental DesignExperimental Design

No Competition

High Density

Medium Density

Low Density

Gravel Covered

Gravel Covered

25 m

4 m

Fleming & Gross 1994

Opportunity for SelectionOpportunity for SelectionNo Competition Competition

Female 0.025 0.146

Male 0.025 1.298

What does this individual variation mean?

Variance in Salmon Spawning Variance in Salmon Spawning SuccessSuccess

♀ = 70% (53-88) = 70% (53-88)

♂ = 116% (59-160)= 116% (59-160)(Fleming & Gross ‘94, Fleming et al. ‘97, Garant et al. 01, (Fleming & Gross ‘94, Fleming et al. ‘97, Garant et al. 01,

Dannewitz et al. ‘04)Dannewitz et al. ‘04)

Intense SelectionIntense Selection

Traits under SelectionTraits under SelectionFemales

Body Size = 0.18 + .03 ***

Caudual Peduncle = 0.11 + .04 *

Males

Body Size = 1.10 + .15 ***

Hooked Snout = 0.47 + .20 *

Fleming & Gross 1994

Evolution of Specialized Evolution of Specialized Breeding Traits & BehavioursBreeding Traits & Behaviours

Density & Male SuccessDensity & Male Success

Somatic Weight (kg)1 2 3 4 5 6

Est

imat

ed F

erti

lizat

ion

Su

cces

s (x

100

0)

0

2

4

6

8

10

12

14

Low

High

Medium

Evolution ofAlternative

ReproductiveTactics

Number of Parr / Spawning

0 1 2 3 4 5 6 7 8 9

Fre

qu

ency

0

10

20

30

40

50

60

Nu

mb

er

of

Sp

aw

nin

gs

Early Male MaturityEarly Male Maturity Atlantic SalmonAtlantic Salmon

• Fertilize 11-65% of eggs

• Affect genetic structure

( Garant, Fleming, Einum & Bernatchez 2003 Ecol Lett; Weir, Hutchings, Fleming & Einum 2005 CJFAS)

Anadromous

ResidentMature Parr

Oncoryhnchus mykiss

Salmon breeding systemSalmon breeding system

• Shaped byShaped byCompetition for matesCompetition for mates

• Shaping Shaping Trait & Life history evolutionTrait & Life history evolutionGenetic StructureGenetic Structure

• Female roleFemale role?? Competition for breeding resourcesCompetition for breeding resources

Female Breeding Female Breeding SuccessSuccess

• Success more than fecundity, much moreSuccess more than fecundity, much more ......

0 1 432 5 6

Somatic Weight (kg)

0 0

1 2

2

3

4

4

5

6

10

8

Su

rviv

ing

Eg

gs

(x 1

,000

)

Fe

cun

dit

y (

x 1

,00

0)

Fecundity

Surviving eggs

Fleming ’98

Maternal EffectsMaternal EffectsShaping of Offspring PerformanceShaping of Offspring Performance

(e.g.,Einum & Fleming 2000 Nature; Einum, Hendry & Fleming 2003 Proc R Soc Lond F; Einum & Fleming 2004 Evol Ecol Res)

1. Maternal investment – size of egg

2. Breeding Time

3. Nesting location

Egg SizeEgg SizeWhat Does a Female Do?What Does a Female Do?

Ovary

FewLarge

ManySmall

Female reared to adulthood in captivity

Eggs

Fertilized by one male

LargeSmall

Experimental DesignExperimental Design

Test across a range of environmental qualities

Habitat Quality Index

Gro

wth

In

dex

Large EggsLarge Eggs

Small EggsSmall Eggs

Egg SizeEgg Size

slopes: slopes: P P < .001< .001

Einum & Fleming 1999 Proc R Soc Lond B

Fertilized by one male

Breeding TimeBreeding TimeFemaleFemale

Eggs

EarlyEarly Late Late

10-12 day range

’ ± SE P

Mortality 0.391 ± 0.138 0.016

r2 P

Body size 0.61 0.001

Selection Selection 17 & 44 days postemergence

Einum & Fleming 2000 Evolution

Nesting LocationNesting Locatione.g., Conventional vs. Effective Densitye.g., Conventional vs. Effective Density

Conclusion: breeding systemConclusion: breeding system• Shaped byShaped by

Reproductive allocationReproductive allocation Competition for matesCompetition for mates Competition for breeding resourcesCompetition for breeding resources

• Shaping Shaping Trait & Life history evolutionTrait & Life history evolutionGenetic Structure Genetic Structure Offspring PerformanceOffspring Performance

• Setting the stage for Population Setting the stage for Population dynamicsdynamics

Informing Conservation managementInforming Conservation management

• Response of populations to depressions Response of populations to depressions in size (natural and human induced)in size (natural and human induced)

• Intentional & unintentional Intentional & unintentional release of cultured fishrelease of cultured fish

AcknowledgementsAcknowledgements: Sigrud Einum, Mart Gross, Kjetil : Sigrud Einum, Mart Gross, Kjetil Hindar, Bror Jonsson, Anders Lamberg.Hindar, Bror Jonsson, Anders Lamberg.

SupportSupport: Norwegian Research Council, Natural Science : Norwegian Research Council, Natural Science and Engineering Council of Canada, European and Engineering Council of Canada, European Commission Grant ProgrammeCommission Grant Programme