Post on 13-Feb-2018
transcript
Talk Outline:
• Introduction– Conceptual backgroundp g– Natural history
• Mayfly case studyMayfly case study• Implications
Population Biology: How many are there?
Nt+1 = Nt + Births - Deaths + Immigrants - Emigrants
Population Biology:Historical assumption
Nt+1 = Nt + Births - Deaths + Immigrants - Emigrants
Closed PopulationImmigration = Emigration
Metapopulation:Levins (1969, 1970)
Population of populations, connected by somePopulation of populations, connected by some degree of dispersal
Metapopulation:
Population of populations, connected by some
Levins (1969, 1970)Population of populations, connected by some
degree of dispersal.
Problem-driven Investigations: Collect data to address hypotheses about a specific species, population. “Applied” science.
Concept-driven Investigations: Collect data to address general hypotheses. Find a system amenable to question. “Basic” science.
Life Cycle of Callibaetis ferrugineus hageni:
2 weeksSubimagoImago
2 weeks
Terrestrial Habitat
1 2 3 BWP
Aquatic Habitat
50 weeks
Aquatic Habitat
Si F dit C llib ti
r2 = 0.9651800
2000e
Size-Fecundity, Callibaetis
1200
1400
1600
1800
r Fem
ale
600
800
1000
1200
Eggs
per
200
400
600
No.
E
2.0 3.0
Female Mesonotum Length (mm)
Populations of populationsPopulations of populations
ffer
ualit
y
atch
es D
ifSource-Sink
Balanced Dispersal
Patc
h Q
u P Balanced Dispersal
tions
ulat
ions
rium
ance
in P
hy P
opul
at
Met
apop
u
on-E
quili
b
Varia
All
Equ
al “Classic” Patc
hM
No
Isolated Connected
A
Degree of Exchange Among Patchesg g g
After Harrison and Taylor 1997
Talk Outline:
• Introduction– Conceptual backgroundp g– Natural history
• Mayfly case studyMayfly case study• Implications
Emerald Lake
BellviewSpatial Patterns
Friends Cut
Bellviewof Abundance:
Quigley
Rustlers
MarmotAvery
TxFsBr
Gothic
1 km
FS 401
UBBP
TxFsBrN
Pond With TroutFishless Pond
RMBL
Avalanche
UBBP
Levy
S.E
.) 3000
Trout Ponds(m
-2 +
/- S
2000
Trout PondsFishless Ponds
P <0 001
Den
sity
1000
Pfish<0.001n = 12 ponds
allib
aetis
1000
Bare FSedge F
Bare NF
Sedge NF
Ca
0
ffer
ualit
y
atch
es D
ifSource-Sink
Balanced Dispersal
Patc
h Q
u P Balanced Dispersal
tions
ulat
ions
rium
ance
in P
hy P
opul
at
Met
apop
u
on-E
quili
b
Varia
All
Equ
al “Classic” Patc
hM
No
Isolated Connected
A
Degree of Exchange Among Patchesg g g
After Harrison and Taylor 1997
-Which model best describes the Callibaetis metapopulation?
Nonselective Dispersal:Nonselective Dispersal: Source-Sink Dynamic
Source Patch, K > 1: Sink Patch, K= 0:
R i P d iRecruitment Production Recruitment Production(eggs) (eggs)
Net MigrationNet Export Net ImportNet Export Net Import
Selective DispersalSelective DispersalBalanced Dispersal Dynamic
Patch with high K Patch with low K
Recruitment Production Recruitment Production
P it
(eggs) (eggs)
Per capita exchange equal
“Balanced” Dispersal
No net import or export of eggs
J A S O N M J J A S O N
1997 1998
J A S O N- M J J A S O N
IceIce
AdultsAdults
1997-8 CohortLarvae
1998-9 CohortProduction
R iRecruitment
Microhabitat Scale: Adult Emergence Rate
7000
from the Sedge Microhabitatm
-2
5000
6000Emergence p=0.029Recruitment p=0.298n=12
Rat
ebe
r * y
r-1 *
3000
4000
5000
Num
b
2000
3000
UBBPllview
Averyanche
FS 401iends
QuigleyMarmot
stlersTxFsBr
LevyGothic
0
1000
UBBellvi Av
AvalancFS 4
FrienQuig
MarmRustl
TxFs Le Got
Pond
Emigration Index (EI):Closed Populations
EIi = Recruitmentexpected / Recruitmentobserved
where
Recruitmentexpected = Ni * Fecundityi * Mortalityadult
Emigration Index (EI):Source Sink Dynamic:
Sink = Net Importer:
Production
Source = Net Exporter:
Recruitment(Observed)
Production(Expected
Recruitment) RecruitmentProduction( )
EI > 1 EI < 1
Emigration Index (EI):Balanced Dispersal:
High K: L K
RecruitmentP d ti
High K: Low K:
RecruitmentProduction RecruitmentProduction
EI = 1EI = 1 EI 1EI 1
Emigration Index on
d-1)
200000
300000w/ Observed Adult Mortality Rate
Net Exporter ~ Source
mal
es *
Po
100000
200000p
ndex
(Fem
-100000
0
mig
ratio
n I
-200000
-100000Net Importer ~ Sink
BellviewAvery
UBBPFS 401
AvalancheLevy
GothicFriends
QuigleyTxFsBr
RustlersMarmot
Em
-300000
Pond
Patch Selection Behavior:3Patch Selection Behavior:
nsity
) p = 0.513
2
tion
Den
m-2
yr-1
) p
1
Ovi
posi
t(N
o.
0No Fish Trout
O
• Conclusions: Patterns of Abundance:• Conclusions: Patterns of Abundance:– Source-Sink Metapopulation:
L Diff i E R t• Large Differences in Emergence Rate• Local Production = Local Recruitment
E i i I d N Mi i• Emigration Index: Net Migration• Non-Selective Oviposition
• Mayfly as model system
Obj ti• Objectives:- Spatial Patterns- Patch Quality (Fish)- Dispersal- Larval Plasticity
Beaver Pond Patches:
3Pond Type: Treatment:
3
3Fishless
d i
Fishless Control
3
3
Trout Reduction
3With Trout
3
Trout Introduction
3 Trout Control
20
Trout Density by Treatment
Avalanche
12
16
20Bellview FS 401
% C
.I.)
uctio
n
0
4
8
2 +/
- 95
%
ntro
du
BeforeAdded
After *0
BeforeAdded
After *Before
AddedAfter *
Friends(#/1
00 m
16
20Levy Quigley
InFriends
Den
sity
(
8
12
16 Levy Quigley
duct
ion
Before After
Trou
t
0
4
Before After Before After
Red
Trout Density by Treatmenty ysi
ty
5 %
C.I.
)
Gothic16
20MarmotTexas Fishing
Trout Controls:
out D
ens
m2
+/- 9
5
4
8
12 Bridge
Tro
(#/1
00 m
Before After0
4
Before AfterBefore After
Local Population Growth Rate:
λ = S(l )i * S( d lt ) * Fiλ S(larvae)i S(adults) Fi
λ 1 Si kλ > 1 = Sourceλ < 1 = Sink
Terrestrial AdultStages:
S(adult)
Fi
1997-8 Cohort
Aquatic Larvae:S(larvae)i1997 8 Cohort
1998-1999 Larval Cohort
(larvae)i
1998 1999
J J A S O M J J A SSnowCover
Do Trout Reduce Patch Quality? o ou educe c Qu y?Callibaetis Population Growth Rate (λ ):
With Trout
te 4
5O
With Trout
Fishless3
row
th R
at
3
4
O
2
pula
tion
G
2O
O
Sources1
Pop
0
1 Sinks
0
Trout Density (# / 100 m2)0 1 2 3 4 5 6 7
00
Conclusions:• Patch Quality
d λ– Trout reduce λ– > 1 Trout 100 m-2 = SinkS– < 1 Trout 100 m-2 ~ Source
• Objectives:
- Spatial Patterns
- Patch Quality
- Dispersal
L l Pl i i- Larval Plasticity
15N Stable Isotope Mark-Recapture Experiment: 2 Patches
5 15NH Cl5 g 15NH3Cl
26,000
Addition Pond Unmarked Pond
300,000 250 m
(No Fish)
Ovipositing FemalesUnmarked PondAddition Pond
12P < 0.001 ed
emal
es
8
10P 0.001
Unm
arke
mbe
r of F
e
4
6
m A
dditi
on
Num
0
2 From
5 July 20 July 29 July 8 August 0
5 July 20 July 29 July 8 August
P k E P k EPeak Emergence Peak Emergence
25
Swarming Males
20
25al
es
p<0.001
ked
15
arm
ing
M
Pond U
nmar
k
10
er o
f Sw
a
Add
ition
P
5
Num
be
From
A0
Addition Pond Unmarked Pond
C l iConclusions:• Dispersal:
–Strongly Sex-BiasedStrongly Sex Biased – Consistent w/ mating system
Hi h P t h E h R t–High Patch Exchange Rate
• Objectives:j- Spatial Patterns
Patch Quality- Patch Quality- Dispersal
l- Larval Responses
“Appropriate” AntipredatorAppropriate Antipredator Traits:
• Behavior:– Reduced Activity
• Life History:– Reduced Growth Rate
– Increased Crypsis – Accelerated Development– Altered Size at Maturity
Fi ld P l ti• Field Populations:– Timing of Emergence– Size at Emergence
• Tank Experiment:– Timing of Emergence– Timing of Emergence– Size at Emergence
B h i– Behavior
D t f E f Fi ld P l ti
29 JulyE.)
Date of Emergence from Field Populations
29 July
e (+
/-1
S.
p = 0.99512 ponds
9 July
Em
erge
nce
of P
eak
E
19 June
Dat
e
High TroutLow Trout
Si t E f Fi ld P l ti3
.) Size at Emergence from Field Populations
0 659
2
+/-1
S.E
.
Males Femalespfish = 0.659psex < 0.0001
1ass
(mg
+
0
1
Dry
Ma
High TroutLow Trout0
High TroutLow Trout
D l t R t i T k
Males24 August
Females
Development Rate in Tanks
p = 0 885Males
20 August
Females pfish 0.885psex < 0.000112 tanks
16 A t16 August
12 August
Size at Emergence from Tanks
Fishless
1.7 1.9 2.1 2.3 2.5 2.7 1.7 1.9 2.1 2.3 2.5 2.7
pfish = 0.605
100 70
Trout Cues
pfish 0.605psex = 0.0004
Males
60708090
nt
Females
40
50
60
nt20304050
Cou
n
20
30
40
Cou
n~400 Eggs ~1,100 Eggs
1.7 1.9 2.1 2.3 2.5 2.7
Mesonotum Length (mm)
1020
1.7 1.9 2.1 2.3 2.5 2.7
Mesonotum Length (mm)
10
Mesonotum Length (mm) g ( )
Larval Mayfly Behavior in Tanks:
1.5
Larval Mayfly Behavior in Tanks:
30
/ Tan
k
1 0(min
-1)
ues
ues
ues
ues
LateEarlypfish = 0.584ptime < 0.001pperiod < 0.001
Development:
20
ber V
isib
le 1.0
min
g R
ate
Trou
t Cu
No
Trou
t Cu
Trou
t Cu
No
Trou
t Cu
10Num
b 0.5
Sw
imm
0 0.0
C i
• Larval Responses (Not!):
Conclusions:
• Larval Responses (Not!):– No Life History Shift
N Eff t f T t Si– No Effect of Trout on Size– No Anti-predator Behavior
I d A ti it L t i D l t• Increased Activity Late in Development
S l ti
• Why Not?
Speculation:
• Why Not?– Introduced Predator? Do non-native
trout create “ecological traps”?trout create ecological traps ?– Vulnerable to Native Trout– Strong Response in Baetisg p
– Need to test
Speculation:
• Why Not?
Speculation:
– Introduced Predator?– Lack of Trade-off?– Phylogenetic Inertia
• Ephemeral Larval Habitat• Appropriate Anti-Invertebrate Behavior
Speculation:• Why Not?
I t d d P d t ?
Speculation:
– Introduced Predator?– Lack of Trade-off?– Phylogenetic Inertia
• Ephemeral Larval HabitatA i t A ti I t b t B h i• Appropriate Anti-Invertebrate Behavior
• Dispersal from Sources to Sinks
Summary
• Source-Sink Metapopulation:• Life HistoryLife History• Dispersal / Habitat Selection
BehaviorBehavior• Larval Behavior• Predator Distribution
iffer Callibaetis mayfly population
ualit
y
Patc
hes D
iSource-Sink
ss
Patc
h Q
u P
ibriu
m
pula
tions
pula
tion
ance
in P
Non
-Equ
ili
tchy
Pop
Met
apop
Varia
Non
e “Classic”
N
PatM
Isolated Connected
N
Degree of Exchange Among Patches
After Harrison and Taylor 1997
Traditional View of Complex Life Cycles:p y(Most plants, invertebrates, amphibians, and fishes)
jReproduction & Dispersal
ProductionRecruitment
1 2 3 j-1
Growth Stages
Complex life cycles in spatially complex habitats:
1 2 3 j-1
1 2 3 j-1
Reproduction& Dispersal
Unequal Production
NonselectiveRecruitment p
jec u e
1 2 3 j 1
1 2 3 j-1
1 2 3 j-1
Growth
Source sink dynamics may be common inSource-sink dynamics may be common in groups with “constrained” dispersal:
• Social (Territorial):– Birds– Mammals– some fishes
Source sink dynamics may be common inSource-sink dynamics may be common in groups with “constrained” dispersal:
• Social (Territorial):– Birds
• “Passive” dispersal:– Plankton
– Mammals– some fishes
– Marine invertebrates– Pathogens– Plants– Agricultural Pests
Algae– Algae – Marine & FW Fishes– Aquatic insectsBold = Commercially Important Aquatic insectsBold Commercially Important
Management ImplicationsB h i d h bi li i• Behavior and habitat quality interact to determine regional population dynamicI i id if• Imperative to identify sources– Conservation Targets
P / P h / I i i (– Pests / Pathogens / Invasive species (e.g, Eurasian Water Milfoil)
• Management of “Patch Quality”• Management of Patch Quality– Trout stocking programs
“Ecological Traps”– Ecological Traps