Pheromonal and Integrated Control of the Common Carp, Cyprinus ...

Pheromonal and Integrated Control of the
Common Carp, Cyprinus carpio.
Peter Sorensen, Przemek Bajer & Haude Levesque
The University of Minnesota
psorensen@umn.edu 612-624-4997

The first fish invader
- Workshop, Minneapolis Oct 6 2006
- Postdoc needed for this project

Introduced from Caspian Sea Area,
spread worldwide

Common carp cause enormous
damage.
1. Root in the bottom for food,
uprooting native aquatic
vegetation and liberating
nutrients, destroying water
quality and waterfowl habitat
2. Can reach very high
densities (they grow quickly,
are tough, and are fecund),
displacing native fishes

Control methods Common Carp are
• Poison (rotenone)
• Physical removal
– Netting (winter)
ineffective and destructive.
• Draw-downs (reservoirs)
– Restrict spawning
– Promote winterkill
• Barriers
Unsystematic!

A New, Systematic approach is needed…
Integrated Pest Management (IPM)
Control of a species using a collection of techniques
that target specific biological attributes in
an economically, socially and ecologically viable
manner that is sustainable over the long-term.

Common Carp are the Perfect System to
Examine IPM in a Teleost
• Ecological and economic importance
• Great model
– Biology relatively very well understood
– Found in small, closed lakes

‘Integrated and pheromonal control of carps’
Legislative Commission for Minnesota Resources
2005-2009
Partnered with:
Minnesota D.N.R. (Fisheries and Ecological Services)
Invasive Animal Cooperative Research Centre (IA CRC, Australia)
Private citizens

Goals
1. Develop understanding carp spawning site
selection to determine if spawning /
recruitment might be sabotaged.
2. Develop population dynamics models to
explore and develop control options for IPM.
3. Identify and develop pheromonal attractants
for use in trapping/ removal as part of IPM:
a) Non-reproductive aggregants (LCMR)
b) Reproductive pheromones (CRC)

1. Develop an understanding of carp
a) spawning site selection, and b) recruitment

TASMANIA: an example of
Number of processed carp
550
500
450
400
350
300
250
200
150
100
50
0
spawning sabotage
‘Jonas males’ and spawning
sabotage using simple traps
Now down to a few females…
Monthly carp captures from Lake Crescent February 1995 - November 2003
Total of 7753 carp removed and processed. Population estimat
than 20 females remain

1a. Spawning habitat choice in Minnesota
Methods:
1. Identify representative study lakes
2. Radio-track male and female carp to determine spawning sites.
3. Measure physical variables that characterize spawning sites
Przemek Bajer

X
Year 1
Study 3 lakes & radio-tagged fish
Transmitters implanted 4/12/06 –
4/25/06; N=49

Fish distribution
5/07
5/10-18 – spawning in the Marsh

5/30-6/20 – spawning in Susan
5/26-7/3 spawning in Riley
Fish distribution
5/25-6/13

Spawning sites location and number:
little correlation between spawning & adult abundance
8 site-days
- Most adults?-
256 site-days
26 site-days
256 site-days
- Fewest adults?-

Rice Mars h
0
5
10
15
20
25
30
35
4/17
4/24
5/1
5/8
5/15
5/22
5/29
6/5
6/12
6/19
6/26
7/3 0
10
20
30
40
50
60
Susan
0
5
10
15
20
25
30
4/17
4/24
5/1
5/8
5/15
5/22
5/29
6/5
6/12
6/19
6/26
7/3
0
10
20
30
40
50
60
Surface temperature (C)
No. spawning sites
Riley
5
10
15
20
25
30
4/17
4/24
5/1
5/8
5/15
5/22
5/29
6/5
6/12
6/19
6/26
7/3
0
10
20
30
40
50
60
Spawning activity

Spawning - Results
• Carp spawn a great deal and while they show
preferences, they do not appear to be
something we can manipulate
• Temperature is a permissive factor
• Spawning activity occurs in short, synchronized
bursts - Priming pheromones (17,20βP -A tool?)
• Adult carp move actively between lakes and
may home but this does not appear of special
importance. Adult barriers not useful.

1b. Recruitment: when/how?
Methods
1. Check egg viability in lab
- Hatch in aquaria
2. Survey young in lakes:
Trap nets -- 44 trap-net-nights
Littoral seines – 15 samples
Electro-fishing – 1h in each lake

Results
- Egg survival high to hatching (>50%)
- Yet, very few YOY!
Lakes Susan: 0
Rice Lake Marsh: 0
Lake Riley: 9 YOY (3/ha) by seining
vs. 10,000 YOY of other species!
- Recruitment is not a simple function of spawning activity

2. Carp population dynamics modeling
for understanding and control

1400
1200
1000
800
600
400
200
1400
1200
1000
0
800
600
400
200
0
Why modeling?
ex. ‘Carpsim Model’
Number Adults
New Recruits
1990 2000 2010 2020 2030 2040 2050
Number Adults
New Recruits
1990 2000 2010 2020 2030 2040 2050
Non-selective,
routine
removal of
10% of adults
‘Removal’ of 10%
of females using Daughterless
Paul Brown

Our model will:
- use parameters developed for carp in the Midwest
- be loosely based on CarpSim (also deployed)
- allow for seasonal fluctuations of parameters
- incorporate stochastic environmental effects
(winterkill, etc.)
- allow for modeling carp population responses to a
variety of local management control strategies
- use SAS.

X
4 Lakes selected.
Echo
Dog
Eide
Dutch

Seining, marking, sampling carp (ongoing)

Tentative Results
Many year classes appear to be missing,
suggesting ‘something’ can/does control
carp numbers

3. PHEROMONES
‘innately recognized chemical signals that pass
between organisms of the same species and are
detected by the sense of smell.’

The sea lamprey migratory pheromone
Niagara Falls, 1 lb, 1 month
Sorensen et al. 2005
Nature Chemical
Biology 1: 655-

Quick lesson on teleost pheromones
• Important and potent
• Comprised of body metabolites
• Derived from common hormones and
conserved between genera
• Typically mixtures, which likely identifies
species

Pheromonal odorants in Goldfish
1 Recrudescent pheromone
pheromone
2. Preovulatory Pheromone 3. Ovulatory pheromone Male
HO
?
H
O
17β-Estradiol
O
O
O
O
O
ßOH
O
S O
Source: Ovary/kidney Ovary/kidney Oviduct Testes
OH
OH
17,20β-dihydroxy-4-pregene-dione-20-sulfate
(17,20β−P-S)
O
Androstenedione (AD)
17,20β-dihydroxy-4-pregene-dione
(17,20β−P)
COOH
Prostaglandin F2α (PGF2α)
15Keto- Prostaglandin F2α
(15K-PGF2α)
O
O
Androstenedione (AD)
Function: Male arousal Arousal/sperm production Female identification Aggression
OH
OH OH
OH
OH O
COOH

Goldfish AND Common Carp
Very closely related, Hybridize
Identical physiologies:
-sex hormones
-chemosensory systems
Identical behaviors
OH
OH O
COOH
1 gram in 10,000 Olympic swimming pools

Aggregation Pheromones
Chemical cues that cause conspecifics of all
maturities to form groups (Wyatt, 2003)

Difference in Time Spent on Treatment Side
120
100
80
60
40
20
0
-20
*
120
100
80
60
40
20
0
-20
Goldfish
*
Food
Goldfish
Common Carp
Fathead Minnow
White Sucker
Catfish
Northern Pike
Yellow Perch
Water

Difference in Time Spent on Treatment Side
A Carp Aggregation Pheromone
120
100
80
60
40
20
0
-20
*
Y Data
120
100
80
60
40
20
0
-20
*
*
(Sisler et al., 2005)
Food
Common Carp 1
Common Carp 2
Goldfish
Fathead Minnow
Yellow Perch
Control

Purification and isolation of attractants
for females
Haude Levesque

Relative attraction (%)
60
50
40
30
20
10
0
N=10
Are mature female Goldfish
attracted to conspecific odor?
Water
control
*
Immature
goldfish odor
*
Food
odor
60
50
40
30
20
10
0
*
Mature male
goldfish odor
*
Food
odor
60
50
40
30
20
10
0
Differences in
mature male
and immature
goldfish odor
*
Food
odor

Are Sexually receptive female goldfish
attracted to males and immature fish?
Relative attraction (%)
N=6
40
30
20
10
0
Water
control
Immature
goldfish odor
*
Male goldfish
odor
*
Food
odor

Are mature female carp
attracted to immature carp?
Relative attraction (%)
N=12
40
30
20
10
0
*
Water control Immature
carp odor
*
Food odor

Results
• Common carp and goldfish both employ speciesspecific
aggregation pheromones that attract
strongly. They are NOT known bile acids.
• Goldfish (and likely carp) also employ a male
pheromone that attracts sexually receptive females.
• These pheromones are likely comprised of mixtures
of a few metabolic products.
• These cues have potential for use in control.

General Conclusions/ Directions
Pheromonally-assisted trapping/ sabotage,
combined with commercial seining,
predator introduction, barriers has promise
in an IPM management scheme

Acknowledgements
Legislative Commission for Minnesota
Resources
Minnesota DNR
IA CRC

Common Carp Workshop!
Oct 6 2006, Minneapolis

Male Sex pheromone
Poling et al. 2001

We are now collecting:
-Densities of 4 carp populations in MN lakes
-Age-structures of populations
-Age-weight relationships
-Age-specific survival rates
-Age at maturity
-Weight-fecundity relationships
-Stock-recruitment relationships

Number of Weed Inspections
110
100
90
80
70
60
50
40
30
20
10
0
Control Weed
Pheromone Weed
**
Control Period Experimental Period

Importance of Pheromones to Male Goldfish
% Time Courting
100
50
0
Sham
One Nose
Blocked
Stacey & Kyle (1983)
*
Both Noses
Blocked

Postdoc needed!
• Characterization and identification of male
pheromone.

General Conclusions
Spawning sabotage may be possible but key
likely is recruitment.

QUESTIONS?

I - Pretest
II - Test
Well water
Methods
OR
Well water
Well water Fish odor Well water Well water
III – Food control
Food odor
Well water
•Fish position is recorded every 15 sec for 15 min
•Test odor and food odor are added in the side the less used by the fish

The Goldfish/carp hormonal sex pheromone system
FEMALE
MALE
LH
E2
VITELLOGENESIS
E2 E2
?
Recrudecsent
pheromone
T
T
+
AD
LH
LH
AD 17,20ß-P PGF2α
17,20ß-P
AD
17,20ß-P
Release to the Water
Attraction to female LH
OOCYTE MATURATION
Preovulatory
pheromone
17,20ß-P
PGF2α
17,20ß-P-S
Sperm
Postovulatory
pheromone
15K-
PGF2α
PGF2α
Female spawning
behavior
Spawning
synchrony
Male spawning
behavior
1200 2000 0400 1200
Time of day

Fish commonly employ pheromones to
find their way around large
dimensionless environments
O
OH
OH OH
O
O Gl
OH
OH

Adult Immigration
Departures?
New Arrivals?
Number of yearlings
2. Population Dynamics
Food supply
Predation
Total number of
Adults in a Lake
Disease
Disease
Food supply WINTER
Number of larvae
Adult Emigration
Temperature
Substrate
Number of eggs fertilized
Disease
Predation Predation

IPM requires you to ‘Know your enemy’
We do NOT know:
1) What determines carp reproductive success.
2) How fast carp grow and why.
3) Where young carp go, and how/ what determines survival?
4) Where adult carp move and why?
5) How old carp get and why?

Mortality
Major processes in the population
F3 F4 F5 Fn 0 1 2 3 4 5 …………………. n
S0,1 S1,2 S5,6 S6,7 S7,8 S5,n Age
Weight
Age
Fecundity
Weight

Methods
• Select 4 lakes with moderate-high carp densities
• Mark and recapture fish to estimate populations
• Repeat estimates in 2007 to:
- obtain survival rates
– Age sub-samples to determine age-structures and
annual growth rates
– Estimate recruitment dynamics

• Picture of Przemek

% Time Courting
100
50
0
Sex Attractants:
Importance of Pheromones to Male Goldfish
Sham
One Nose
Blocked
Stacey & Kyle (1983)
*
Both Noses
Blocked
Not tested yet in Carp

THE GOLDFISH
- Scramble spawner
- Live in turbid environment,
- Seasonal
lack sexual dimorphisms
- External fertilizer
- Gametes viable short time
-‘Only vertebrate species for which
production and release of the cue, olfactory
basis of responsiveness, and biological
responsiveness are clearly established.’
Importance of Pheromones to Male Goldfish
100
Stacey & Kyle (1983)
% Time
Courting
5
0
0
*
Sham One Nose Both
BlockedNoses
Block
ed

Fecundity (ovaries) and age (otoliths)