updated seminar
TRANSCRIPT
1
Invasive plants and Native anurans
A tale of two interactions
2
3
Amphibian declines
• ~6000 spp.• ~1/3 threatened• ~160 presumed
extinct recent times
4Habitat loss/degradation
Why?
5
Loss vs. Degradation
6
Invasive plants
• 4,000+ non-native plants outside cultivation
• 79 plants cost US $97B per year
• Contribute to nearly half of threatened native spp.
7Area covered by 8 invasive plants in ONWR
8
But…what do plants have to do with frogs?
Physical structure
Invasive plants
9
But…what do plants have to do with frogs?
Physical structure
(Water) Chemistry
Invasive plants
10
But…what do plants have to do with frogs?
Physical structure
(Invertebrate) Community
(Water) Chemistry
Invasive plants
11
Invasive plants
Phragmites australis Typha angustifolia
12
13
Three basic questions
• Are there differences in water quality among invaded and non-invaded wetlands?
• If there are differences, do they affect the growth and survivorship of tadpoles?
• Do invasive plants affect the behavior of adult frogs?
14
Three basic questions
• Are there differences in water quality among invaded and non-invaded wetlands?
15
Hypothesis 1 methods
• Natural wetlands- 2007, 2008, 2011– Tested weekly over summer– P. australis, T. angustifolia, non-invaded
(doubly invaded in 2007)– LabPro datalogger
16
Natural wetland complexes
17
Water quality
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
8 9 10 11 12 13 14 15 16
Weeks
Am
mo
niu
m (
mg
/L)
Typha angustifolia
Phragmites australis
Non-invaded
Doubly invaded
Ammonium
18
Water quality
Dissolved Oxygen
4
4.5
5
5.5
6
6.5
7
7.5
8 9 10 11 12 13 14 15 16Weeks
Dis
solv
ed o
xyg
en (
mg
/L)
Typha angustifolia
Phragmites australis
Non-invaded
Doubly invaded
19
Water quality
Nitrate
0.1
0.2
0.3
0.4
0.5
0.6
0.7
8 9 10 11 12 13 14 15 16Weeks
Nit
rate
(m
g/L
)
Typha angustifolia
Phragmites australis
Non-invaded
Doubly invaded
20
Water quality
Temperature (2008)
5
10
15
20
25
30
1 2 3 4 5 6 7 8 11 12 13 14 15 16 17 18 19
Weeks
Tem
per
atu
re (
Cel
siu
s)
Typha angustifolia
Phragmites australis
Non-invaded
21
Highlights
• In ammonium, non-invaded wetlands consistently lowest
• In dissolved oxygen, T. angustifolia-invaded wetlands consistently highest
• In nitrate, non-invaded wetlands consistently lower
• Temperature consistently highest in non-invaded, lowest in invaded wetlands
22
Water quality: summary
Ammonium Dissolved oxygen
Nitrate Temp.
T. angustifolia 2 1 1 2
P. australis 1 3,2 3 2
Non-invaded 3 2,3 3 1
Doubly-invaded 1 1 2
2007, 2008
23
24
Three basic questions
• If there are differences, do they affect the growth and survivorship of tadpoles?
25
Lithobates clamitansLithobates catesbeianus
26
Larval growth and survival
• Natural wetlands- 2008, 2011– Tested weekly over summer– P. australis, T. angustifolia, non-invaded – Small enclosures with separate individuals
27
28
Larval survival
0
5
10
15
20
25
30
35
140
147
154
161
168
175
182
189
196
203
210
217
224
231
238
245
252
259
266
Day of Year
Ind
ivid
ua
ls p
er
en
clo
sure
Typha angustifolia
Phragmites australis
Non-invaded
Survival
29
Larval length:
0
5
10
15
20
25
30
35
140
147
154
161
168
175
182
189
196
203
210
217
224
231
238
245
252
259
266
Day of Year
Le
ng
th (
mm
)
Typha angustifolia
Phragmites australis
Non-invaded
Length
30
Growth rate
-1
0
1
2
3
4
5
6
7
8
140 147 154 161 168 175 182 189 196 203 210 217 224 231 238 245 252 259 266
Weeks
Gro
wth
(m
m/w
ee
k)
Typha angustifolia
Phragmites australis
Non-invaded
Growth rate
31
Relative Growth rate
-0.1
0
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
140 154 168 182 196 210 224 238 252 266
Weeks
Re
lativ
e G
row
th R
ate
Typha angustifolia
Phragmites australis
Non-invaded
Relative Growth Rate
32
Highlights
• Non-invaded consistently highest survival
• T. angustifolia consistently middle in length
• Non-invaded consistently highest in growth
• Non-invaded consistently highest in RGR
33
Summary of results
Survival Length Growth RGR
T. angustifolia 2 2 2 2
P. australis 2 3 3 2
Non-invaded 1 1 1 1
34
But…what do plants have to do with frogs?
Physical structure
Invertebrate community
Water chemistry
Invasive plants
35
36
Three basic questions
• Do invasive plants affect the behavior of adult frogs?
37
Adult behavior
• Adult behavior arenas
• Stem density mimicking natural setting
• Acclimation 15 minutes
• 15 minute trial
• Rest
• Repeat with all plants
38
Hypothesis 3 results
Lithobates clamitans
0.00
2.00
4.00
6.00
8.00
10.00
12.00
1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37
Individual Lithobates clamitans
To
tal
tim
e m
ovi
ng
Typha angustifolia
Phragmites australis
Non-invaded
T
P
N
39
Hypothesis 3 results
Lithobates clamitans
0.00
1.00
2.00
3.00
4.00
5.00
6.00
7.00
8.00
9.00
10.00
1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37
Individual Lithobates clamitans
Lo
ng
est
ind
ivid
ual
mo
vem
ent
Typha angustifolia
Phragmites australis
Non-invaded
P
T
N
40
Hypothesis 3 results
Lithobates clamitans
0
2
4
6
8
10
12
1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37
Individual Lithobates clamitans
Nu
mb
er o
f m
ove
men
ts
Typha angustifolia
Phragmites australis
Non-invaded
P
T
N
41
Hypothesis 3 results
Lithobates clamitans
0
1
2
3
4
5
6
7
8
1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37
Individual Lithobates clamitans
Nu
mb
er o
f "h
ang
-up
s"
Typha angustifolia
Phragmites australis
Non-invaded
P
T
N
42
Hypothesis 3 results
Lithobates catesbeianus
0.00
2.00
4.00
6.00
8.00
10.00
12.00
1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39
Individual Lithobates catesbieanus
To
tal
tim
e m
ovi
ng
Typha angustifolia
Phragmites australis
Non-invaded
T
P
N
43
Hypothesis 3 results
Lithobates catesbeianus
0.00
1.00
2.00
3.00
4.00
5.00
6.00
7.00
8.00
9.00
10.00
1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39
Individual Lithobates catesbeianus
Lo
ng
est
ind
ivid
ual
mo
vem
ent
Typha angustifolia
Phragmites australis
Non-invaded
T
P
N
44
Hypothesis 3 results
Lithobates catesbeianus
0
2
4
6
8
10
12
1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39
Individual Lithobates catesbeianus
Nu
mb
er o
f m
ove
men
ts
Typha angustifolia
Phragmites australis
Non-invaded
T
P
N
45
Hypothesis 3 results
Lithobates catesbeianus
0
1
2
3
4
5
6
7
8
1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39
Individual Lithobates catesbeianus
Nu
mb
er o
f "h
ang
-up
s"
Typha angustifolia
Phragmites australis
Non-invaded
T
P
N
46
0.00
2.00
4.00
6.00
8.00
10.00
12.00
14.00
16.00
1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37
Individual Lithobates clamitans
To
tal
dis
tan
ce
Typha angustifolia
Phragmites australis
Non-invaded
P
T
N
47
0.00
2.00
4.00
6.00
8.00
10.00
12.00
14.00
16.00
18.00
1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39
Individual Lithobates catesbeianus
To
tal
dis
tan
ce
Typha angustifolia
Phragmites australis
Non-invaded
T
N
P
48
0.00
2.00
4.00
6.00
8.00
10.00
12.00
14.00
1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37
Individual Lithobates clamitans
Dis
tan
ce f
rom
sta
rt
Typha angustifolia
Phragmites australis
Non-invaded
PN
T
49
0.00
2.00
4.00
6.00
8.00
10.00
12.00
14.00
1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39
Individual Lithobates catesbeianus
Dis
tan
ce f
rom
sta
rt
Typha angustifolia
Phragmites australis
Non-invaded
T
NP
50
Highlights
• More movements in non-invaded wetlands
• More time moving in non-invaded wetlands
• More hang-ups in invaded wetlands
51
Summary of results
• Water chemistry different in invaded wetlands
• Generally higher growth and survival in non-invaded wetlands
• Differences in movement in invaded wetlands
52
Future research
• Compare other invasive plants
• Invertebrate community effects
• Comparison with native relatives?
53
Acknowledgements
• Advisors- Oscar Rocha, Mark Kershner
• Committee- Ferenc de Szalay, Marilyn Norconk, Allison Smith
• Funding- Graduate Student Senate, Kent Environmental Council, Ohio Biological Survey, Ohio Native Plant Society, Society for the Study of Amphibians and Reptiles
54