Post on 25-Sep-2020
transcript
Stephanie Green David H. Smith Conservation Research Fellow
Oregon State University
Invasive Indo-Pacific lionfish in the Western Atlantic
2
Collaborators and funders Lad Akins, Reef Environmental Education Foundation Mark Hixon, Oregon State University Bernard Castillo and Kynoch Reale-Munroe, University of the Virgin Islands Ian Lundgren and Vanessa McDunough, National Park Service Isabelle Côté and Andrew Cooper, Simon Fraser University Nick Dulvy, IUCN Shark Specialist Group Nicola Smith, Bahamas Department of Marine Resources Annabelle Brooks, Cape Eleuthera Institute Skylar Miller, University of the West Indies James Morris, NOAA CCFHR
Distribution Red Lionfish – Pterois volitans Devil Firefish – Pterois miles
Source of the invasion
Aquarium imports and non-native fish sightings
Semmens et al. 2004
Invasion progression
USGS Non-indigenous Aquatic Species Database 2013
Invasion progression
USGS Non-indigenous Aquatic Species Database 2013
Invasion progression
USGS Non-indigenous Aquatic Species Database 2013
Invasion progression
USGS Non-indigenous Aquatic Species Database 2013
Invasion progression
USGS Non-indigenous Aquatic Species Database 2013
Invasion progression
USGS Non-indigenous Aquatic Species Database 2013
Invasion progression
USGS Non-indigenous Aquatic Species Database 2013
Invasion progression
USGS Non-indigenous Aquatic Species Database 2013
Lionfish life cycle
Green et al. 2012 PLoS ONE
Lionfish abundance has increased rapidly
Green et al. 2012 PLoS ONE
Lionfish abundance has increased rapidly
Relative predator abundance Eleuthera, Bahamas
0
5
10
15
20
25
30
35
40
lionfish nassau grouper
black grouper
graysby
Fish
per
10
0 m
2
Green et al. 2012 PloS ONE
Lionfish in the Loxahatchee River
Judd and Layman 2012
Morris 2009
Potential lionfish range
100°W 80°W 60°W 40°W 60°N
40°N
20°N
0°
20°S
40°S
Morris & Whitfield 2009
Why are lionfish so successful in the Atlantic?
Lionfish venomology
Lionfish are venomous
Maljković et al 2008 Coral Reefs
Predators do not control lionfish
Anecdotal observations
Experimental feeding trials
Morris et al 2011 J Exp Marine Biol Valdivia et al. 2014 PeerJ
Predators do not control lionfish
Gape-limited predators
What is the effect of lionfish predation on invaded fish communities?
The Bahamas
The Bahamas
New Providence Island
Eleuthera Island
Lionfish reduce prey biomass
By 65% over two years
Green et al. in review
Green et al. 2012 PLoS ONE
Eleuthera, Bahamas Lionfish removal experiment
Testing targets for lionfish control
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Prey fish recovery P
rop
ort
ion
ch
ange
0
-0.5
1.5
2.0
Green et al. in press Ecol. App.
Conservation and lionfish control Management plans
Conservation and lionfish control Awareness and education
Conservation and lionfish control Regional action
Complete eradication is unlikely
Population suppression
Eradication
The goal:
Make the most effective use of limited resources for control
Conservation application Minimize ecological impacts in priority areas
Juvenile fish habitat Marine Protected Areas
Conservation application Minimize ecological impacts in priority areas
Recolonization happens rapidly Li
on
fish
10
0 m
-2
Date Green et al. in review Cons. Letters
What level of control is required to mitigate the effects of lionfish?
44
Pre
y fi
sh b
iom
ass
Lionfish density
Sufficient removal
Insufficient removal
How many lionfish can a reef tolerate?
What is the cost and effort needed
for control?
How often to remove?
Florida Keys National Marine Sanctuary
Biscayne National Park
c
c
Buck Island National Monument
Long term removal studies Florida Keys St Croix, USVI
John Pennekamp State Park
How many lionfish to remove?
0
1
2
3
4
5
6
7
8
9
I1 I2 LF4 LF5 P1 P3 P5 P7
Lio
nfi
sh
ab
un
da
nc
e
Site
How many lionfish to remove?
0
1
2
3
4
5
6
7
8
9
I1 I2 LF4 LF5 P1 P3 P5 P7
Lio
nfi
sh
ab
un
da
nc
e
Site
Starting density
Removal target
Densities 45-85% higher than target
Bi-monthly dives to survey and remove lionfish
0
2
4
6
8
10
1 2 3 4 5
Removal event
Site I1 0
2
4
6
8
1 2 3 4 5
Removal event
Site P5
0
1
2
3
4
5
1 2 3 4 5
Removal event
Site LF5
P1
P3
P7 P5
I1 I2
LF4
LF5
How many lionfish to remove?
Target density
USGS Non-indigenous Aquatic Species Database 2012
Where do we get the manpower to achieve control?
Tools for lionfish control Primarily caught by spear and hand-net
Tools for lionfish control Food fishery
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Eat ‘em to beat ‘em!
Lionfish derbies
What is a lionfish derby?
Lionfish derbies are an effective tool for increasing awareness….
But how effective are they at suppressing lionfish populations?
Green Turtle Cay, Bahamas Derby effectiveness
study
Key Largo, Florida
Pre- and post- derby surveys
Lionfish tagging
Derby fishing maps
Before After Before After
g li
on
fish
ha-1
Derby No derby
45% decline
Key Largo, Florida
Summary
•Invasive lionfish are having significant effects on fish populations across the Atlantic, Caribbean and Gulf of Mexico •Controlling lionfish below predicted ‘thresholds’ densities can prevent ecological impacts •How can you help?
•Support lionfish control research •Support lionfish control efforts (e.g. derbies, food fishery)
Thank you Contact:
greenst@science.oregonstate.edu
@steph_j_green
www.stephaniejgreen.com
Find out more:
www.reef.org/lionfish
http://coastalscience.noaa.gov/research/pollution/invasive/lionfish