New Jersey Fisheries in a Global Context
Olaf P. Jensen, Ph.D.
Rutgers University – olaf.p.jensen@gmail.com
Agenda
• 9:30 – 10:30 Global fisheries overview
• 10:30 – 10:40 Break
• 10:40 – 11:10 Fisheries research in Mongolia
• 11:10 – 11:20 Break
• 11:20 – 11:50 Radio tracking demonstration
• 11:50 – 12:30 NJ Black Sea Bass research
Objectives
• Understanding the “Global Fisheries Crisis” – a balance between food provisioning and conservation • Environmental impacts of fish compared to other protein sources
• Lessons for the conscientious consumer: two rules of thumb that don’t work and three that do
What I mean by a “fishery”
What is a “fishery” ?
•
A social‐ecological system organized around the harvest of wild marine/aquatic fish or invertebrates for use by humans.
Fish “stocks”
Fishermen
Management
Top 10 world fisheries (weight of landings)
FAO 2006
World fishery landings peaked in the 1980s
FAO 2006
“…it seems unlikely that the potential sustained yield of fish to man is appreciably greater than 100 million tons.”
‐ Ryther 1969, Science
Illegal, Unreported, and Unregulated (IUU) landings are large
Fishing effort and demand for seafood continue to grow
• 4 million fishing vessels
• landings worth 84.9 billion USD
• 2.6 billion people rely on fish for >20% of their animal protein (1/3 of global population)
FAO 2006
OLD TARGET
NEW TARGET
Impacts of fishing
Catch
OLD TARGET
NEW TARGET
Impacts of fishing
Catch
Biomass
OLD TARGET
NEW TARGET
Impacts of fishing
Catch
Biomass
Collapsed
Species
Source: Time magazine, November 2006
ALL FISH GONE BY 2048
Worm et al. (2006) Science 314:787‐790
What are the current status and trends of fisheries around the world?
Stock status worldwide
Fishing Intensity
Emergency Room
Recovery Room
Worm et al. 2009 Science
Fish Biomass
• 166 stocks
• 63% below MSY target
• 65% fished at rates below UMSY
Worm et al. 2009 Science
Fishing Intensity
Stock status worldwide
Fish Biomass
Stock status – selected regions
updated – 241 assessments
United States
New Zealand
Ricard et al. 2012
Europe
Canada
Recent local trends in fishing intensity and biomass
MSY
No species collapsed
Summary of global fisheries status
The bad news
• Two‐thirds of fish populations are below their target population size
• Many populations are collapsed (< 10% of their unfished population size)
• Overfishing continues on nearly a third of fish populations
The good news
• Many regions of the world have controlled excessive fishing pressure
• More than half of overfished populations are starting to recover
What should we eat?
• Nutrition and health
• Animal rights
• Environmental impacts
Data and images courtesy of Dr. Ray Hilborn
Environmental costs of food production
• Water use
• Pollution, fertilizer and pesticides
• Antibiotics
• Soil erosion
• Fossil fuels and greenhouse gas
• Biodiversity loss
Water consumption
Production method
Beef
Chicken
Pork
Sheep Goats
Capture fisheries
Water use cubic km
619
178
598
47
Near zero
Dead Zones
Pesticides
Fertilizer and Pesticide
Production Water Fertilizer Pesticides method
use millions thousands of cubic km of tons
tons
Beef
Chicken
Pork
Sheep Goats
Capture fisheries
619
178
598
47
12
13
20
2
76
79
121
15
0
0
0
Antibiotics
Antibiotics
Production Water Fertilizer Pesticides Antibiotics method
use millions of thousands tons
cubic tons
of tons
km
Beef
619
12
76
1,998
Chicken
178
13
79
5,085
Pork
598
20
121
4,994
Sheep Goats
Capture fisheries
47
2
15
114
0
0
0
0
Soil Erosion
Soil Erosion
Production Water use Fertilizer Pesticides Antibiotics Soil Loss method
cubic km millions of thousands tons
millions of tons
of tons
tons per year
Beef
619
12
76
1,998
307
Chicken
178
13
79
5,085
318
Pork
598
20
121
4,994
487
Sheep Goats
Capture fisheries
47
2
15
114
60
0
0
0
0
0
Energy intensity of food production
Crops
Land animals
Fish
Environmental costs per 40g protein
Water Fertilizer Pesticides Antibiotics Soil Loss
(L) (g)
(mg)
(mg)
(kg) 2200
50
494
21
16
Chicken 1331
18
163
55
3
Pork
1331
Dairy
1178
Capture fisheries low
46
34
422
299
53
50
8
7
0
0
0
0
Beef
Environmental costs per 40 g protein
Land Required CO2
(land use)
CO2
(no land use) (m2)
(kg)
(kg)
Beef
354
16.7
11.5
Chicken
1.4
2.5
1.4
Pork
Dairy
Capture fisheries
3.7
3.0
3.8
2.7
1.6
1.6
20‐100
0.3‐2.0
?
Fisheries have environmental impacts
• Abundance is reduced
• Some species will be depleted
• Ecosystems will be changed
Organic vegetable farming – the environmental ideal
Two rules of thumb that don’t work… and three that generally do
Two that don’t work
•Wild is better than farm raised
•Countries with better environmental records have more sustainable fisheries
Three that generally do
•Buy local
•Buy lower trophic level (lower on the food chain)
•Buy Marine Stewardship Council (MSC) certified
Delicious and sustainable local Farm‐raised mussels
seafood choices
Black Sea Bass
Atlantic Sea Scallop
Reliable seafood sustainability info:
fishwatch.gov
The problem with seafood sustainability cards or “The cod dilemma”
Atlantic cod
• Designed to send a price signal: reward sustainable fisheries, punish bad ones
• In well‐managed fisheries, catch is restricted when abundance declines
• Supply and demand can sometimes help fishermen weather the rebuilding period
• If seafood cards work as intended, they lower the price fishermen receive during rebuilding –
essentially punishing fishermen for doing the right thing
Conclusion
• All fisheries have environmental impacts
• All food sources have environmental impacts
• Well‐managed fisheries reduce impacts while providing food
• Consumers (and institutional food buyers) can reward good management through their seafood‐buying choices
1) Buy local
2) Buy lower on the food chain
3) Buy MSC certified
Questions?
Managing the World’s Largest
Trout, the Mongolian “River Wolf”
1.8 °C 0.6 °C
IPCC
Hucho taimen:
The River Wolf
Taimen (Hucho taimen)
Salmonidae
Family
Sub-family
Genus
Coregoninae
Salmoninae
Thymallinae
Salvelinus Salmo Oncorhynchus Hucho Brachymystax
Project location: Eg-Uur watershed, Mongolia
Taimen diet and growth
Climate change and thermal stress in
taimen
Temperature (C)
Uur River Water Temperature
July 2011
Late October
Late April
July 2012
Temperature-dependence of respiration
rates
Measure the decline
in dissolved oxygen in
a sealed tank. Repeat
over a range of
temperatures.
Taimen Movements
Taimen Movements
46 tagged taimen
> 4 years tracking
Movements: results
Home range size
Seasonal movements
Gilroy et al. 2010 Eco. Fresh. Fish
Acknowledgements
Science Team
Bud Mendee
Ganzorig
Amaraa
Norman-Mercado Silva
Brian Weidel
Tom Hrabik
John Waldman
Tim Zimmerman
David Gilroy
Jake Vander Zanden
Zeb Hogan
Kyle Hartman
Brian Roth
Sudeep Chandra
Students:
Talia Young
Ed McGinley
Mikaela Provost
Kirk Olson
Tyler Ahrenstorff
Ivana Roman
Corey Krabbenhoft
Trevor Krabbenhoft
Anna Hermes
Funding Sources
National Science Foundation
USAID (PEER Program)
National Geographic Society
Trust for Mutual Understanding
Mohammed bin Zayed Species
Conservation Fund
Partner Organizations
Taimen Conservation Fund
Institute of Geoecology
Mongol Ecology Center
Sweetwater Travel
Hovsgol Travel
11
Questions?
Nassau grouper
Protogynous
hermaphrodite
Clownfish
Protandrous
hermaphrodite
Blue-headed wrasse
Protogynous
hermaphrodite
Coral goby
Bi-directional sex
change
Photo credit: www.csl.cornell.edu, treesearn.com
11 hermaphroditic
stocks on the East
Coast
Black Sea Bass
Gag Grouper
Red Porgy
Red Grouper
Black Sea
Bass
Snowy
Grouper
Hogfish
Gag Grouper
Red Grouper
Gulf Yellowedge
Black
Grouper
1) How does fishery management address the
unique challenges of hermaphroditic fish?
a. Are sex changing fish more likely to
be overfished?
2) When does sex change happen in black sea
bass?
3) Does fishing have a differential impact on
males and females?
1) How does fishery management address the
unique challenges of hermaphroditic fish?
a. Are sex changing fish more likely to
be overfished?
2) When does sex change happen in black sea
bass?
3) Does fishing have a differential impact on
males and females?
Sex ratio
Gonochoristic species (no sexchange)
Age
Sex ratio
Gonochoristic species (no sexchange)
Age
Sex ratio
Gonochoristic species (no sexchange)
Age
Fishery
size
regulation
s
Fishery
size
regulation
s
Sex ratio
Protogynous hermaphrodite
(female Æ male)
Age
Sex ratio
Fishing mortality disproportionately affects males
Age
Aggressive behavior in male
territoriality and mate competition
Tiger grouper
Photo credit: www.reed.edu, Scott Heppell
Blue-headed
wrasse
Moyer and Nakazono (1978)
Warner and Swearer (1991)
Kline et al. (2011)
Sex ratio
Age
Disproportionately high male mortality
Sex ratio
Age
Disproportionately high male mortality
#1 - Increasingly
skewed sex ratios
#1 - Increasingly
skewed sex ratios
gag
snowy grouper
scamp
Species
Gag (Mycteroperca microlepis)
Scamp (Mycteroperca phenax)
California sheephead
(Semicossyphus pulcher)
Blue‐throated wrasse
(Notolabrus tetricus)
Snowy grouper
(Epinephelus niveatus)
CA sheephead
Location
Gulf of Mexico
Gulf of Mexico
California
South Australia
North & South Carolina
wrasse
Δ proportion male
Citation
Coleman et al. (1996)
Coleman et al. 36% to 18%
(1996)
Hamilton et al. 25% to 20%
(2007)
Shepherd et al. 10% to 5%
(2010)
17% to 1% 7‐23% to 1%
Wyanski et al. (2000)
Photo credit: FishBase
#1 - Increasingly
skewed sex ratios
gag
snowy grouper
scamp
Species
Gag (Mycteroperca microlepis)
Scamp (Mycteroperca phenax)
California sheephead
(Semicossyphus pulcher)
Blue‐throated wrasse
(Notolabrus tetricus)
Snowy grouper
(Epinephelus niveatus)
CA sheephead
Location
Gulf of Mexico
Gulf of Mexico
California
South Australia
North & South Carolina
wrasse
Δ proportion male
Citation
Coleman et al. (1996)
Coleman et al. 36% to 18%
(1996)
Hamilton et al. 25% to 20%
(2007)
Shepherd et al. 10% to 5%
(2010)
17% to 1% 7‐23% to 1%
Wyanski et al. (2000)
Photo credit: FishBase
Sex ratio
Age
Disproportionately high male mortality
#2 - Females will
change sex
earlier
#2 - Females will
change sex earlier
CA sheephead
ShrimpSpecies
Venus tuskfish
California sheephead
(Semicossyphus pulcher)
Venus tusk fish
(Choerodon venustus)
Roman
(Chrysoblephus laticeps)
Roman
Location
Δ in age or size
California
‐240 mm
Great Barrier Reef, Australia
‐4 mm
South Africa
Parrotfish
(Sparisoma viride)
(Sparisoma rubripinne)
(Scarus taeniopterus)
(Sparisoma aurofrenatum)
(Scarus iserti) Shrimp
(Pandalus borealis)
Parrotfish
Citation
Hamilton et al. (2007)
Platten et al. (2002)
‐2 years, 4 months Götz et al. (2008)
Caribbean Islands
‐7 mm
‐8 mm
‐6 mm
‐5 mm
‐4 mm
Hawkins and Roberts (2004)
Alaska
‐2 mm
Charnov and Anderson (1989)
Photo credit: FishBase
#2 - Females will
change sex earlier
CA sheephead
ShrimpSpecies
Venus tuskfish
California sheephead
(Semicossyphus pulcher)
Venus tusk fish
(Choerodon venustus)
Roman
(Chrysoblephus laticeps)
Roman
Location
Δ in age or size
California
‐240 mm
Great Barrier Reef, Australia
‐4 mm
South Africa
Parrotfish
(Sparisoma viride)
(Sparisoma rubripinne)
(Scarus taeniopterus)
(Sparisoma aurofrenatum)
(Scarus iserti) Shrimp
(Pandalus borealis)
Parrotfish
Citation
Hamilton et al. (2007)
Platten et al. (2002)
‐2 years, 4 months Götz et al. (2008)
Caribbean Islands
‐7 mm
‐8 mm
‐6 mm
‐5 mm
‐4 mm
Hawkins and Roberts (2004)
Alaska
‐2 mm
Charnov and Anderson (1989)
Photo credit: FishBase
Sex ratio
Age
Disproportionately high male mortality
#1 - Increasingly
skewed sex ratios
#2 - Females will
change sex
earlier
11 stock
assessments on the
East Coast
Black Sea Bass
Hogfish
Black
Grouper
Gag Grouper
Red Porgy
Black Sea
Bass
Red Grouper
Snowy
Grouper
Gag Grouper
Red Grouper
Gulf Yellowedge
Did the stock assessment …
11 stock
Black Sea Bass
- reportassessments
sex ratio at age or size?
Gag Grouper
- track change in sex ratio?
Hogfish
Red Grouper
- track changes in the size or age at sex change?
- include male and female in spawning biomass?
Black Grouper
Snowy Grouper
- evaluate differences in sex-specific mortality?
Red Porgy
Gulf Yellowedge
Did the stock assessment …
11 stock
Black Sea Bass
- reportassessments
sex ratio at age or size? 10 of 11
- track change in sex ratio?
Gag Grouper
2 of 11
Hogfish
Red Grouper
- track changes in the size or age at sex change? 4
of 11
Snowy Grouper
Black Grouper
- include male and female in spawning biomass? 9
of 11
- evaluate differences in sex-specific
mortality?Gulf0Yellowedge
of
Red Porgy
11
Status of exploited fish stocks
Legend
Gonochoristic
Hermaphrodite
Status of exploited fish stocks
Data from Ricard et al. 2012
Legend
Gonochoristic
Hermaphrodite
Status of exploited fish stocks
Hermaphrodite
stock are not
more likely to
be overfished
than non-sex
changing
stocks.
Data from Ricard et al. 2012
Legend
Gonochoristic
Hermaphrodite
Status of exploited fish stocks
Hermaphrodite
stock are not
more likely to
be overfished
than non-sex
changing
stocks.
Data from Ricard et al. 2012
Black sea bass in New Jersey
Photo credit: fishingcharters.com
Black sea bass in New Jersey
Commercial fishing traps
Recreational hook­and­line
Photo credit: Orion Weldon, Mikaela
Black sea bass in New Jersey
Recreational hook­and­line
Commerci
Recreational catch
al
Landings (mt)
Commercial catch
6,000
Anglin
g
1966
2006
1986
Shepherd and Nieland
(2010)
Biomass
Black sea bass were
overfished and
overfishing was
occurring prior 2006
Fishing mortality
Trends in the black sea bass fishery
1966
2006
Shepherd and Nieland
(2010)
Sex‐change is socially mediated (Benton and Berlinsky 2006)
Photo credit: Orion Weldon,
d
Field sampling
RUMF
S
Atlantic City,
NJ
Photo credit: Orion Weldon, Jenna
R k
Field sampling
Photo credit: Orion Weldon
Field sampling
Photo credit: Orion Weldon
Field sampling
Photo credit: Orion Weldon
Field sampling
Photo credit: Kistine Carolan, Orion
W ld
1) How does fishery management address the
unique challenges of hermaphroditic fish?
a. Are sex changing fish more likely to
be overfished?
2) When does sex change happen in black sea
bass?
3) Does fishing have a differential impact on
males and females?
Sex change
as a
function
of…
Sex
change
seaso
n
Sex change
as a
function
of…
Sex
change
size
Sex
change
age
Number of recaptures
Sex change as a function of season
Summer
Winter
Number of recaptures
Sex change as a function of season
n=
225
Summer
Winter
Number of recaptures
Sex change as a function of season
n=
225
changed
sex!
n=0
Summer
Winter
Number of recaptures
Sex change as a function of season
n=
225
changed
sex!
n = 15
n=0
Summer
Winter
Number of recaptures
Sex change as a function of season
n=
225
changed
sex!
n = 15
n=7
n=0
Summer
Winter
Number of recaptures
Sex change as a function of season
n=
225
0
%
47%
changed
sex!
n = 15
n=7
n=0
Summer
Winter
Sex change as a function of body size
n=
126
Sex change as a function of body size
n=
126
All
sex changing fish were 4-5
years
Proportion male
Sex ratio at age
Age
Proportion male
Sex ratio at age
sex
chang
e
Age
Proportion male
Sex ratio at age
sex
chang
e
0.37
Age
1) How does fishery management address the
unique challenges of hermaphroditic fish?
a. Are sex changing fish more likely to
be overfished?
2) When does sex change happen in black sea
bass?
3) Does fishing have a differential impact on
males and females?
All fishing methods
have size selectivity
frequency
Selectivity: the sample bias obtained by fishing gear
?
length
Population distribution
Selectivity curve
Catch distribution
Asymptotic Dome‐shaped
Distinct sex-specific behavior in sex-changing species
Tiger grouper
(territoriality)
California
sheephead
(mate competition)
Blue-headed
wrasse
(harem)
Nassau grouper
(spawning
aggregations)
Photo credit: seapics.com, biosch.hku.hk/ecology/ys.htm, www.uwphotographyguide.com
Length
(mm)
Probability of
Recapture
Probability of
Recapture
P(males in
traps)
P(males by
angling)
Length
(mm)
Probability of
Recapture
P(males in traps)
P(males by
angling)
P(females in
traps)
P(females in
pots)
Length
(mm)
Probability of
Recapture
P(males in
traps)
P(males by
angling)
P(females in
traps)
P(females by
angling)
Length
(mm)
Traps
Hook-andline
Major conclusions:
• Sex change is not accounted for in most stock assessments.
• Hermaphroditic stocks are not more likely to be overfished than
gonochoristic stocks
• Approximately 50% of female black sea bass are expected to
change sex over the winter from 2011 to 2012
• At 365 mm and at age 4, 50% of females are expected to change
sex
• In black sea bass, males and females experience different
probabilities of capture by size and gear; commercial traps capture a
higher proportion of males than angling, but large males are most
likely to be captured by hook-and-line gear.
Acknowledgeme
nts
Field work:
Volunteer fishermen (>80)
Mike Wun
Evan Kwityn
Chris Filosa
Anthony Vastano
Andrew Hassall
Talia Young
Jennifer Pincin
Katie Wright
Jason Morson
Phil Neubauer
Orion Weldon
Eleanor Bochenek
Funding:
NOAA – Research Set Aside program
Rutgers University
Manasquan River Marlin & Tuna Club