Growing recreational impact, often declining commercial impact

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Recreational fisheries
management
Issues and options
Recreational fisheries are
IMPORTANT
• According to NMFS, the total landed value
of US commercial fisheries in 2009 was
$2.29 billion (FAO says $31 billion, not
clear why since doesn’t agree with
tonnage reported to FAO)
• US marine recreational fisheries were
valued at of $12 billion, almost 1/3 Florida
Characteristics of recreational fisheries
• Most often “open access”, no effort limitation
• Very high economic value to small communities,
rural areas (shift leisure spending from urban
activities)
• Typically take over from commercial fisheries
when in competition (strong political voice, lots
of voters)
• Rarely cause biological overfishing (effort
responds strongly to reduced abundance)
• Create severe quantity-quality tradeoff problem
Vulnerability exchange process
typically limits catch per effort
Invulnerable fish
Smart, inactive,
resident in safer
places (eg deep)
vulnerable fish
Stupid, active,
resident in places
where gear works
and access is best,
typically <10% of
total fish
cpue
Vulnerable density (cpue)
CPUE typically very sensitive to
fishing effort
Fishing effort
• CPUE often 510x higher at
low efforts,
because first
increments in
effort enjoy
high catch
rates, deplete
vulnerable pool
(foraging arena
equation effect)
Fishing effort
Effort responses prevent increases
in cpue
Total Fish Abundance
• Typical response
is nearly linear
• Linear increase
predicted if
vulnerable
density held
roughly constant:
c=co/(1+qE)
E=1/q(co/c-1)
(co=cpue at zero
effort, c=cpue at
equilibrium)
Approaches to recreational
fisheries regulation
• Size and bag limits (almost universal)
• Seasonal closures (common)
• Production side, hatcheries (common, do
not increase cpue)
• Spatial closures, MPAs (uncommon so far)
• Limited entry--access management,
license lotteries, etc. (very uncommon)
This will not
be an
objective
presentation;
my interest is
in insuring
that Junior
and I can
keep doing
this
Growing recreational impact, even with
restrictive bag and size limits, as for
gag grouper in the Gulf of Mexico
Growing recreational impact often
simply replaces commercial impact
Pompano, West Florida Coast
600000
500000
Catch
400000
Commercial
Sport
Commercial
Net ban
300000
200000
100000
0
1982 1984 1986 1988 1990 1992 1994 1996 1998 2000
Book/Pompano.xls
So we are going to face progressively
more severe restrictions as demand for
both fishing and conservation grow
•
•
Open access fisheries lead to a syndrome
of “success breeds failure”: effort expands
until quality of fishing declines
There are two basic ways to restrict fishing
mortality in open-access fisheries:
–
–
•
Reduce effective effort through bag limits, size
limits, closed seasons
Spatial closures (protected areas)
Spatial and seasonal closures lead to
concentration of fishing near closed area
boundaries and at season openings
The quality-quantity tradeoff:
Most of us end up getting screwed,
most of the time
Quantity
(angling effort)
Quality
(cpue, size)
LOW COST
Unguided
HIGH COST
Guided
Cedar Key (10 min.)
Vancouver (2 hr travel)
Public access
Suwanee (60 min.)
Chilcotin (7 hr travel)
Private
Most of us hate the very idea of
spatial closures; I certainly do
• But then I got to thinking about why I can still
catch lots of spotted sea trout and red drum in
my back yard in Cedar Key, Florida: most of the
time, most of those fish are not in spots where
people can catch them, i.e. the fish are in natual
“marine protected areas”
• And I started connecting that thinking with the
stock assessment and modeling work that I do
when I replace my fishing hat with my scientist
hat (which thankfully isn’t too often anymore).
Mindless combination of size and
bag limits can even cause worse
conservation problems
25
23
21
0.8-1
19
17
0.6-0.8
0.4-0.6
0.2-0.4
15 Size Lim it
0-0.2
13
11
9
9
7
5
3
7
1
In this grouper example,
green represents healthy
recruitment levels, and
red is severe overfishing.
For low bag limits,
increasing the size limit
actually causes
recruitment to decrease
(move from green to
yellow zone).
5
Bag Lim it
Combining these regulations is kind of
like taking Viagra and Valium at the
same time: it might work, but…
Recent models for predicting redistribution
of fish and fishing when areas are protected
(MPAs) indicate that sustainable sport effort
should often increase as closed area is
increased
Total
sport
fishing
effort
sustained
Not
enough
fishing
ground
Not
enough
fish
0%
Area closed to fishing
100%
EDOM model predictions of Gulf of
Mexico red snapper fishing effort
EDOM random MPA siting algorithm
Gulf of Mexico red snapper
Equilibrium fishing effort
60
50
40
30
20
10
0
0
20
40
60
80
Percent of total area closed
100
For the red snapper example,
MPAs might result in widely higher
efforts, not just at MPA boundaries
Gulf of Mexico red snapper EDOM prediction
No MPAs
Optimum MPA design
1.2
1
0.8
0.6
0.4
0.2
0
TX
TX
TX
TX
TX
TX
TX
TX
TX
TX
TX
TX
TX
LA
LA
LA
LA
MS
MS
MS
MS
MS
AL
AL
AL
FL
FL
FL
FL
FL
FL
FL
Equilibrium fishing effort
1.4
Coastal location (Texas to Florida)
A promising alternative: rotating
closures (fallow rotation)
• Advantages
– Increased total yield
when discard mortality
is high
– Larger average fish
size if used with size
limits
– Increased cpue and
number of fish kept
– Assures meeting
Federal fishing
mortality rate limits
• Disadvantages
– Effort concentration,
competition
– Low cpue late in
openings
– Encourages cheating
(enforcement issue)
Rotating closures for West Florida
grouper management
OPENINGS:
2008, 2012, …
2009, 2013, …
2010, 2014, …
2011, 2015, …
Strips as shown are 0.1
degree (6 nm, 10 km)
north-south; larger
strips would be safer,
but would more
seriously limit local
access to good
grounds
Year
80
60
40
20
0
2028
2026
2025
2023
2022
2020
2019
2017
2016
2014
2013
2011
2010
2008
2007
2005
2004
2002
2001
1999
1998
1996
1995
1993
1992
1991
1989
1988
1986
2032
100
2031
120
2032
CATCH PER EFFORT
2031
But catch per effort could be depressed
2029
Year
2029
2028
2026
2025
2023
2022
2020
2019
2017
2016
2014
2013
2011
2010
2008
2007
2005
2004
2002
2001
1999
1998
1996
1995
1993
1992
1991
1989
1988
1986
Catch/effort (kg/day)
Total Catch (mt)
Predicted gag grouper performance
Annual total catch should remain high
CATCH
3000
2500
2000
1500
1000
500
0
Gag grouper policy options and
performance tradeoffs
Policy
MSY (Current policy, 51 cm size)
Rotating, 51 cm min size
Rotating, no min size
Yield (mt)
2281
2455
2369
Catch Trophy Catch
Egg Waste
(1000 fish) (1000 fish) production (1000 fish)
622
133
15.33
264
574
169
15.06
234
1485
129
13.63
0
Even if we permanently solve conservation
problems by using closed areas (MPAs, rotating
openings), this problem will remain:
Most of us end up getting screwed,
most of the time
Quantity
(angling effort)
Quality
(cpue, size)
LOW COST
Unguided
HIGH COST
Guided
Cedar Key (10 min.)
Vancouver (2 hr travel)
Public access
Suwanee (60 min.)
Chilcotin (7 hr travel)
Private
Should it be public policy that you
only get what you pay for?
• Attempts to improve quality in openaccess public fisheries just result in
increased fishing pressure, until quality
declines to where it was.
• The only way to stop this is to deliberately
restrict effort.
• One “fair” way to restrict effort is through a
lottery system of some kind (like drawing
permits for big game hunting).
So how do we keep the rest of you
buggers out of my back yard?
• Boat ramp quotas
• Resident-only open
areas (in my dreams)
• Fishing club TURFS
(like trout in Austria)
• Misinformation to
sports writers
• Any other ideas???
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