Transcript Guidelines for incorporating fish distribution shifts into a stock

Managing Lower Trophic Level
Species in the Mid-Atlantic Region
Forage Fish Workshop
Mid-Atlantic Fishery Management Council
Raleigh, North Carolina
11 April 2013
E. D. Houde
Northwest Atlantic Coastal and Shelf Ecosystems
Productive Coastal Zone
Major Productive Estuaries
Connected to Southern New
England and Georges Bank
Connected to South Atlantic
shelf ecosystems
Bounded by the Gulf Stream
Strongly seasonal
Productivity of NW Atlantic Shelf
Ecosystems
Primary Production
Productivity on a par with Southern
New England and Georges Bank
Chlorophyll a
NEFSC Ref Doc 12-07
Candidate MA Forage Species
Species
Fished
Retained
Discarded
Bycatch
Bycatch
___________________________________________________________________
Butterfish
yes
yes
yes
Atl. mackerel
yes
no
yes
Longfin squid
yes
yes
yes
Illex squid
yes
yes
yes
Atl. herring
yes
?
yes
Atl. Menhaden
yes
no
yes
River herrings
no
no ?
yes
Sand lance
no
no
no
Round herring
no
no
yes
Sardines
no
no
?
Anchovies
no
no
?
Who are the Major Predators?
MAFMC SSC ESC “Definition
Regular info input to OFL/
ACL/ABC process
NEW
N
Is this a forage stock?
Y
Stop, Apply Regular
ABC Control Rules
N
Treat as NS 1 Ecosystem
Component species
Is the stock retained in
a fishery?
Y
Y
Is this a bycatch
only fishery?
N
N
Are there adequate
catch (landings)
data?
Address in
Primary fishery
Are there adequate
biomass data?
Get data, be
precautionary
N
Y (Use B proxies)
Y
N
Is there an accepted
stock assessment/
w/OFLs?
Are stock catch (landings, or B
proxies) <, =, or > PP threshold?
N
Y
Mild increase
to OFL buffer
Y
N
Does SA include
predation directly (M2)?
Y
Increase
buffer to
OFL proxy
<, =
Y
Does SA consider
predation at all?
>
Decrease to
OFL buffer
Apply Regular ABC
Control Rules
N
Are Landings
(catch) stable?
Managed Forage Species
Modified Council Risk Policy
forage
typical
atypical
45
Probability of Overfishing
40
35
30
25
20
15
10
5
0
0
0.5
1
1.5
2
2.5
3
B/Bmsy
Can the MAFMC Develop a Forage Policy?
North Pacific Council
Ecological Considerations for Forage
•
•
•
•
•
•
•
•
Groundfish FMPs have a forage category as part of the ecosystem
component (EC) of the fishery (8 families and 1 order); directed federal
fisheries prohibited with 2% (fish on board) bycatch cap for this EC forage
group
M2 (predation mortality) term incorporated in stock assessments (where
possible); increasing number of multi-species assessment models being
developed
PDTs and SSC evaluate trends in M due to predation when setting ABC for
target species (may reduce ABC below max allowed if warranted)
Increased biomass thresholds for commercially-important prey species to
insure adequate forage for Stellar sea lions (reduced fishing as biomass
thresholds are approached);
Time/area restrictions to avoid local depletion
Ecosystem Considerations Report appended to groundfish and crab SAFE
documents
Established system OY cap for BSAI (85% of sum of MSYs for managed
species) and GOA groundfish fisheries (95% of sum of MSYs for managed
species)
Most recently developed Arctic FEP which includes system level cap=zero
PFMC Coastal Pelagics
Species (CPS) FMP
• Includes Pacific sardine, chub mackerel,
northern anchovy, jack mackerel, market
squid, and krill (euphausids)
• Council banned harvest of krill in west
coast EEZ (to prevent directed fishery
development) in 2006
• Sardine and chub mackerel are actively
managed, others are “monitored” species
PFMC: Amendment 13 (Sept 2011) to
CPS FMP
• Modified existing harvest control rules to
include ABC buffer relative to OFL through
a combination of scientific advice from
SSC and a policy determination of the
Council (based on Council risk tolerance)
• Amendment 13 maintained default
harvest control rules for monitored stocks
(ABC equals 25% of OFL/MSY)
CPS Harvest Control Rules
• Contain “cutoff” biomass reference points
• Cut-off is defined as biomass level below which
directed fishing is prohibited
• Pacific sardine cutoff is 150,000 mt (or three
times the overfished threshold); the control rule
also contains environmental parameters to
explicitly adapt harvest levels in response to
environmental variability
Coastal Pelagic Species: PFMC
Managed Species Control Rule
• OFL = Biomass x Fmsy x Distribution
• ABC = Biomass x Buffer x Fmsy x Distribution
• ACL ≤ ABC
General Harvest Control Rule
• HG = (Biomass – Cutoff) x Fraction x Distribution
• ACT = HG or ACL, whichever is less
• MAXCAT also is defined
The Harvest Control Rule Assures that Exploitation Rate Declines Continuously
as Biomass Declines
PFMC FEP Initiative 1
• Council proceeding with development of FEP
Initiative 1 – protection for un-fished forage
species
• Objective is to prohibit development of new
directed fisheries on forage species until Council
has adequate opportunity to assess the science
relating to any proposed fishery and any
potential impacts to existing fisheries and
communities
• Developed inventory of un-fished forage species
and currently authorized gears and fisheries in
US west coast EEZ
SSC National Workshop IV: EBFM
and Forage Fish Issues
• Need better ways to estimate forage
biomasses
• Need better ways to estimate predator
demand
• Determining M2 is important
• Ecosystem forage buffers vs singlespecies buffers?
For consideration
• Indicators and reference points
• Are there any rules of thumb, e.g., F < M, Biomass
threshold, hockey-stick (Restrepo, Lenfest) rules,
appropriate F and B levels.
• Can predator demand be indexed from stock
assessments of predators?
• What indices of ecosystem state are available that are
indicative of predator demand and prey availability?
• Can energetics modeling be useful to estimate demand?
• What about ecosystem modeling? Strategic or tactical?
• What decisions and regulations could be implemented
by managers in the short term?
Leave one third for the birds
Cury et al. 2011
Atlantic Menhaden
Chesapeake Bay
Integrated Biomass
Size Spectrum
Log2 A (abundance)
(combined 1997 and 1999 data)
phytoplankton
mesozooplankton
Fish larva
Zooplanktivorous
small fish
Piscivorous
large fish
2 m
20 m
200 m
2 mm
20 mm
Organism Size
20 cm
Menhaden: Allocation and EBFM
Bluefish
Commercial Fishery
Predators/Piscivores
Striped Bass
Weakfish
Osprey
What is a “Fair” Allocation Plan?
Can Humans Cause
“Localized Depletion?”
Recreational Striped Bass Fishing