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 NewEngland and Georges Bank

Connected to South Atlanticshelf ecosystems

Bounded by the Gulf Stream

Strongly seasonal

Primary Production

Chlorophyll a

Productivity of NW Atlantic ShelfEcosystems

NEFSC Ref Doc 12-07

Productivity on a par with SouthernNew England and Georges Bank

Candidate MA Forage Species

Species Fished Retained Discarded Bycatch Bycatch

___________________________________________________________________Butterfish yes yes yesAtl. mackerel yes no yesLongfin squid yes yes yesIllex squid yes yes yesAtl. herring yes ? yesAtl. Menhaden yes no yesRiver herrings no no ? yesSand lance no no noRound herring no no yesSardines no no ?Anchovies no no ?

Who are the Major Predators?

MAFMC SSC ESC “Definition

Is this a forage stock?

Is the stock retained in a fishery?

Is this a bycatch only fishery?

Is there an accepted stock assessment/ w/OFLs?

Does SA consider predation at all?

Does SA include predation directly (M2)?

Regular info input to OFL/ ACL/ABC process

Y

N

Y

Y

>

Y

NY

N

N

N

N

<, =

Y

Stop, Apply Regular ABC Control Rules

Treat as NS 1 Ecosystem Component species

Are Landings (catch) stable?

Mild increase to OFL buffer

Apply Regular ABC Control Rules

Address in Primary fishery

Decrease to OFL buffer

Are stock catch (landings, or B proxies) <, =, or > PP threshold?

Increase buffer to OFL proxy

Y N

NEW

Are there adequate catch (landings) data? Y

N

Are there adequate biomass data?

Y (Use B proxies)

N

Get data, be precautionary

0

5

10

15

20

25

30

35

40

45

0 0.5 1 1.5 2 2.5 3

B/Bmsy

Pro

bab

ility

of

Ove

rfis

hin

g

typical

atypical

forage

Managed Forage Species

Modified Council Risk Policy

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 Continuouslyas 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 single-

species 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

Y = -1.03 X – 2.73

phytoplankton

mesozooplankton

Fish larva

Zooplanktivoroussmall fish

Piscivorouslarge fish

Log 2

A (

abun

danc

e)

200 m 2 mm 20 mm 20 m 20 cm2 m Organism Size

Chesapeake Bay Integrated Biomass Size Spectrum(combined 1997 and 1999 data)

Bluefish

Weakfish

Striped Bass

Predators/PiscivoresCommercial Fishery

What is a “Fair” Allocation Plan?

Can Humans Cause “Localized Depletion?” Recreational Striped Bass Fishing

Osprey

Menhaden: Allocation and EBFM