Effects of fishing on community size-structure

Slides:

Advertisements

Similar presentations

Economic value of sustainable fisheries

Advertisements

Overview of Northeast Atlantic Stocks Seminar State of Fish Stocks in European Waters (Brussels, September 17, 2013) Carmen Fernández, ICES ACOM vice-chair.

Some Comments on SSB msy and Indicators of Healthy Size Structure Rainer Froese, GEOMAR WKGMSFD D3 Copenhagen, 4-5 September 2014.

458 Delay-difference models Fish 458, Lecture 14.

Proper Implementation of the MSY-Concept in the CFP European Parliament Brussels, 29 Nov 2011 Rainer Froese, IFM-GEOMAR.

Population Interactions Competition for Resources: –Exploitative competition: Both organisms competing for the same resource(s). –Interference competition.

Plankton changes and cod recruitment in the North Sea Plankton changes and cod recruitment in the North Sea Grégory Beaugrand 1,3*, Keith M. Brander 2,

NORWEGIAN LEGISLATION ON THE DISCARD BAN – A BRIEF INTRODUCTION by Arne Wåge, The Directorate of Fisheries, Tromsø, June 2007.

Remaining Issues with the CFP Reform Rainer Froese, GEOMAR Breakfast Discussion with Fisheries Attachées 6th March 2013, WWF Office, Brussels.

1 Full Accounting for Catches An increasing necessity for sustainable fisheries management.

The Cod Day Marine Laboratory, Aberdeen, 2 October 2012 The Cod Day - Science Coby Needle, Nick Bailey, Rui Catarino, Steven Holmes Marine Laboratory Aberdeen.

ICES advice as of 30th June 2014 Nick Bailey, Coby Needle, Helen Dobby, Emma Hatfield Marine Scotland - Science.

Climate and currents. Temperature in Kola section.

The Effects of Fishing on Non- target species and Ecosystem Structure and Function Henrik Gislason University of Copenhagen, Denmark.

European Fisheries Management Rainer Froese IFM-GEOMAR.

Glacial Rebound Glacial Rebound Studies depend on many factors. What are they ? Ice load History of the load Ocean water load on coastlines and globally.

Clupeid and Gadoid Fisheries

Many Ways to Estimate Bmsy

Fisheries Question: Why do we worry about “over-fishing” the ocean and running out of fish, but not “over-raising” cows and pigs on land and running out.

What lies beneath the surface: Exploring our fisheries in depth

Fishing as the exploitation of a natural resorce By Eskild Kirkegaard, ICES ACOM Chair ARVI International Conference on the Future of Fisheries Vigo, 27.

Status of Exploited Marine Fishes and Invertebrates in German Marine Waters Rainer Froese, GEOMAR Cluster Meeting ökosystemgerechte Fischerei Bundesamt.

US-GLOBEC NW Atlantic Georges Bank Program Broadscale cruises (Jan-June) Process cruised 1995, 97 and 99 (Mar-May) Growth rate of

Baltic fishing: is there a future? Lysekil 25 May 2006 Bengt Sjöstrand Inst. of Marine Research.

60º Introduction and Background ù The Barents Sea covers an area of about 1.4 x 10 6 km 2, with an average depth of 230 m. ù Climatic variations depend.

European sea bass management Lisa Readdy, Cefas. 18/09/2013.

Preparing for ecosystem-based fisheries management: A Namibian case study Nico E. Willemse International Symposium “Marine fisheries, ecosystems, and societies.

Two Promising Methods for Assessment of Data-Poor Stocks Rainer Froese, GEOMAR, Germany Daniel Pauly, FC-UBC, Canada 9 November 2014, San Francisco, USA.

Centre for Ecological and Evolutionary Synthesis ICES/NAFO Decadal Symposium Santander, Spain May 12th 2011 The serial recruitment failure to North Sea.

Chinook Salmon Supplementation in the Imnaha River Basin- A Comparative Look at Changes in Abundance and Productivity Chinook Salmon Supplementation in.

ICES plans 2014 forward. ICES work 2014 Recurrent TAC advice – Sandeel 28/2 – NS main package 30/6 – Rays and skates 30/9 Data limited stocks – DLS categories.

Biodiversity of Fishes: Life-History Allometries and Invariants Rainer Froese

The Fisheries Facts and Figures about Fisheries in Nova Scotia Source: D.F.O.

Comparative analysis of the community structure and trophic relations of the Peruvian hake Merluccius gayi peruanus and its by-catch of the years 1985.

Bentorcha, Gascuel, Colléter, Guénette- Ecopath 30 years, Barcelona, November 2014 EcoTroph to assess changes in marine ecosystems - Application.

Balanced Harvesting: Not Supported by Science Rainer Froese GEOMAR, Kiel, Germany Pew Fellows Meeting, Rio Grande 16 October 2015.

Atlantic Herring Conservation Lauren Keyes Yu Kawakami Brigette Jones.

1 Assessing Vulnerability of Living Marine Resources in a Changing Climate Roger Griffis Climate Change Coordinator, NOAA Fisheries Service.

Two Peak Production Case Histories: Texas and North Sea Crude Oil Production 1999 North Sea Peak 1972 Texas Peak.

Lecture 1 review Why managers cannot avoid making predictions Approaches to prediction Components of population change What is a “population”? How natural.

Population Dynamics and Stock Assessment of Red King Crab in Bristol Bay, Alaska Jie Zheng Alaska Department of Fish and Game Juneau, Alaska, USA.

1 2 Georges Bank multispp assessment project Goal: Harvest advice Goosefish Dogfish Winter Skate Herring Mackerel Winter.

What is the order of the graph?

California Healthier Living Coalition Meeting

Can you name these fish? Cod Herring Mackerel Haddock.

Export of dissolved organic carbon from peatlands under elevated carbon dioxide levels Crystal Lebreton.

Age-structured models Yield-per-recruit, reference points, MSY

The Failure of the Common Fisheries Policy

Mid-Atlantic Fishery Management Council

Figure 1. Distribution of pelagic fish stocks.

Identifying chokes Stuart Reeves

Integrating biological components into a spatially explicit, complex economic model for fisheries management evaluations: The North Sea saithe fishery.

Dissemination Workshop for African countries on the Implementation of International Recommendations for Distributive Trade Statistics May 2008,

Multy- Objective Differential Evolution (MODE)

Communication between organisms

Many Ways to Estimate Bmsy

Facts and Figures about Fisheries in Nova Scotia Source: D.F.O.

Biodiversity of Fishes Stock-Recruitment Relationships

Lakes & Large Impoundments Chapter 22

فرایند تسهیلگری در مددکاری جامعه ای

What is Strategic Performance Management (SPM)?

Weight-Length Relationships

What connects these images?

ICES Advice for 2015 – Sea bass

MATH(O) Limits and Continuity.

Update on previous year’s discussion on Descriptor 3

Remaining Issues with the CFP Reform

Presentation transcript:

A decade in the doldrums: depressed size-structure in the Celtic Sea fish community

Effects of fishing on community size-structure Fishing is selective and directly removes large individuals/species Removal of large piscivores leads to predation release which indirectly enhances small fish biomass

Shift from large to small fish dominated community

Size-based indicators Direct and indirect effects of fishing can be integrated by metrics like the Large Fish Indicator (LFI): Proportion by weight of ‘large’ fish = Where ‘large’ is derived from the data

LFI responds to F (lag). Sustained F in the Celtic Sea until 2002 Peak LFI in 1990 - low levels throughout the 2000s

Fishing (+ discarding) of ‘recruits’ prevents recovery (Monkfish, Hake, Cod, Haddock) M + G R M + G G + F G + F G + F

Models suggest a multi-decadal recovery period, asymptote depends on F history

Perturbed system with LFI well below 1990 No recovery during 2000s due to sustained F Some good recruitments but low survival Recovery depends on F history Decadal process - full recovery not guaranteed