What is the status of fish stocks around the world …...Status of fish stocks around the world and...

What is the status of fish stocks around the world and the role of fisheries management?

Ray HilbornSchool of Aquatic and Fishery Sciences

University of Washingtonhilbornr@gmail.com

Thanks to collaborators

Thanks to unknown colleagues

Thanks to the thousands who collect the data

All fish gone by 2048

Science 2006

Science 2006

Source: Time magazine, November 2006

A new consensus on stock status

www.ramlegacy.org

What is in a stock assessment?• History of abundance• History of catch, recruitment, fishing mortality• Estimates of reference points

2009 Paper

Stock Coverage

Open access https://www.pnas.org/content/117/4/2218.short

Trend in abundance and harvest rate

Stock Size

Fish

ing

Pres

sure

Fully Exploited

Overfishing

Under exploited

Overfished and

overfishing

Over fished

Yield lost from fishing too hard

Yield lost by overfishing (red) and underfishing (yellow)

From Hilborn and Costello 2017. Marine Policy. The potential for blue growth in marine fisheries yield, profit and abundance of fish in the ocean.

Abundance of stocks (expert opinion)

Summary of stock status

• Some places never overfished• Some were overfished and now recovering• Some continue to be overfished• Where we don’t have assessment data we generally

believe status is poor• Even in well managed places there are stocks in

poor condition due to ineffective management and natural variability

How are fisheries managed?

Research• landings data

• body size or age data

• surveys to monitor trends in abundance

• stock assessments

Management• objectives and fishery management plan

• regulations to limit fishing pressure

• capacity to adjust regulations and fishing

pressure

Enforcement• dockside monitoring /at-sea observers

• penalties and compliance

• protection of sensitive habitats

• discarding and by-catch measures

Socioeconomics• controls on access and entry

• transparency

• community involvement

• capacity-enhancing subsidies

Intensity of fisheries management

Overall intensity of fisheries management

What do we know about the rest of the world?

Where we don’t have assessments

Source: Global Assessment Database (ramlegacy.org)

www.ramlegacy.org

Abundance of stocks (expert opinion)

West coast Malaysia from TrawlBase

Rebuilding requires reducing fishing pressure

• This can be achieved in many ways– Hard TAC’s– Reducing fishing effort– Time area closures

• BUT you have to be able to enforce the regulations

• With VMS effort is easily monitored

Take away message

• Fisheries management works if applied• We have methods that work to

– Sustainably produce food from the ocean– Protect sensitive biodiversity

• The key to producing food and protecting biodiversity is to manage 100% of the ocean– Not to close 10% 20% or 30% of the ocean to

fishing

hilbornr@gmail.com

www.ramlegacy.org

https://rayhblog.wordpress.com/

https://sustainablefisheries-uw.org/

https://sites.uw.edu/trawlingbp/