Underwater Gelidium harvest off southwest Portugal - 1999

©João Mariano

Back to basicsGlobal shortage of bacteriological

and technical agars

Ricardo Melo + Rui Santos

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Nature 528: 171–172(December 10th, 2015)

“Microbiology’s most important reagent is in

short supply, with potential consequences for research,

public health and clinical labs around the world.”

“already pushed wholesale prices of agar to an all-time

high of around US$35–45 per kilogram — nearly triple

the price before scarcities began.”

by Ewen Callaway21/06/16

doi: 10.1038/528171a

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• Gelidium• Pterocladia/

Pterocladiella• Gelidiella• Gracilaria

Geography of commercial agarophytes

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Our ‘we told you so’ moment!• ISS XIX – 2007, Japan – Global Gelidium resource

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0

2000

4000

6000

8000

10000

12000

14000

16000

18000

20000

1980s 1990s 2000s

Decades

Land

ings

(t d

w)

South AfricaChileMexicoIndonesiaPortugalJapanSouth KoreaMoroccoSpain

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ISS XIX – 2007, Japan (cont.)

• Global Gelidium production in 3 preceding decades• ≈ 16 000 t (dw)

• Stable in South Africa, Chile, Mexico, South Korea

• Collapsed in Indonesia, Portugal, Japan, Spain

• But, how sustainable this level of production?• Maintained by Morocco’s very increased landings

• Representing 73% of world landings

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Our present objective is to:

• Compile available disseminated information• More and better data communication

• Identify bottlenecks and sustainability problems• Boost renewed attention to Gelidium resources

• Historical producer countries & others

• Disseminate a low cost stock assessment method• Based on harvest effort statistics

• Effective use of harvest logbooks

• Coaching of harvesters for sustainability

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Mean decadal landings (t ww)

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Global Gelidium resource

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• Has been in decline since 1960’s peak

• Dramatic drop in the 2010’s

• Production less than 50% of peak value

• Business as usual?

2010’s mean harvest ≈

pre-WW II situation *

* 1940

Not

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Other take-home ideas

• Steady increase of Morocco’s global share• From ≈20% in the 60’s up to ≈70% in the new century

• Global market virtually depends on sole supplier

• Fluctuations should have DISPROPORTIONATE effect

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Case study: Morocco (1)

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Case study: Morocco (2)

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Morocco: updated management

• Gelidium harvest• Interdiction: October 1st – June 30th

• Only beach cast harvest, no plucking, no night harvest• In 2010 limit was 5440 t in 2010, 6040 t in 2014

• Traceability system for Gelidium and agar commerce• Export licence regime for Gelidium and agar

• Restrictive export quotas enforced• Only 20% of Gelidium production• 80% must be processed in-country (Setexam, Kénitra)

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Santos, Cristo & Jesus 2003

• Describe stock assessment of Gelidium resource based on harvest effort information

• Low cost compared with common standing stock evaluations involving scientific diving

• Analysis of harvest effort data is highly informative• But:

• Information on sea conditions for each harvest day must be included to improve logbook data

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Gelidium corneum harvest in Portugal: yearly variation of harvest yield, total harvest effort, and seasonal CPUE (Santos et al. 2003)

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Training and coaching is a must

• Harvesters need to understand:• How logbook data will be used• The importance of providing accurate records

• Managers and scientists have to:• Better communicate with harvesters• Illustrate how the information obtained from harvest

effort data is to be used

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Gelidium corneum harvest in Portugal: yearly variation of standing stock, harvest yield, exploitation rate, and catchability (Santos et al. 2003)

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Data harvesting…

• A difficult task finding statistical data on agarophyte harvest!

• Also complicated assessing the quality of those data!

• On-line fisheries data from governmental and research institutions, trade associations, international experts

• Many individual researchers and friends were of great help

Previous reports by Santelices (1988), Santos and Duarte (1991), Melo et al. (1991), Melo (1998, 2002), McHugh (2003), and Santos et al. (2003) review harvest methods, fisheries statistics, cultivation attempts, and stock assessment of Gelidium species

21/06/16

Thank you!

João Mariano – Photography

www.joaomariano.com

Antonieta Pedroso – Illustration

pantonieta@gmail.com

G. corneum (=sesquipedale): commercial species in NE Atlantic