Preparing For Ocean Change


Preparing For Ocean Change
Preparing for Ocean Change
Jason Hall-Spencer, Professor of Marine Biology,
Plymouth University
NOC Association 5th Annual Meeting 30th March 2015
Satellite data show the large area
affected by modern heavy gear
types in the English Channel
Footprint of a) UK scallop dredgers and b) UK beam trawlers >15
m length (Campbell et al. 2014 Marine Policy). This excludes the
significant footprint of non-UK vessels and those that are <15 m
in length.
Towed gear alters the seabed;
scallops are resilient but many
long-lived organisms are not
Maerl beds take 1000s of years to form and are badly
damaged by scallop dredges
Molfese et al. (2014) highlights the recent rapid
decline in mean Trophic Level of English Channel
This cartoon from Pauly et al. 2008 could be modified for
UK waters to show how fishing keeps ecosystems in a
much altered state around the UK
War years
English Channel catch composition
Shellfish (e.g. scallops) now more
prevalent in Channel landings.
There were more big fish before
widespread use of heavy towed
Case study 1
Soffker et al. 2011
Technology that puts marine life at risk can be used to protect it
Demersal gear closures
that maximize habitat
protection and minimize
fisheries displacement
Case Study 2
Hall-Spencer et al. (2008) Nature
Lots of organisms benefit from increased
CO2 levels & out compete those that don’t
Consistent patterns of marine ecosystem
change: as CO2 levels increase biodiversity declines.
Rodolfo-Metalpa et al. (2011)
Nature Climate Change
Protect here as these
reefs will avoid corrosion
by ocean acidification
Jackson et al. (2014) ICES J Mar Sci
Corrosive water depth for 1995, 2020, 2040, 2060, 2080 and 2099.
Confirmed stony coral presence records and predicted reef extent
What increased our REF impact was using scientific
discovery as a platform for work with industry, NGOs
and government in negotiating solutions to problems.
Our work on fishing impacts and ocean acidification first
assembled evidence then followed-up with advocacy on
how damaging practices could be reduced to balance
environmental quality with ocean use.
Hall-Spencer JM et al. (2008) Volcanic carbon dioxide vents reveal
ecosystem effects of ocean acidification. Nature 454, 96-99.
Jackson EL et al. (2014) Future-proofing Marine Protected Area
networks for cold water coral reefs. ICES Journal of Marine Science
71, 2621-2629.
Molfese C et al. (2014) Overfishing and the replacement of demersal
finfish by shellfish: an example from the English Channel. PLoS ONE
9(7), e101506.
Rodolfo-Metalpa R et al. (2011) Coral and mollusc resistance to
ocean acidification adversely affected by warming. Nature Climate
Change 1, 308-312.
Söffker M et al. (2011) In situ observations of fish associated with
coral reefs off Ireland. Deep-Sea Research Part 1 58, 818-825.