Hopes and expectations: the conceptual course of future for marine ecosystems and fishery Latvian Institute of Aquatic Ecology Latvian Fish Resources Agency UL Institute of Biology UL Faculty of Biology
Jan 19, 2016
Hopes and expectations: theconceptual course of future for marine ecosystems and fishery
Latvian Institute of Aquatic EcologyLatvian Fish Resources Agency
UL Institute of BiologyUL Faculty of Biology
Expected outcomes of WP work
• Improved knowledge on possible processes;• Participation in constructing environmental
legislation;• Recommendations for management and
adaptation strategies.
Gulf of Riga – future scene
Gulf of Riga – ecosystem projections
Winters without ice cover - • Earlier development of plankton communities,
higher biomassShift from Achnantes taeniata to Thalassiosira
baltica, Chaetoceros spp., Melosira nummuloides
• Shift in breeding time of benthic species, mostly amphipods
Gulf of Riga – ecosystem projectionsSprings with faster
stratification –• Dominance of
dinoflagellates or ...nothing special;
• Higher share of small size fraction in zooplankton.
0
4000
8000
12000
mg/
m3
0
10
20
30
40
119. st.
0
4000
8000
12000
mg/
m3
0
10
20
30
40165. st.
30.0
1.24
.02.
14.0
3.29
.03.
11.0
4.27
.04.
9.05
.18
.05.
31.0
5.
30.0
1.25
.02.
14.0
3.29
.03.
11.0
4.24
.04.
9.05
.18
.05.
30.0
5.
C yanophyceae
D iatom ophyceae
D inophyceae
Cryptophyceae
Chlorophyceae
Pârçjâs
H lorofils a
16.0
6.27
.06.
14.0
6.27
.06.
17.0
7.25
.07.
16.0
7.25
.07.
10.0
8.7.
08.
29.0
8.29
.08.
6.09
.28
.09.
4.09
.28
.09.
15.1
0.15
.10.
8.11
.8.
11.
27.1
1.5.
12.
27.1
1.5.
12.
18.1
2.19
.12.
Gulf of Riga – ecosystem projectionsWarmer summers: two options
Increased wind intensity:• Frequent upwellings,
productive coastal areas;• Reduced cyanobacterial
blooms.
Calm weather dominating:
Gulf of Riga – ecosystem projections
• Zooplankton Acartia bifilosa, Limnocalanus macrurus,
Evadne nordmanni, Pleopsis polyphemoides Daphnia spp., Cyclops spp.
• Macrozoobenthos Gammarus sp., Bathyporeia pilosa, Marenzelleria viridis, Macoma baltica
• Phytobenthos ???
Gulf of Riga - fisheries• Gulf of Riga
herring – growth expected and forecasted, still – spawning stock biomass hardly above the mean;
• Reason – high fishing mortality, low recruitment.
0
20000
40000
60000
80000
100000
120000
140000
1977
1980
1983
1986
1989
1992
1995
1998
2001
2004
2007
Nār
sta
bar
a b
iom
asa,
t
0
1000
2000
3000
4000
5000
6000
7000
8000
9000
1998 1999 2000 2001 2002 2003 2004 2005 2006 2007
paaudze
milj
on
i
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
The Baltic Sea – ecosystem projections in conditions of reduced salinity and higher
temperature• Species structures
gradually similar to the Gulf of Riga;
• Coastal areas – level of human activities significant: nutrient loads;
• Further reduction of inhabited bottoms.
The Baltic Sea - fisheries
• The Eastern Baltic cod – fishing mortality as a key factor
1980 2000 2020 2040 2060 2080 2100
020
040
060
0
F = 1.08
Year
SS
B (
thou
sand
tons
)
w ithout climate changew ith climate change
1980 2000 2020 2040 2060 2080 21000
200
500
F = 0.7
Year
SS
B (
thou
sand
tons
)
1980 2000 2020 2040 2060 2080 2100
040
010
00
F = 0.3
Year
SS
B (
thou
sand
tons
)
1980 2000 2020 2040 2060 2080 2100
010
0020
00
F = 0
Year
SS
B (
thou
sand
tons
)
Conclusions
• Coastal zone would strengthen its position as a key area in the aspect of productivity and biodiversity;
• The Gulf of Riga and the Baltic Sea would continue being attractive for invasive species;
• The climate change would intensify or mask the impact of key factor - human activities.
Recommendations:• elaborate and implement the load reduction activities as soon as
possible in all related areas (agriculture, water resources management etc.);
• create zonation of the coastal underwater areas with various level of protection according to the functional importance of the site;
• perform regular observations of marine environment and provide model calculations of processes, based on the observations for flexible management decisions;
• reduce the fishing mortality via exclusion of illegal fishing;
• follow the international regulations preventing the distribution of non-native species.
Thank you for your attention!