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BIRD EGGS as indicator for local pollution and trend analysis. Peter H. Becker Institut für Vogelforschung „Vogelwarte Helgoland“ Wilhelmshaven. Σ PCB ( μg/g Fettgewicht). Becker & Bruhn 2003. Species. Dose-dependent response: Seabirds indicate the contamination
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BIRD EGGS as indicator for local pollution and trend analysis Peter H. Becker Institut für Vogelforschung „Vogelwarte Helgoland“ Wilhelmshaven
Σ PCB (μg/g Fettgewicht) Becker & Bruhn 2003 Species
Dose-dependent response: Seabirds indicate the contamination of their prey and of the marine environment Seabirds at the top of the food web: BIOINDICATORS
Mercury PCB concentration in Common Tern eggs (ng·g-1 fresh weight) Annual load Elbe (kg· year-1) HCB Becker et al. (1991)
Herring, muscle Guillemot, egg Year ΣDDT (mg/kg fat weight) in Guillemots (eggs) and herring (muscle) from the Baltic Sea (Bignert et al. 1995)
Seabirds integrate the environmental situation across sea areas Common Tern: Radius of foraging flights in the breeding season: 6.3 km Peter H. Becker
Courtship Feeding in the Common Tern
Bird Eggs as Matrix for Monitoring Chemicals: ADVANTAGES • originate from a defined area and year • reflect the contamination of breeding females • (healthy and reproductive part of the population) • being restricted to the breeding season, the seasonal variation • in chemical‘s levels is reduced • not necessary to kill adults • sampling takes little time • easy to handle • consistent composition compared with tissues • high lipid content (accumulation of lipophilous persistent compounds) • during the egg and early chick stage birds react sensitively to • toxic chemicals • relationships between contaminants, eggshell quality and • hatching success can be studied • controlled experiments in the laboratory are possible
Bird Eggs as Matrix for Monitoring Chemicals: DISADVANTAGES • representative of only a part of the population and the year • some heavy metals are not accumulated in the egg (cadmium, lead)
______________________________________ Environmental Chemicals in Seabird Eggs analyzed in TMAP___________________________________________________ Industrial Chemicals Mercury catalyst, seed disinfection; banned in 1982 HCB byproduct OC-production fungicide, banned in 1980 PCB soft maker, in transformers, condensers, (62 - incl. coplanar - hydraulic oil; banned in 1989 congeners) Insecticides DDTand metabolites (p,p’-) banned in 1972 HCH-Isomeres(-, -, -HCH) technical HCH: banned in 1974 Chlordane (Chlordane, Nonachlor)banned in 1988 ____________________________________________________________________
Contaminants in Seabirds 10 eggs per site and species, 1 egg per clutch TMAP for monitoring the Wadden Sea
Geographic variation: Intersite differences TMAP: Results
Quecksilber Σ PCB Spatial Variation Common Tern 2002 HCB Konzentration (ng/g FG) Σ DDT North Sea Σ HCH Area Gebiet
Spatial Variation Oystercatcher 2002 concentration (ng/g FW) North Sea Area Gebiet
Year 2005 Common Tern Oystercatcher from annual report 2005 Peter H. Becker
Discriminant analysis of 62 PCB congeners Becker et al. (1998) Major components: PCB congeners 138,153,160,180,170,128
Temporal variation: 1981 - 2003 TMAP: Results
Trend Mercury 1981 - 2003 1981 85 1990 95 2000 YEAR
Trend PCBs 1981 - 2003 1981 85 1990 95 2000 YEAR
Mercury 2001 03 05 2001 03 05 YEAR from annual report 2005 Peter H. Becker
Oystercatcher Common Tern Trischen HCB ΣHCH 2001 03 05 2001 03 05 YEAR from annual report 2005
2001 -2005: 102 trendsstudied: 60 significant 48 (= 80 %) negative trends 12 (= 20 %) positive trends from annual report 2005 Peter H. Becker
Variation in PCB levels • Temporal variation (year) • Spatial variation (site) • Interspecific variation (species) Peter H. Becker
Conclusions and Future • Continue to measure contaminants • in bird eggs in the Wadden Sea in order to • - distinguish short-term fluctuations • from long-term trends • - to keep the hot spots under careful observation • Adapt the monitoring by • - an additional sampling site at the Rhine delta • - including „new“ toxic substances • Intensify policies • - for reduction of application and inputs of • hazardous xenobiotics TMAP
Conclusions and Future • EcoQOs Concentrations (ng/g) should not exceed: Mercury PCBs DDTs HCB HCHs _____________________________________ CT 200 20 10 2 2 OC 100 20 10 2 2 or values measured at southwestern Norway or Shetlands (ICES 2004) TMAP
Why sampling and chemical analysis on an annual basis ? • Logistical reasons: continuity in - staff - organization of sampling - availability of analytics is important to run the monitoring successfully. • Time trend analyses: Lacking years cause lower statistical power and hamper the function of the parameter as „early warning system“ Why the „one lab“ approach ? • Better compariability of results • No intercalibration needed Eggs DK data data 1 Lab Terramare Eggs SH Eggs NL data data Eggs NS
Contaminants inSeabirds: No. of sites in future ? 10 eggs per site and species, 1 egg per clutch TMAP for monitoring the Wadden Sea
Conclusions and Future • EcoQOs • Make use of birds as sensitive indicators: • Monitoring reproductive success as • early warning system TMAP