north sea - This Side Of paradise
Transcription
north sea - This Side Of paradise
De Noordzee: historische veranderingen in een voedselrijke shelfzee Kees Camphuysen Royal Netherlands Institute for Sea Research, Texel North Seabirds Norway 59N NORTH SEA 58N Migratory birds divers, Northern Gannet, seaduck, skuas, gulls, terns 57N 56N Coastal wintering birds divers, grebes, seaduck, Larusgulls Nursery areas Common Guillemot 55N 54N 53N Britain Pelagic wintering birds Black-legged Kittiwake, auks 52N Southern North Sea The Netherlands 51N Belgium Cross-road, wintering area 2W 0 2E 4E 6E Divers Grebes Fulmars Gannets Cormorants Sea-duck Skuas Gulls Terns Auks cliff-nesting species Seabird colonies max colony size Atlantic Puffin 100000 Manx Shearwater 100000 Northern Gannet 70000 Northern Fulmar 45000 Guillemot 40000 Lesser Bl-b Gull 30000 Kittiwake 30000 Herring Gull 18000 Sandwich Tern 8000 Arctic Tern 3000 Common Tern 1500 Shag 1000 Cormorant 500 Black Guillemot 150 Little Tern 110 After: Coulson 2002 (modified) range 250 450 450 450 100 100 100 60 25 15 15 14 13 10 8 Divers Grebes Fulmars Gannets Cormorants Sea-duck Skuas Gulls Terns Auks tundra nesting birds Divers Grebes Fulmars Gannets Cormorants Sea-duck Skuas Gulls Terns Auks ground nesting species Jan van Gent Morus bassanus CJ Camphuysen Vaste verspreidingspatronen......of een veranderend beeld? 300000 UK populatie Jan van Gent 200000 Jan van Gent Morus bassanus 250000 150000 100000 50000 0 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 Wanless 60000 et al. 2005 Brit Birds 98: 280-294 Bass Rock 50000 40000 30000 20000 10000 0 1805 1855 1905 1955 2005 Jan van Gent Morus bassanus CJ Camphuysen N Northern Gannet Bass Rock colony (Scotland) satellite tag data N 100 km 100 km GPS logger data <1750 <1800 1800 1825 1850 1875 1900 1925 1950 1975 2000 Northern Fulmar Fulmarus glacialis ocean inflow Norwegian deep central North Sea fronts river run-off area Southern Bight German Bight Coastal front Tidal front Common Guillemot Chicks and moulting adults penetrate deeper southwards Recent surveys revealed higher late summer auk densities and lower chick percentages 1987-88 July 18% chicks 2006 July 7% chicks Norway 59N NORTH SEA 58N 57N 56N Zeekoet - Common Guillemot 55N 54.0N 54N L5-B L5-C PE-L7-PB L8-P L8-AL8-H 53.5N 53N 53.0N 1 2 3-5 6-10 11-25 26-50 51-100 101-1000 3.0E 52N July 2006 4.0E Britain The Netherlands 5.0E 51N Belgium Chick rearing occurs in Dutch nurseries, off the Wadden Sea islands 2W 0 2E 4E 6E juli 2006 survey Zeekoet Friese Front, SC41 54N 30m NCP Terschelling FRONT NCP Ameland Vlieland route 30m Texel 53N 3E 4E 5E 6E even while nesting in Scotland Chick rearing occurs in Dutch nurseries, off the Wadden Sea islands Common Guillemot abundance (July) Kittiwakes breeding in The Netherlands! 59N First confirmed breeding 2000 58N Norway Camphuysen C.J. & F. de Vreeze 2005. De Drieteenmeeuw Rissa tridactyla als broedvogel in Nederland. Limosa 78(2): 65-74. NORTH SEA >2 colonies 2005 >6 colonies 2006 57N 56N 55N 54N 53N Britain 52N The Netherlands 51N Belgium 2W 0 2E 4E 6E Looking at seabirds Beached bird surveys Noordse Stormvogel Fulmarus glacialis (donkere fase) Beached bird surveys Beached bird surveys Zeekoet Uria aalge Beached bird surveys Tricolor olie-incident 3.0 2.5 2.0 1.5 Common Eider, 1975/76-2009/10 100% y = -0.0595x + 0.4309 R² = 0.7321 Beached bird surveys Noordzee Waddenzee 1.0 0.5 50% 0.0 -0.5 -1.0 -1.5 -2.0 y = -0.072x + 0.2164 R² = 0.6418 -2.5 0% -3.0 1975/76 1977/78 1979/80 1981/82 1983/84 1985/86 1987/88 1989/90 1991/92 1993/94 1995/96 1997/98 1999/00 2001/02 2003/04 2005/06 2007/08 2009/10 3.0 2.5 y = -0.0368x + 1.274 R² = 0.5757 Common Guillemot, 1975/76-2009/10 100% Eidereend Somateria mollissima 2.0 1.5 1.0 0.5 50% 0.0 -0.5 -1.0 -1.5 -2.0 y = -0.048x + 1.1715 R² = 0.7146 -2.5 -3.0 0% 1975/76 1977/78 1979/80 1981/82 1983/84 1985/86 1987/88 1989/90 1991/92 1993/94 1995/96 1997/98 1999/00 2001/02 2003/04 2005/06 2007/08 2009/10 Zeekoet Uria aalge A long-term decline in oil-rates indicative of a decline in marine oil pollution Onderzoek: CJ Camphuysen, NIOZ MF Leopold, IMARES Onderzoek: JA v Franeker, IMARES Noordse Stormvogel Fulmarus glacialis Onderzoek: JA v Franeker, IMARES Noordse Stormvogel Fulmarus glacialis Onderzoek: JA v Franeker, IMARES Jan van Gent Morus bassanus Aalscholver Phalacrocorax carbo Grote Mantelmeeuw Larus marinus Seawatching © Bart Vastenhouw Seawatching IJmuiden Camperduin off N America, MayAug Chili & Falklands, breeding, Nov-Apr Atlantic Margin, Jul-Oct Grauwe Pijlstormvogel Puffinus griseus Seawatching 0.35 7 Noordse Stormvogel 6 5 0.25 4 0.2 3 0.15 2 0.1 1 0.05 0 0 J F M A M Grauwe Pijlstormvogel 0.3 J J A S O N J D F M A M J J A S O N D J A S O N D 0.2 Noordse Pijlstormvogel 98.600 uren observatie 120.450 Noordse Stormvogel 0.15 27 7.600 Grauwe Pijl 84 4.405 Noordse Pijl 1 0.1 0.05 0 J Informatie: F M A M J Nederlandse Zeevogelgroep (Club van Zeetrekwaarnemers) www.trektellen.nl Seawatching 60 25 Duikers Fuut 50 20 40 15 30 10 20 5 10 0 0 J F M A M J J A S O N J D F M A M J J A S O N D S O N D 0.2 Roodhalsfuut 98.600 uren observatie 0.15 482.400 duikers 53 758.600 Fuut 84 9.025 Roodhalsfuten 0.1 0.05 1 0 J Informatie: F M A M J J A Nederlandse Zeevogelgroep (Club van Zeetrekwaarnemers) www.trektellen.nl -6 -11 1 jan - 7 jan 8 jan - 14 jan 15 jan - 21 jan 22 jan - 28 jan 29 jan - 4 feb 5 feb - 11 feb 12 feb - 18 feb 19 feb - 25 feb 26 feb - 4 mrt 5 mrt - 11 mrt 12 mrt - 18 mrt 19 mrt - 25 mrt 26 mrt - 1 apr 2 apr - 8 apr 9 apr - 15 apr 16 apr - 22 apr 23 apr - 29 apr 30 apr - 6 mei 7 mei - 13 mei 14 mei - 20 mei 21 mei - 27 mei 28 mei - 3 jun 4 jun - 10 jun 11 jun - 17 jun 18 jun - 24 jun 25 jun - 1 jul 2 jul - 8 jul 9 jul - 15 jul 16 jul - 22 jul 23 jul - 29 jul 30 jul - 5 aug 6 aug - 12 aug 13 aug - 19 aug 20 aug - 26 aug 27 aug - 2 sep 3 sep - 9 sep 10 sep - 16 sep 17 sep - 23 sep 24 sep - 30 sep 1 okt - 7 okt 8 okt - 14 okt 15 okt - 21 okt 22 okt - 28 okt 29 okt - 4 nov 5 nov - 11 nov 12 nov - 18 nov 19 nov - 25 nov 26 nov - 2 dec 3 dec - 9 dec 10 dec - 16 dec 17 dec - 23 dec 24 dec - 31 dec Aantal Jan van Genten per waarnemingsuur 9 Seawatching naar Noord 4 -1 juveniel (1 jaar) onvolwassen (2-4 jaar) volwassen (>5 jaar) naar Zuid -16 Seabirds at sea Seabirds at sea ESAS database observer effort in summer (km² surveyed) ESAS database observer effort in winter (km² surveyed) 60N 60N 59N 59N 58N 58N 57N 57N 56N 56N 55N 55N 54N 54N 53N 53N E ffor t (km ²) 52N E ffor t (km ²) 0.01 - 4.99 52N 0.01 - 4.99 5.00 - 9.99 5.00 - 9.99 10.00 - 24.99 51N 25.00 - 49.99 10.00 - 24.99 51N 25.00 - 49.99 50.00 + 5W 4W 3W 2W 1W 0 1E 2E 3E 4E 5E 6E 7E 8E 9E 10E 50.00 + 11E 5W Waarnemingsinspanning ESAS database 4W 3W 2W 1W 0 1E 2E 3E 4E 5E 6E 7E 8E 9E 10E 11E Roodkeelduiker, winter Kleine Alk, winter Little Auk distribution in winter, n per km² (ESAS 4.1) Diver distribution in winter, n per km² (ESAS 4.1) 60N 60N 59N 59N 58N 58N 57N 57N 56N 56N 55N 55N 54N 54N D ichtheid (n/km ²) 53N D ichtheid (n/km ²) 53N B lanco = geen B lanco = geen 0.01 - 0.09 0.01 - 0.09 fronts 52N 52N 0.10 - 0.49 0.10 - 0.49 0.50 - 0.99 0.50 - 0.99 51N 1.00 - 2.49 51N 1.00 - 2.49 2.50 + 2.50 + 5W 4W 3W 2W 1W 0 1E 2E 3E 4E 5E 6E 7E 8E 9E 10E 11E 5W 4W 3W 2W 1W 0 1E 2E 3E 4E 5E 6E 7E 8E 9E 10E 11E Zeekoet, zomer Zeekoet, winter Guillemots in winter, n per km² (ESAS 4.1) Guillemots in summer, n per km² (ESAS 4.1) 60N 60N 59N 59N 58N 58N 57N 57N 56N 56N 55N 55N 54N 54N D ichtheid (n/km ²) 53N D ichtheid (n/km ²) 53N B lanco = geen B lanco = geen 0.01 - 0.09 0.01 - 0.09 52N 52N 0.10 - 0.49 0.10 - 0.49 0.50 - 0.99 0.50 - 0.99 51N 1.00 - 2.49 51N 1.00 - 2.49 2.50 + 2.50 + 5W 4W 3W 2W 1W 0 1E 2E 3E 4E 5E 6E 7E 8E 9E 10E 11E 5W 4W 3W 2W 1W 0 1E 2E 3E 4E 5E 6E 7E 8E 9E 10E 11E Papegaaiduiker, zomer Alk, zomer Puffin in summer, n per km² (ESAS 4.1) Razorbills in summer, n per km² (ESAS 4.1) 60N 60N 59N 59N 58N 58N 57N 57N 56N 56N 55N 55N 54N 54N D ichtheid (n/km ²) 53N D ichtheid (n/km ²) 53N B lanco = geen B lanco = geen 0.01 - 0.09 52N 0.10 - 0.49 0.01 - 0.09 52N 0.10 - 0.49 0.50 - 0.99 51N 1.00 - 2.49 0.50 - 0.99 51N 1.00 - 2.49 2.50 + 5W 4W 3W 2W 1W 0 1E 2E 3E 4E 5E 6E 7E 8E 9E 10E 2.50 + 11E 5W 4W 3W 2W 1W 0 1E 2E 3E 4E 5E 6E 7E 8E 9E 10E 11E Oil pollution sensitivity maps Conservation value maps North Sea cetaceans Harbour Porpoise Phocoena phocoena Bruinvis White-beaked Dolphin Lagenorhynchus albirostris Witsnuitdolfijn In Nederland aangetroffen walvisachtigen Grijze Walvis Blauwe Vinvis Gewone Vinvis Noordse Vinvis Dwergvinvis Bultrug Potvis Dwergpotvis Narwal Beloega Dolfijn van Cuvier Butskop Spitssnuitdolfijn van Gray Gewone Spitssnuitdolfijn Spitssnuitdolfijn van De Blainville Orka Zwarte Zwaardwalvis Griend Snaveldolfijn Tuimelaar Gestreepte Dolfijn Gewone Dolfijn Witsnuitdolfijn Witflankdolfijn Grijze Dolfijn Bruinvis Bultrug Dwergvinvis Griend Grijze Dolfijn Orka Witsnuitdolfijn Dwergvinvis Witflankdolfijn Tuimelaar Bruinvis Tekeningen Frits-Jan Maas Gewone Dolfijn Camphuysen & Peet 2006. Walvissen en dolfijnen in de Noordzee. Walvisstrandingen © CJ Camphuysen Noord-oost Atlantische Oceaan Diepe oceaan Shelfzee DOGGER Land <200m 200-600m 1000-3500m Lowe P.R. 1913. Our common sea-birds. Country life, C. Scribner's sons London, New York diep-duikers Butskop Potvis spitssnuitdolfijnen Land <200m 200-600m 1000-3500m 16 14 12 10 8 6 4 2 0 Butskop (12) spitssnuitdolfijnen (21) Potvis (20) DOGGER 1900 1910 1920 1930 1940 Lowe P.R. 1913. Our common sea-birds. Country life, C. 1950 Scribner's 1960 1970 1980 1990 2000 sons London, New York vinvissen Gewone Vinvis Noordse Vinvis 16 14 12 10 8 6 4 2 0 Dwergvinvis Dwergvinvis (28) Noordse Vinvis (3) Gewone Vinvis (16) DOGGER Land <200m 200-600m 1000-3500m 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 Lowe P.R. 1913. Our common sea-birds. Country life, C. Scribner's sons London, New York Blackfish” “ Orka 6 Griend (14) 5 Orka (22) 4 3 2 Wereldverspreiding 1 0 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 Griend Gematigd, shelfranden DOGGER Land <200m 200-600m 1000-3500m Lowe P.R. 1913. Our common sea-birds. Country life, C. Scribner's sons London, New York 120 Witflankdolfijn (11) Witsnuitdolfijn (220) 100 Gewone Dolfijn (86) Tuimelaar (391) 80 60 dolfijnen ?? 40 Witflankdolfijn 20 0 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 Gematigd 6 Griend (14) 5 Orka (22) Koud water Witsnuitdolfijn 4 3 2 1 Tuimelaar 0 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 DOGGER Warm water Gewone Dolfijn Lokaal, kust Land <200m 200-600m 1000-3500m Lowe P.R. 1913. Our common sea-birds. Country life, C. Scribner's sons London, New York Walvisstrandingen in Nederland ??? 100% 90% Witflankdolfijn (11) 80% Witsnuitdolfijn (220) Gewone Dolfijn (86) 70% Tuimelaar (391) 60% Griend (14) Orka (22) 50% Butskop (12) 40% spitssnuitdolfijnen (21) Potvis (20) 30% Dwergvinvis (28) 20% Noordse Vinvis (3) Gewone Vinvis (16) 10% 0% 1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000 Seawatchers 1968-2006 Ship-based surveys < 1925-2006 1978-2006 Whale strandings data Beached bird surveys Southern North Sea Observing coastal marine life: changing fortunes due to changing opportunities 1965-2006 Coastal population of Harbour Porpoise Phocoena phocoena and Bottlenose Dolphin Tursiops truncatus in The Netherlands abundant common ?? 41% per annum increase coastal sightings scarce Harbour Porpoise Bottlenose Dolphin none 1900 Southern North Sea Cetaceans 1920 1940 1960 1980 2000 Reconstruction based on anecdotal reports, systematic sightings and strandings reports 1900-1005 Marsdiep herring fisheries (catch), 1933-1940 1 1933 1934 1935 1936 1937 1938 1939 1 10,700,000 kg 14,800,000 kg 12,500,000 kg 15,100,000 kg 7,400,000 kg 1,200,000 kg 10,000 kg Jaarberichten over de visserij, 1933-1939 Closure of Zuiderzee often mentioned to explain why dolphins and porpoises disappeared collapse of local herring stock The Netherlands Disappearance of spring spawning (Zuiderzee-) herring Incid. Number of animals reported 700 CvZ CvZ (n per hour) Camphuysen C.J. 2004. The return of the harbour porpoise (Phocoena phocoena) in Dutch coastal waters. Lutra 47(2): 113-122. 0.4 0.35 600 0.3 500 0.25 400 0.2 300 0.15 200 0.1 100 0.05 0 0 1970 1972 1974 1976 1978 1980 1982 1984 1986 1988 1990 1992 1994 1996 1998 2000 2002 2004 Year Southern North Sea Abrupt changes in coastal marine life (1) return of the harbour porpoise Effort corrected (n per hour) Harbour Porpoises in Dutch coastal waters, 1970-2004 800 Afsluitdijk 20 18 Bottlenose Dolphin Tuimelaar 16 White-beaked Dolphin Witsnuitdolfijn 14 12 10 8 6 4 2 0 1915 1919 1923 1927 1931 1935 1939 1943 1947 1951 1955 1959 1963 1967 1972 1976 1980 1984 1988 1992 1996 2000 2004 Documented strandings of Bottlenose Dolphins and White-beaked Dolphins in The Netherlands, 1900-2005 Southern North Sea Changing fauna: dolphins Camphuysen & Peet 2006. Walvissen in de Zuidelijke Noordzee. Fonteijn Uitgeverij, Haarlem, Stichting De Noordzee, Utrecht Sightings of large groups of Bottlenose Dolphins after an absence of 45 years in the Marsdiep area ca. 100 ca. 54 Southern North Sea Changing fauna: dolphins 12 August 2004 9 September 2004 Camphuysen & Peet 2006. Walvissen in de Zuidelijke Noordzee. Fonteijn Uitgeverij, Haarlem, Stichting De Noordzee, Utrecht Southern North Sea Meij S.E.T. van der & C.J. Camphuysen 2006. Distribution and diversity of whales and dolphins (Cetacea) in the Southern North Sea: 1970-2005. Lutra 49(1). Abrupt changes in coastal marine life (2) large baleen whales, foraging pelagic seabirds Foto: Jan Wierda Camphuysen C.J. 2007. Foraging humpback whale (Megaptera novaeangliae) in the Marsdiep area (Wadden Sea), May 2007 and a review of sightings and strandings in the southern North Sea, 2003-2007. Lutra 50: 31-42. ansichtkaart 2007 Brasserie Samsam – Texel 4 Texelse bieren van ‘t vat Lunch – Borreluur - Diner Razende Bol, Texel, dec 2012 Foto Twitter / @wiewatwaarwendy Some 40 odd years ago • “Silent Spring” • Torrey Canyon oil spill • Club of Rome report Rachel Carson 1962. Silent Spring Meadows H.D.et al. 1972. The Limits to Growth. A Report to The Club of Rome (old farts always start looking back) Some 40 odd years ago • Chemical pollution greater rivers and coastal zone • Mass mortality of seabirds Wadden Sea • Reductions in seal populations / fertility • High levels of chronic oil pollution • Cetaceans in Dutch coastal waters disappear Koeman J.H. et al. 1969. Chlorinated Biphenyls in fish, mussels and birds from the River Rhine and the Netherlands Coastal Area. Nature 221 (5186): 1126-1128. Philippona J. 1965. Tegenwoordig is het strand zonder sterns. Het Vogeljaar 13: 533-534. Reijnders P.J.H. 1986. Reproductive failure in common seals feeding on fish from polluted coastal waters. Nature (London) 324: 456-457. (old farts always start looking back) Common Eider Common Eider Somateria mollissma 10000 Somateria mollissima 9000 pesticides 8000 2.5-5% per annum decline since 1990 7000 6000 5000 4000 3000 2000 1000 * data Camphuysen 1996 & SOVON Monitoring, Nijmegen 0 1900 1906 1912 1918 1924 1930 1936 1942 1948 1954 1960 1966 1972 1978 1984 1990 1996 2002 Harbour sea Phoca vitulina and Grey Seal Halichoerus grypus 18000 1600 16000 1400 14000 1200 12000 1000 10000 virus 800 8000 6000 end of premium 600 calculated data based on hunting statistics virus pesticides 400 4000 Harbour Seal 2000 200 Grey Seal 0 1900 1910 1920 1930 1940 1950 1960 1970 * 1980 Southern North Sea Common Eiders, seals (Eidereend, zeehonden) 0 1990 2000 Harbour & Grey Seals Phoca vitulina, Halichoerus grypus data Peter Reijnders (IMARES, Texel), pers. comm. * ( re-)colonisations Herring Gull Larus argentatus 100000 declining resources 80000 conservation Herring Gull Larus argentatus 60000 egg-collecting, culls, poisoning 40000 20000 conservation 0 1900 1906 1912 1918 1924 1930 1936 1942 1948 1954 1960 1966 1972 1978 1984 1990 1996 2002 data Spaans 1998 & SOVON Monitoring, Nijmegen Lesser Black-backed Gull Larus fuscus 100000 declining resources 80000 Lesser Black-b. Gull Larus fuscus 60000 40000 beamtrawler introduction 20000 * 0 1900 1906 1912 1918 1924 1930 1936 1942 1948 1954 1960 1966 1972 1978 1984 1990 1996 2002 Southern North Sea data Spaans 1998 & SOVON Monitoring, Nijmegen * colonisation Herring and Lesser Black-backed Gulls (Zilvermeeuw & Kleine Mantelmeeuw) Changing fortunes Sandwich Tern Sterna sandvicensis Sandwich Tern Sterna sandvicensis The Netherlands & Belgium combined 50000 egg collecting 40000 recovery 30000 20000 feather trade, egging protection pesticides 1960s partial recovery 10000 Zeebrugge Belgium * 0 1900 1905 1910 1915 1920 1925 1930 1935 1940 Southern North Sea Breeding birds: Sandwich Tern 1945 1950 1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 data Stienen 2006 Stienen E.W.M. 2006. Living with gulls: trading off food and predation in the Sandwich Tern Sterna sanvicensis. Ph-D. thesis Univ. Groningen, Groningen * colonisation Great Cormorant Common Eider (1906) Mediterranean Gull (1980) Little Gull (1942) Black-headed Gull Common Gull (1908) Lesser Black-backed Gull (1932) Herring Gull Yellow-legged Gull (1985) Great Black-backed Gull (1994) Black-legged Kittiwake (2000) Gull-billed Tern Sandwich Tern Common Tern Arctic Tern Little Tern Grey Seal (1980) Harbour Porpoise Bottlenose Dolphin White-beaked Dolphin Common Dolphin < 1900 depressed extinct 1900 depressed 1950 depressed colonising common extinct common common common few common increasing increasing common common common common common few declining declining few declining few abundant abundant few common extinct common common? ? ? common common? declining declining frequent Southern North Sea Breeding birds, marine mammals, population developments 20th century 2000 abundant common colonising few abundant abundant abundant abundant colonising colonising colonising extinct common common few common colonising increasing extinct frequent A changing landscape Norway 59N NORTH SEA 58N With a country partly below sea level, violent storms could cause serious floodings. Low-land people had always been building dikes for safety and to avoid property loss, but some particularly heavy storms in the 19th and 20th centuries triggered the construction of a dam closing the Zuiderzee (1932) and a plan to dam the entire estuarine area in the south (1955-1990). 57N 56N 55N 54N 53N Britain 52N The Netherlands 51N Belgium 2W 0 2E 4E 6E A changing landscape A changing landscape A changing landscape Most nesting attempts of Little Gulls in The Netherlands take place in highly dynamic areas, in particular where the areas have just been altered by man. Little Gull Little Gull 70 Larus minutus Number of breeding pairs 60 50 elsewhere Friesland Lauwersmeer Wadden Sea Lauwersmeer (reclamation) habitat deterioration • vegetation succession 40 30 • grazing • Red Fox 20 10 0 1940 1943 1946 1949 1952 1955 1958 1961 1964 1967 1970 1973 1976 1979 1982 1985 1988 1991 1994 1997 Southern North Sea Habitat change: Little Gull population trends Koks B.J. 1998. The Little Gull Larus minutus as breeding bird in The Netherlands. Sula 12(4): 137-146. A changing landscape, changing opportunities Morris's British Birds 1891 Scanned by www.BirdCheck.co.uk scattered inland colonies, persecuted by fishermen and nature conservation bodies Great Cormorant Phalacrocorax carbo sinensis Southern North Sea Eerden M.R. van et al. 1998. Long-term changes in wetland area and composition in the Netherlands affecting the carrying capacity for wintering water birds. Ph.D.-thesis University of Groningen, Groningen. Great Cormorant, establishing a “marine” population, utilising a neglegted habitat A changing landscape, changing attitudes, changing opportunities Morris's British Birds 1891 Scanned by www.BirdCheck.co.uk scattered inland colonies, new breeding opportunities, some protection Great Cormorant Phalacrocorax carbo sinensis Southern North Sea Eerden M.R. van et al. 1998. Long-term changes in wetland area and composition in the Netherlands affecting the carrying capacity for wintering water birds. Ph.D.-thesis University of Groningen, Groningen. Great Cormorant, establishing a “marine” population, utilising a neglegted habitat A changing landscape, changing attitudes, changing opportunities Morris's British Birds 1891 Scanned by www.BirdCheck.co.uk scattered inland colonies, persecuted by fishermen and nature conservation bodies, lowest population ever Great Cormorant Phalacrocorax carbo sinensis Southern North Sea Eerden M.R. van et al. 1998. Long-term changes in wetland area and composition in the Netherlands affecting the carrying capacity for wintering water birds. Ph.D.-thesis University of Groningen, Groningen. Great Cormorant, establishing a “marine” population, utilising a neglegted habitat A changing landscape, changing attitudes, changing opportunities Morris's British Birds 1891 Scanned by www.BirdCheck.co.uk new breeding opportunities IJsselmeer colonised, protection Naardermeer, population recovery Great Cormorant Phalacrocorax carbo sinensis Southern North Sea Eerden M.R. van et al. 1998. Long-term changes in wetland area and composition in the Netherlands affecting the carrying capacity for wintering water birds. Ph.D.-thesis University of Groningen, Groningen. Great Cormorant, establishing a “marine” population, utilising a neglegted habitat A changing landscape, changing attitudes, changing opportunities Morris's British Birds 1891 Scanned by www.BirdCheck.co.uk rapid expansion IJsselmeer population, Voorne colonised, population explosion eutrophication IJsselmeer (rich feeding in turbid waters) Southern North Sea Great Cormorant Phalacrocorax carbo sinensis Eerden M.R. van et al. 1998. Long-term changes in wetland area and composition in the Netherlands affecting the carrying capacity for wintering water birds. Ph.D.-thesis University of Groningen, Groningen. Great Cormorant, establishing a “marine” population, utilising a neglegted habitat A changing landscape, changing attitudes, changing opportunities Morris's British Birds 1891 Scanned by www.BirdCheck.co.uk rapid expansion IJsselmeer population, Voorne colonised, population explosion eutrophication IJsselmeer (rich feeding in turbid waters) Southern North Sea Great Cormorant Phalacrocorax carbo sinensis Eerden M.R. van et al. 1998. Long-term changes in wetland area and composition in the Netherlands affecting the carrying capacity for wintering water birds. Ph.D.-thesis University of Groningen, Groningen. Great Cormorant, establishing a “marine” population, utilising a neglegted habitat A changing landscape, changing attitudes, changing opportunities Morris's British Birds 1891 Scanned by www.BirdCheck.co.uk distribution shift IJsselmeer population, Wadden Sea and coast colonised, population growth slowed down IJsselmeer cleaner and poorer; a shift to the north and to the coast Southern North Sea Great Cormorant Phalacrocorax carbo sinensis Eerden M.R. van et al. 1998. Long-term changes in wetland area and composition in the Netherlands affecting the carrying capacity for wintering water birds. Ph.D.-thesis University of Groningen, Groningen. Great Cormorant, establishing a “marine” population, utilising a neglegted habitat A changing landscape, changing attitudes, changing opportunities breeding population non-breeding birds Great Cormorant Phalacrocorax carbo sinensis Southern North Sea Eerden M.R. van et al. 1998. Long-term changes in wetland area and composition in the Netherlands affecting the carrying capacity for wintering water birds. Ph.D.-thesis University of Groningen, Groningen. Great Cormorant, establishing a “marine” population, utilising a neglegted habitat Breeding seabirds and changing resources Demographical data fecundity survival recruitment Lesser Black-backed Gull GPS time spent 53.8N 53.6N P r esence (h) None 0.1- 1 1-2 2-5 5 - 10 10 - 100 100 + Herring Gull GPS time spent LBBG 53.8N 53.6N 53.4N 53.4N 53.2N 53.2N 53.0N 53.0N 52.8N 52.8N 52.6N 52.6N 52.4N 52.4N 52.2N 52.2N 52.0N 52.0N 51.8N 51.8N 3.0E 3.5E 4.0E 2008-2013 4.5E 5.0E 5.5E P r esence (h) None 0.1- 1 1-2 2-5 5 - 10 10 - 100 100 + 3.0E HG 3.5E Foraging distribution (h) during breeding 4.0E 2013 4.5E 5.0E 5.5E Scavenging behind fishing vessels 87 A weekend effect A long term decline in fishing effort Towards more sustainable fisheries The overfishing paradox www.waarneming.nl ………………….a critique……. Veranderingen kunnen alleen gevolgd worden wanneer er gecorrigeerd kan worden voor verschillen in waarnemingsinspanning Thank you © CJ Camphuysen