Nils Guse

Monitoring plastic ingestion by the northern fulmar Fulmarus glacialis in the North Sea

The abundance of plastics in stomachs of northern fulmars from the North Sea is used in the OSPAR Ecological Quality Objective (EcoQO) for marine litter. The preliminary EcoQO defines acceptable ecological quality as the situation where no more than 10% of fulmars exceed a critical level of 0.1 g of plastic in the stomach. During 2003-2007, 95% of 1295 fulmars sampled in the North Sea had plastic in the stomach (on average 35 pieces weighing 0.31 g) and the critical level of 0.1 g of plastic was exceeded by 58% of birds, with regional variations ranging from 48 to 78%. Long term data for the Netherlands since the 1980s show a decrease of industrial, but an increase of user plastics, with shipping and fisheries as the main sources. The EcoQO is now also used as an indicator for Good Environmental Status in the European Marine Strategy Framework Directive.

Perfluorinated compounds in red-throated divers from the German Baltic Sea: new findings from their distribution in 10 different tissues

Environmental context Perfluorinated compounds are commonly used chemicals that are detected globally in all environmental matrices. We investigated the extent of contamination by perfluorinated compounds in the red-throated diver, a marine predatory bird, and observed an unusual distribution of perfluorinated compounds in tissues. The data help us to better understand the behaviour of these contaminants in organisms. Abstract Twenty poly- and perfluorinated compounds (PFCs) were investigated in four red-throated divers (Gavia stellata) from the German Baltic Sea sampled in 2005. Concentrations of perfluoroalkyl sulfonates (PFSAs), perfluoroalkyl carboxylates (PFCAs), alkylated perfluoroalkyl sulfonamides, alkylated perfluoroalkyl sulfonamidoethanols and perfluorooctane sulfonamides were determined in blood, brain, fatty tissue, gall bladder, heart, kidney, liver, lung, muscle and spleen by high-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS). For quantification standard addition was applied. Twelve compounds were detected with average total PFC concentrations ranging from 42 ng g–1 in muscle to 220 ng g–1 in liver samples. Perfluorooctane sulfonate (PFOS) was the major compound in each of the 40 tissue samples. Except for brain, perfluoroundecanoate was the dominant PFCA. In brain samples preferential enrichment of long-chain PFSAs and PFCAs was observed. The total PFC body burden was estimated to 100 ± 39 µg. Multivariate statistical analyses supported the identification of the preferred accumulation ‘location’ of individual PFCs in the birds’ body.

Health status of seabirds and coastal birds found at the German North Sea coast

BackgroundSystematic pathological investigations to assess the health status of seabirds and coastal birds in Germany were performed. The investigation was conducted to obtain data on possible causes of decline in seabird and coastal bird populations.Methods48 individuals of 11 different species of seabirds and coastal birds were collected by the stranding network along the entire German North Sea coast from 1997 to 2008, including mainly waders such as Eurasian oystercatchers (Haematopus ostralegus) and red knots (Calidris canutus) as well as seabirds such as northern fulmars (Fulmaris glacialis) and common scoters (Melanitta nigra).For most birds (n = 31) found dead along the shore no obvious cause of death was evident, while 17 individuals were killed by collisions with lighthouses.ResultsOverall, the nutritional status of the investigated birds was very poor, and the body mass in most cases was significantly lower compared to masses of living birds caught during the same periods of the year. This is partly linked to chronic parasitic or bacterial infections in different organs or to septicaemia. In some cases infections with zoonotic tuberculosis caused by Mycobacterium spp. were found. Avian influenza was not found in any of the collected birds.ConclusionThe presented data contribute to the evaluation of the health status of birds in the German North Sea. Moreover, they present an important tool for the assessment of potential pathogens with an impact on the health status of seabirds and coastal birds.

Unchanging diet in a stable colony: contemporary and past diet composition of black-legged kittiwakes Rissa tridactyla at Helgoland, south-eastern North Sea

In contrast to the situation at the west coast of the North Sea, the breeding colony of black-legged kittiwakes Rissa tridactyla at Helgoland in the south-eastern North Sea did not exhibit severe declines since 1990 but instead numbers increased and only lately stabilised. Declines at the west coast of the North Sea were attributed to a lower abundance and lower quality of the key prey, sandeels. We hypothesised that kittiwakes at Helgoland do not rely as heavily on sandeels as their conspecifics. We analysed stomach contents of nestlings and adults of 2001, 2002, 2004 and 2006. In concordance with earlier studies of the 1980s and 1990s, young whiting Merlangius merlangus was the most important prey species in 2001, 2002 and 2004. Clupeids and sandeels were consumed in lower proportions. While earlier studies suggested whiting to originate from fisheries discards, evidence now supports that kittiwakes prey upon whiting in areas of hydrographic fronts. No whiting was recovered in samples of 2006 and the proportion of fish prey was low. Main prey items were polychaete worms (Nereidae), which were presumably consumed as swarming Heteronereis stages. An observed strong rise in water temperature in summer 2006 might have influenced food availability of kittiwakes by inducing swarming of Nereidae. Overall, kittiwakes breeding on Helgoland showed a positive population trend for several decades while mainly feeding on whiting.