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Seals in the Wadden Sea are easy to study and count when they are exposed at haulout sites. However, our knowledge of seal activity at sea is limited. Consequently, in spring and autumn of 2002 and 2003, we equipped 19 seals with a logger/PTT-combined system to record at 15-second intervals, swim speed and direction, dive depths, water temperature and water turbidity. After a predefined time, the devices were automatically released to be washed ashore, where they could be located by satellite signal or found by beach walkers. The stored data showed that the seals did not forage in the Wadden Sea, but travelled to specific in the North Sea where they foraged on benthic prey, usually for several days, before returning straight back to their sandbank. Animals almost always dived to the seabed during both commuting and foraging. However, the dive profile was more irregular in the Wadden Sea compared to the deeper North Sea where the diving pattern was very regular, particularly with respect to depth and duration. Seals in the Wadden Sea not only rested on land at their haulout spots but also in the water, sinking down to the seafloor where they lay motionless for around 7 minutes, surfacing only for a short period to breathe before sinking back again. In deeper water (over 10 metres deep), the seals rested for up to 50 minutes at the surface, apparently drifting and showing no diving activity.

The harbour porpoise () is a small cetacean species occurring both in the German North Sea and Baltic Sea. In the process of designating marine protected areas in the framework of the European Habitats Directive (NATURA 2000), the German Federal Agency of Nature Conservation (BfN) identified candidate areas to be eventually proposed as Sites of Community Importance (pSCI). To evaluate the importance of these sites for harbour porpoises, their distribution and density were studied by conducting aerial surveys in the sites from May 2002 to September 2003 (further surveys are ongoing). Densities in the study areas were compared between study years as well as between the selected areas. The relative importance of sites was assessed by taking into account the overall distribution of porpoises in German waters. Surveys followed the standard line-transect methodology for aerial surveys. Only summer flights in the period from May to August were used for further analysis since the coverage by flights in autumn and winter was very low due to unfavourable weather conditions. In the German North Sea, 338 sightings of porpoise groups (440 individuals in total) were recorded in the summer of 2002, and 656 sightings (812 individuals in total) in the summer of 2003. In the Baltic Sea, sighting numbers in the same period were much smaller: 50 sightings (110 individuals) in 2002 and 34 sightings (43 individuals) in 2003. The main results showed clear aggregations and high densities of porpoises in the areas off the North Friesian islands of Sylt and Amrum, where there are high concentrations of the species in the summer months, which is their reproduction period. There seems to be a sharp gradient of density running from north to south. The highest density in both years was found in the study area , followed by the . Lowest densities were calculated for . The mean density did not differ significantly between study years in the same area. Harbour porpoise distribution in the Baltic Sea showed higher densities in the western part, namely in the and , and in the eastern part close to the border of Poland. But all sightings east of the island of Rügen (study area were only made in 2002. Thus, there is an enormous variation in the presence of habour porpoise in this area between the years. Currently surveys continue to determine how this area is used by harbour porpoises. Besides this, a clear west-east gradient in harbour porpoise density could be ascertained. The other two Baltic Sea study areas and are also used by porpoises, especially the area around the island of Fehmarn, but due to the small sizes of the areas additional investigation methods are applied, such as stationary acoustics (see chapter 12).

Harbour porpoises () were known to be common in the Baltic Sea. In the past several decades, the abundance and distribution has decreased, leading to national and international agreements on the protection of this species. Plans for offshore windmill constructions and proposals for Marine Protected Areas (MPAs) to implement NATURA 2000, led to an increased research effort on the harbour porpoise in the German Exclusive Economic Zones (EEZs) of the North and Baltic Sea. Within this scope, the harbour porpoise habitat use of the German Baltic Sea from Fehmarn to the was investigated with the help of self-contained submersible data logger (Porpoise detectors, T-PODs), which register harbour porpoise echolocation click trains.

Comparison of the T-POD data from different measuring stations located throughout the Baltic Sea revealed a decrease of porpoise registrations from the west of the island of Fehmarn to the east of the island of Rügen. Seasonal variation of habitat use, and therefore of relative porpoise density, was seen around the island of Fehmarn and the , with many days of porpoise registrations in the summer and fewer registration days in the winter months.

The results prove the regular use of the western part of the German EEZ of the Baltic Sea by harbour porpoises from Fehmarn to the including adjacent coastal waters. The low amount of porpoise registrations east of the Darss Sill () allows the assumption of a low harbour porpoise density in the eastern part of the German Baltic Sea. Furthermore, a clear seasonal variation in the amount of porpoise registration proves porpoise migration out of the western part of the German Baltic Sea in wintertime.

This paper gives a brief overview of the field methods used to study the distribution of seabirds at sea in the German parts of the North and Baltic Seas. It demonstrates how the data were analysed, how seabird concentrations may be delineated, and how suggestions for protected areas were derived from the data.

Seabird distribution was studied by transect counts from ships and aircraft. Species distribution maps produced from these data are based on densities. The distribution of widely dispersed species, e.g., lesser black-backed gull () and northern fulmar (), were analysed using grid maps. For species occurring in concentrations, a spatial interpolation procedure using ordinary kriging was adopted. Examples of distributions and maps are given for long-tailed duck (; Baltic Sea), common eider (; Baltic Sea) and red-throated and black-throated divers ( and ; North Sea). For all specially important species (i.e., species listed in Annex I of the EU Birds Directive that should be the subject of special conservation measures, e.g., red-throated diver and sandwich tern ), concentration areas were identified and subsequently combined so that a set of potential areas for conservation could be determined. From this map, potential Special Protection Areas (SPAs) were established.

Finally, this paper briefly discusses field methods and methods of analysis and gives further recommendations.

The joint research project MINOS examines whether large-scale offshore wind farms within the German parts of the North and Baltic Seas affect or endanger harbour porpoises, common seals, and seabirds. The research results are expected to provide the basis for estimating and assessing the impacts of future wind farms. MINOS focuses on two items: recording the preferential habitats and migratory routes of these animals in the EEZ, and investigating the sensitivity of porpoises and seals to sound, in order to assess possible damage, displacement and disturbance. When evaluating overall impacts to these animals, any expected impact of offshore wind farms must be considered in the context of already existing stressors.

The goal of the research is not to prevent or to hamper wind farming, but to provide a profound and reproducible knowledge basis for assessment in order to facilitate the development of sustainable power generation. This decision will not be taken by biologists or geologists, but by authorities or in court.

Since harbour porpoises have an ultrasonic location system (like bats), they are very sensitive to underwater noise. The noise produced during the construction and operation of offshore wind turbines, could cause behavioural changes or even physical harm to these animals. Such disturbances could displace the porpoises from their feeding and breeding habitats or otherwise reduce their fitness due to higher stress. Similar effects could also be expected to apply to common seals. Preliminary results indicate that harbour porpoises and common seals avoid sources that emit sounds similar to that of wind turbines.

With regard to seabirds, MINOS has focused on divers and sea ducks, which have important wintering grounds in the North and Baltic Seas within the German EEZ. The construction of offshore wind farms within these areas should be assessed with regard to possible detrimental consequences caused by the loss or interruption of diver and sea duck resting and feeding habitats.

MINOS has also developed and expanded upon research and evaluation methods for future use in monitoring programmes. Resting seabirds and harbour porpoises were counted using low altitude aerial transect surveys. Complex mathematical modelling was used to estimate the abundance of animals. Similarly, ship surveys were also carried out. Telemetry was used to record spatial activity patterns of seals. Hearing tests were carried out with free-ranging porpoises and seals and their conspecifics in captivity. Finally, porpoise detectors (POD) were employed to detect the presence of porpoises in the vicinity. These detectors can function for several weeks, but cannot determine the relative number of animals; nonetheless, they provide important additional results to the numbers gained through airborne and at-sea surveys.

The above-described research has been conducted in seven separate subprojects, integrated into the MINOS-project and its successor, MINOSplus (see chapters 10, 11, 12 and 13). All projects were funded by the German Federal Ministry for the Environment, Nature Conservation and Nuclear Safety.

The amendment to the German Federal Nature Conservation Act (BNatSchG) in April 2002 established a national legal framework for the implementation of the European Birds Directive and the Habitats Directive beyond Territorial Waters into the German Exclusive Economic Zone (EEZ). Responsibility for the selection, designation and management of these marine NATURA 2000 areas lies with the Federal Government. In selecting the protected areas in accordance with Article 38(2) of the German Federal Nature Conservation Act, the Federal Environment Ministry consults relevant Federal ministries from the adjacent coastal Länder as well as the general public. The proposed areas were listed and mapped on the Internet under www..de. The list was also published through newspaper advertisements and press releases in November 2003. These initiated the participation process of the public. Each citizen had the opportunity to submit a written comment or to contribute to the expert debate in public. For that purpose, three public hearing dates were held in the coastal Länder in December 2003. The federal ministries were involved in 2003 and once again involved from the beginning of 2004. The final proposals for NATURA 2000 sites (proposed Sites of Community Importance, pSCIs) were submitted to the European Commission in May 2004.

Parallel to the selection and nomination process of the marine NATURA 2000 sites, a presentation concept for increasing public awareness was developed and implemented. This was the research project “developing and implementing a presentation concept to increase public awareness”. Starting in late summer 2002, four different products for conveying information were designed:

These four products were developed almost at the same time, but they were published in two phases with slightly differing goals and target groups, depending on the status of the nomination procedure. Initially, the video, the website and the booklet were prepared. Their publication date was June 2003 at the joint ministerial meeting of the Helsinki and OSPAR Commissions with the Baltic and North Sea riparian states in Bremen. The interactive CD-Rom will be published in the second half of 2005.

All products confirm under the main title and name . The initial subheading, “Research for protection of the North and Baltic Seas”, was updated in summer 2004 to “Research and protection for the North Sea and Baltic Sea”, according to the nomination procedure of the protected areas.