Søgaard, B. & Asferg T. (red.) 2009: Arter 2007. NOVANA. Danmarks Miljøundersøgelser, Aarhus Universitet. 140 s. – Faglig rapport fra DMU nr. 713.
Denmark has obtained systematic monitoring of habitats and species included in the Habitats Directive and the Wild Birds Directive through the launch of the National program for Monitoring of Aquatic Environment and Nature (NOVANA).
A network of special protected areas has been designated according to the EU Directives. The network, ”Natura 2000”, contains species and habitats, which need protection within the European Union. A main purpose for these areas is to contribute to secure the biological diversity both on a national and EU scale. This will happen through maintenance or restoring of ’favourable conservation status’ for the habitats and species, which the areas have been designated to protect.
The monitoring programme for species within NOVANA has as primary target to monitor population size and distribution of the relevant species. This will in time provide the scientific background to assess conservation status for each species and strengthen the basis for deciding on any measures that might be able to improve conservation status for one or more species.
The monitoring programme for species has preliminarily been planned for the period 2004-2009. It includes selected plant and animal species included in the Habitats Directive and birds protected by the Wild Birds Directive (breeding birds and regularly occurring migratory birds). In addition the monitoring programme includes species, for which more than 20 % of the total population occur in Denmark (species of special national responsibility).
In chapter three the results of the monitoring in 2007 of species included in Annex II and Annex IV of the Habitats Directive are presented with an evaluation of the status of the species. The monitoring programme includes one amphibian (Bombina bombina), five insects (Ophiogomphus Cecilia, Leucorrhina pectoralis, Aeshna viridis, Dytiscus latissimus and Graphoderus bilineatus), three species of Vertigo snails (Vertigo moulinsiana, Vertigo angustior and Vertigo geyeri), five vascular plants (Botrychium simplex, Cypripedium calceolus, Liparis loeselii, Najas flexilis and Saxifraga hirculus) and one bryophyte (Buxbaumia viridis ). For most of the species the results of the monitoring constitutes a baseline for comparisons of the monitoring results in the future. Especially for the Vertigo snails the monitoring and mapping of distribution of these species are carried out for the first time in Denmark. Time series of data already exists for some of the monitored species, that makes assessment of changes in distribution or population size possible. For instance vascular plants species included on the Annex II of the Habitats Directive - except Najas flexilis - has been monitored yearly since the onset of the NOVANA-programme in 2004.
In chapter four the results of the monitoring in 2007 of breeding birds on Annex I on the Wild Birds Directive and Cormorant are presented together with the results of the monitoring programme of staging and wintering waterbirds.
The monitoring of breeding birds was accomplished by the environmental centres and included in 2007 10 species: Crane, Kentish Plover (Charadrius alexandrinus), Golden Plover (Pluvialis apricaria), the Baltic subspecies of Dunlin (Calidris alpina schinzii), Ruff (Philomachus pugnax), Wood Sandpiper (Tringa glareola), Gull-billed Tern (Gelochelidon nilotica), Black Tern (Chlidonias niger), Short-eared Owl (Asio flammeus) and Tawny Pipit (Anthus campestris ). Gull-billed Tern and Tawny Pipit were not registered as breeding birds in 2007, and can thus no longer be considered annual breeding birds in Denmark. Kentish Plover and Black Tern might have stabilised on a low level. Both seem dependant on targeted management of the few remaining breeding areas. The status of the Danish breeding birds is generally well known and a data set for comparisons of distribution and population size of the species already exist.
The monitoring of staging and wintering waterbirds in 2007 was carried out by the National Environmental Research Institute, University of Aarhus. The purpose of this monitoring scheme is to obtain the scientific background to evaluate the status for the migratory waterbird species, which are mentioned in the designation document for one or more Special Protection Areas designated according to the Wild Birds Directive. A number of surveys are international and carried out simultaneously all over Europe. In 2007 a countrywide mid-winter survey of waterbirds was planned. However, weather conditions were unfavourable for aerial surveys of waterbirds and the countrywide surveys had to be postponed to 2008. Thus, in 2007 only a reduced mid-winter survey was obtained. An international survey of Barnacle Geese (Branta leucopsis) in March was supplemented with a count of Pink-footed Geese (Anser brachyrhynchus). In May Dark-bellied Brent Goose (Branta b. bernicla) and Light-bellied Brent Goose (Branta b. hrota) were monitored. The count in August targeted the wader species: Avoset (Recurvirostra avosetta), Grey Plover (Pluvialis squatarola), Curlew (Numenius arquata), Redshank (Tringa totanus) and Greenshank (Tringa nebularia). Grey-lag Goose (Anser anser) was monitored in September, dabbling ducks together with Light-bellied Brent Goose and Pochard (Aythya ferina) in October simultaneously with a count of Oystercatcher (Haematopus ostralegus). Finally, a survey of Bewick’s Swan (Cygnus bewickii ) took place in the beginning of November.
The results of the monitoring of species in 2007 will in addition with the results of the NOVANA monitoring in the future contribute to the development of a scientific basis to identify changes in population size and distribution of species and thus to the conservation status of the species.
In chapter five the results of the monitoring of trends during a 20 year period for the migratory waterbirds in the Danish Wadden Sea are presented. The trends are dominated by species that are increasing or stable (22 species out of a total of 33 species). The other species are either decreasing (8 species) or show fluctuating numbers (3 species). The distribution and numbers in the Danish Wadden Sea is given for six selected species: barnacle goose, dark-bellied brent goose, teal, pintail, oystercatcher and bar-tailed godwit.
In chapter six emphasis is placed upon species and climate change, where a group of researchers ask the question ”Waterbirds and submerged macrophytes in fjords affected by global warming – do we and the birds have problems in Denmark?”. The section begins by establishing the importance of Denmark, in an international context as a vital “larder” for large numbers of migrating waterbirds that breed to the north of, and winter in, or to the south of, Danish waters. There follows a list of herbivorous waterbirds that wholly or partly survive by feeding on submerged macrophytes, together with other species that feed on plant seeds or invertebrates are associated with the bottom flora. Eleven of these species, which are entirely or partly dependent upon submerged vegetation, occur in internationally important numbers in several EU Special Protection Areas and feature in the site safeguard citation for these SPAs. Four of these selected for analysis, i.e. Mute Swan, Light-bellied Brent Goose, Wigeon and Coot are shown to be of stable or increasing numbers in Denmark. Studies have shown that existing problems associated with anoxia in Denmark will worsen under continuing warming in the future, which gives cause for continued concern. It is well demonstrated that incidents of eutrophication and/or anoxia has had adverse effects on the bottom vegetation of many Danish fiords and the disappearance of submerged macrophytes has been associated with marked declines in waterbirds, most notably shown by documented cases at Nissum and Ringkøbing Fiords and at Nibe Bredning and Gjøl Bredning. In addition to this eelgrass and other macrophytes are adapted to the temperature, salinity and light conditions they live in. The species also has a poor dispersal capacity and a fragmented distribution in Europe. This means that eelgrass adapted to future Danish climate scenarios might have to be spread more than 1000 km, a range probably beyond the species dispersal capacity, and has to do so through habitats distinctly different from the inner Danish waters, hence this seems unlikely to happen in reality. If the experiences from the case studies from Jutland fiords become more widespread in fiords and lagoons throughout Denmark, there are good reasons to fear for the conservation status of waterbirds in these areas and for their long term future well-being. Some of these species will shift to adjacent farmland areas to feed, creating the potential for increased agricultural conflict, a problem potentially further exacerbated by elevated survival rates in populations experiencing a climate dominated by milder winters.
Full report in Danish pdf (8 MB)
