Unique opportunities to monitor environmental changes
The Environmental Specimen Bank contains a collection of samples from approximately 500,000 individuals or specimens, representing about 400 different species. One of the collection’s greatest strengths is its exceptionally long time series, with the oldest dating back nearly 60 years. By repeatedly collecting the same species from the same locations, often on an annual basis, unique opportunities are created to track environmental changes over decades.
The material has primarily been collected for studies of environmental contaminants, but today it also serves as an invaluable resource for a wide range of research areas, such as population genetic studies, dietary analyses, and investigations of stable isotopes, fatty acids, hormones, and drug residues.
On average, two different types of material are preserved from each specimen, but for larger animals, this can amount to more than ten different tissue samples from the same individual. In total, the bank contains approximately one million stored samples. Smaller species are often preserved whole, while larger individuals are preserved in the form of specific tissues and organs. In addition to the physical samples, there is also biometric data linked to the material contained in the Environmental Specimen Bank, which adds further dimensions to the biological material.
To prevent degradation, most of the material is stored vacuum-sealed and frozen at either -25 °C or -80 °C. Certain types of material are preserved at room temperature in our dry collections.
Fish from Limnic and Marine Environments
The Environmental Specimen Bank’s fish collection comprises about 60 species from both limnic and marine environments. Samples are collected systematically from 32 lakes and 25 coastal sites along both the east and west coasts as part of the national environmental monitoring of limnic and marine environments, but the collection is also continuously supplemented with specimens from other projects and donations. Particular focus is placed on the following species, which form the basis of the monitoring:
- Herring (Clupea harengus): approximately 123,000 individuals
- Perch (Perca fluviatilis): approximately 71,000 individuals
- Eelpout (Zoarces viviparus): approximately 11,000 individuals
- Pike (Esox lucius): approximately 5,000 individuals
- Arctic char (Salvelinus alpinus): approximately 6,000 individuals
- Cod (Gadus morhua): approximately 6,000 individuals
The most extensive time series we have are those of perch and herring, with the oldest samples dating back to the 1960s. One of the collection’s longest series consists of pike from lakes Storvindeln and Bolmen; these series date back to 1966 and have been central to tracking the decline of environmental contaminants such as DDE and PCBs in aquatic ecosystems. In addition to the focus species, a large number of other fish species are represented in the collection in varying quantities.
The majority of the fish are preserved whole in a frozen state, but larger species are dissected and saved as separate tissue samples, typically consisting of muscle, liver, and gonads. While soft tissues are stored frozen, hard parts such as scales, otoliths, and cleithra are preserved as dry specimens at room temperature. For the individuals from which samples have been taken for analysis, biometric data such as length, weight, age, and reproductive status are also recorded.
Mussels and Other Mollusks
The Environmental Specimen Bank’s mollusk collection includes both marine and limnic species and serves as a basis for studies of long-term changes in aquatic environments. The majority of the material consists of blue mussels (Mytilus edulis), collected continuously from the 1980s onward at sites in both the Baltic Sea and along the west coast. The collection comprises approximately 43,000 individuals and includes frozen whole specimens, as well as annual and site-specific soft-tissue samples, and preserved shells in our dry collection.
For limnic environments, the collection of the common river snail (Viviparus viviparus) is more representative, with approximately 2,800 individuals. The collection was conducted in three Swedish lakes in Svealand and Götaland, with the oldest samples dating back to 2015. The material consists primarily of whole specimens stored in freezers. In addition, there are limited quantities of other mussel and snail species from both marine and limnic environments in the Environmental Specimen Bank.
Aquatic Mammals
The Environmental Specimen Bank has an extensive collection of mammals from aquatic environments, with 34 different species recorded, featuring specimens dating from the 1970s (when many of the Swedish species were on the verge of national extinction) to the present day. The samples are collected as part of the museum’s work on health monitoring and environmental contaminant analyses, often in close collaboration with the Swedish Veterinary Angency (SVA). The collection consists primarily of specimens from the following species:
- Gray seal (Halichoerus grypus): approximately 2,400 individuals
- Harbor seal (Phoca vitulina): approximately 1,300 individuals
- Ringed seal (Pusa hispida): approximately 800 individuals
- Porpoise (Phocoena phocoena): approximately 1,000 individuals
- Otter (Lutra lutra): approximately 2,400 individuals
During necropsies of aquatic mammals, biological data is collected, such as body length, blubber thickness, reproductive status, and age class. Multiple tissue samples are taken from all animals; primarily muscle, fatty tissue, and liver are preserved frozen, but in many cases other tissue types and materials are also preserved, such as lung, blood, fetuses, etc. In addition to the frozen material, parts of the skeleton and teeth are preserved in our dry collection, which are used, among other things, for age determination. For a significant majority of the individuals, extensive biometric data has been recorded.
The collection also includes material from several other whale species found dead in Swedish waters, including orcas (Orcinus orca), humpback whales (Megaptera novaeangliae), Atlantic white-sided dolphins (Lagenorhynchus acutus), and Sowerby’s beaked whales (Mesoplodon bidens). In addition, there is a limited number of samples collected from other countries.
Terrestrial mammals
There are 37 different species of terrestrial mammals recorded in the Environmental Specimen Bank’s collections. Several of the species stored in the Environmental Specimen Bank are classified as State-Owned Wildlife, and through close collaboration with the police and the Swedish Veterinary Agency (SVA), the Environmental Specimen Bank receives material annually from several terrestrial mammals, including the four large predators: brown bear (Ursus arctos), wolf (Canis lupus), lynx (Lynx lynx), and wolverine (Gulo gulo). Among our oldest tissue samples is a brown bear collected in Gällivare in 1964, and today the collection comprises approximately 700 individuals of the species. However, the largest number of samples from predators comes from lynx, with approximately 1,200 individuals collected from throughout Sweden between 1969 and the present.
In addition to predators, the collection also includes a significant number of tissue samples from herbivores. From the area around Grimsö, there is material from approximately 500 moose (Alces alces) collected since 1981. Furthermore, the collection includes samples from approximately 1,400 domestic reindeer (Rangifer tarandus tarandus), consisting of soft tissue as well as jawbones used for age determination, collected in connection with antler harvesting in the Swedish mountain regions between 1986 and 2016.
The Environmental Specimen Bank also includes a collection of small rodents and shrews that have been collected since 1979 through the “Environmental Monitoring of Small Rodents” program, which is managed by the Swedish University of Agricultural Sciences (SLU). These specimens have been collected at varying intervals from various parts of the country, from Skåne in the south to Vindeln in the north, and the animals are generally preserved whole and frozen.
For larger mammals, primarily samples of muscle, liver, and kidney are preserved in a frozen state. Additional species are represented in the collection in smaller quantities, including material collected in other countries.
Fåglar
The Environmental Specimen Bank’s bird collection comprises 194 different species and has its historical roots in research analyzing mercury (Hg) in bird feathers. The collection of birds of prey high up in the food chain from the 1960s onward is closely linked to the fact that these species were on the verge of national extinction due to environmental contaminants. The majority of the species included in the regular collection are listed as State-Owned Wildlife and are submitted to the museum when individuals are found dead in the wild, for example:
- White-tailed eagle (Haliaeetus albicilla)
- Golden eagle (Aquila chrysaetos)
- Eurasian eagle owl (Bubo bubo)
- Great grey owl (Strix nebulosa)
- Ural owl (Strix uralensis)
- Tawny owl* (Strix aluco)
- Northern hawk owl (Surnia ulula)
- Peregrine falcon (Falco peregrinus)
- Common kestrel (Falco tinnunculus)
- Merlin (Falco columbarius)
- Osprey (Pandion haliaetus)
- Red kite (Milvus milvus)
- Common buzzard* (Buteo buteo)
- Common kingfisher (Alcedo atthis)
*The tawny owl and the common buzzard are not listed as State-Owned Wildlife but are collected as part of other monitoring programs
Among the oldest time series are those for the white-tailed eagle, dating back to 1965, and the Eurasian eagle owl, dating back to 1972.
During necropsy, several samples are collected; primarily body feathers, muscle, liver, and kidneys, which are preserved frozen, while wing and hand feathers are preserved as dry specimens at room temperature. In conjunction with sampling, a variety of biometric data is also collected, such as the bird’s weight and measurements. Nutritional status is assessed, sex is determined by examining the gonads, and age is determined by the plumage or, in cases where the individual is banded, more precisely through previous banding records.
The collection also includes a long-term series of common starlings (Sturnus vulgaris) collected from about ten locations. The oldest time series come from areas around the lakes Krankesjön and Kvismaren and were collected from the late 1960s through 2016. The specimens collected are nestlings, which are preserved whole and frozen; collection ceased in 2016 due to a decline in the starling population. Overall, the birds represent a mix of migratory and resident species that reflect different environments and ecological roles. In addition to the Swedish material, there is a limited amount of material from the Arctic and Antarctica collected during the museum’s previous expeditions, as well as a number of other species represented by a limited amount of material.
Bird Eggs
The Environmental Specimen Bank holds an extensive collection of bird eggs from numerous species, with both the eggshells and the egg contents preserved. The eggshells are stored as dried specimens at room temperature, while the egg contents are preserved frozen for future analysis. Among the oldest and most significant time series are approximately 1,500 eggs from the common guillemot (Uria aalge), collected continuously at Stora Karlsö since 1968. The collection also includes time series for the white-tailed eagle (Haliaeetus albicilla)—approximately 1,700 eggs from the 1960s onward—as well as the peregrine falcon (Falco peregrinus), from 1972 onward.
In addition to ongoing environmental monitoring, material is collected through specific projects. Since 1973, osprey (Pandion haliaetus) eggs have been collected every five years as part of Project Osprey. Since 2011, eggs from the common tern (Sterna hirundo), approximately 140, and the Eurasian oystercatcher (Haematopus ostralegus), approximately 120, have also been included as part of the environmental monitoring of the marine environment.
Upon arrival at the museum, the eggs are weighed and measured, and after sample preparation, the thickness of the eggshells is measured. Eggshell thickness has historically been a crucial indicator for monitoring the effects of the insecticide DDT, which has affected the reproductive capacity of birds of prey by causing thinner eggshells.
Moss in Terrestrial Environmental Monitoring
The Environmental Specimen Bank stores moss collected since the 1970s, most of which comes from the national surveys conducted every five years since 1975. The primary purpose of collecting moss is to study airborne deposition of metals in the Swedish environment and how it changes over time.
The main material in the collection consists of red-stemmed feathermoss (Pleurozium schreberi) and glittering woodmoss (Hylocomium splendens). In addition to these, there are a limited number of samples from a handful of other moss species. The vast majority of the material is stored as dried specimens at room temperature, but the collection also includes a few frozen samples.
A Collection of Sediments and Sewage Sludge
The Environmental Specimen Bank’s collection also includes material from abiotic environments in the form of sediments and sewage sludge. Since 2006, sediments from several lakes have been collected, and the collection currently comprises approximately 500 samples. In addition to limnic sediments, there is an extensive time series of sewage sludge from several of Sweden’s wastewater treatment plants. This collection has been ongoing since 2004 and currently comprises approximately 1,500 samples. Both of these sample types are stored frozen to enable future analyses of, among other things, environmental contaminants.
Since 2026, the Environmental Specimen Bank has also held a collection of marine sediment samples from the Geological Survey of Sweden (SGU), collected as part of the national environmental monitoring of offshore sediments. The collection, which began in 2003 with sampling every five to six years, includes freeze-dried surface sediments and dated sediment cores. The material is primarily used for studies of metals and organic environmental contaminants, and the collection is continuously expanded with newly collected material from 16 different sites.
Breast Milk
Breast milk collected since the 1970s and onwards have been stored at the Environmental Specimen Bank. The milk is collected through child health centers and hospitals in Stockholm and Gothenburg as part of the Swedish Environmental Protection Agency’s environmental monitoring. A small number of samples have also been collected from Umeå, Östersund, and Lund. In total, approximately 1,500 mothers have donated breast milk to the bank.
The material is used, among other things, to investigate which environmental contaminants humans are exposed to and in what quantities.
Other Material
In addition to the species and sample types described in the respective sections, the Environmental Specimen Bank also includes smaller quantities of material from a number of other species and, in some cases, samples collected through international collaborations. The material ranges from terrestrial plants, lichens, and insects to aquatic invertebrates, amphibians, and reptiles. Researchers seeking specific species, geographic areas, or time periods are welcome to contact us for more detailed information about available material.