OBSERVER: The State of European Birds and Conservation Efforts: Leveraging Space-based Monitoring for Ecosystem Health
Birds as Indicators: Safeguarding Avian Species for Assessing Ecosystem Health in the EU
One of the first pieces of environmental legislation ever adopted by the European Union (EU) was the Birds Directive in 1979. Its primary objective was to protect all native European bird species and the habitats they depend on seeing as they are integral parts of almost every land ecosystem on the planet. They act as seed dispersers, pest controllers, scavengers, food sources for other animals and even apex predators. Indeed, birds are so tightly woven into the fabric of most ecosystems that they are often considered “indicator species”. By assessing the health of certain bird populations, you can get a good idea of how healthy the ecosystem is overall.
Challenges and Conservation Efforts: Assessing the State of European Birds amidst Urbanisation and Climate Change
Despite the passing of the Birds Directive and unceasing effort from conservation biologists, European birds have continued to face challenges over the last four and half decades. For the most part, this is owed to the ever-intensifying urban and agricultural sprawl associated with modern human civilisation. While the destruction and fragmentation of natural habitats is the primary driver of decline, pollution, climate change and over-hunting are also contributing factors. According to the European Environment Agency’s (EEA) latest State of nature report in 2022, just 47% of European bird species have populations that are considered to be in good condition. This number is 5% lower than the last State of Nature report in 2015.
Relative proportions of species from various avian taxonomic groups in the species assessments (left) and species conservation status (right). Figures taken from EEA State of Nature report, 2022.
This steady decline is not for lack of effort but the habitats these bird species rely on are often subject to multiple and conflicting demands. On top of this, technological limitations have historically hampered the ability of researchers to monitor habitats at scale, assess the impacts of climate change and plan effective conservation strategies at the national and continental level.
Revolutionising Conservation: Leveraging Space-based Monitoring for Sustainable Land, Resource and Ecosystem Management in Europe
Fortunately, space-based global and continental-scale land monitoring efforts have been deployed in recent decades. Initiatives like the European Union’s Copernicus program and its Land Monitoring Service (CLMS) provide comprehensive and high-quality information on land cover and land use across Europe, helping a wide swathe of users make informed decisions about the best ways to manage natural resources and ecosystems. Funded through the EU budget, CLMS boasts an extensive portfolio of data products designed for intensive monitoring of a variety of land cover classes such as forests, grasslands, waterways and urban environments. The CORINE Land Cover (CLC) and High-Resolution Snow and Ice (HRSI) products in particular have been used by bird conservation researchers to address some of the problems conservation biologists have historically faced. And like all Copernicus datasets, CLMS products, including CLC, are free of charge and can be used by anyone.
Corine Land Cover products (CLC) facilitate studies of habitat use
Dr. Andrea Santangeli has dedicated his life to avian research, working across Europe from Sardinia to Scandinavia. Several of his studies have leveraged the extensive time series and coverage of the 44 distinct land cover and land use classes provided by CLC on a continental scale. In a notable study from 2011, Andrea used CLC to investigate the habitat preferences of the threatened little bustard (Tetrax tetrax) in Sardinia. He discovered that these birds had a preference for pastures and recently fallowed fields, and their densities increased the further away from roads they were, indicating a preference for less fragmented habitats.
CORINE land cover (CLC) map of the northern coast of Sardinia, Italy (top). Distinct land cover classes are indicated by different colours (see legend). Composite image of a Little Bustard male performing a courtship display (bottom).
More recently, Andrea investigated habitat use patterns in protected versus unprotected areas in Finland, also using CLC. He found that most bird species show different patterns of habitat use in unprotected versus protected areas. For example, a species might need to roost on rocky outcroppings in unprotected areas which have recently been clearcut instead of high in the branches of trees in protected areas. His current project is focused on investigating precisely how these behavioural shifts affect species survival.
CLC reveals olive grove expansion threatens bustards
In Andalusia in southern Spain, we find another instance of CLC being utilised in the context of Bustard conservation. Here, Dr. José Guerrero-Casado wondered what the repercussions of expanding olive groves were on the habitats of the great bustard (Otis tarda) and the little bustard (T. tetrax). In a 2022 study, he leveraged CLC land cover and land use maps and found that a considerable fraction of new olive groves built between 2000 and 2018 supplanted arable land. Arable land is the preferred habitat of these two bird species, and so its destruction inevitably leads to a contraction in the availability of suitable Bustard habitat. The new olive groves have high tree densities which make them unsuitable for steppe birds. In addition, these new olive groves may reduce visibility in adjacent areas, which could negatively impact these species' mating behaviours as both species require large areas of open land with good sight lines so females can witness male courtship displays.
The study also revealed that so-called Important Bird Areas (IBAs) were not very effective in preventing detrimental land-use changes. IBAs are sites identified using an internationally agreed set of criteria as being globally important for the conservation of bird populations and are meant to serve as safe harbours in an otherwise increasingly hostile landscape. And so, while IBAs are a useful tool for bird conservation, almost a quarter (21.2%) of new olive groves planted between 2000 and 2018 were planted in IBAs, suggesting that more intensive conservation efforts are required to prevent habitat loss due to agricultural intensification.
High-Resolution Snow and Ice (HRSI) products reveal snowfinch nesting preferences
If we travel from Italy and Finland high up into the Swiss Alps, we will find Carole Niffenegger hard at work amidst the snowpack. A PhD student at the Swiss Ornithological Institute, Carole has been studying the nesting habits of the white-winged snowfinch (Montifringilla nivalis), a bird species that thrives in high-altitude, snowy environments. Not much was previously known about their nesting behaviour, but due to their tendency to forage for food near melting snow, Carole suspected that snow coverage was crucial to their decision making. To test her hypothesis that snowfinches preferentially nest in snowy areas, she turned to the Copernicus Land Monitoring Service's High-Resolution Snow and Ice (HRSI) products, specifically the Fractional Snow Cover dataset, which provides detailed and near real-time information on snow cover patterns across Europe.
After using the dataset to track the snow cover in different regions of the Alps over several springs and comparing these data to the densities of snowfinch nests, Carole concluded that snowfinches do indeed prefer to nest in areas with higher snow cover. This choice ensures easy access to their primary springtime food source, crane fly larvae, which are found near melting snowpacks.
This research provides important insights for conservation efforts in the face of climate change, as changes in snow cover could significantly impact the already declining snowfinch population. Other Alpine species are also at risk, and Niffenegger's method of studying nesting habits could be similarly applied. The Copernicus Land Monitoring Service's publicly available data on snow and ice conditions could prove invaluable in developing future conservation strategies for at-risk species and their changing environments.
Fractional Snow Cover visualisation of Carole Niffenegger's general study area, southern Switzerland/northern Italy from June 2019. Areas in white are covered in snow, black areas are snow free, and grey represents cloud cover (top). White-winged snowfinch (Montifringilla nivalis) perched on rock, Swiss Alps (bottom).
Conservation decisions are bolstered by accurate, local data
These sorts of studies underscore the invaluable role of tools like the CORINE Land Cover and High-Resolution Snow and Ice products in understanding and addressing the challenges faced by bird species in Europe. As we continue to grapple with the impacts of urban and agricultural expansion, pollution and climate change, these CLMS products can provide us with the means to monitor habitats at scale, assess the impacts of these threats and plan effective conservation strategies. The work of researchers like Andrea Santangeli, Carole Niffenegger and Jose Guerrero-Casado is a testament to the unceasing efforts of conservation biologists to protect birds and the ecosystems they inhabit.
Other products in the Copernicus Land Monitoring Service portfolio have the potential to assist in bird conservation efforts as well. The High-Resolution Water & Wetness product, for example, provides detailed information about the presence and condition of water and wet surfaces across Europe. It is easy to imagine this data being leveraged to monitor essential waterfowl habitat such as lakes, streams and wetlands, and in turn helping to shape conservation plans. Similarly, the Coastal Zones product offers land cover and land maps of Europe’s coastal areas, which would allow conservationists to monitor urban expansion or restoration efforts in these sensitive bird habitats.
The goal of conservation is not just to preserve what we have, but also to create a world where human civilisation and environment are mutually beneficial. Leveraging state of the art datasets and tools like the ones provided by the Copernicus Land Monitoring Service can help bring us closer to achieving the original vision of the 1979 Birds Directive: 'to protect all native European bird species and the habitats they depend on'.