Birds´ collisions with power lines often happen because the birds are unable to detect the lines in their flying direction in time. Bird casualties due to collision with aboveground power lines can happen on distribution or transmission electricity grids. Frequently they can be observed especially in open areas where the power line crosses feeding, foraging, and nesting habitats used by birds. At greatest risk are the large, heavy bird species with low maneuverability, i.e. those with high wing loading and low aspect, such as bustards, pelicans, waterfowl, cranes, storks, and grouse.

The risk of collisions is higher at night, during dusk and dawn, and under weather conditions that cause poor visibility (fog, rain, strong wind,..). Such clashes at high speed have fatal consequences for birds.

A coordinated field survey of the potentially dangerous above-grounded power lines at the beginning of the project is essential in order to determine the most dangerous sections on which the flight diverters will be installed. 

Achieved results:

Within the first months of the project, more than 80 field assistants in all project countries were trained on how to conduct recognition and baseline field surveys. A recognition survey was held from January to April 2021 with the main aim of recognizing the most dangerous sections of power lines within the monitored project area. More than 1380 km of different voltages and construction power lines were searched during the recognition survey in all project countries. Based on the results, the surveyed power lines were divided into 3 categories: potentially dangerous, to be verified, and not dangerous. An Internation GIS online database has been designed in January 2022, containing all data from field surveys (read more HERE). The monitoring scheme was updated with the results to ensure the proper implementation of the baseline survey, under which the first two categories of power lines were being monitored regularly until April 2022. Read more about the baseline survey: HERE or HERE. As a result, 34 mitigation plans - a conflict map of the riskiest power lines in priority areas were prepared, specifying the selected power lines for the installation of the bird flight diverters. Around 245 km of top-priority lines will be treated with mitigation measures to increase their visibility by electric companies until the end of the project. So far, the flight diverters have been installed in these countries:

In Slovakia, our project partner SEPS already marked 30 km of transmission power lines 400 kV. The latest types of RIBE flight diverters (black and white lamellas) with glow-in-the-dark illumination have been installed on the shield wires. A special crane with a basket was used for the installation; all works were carried out on switched-off lines (read more HERE).

In Hungary, 7.7 km of 220 kV and 12 km of 400 kV transmission lines were highlighted so far with the flight diverters thanks to the strong effort of our project partner MAVIR. Four different types of diverters were used during the installations that were carried out with the help of the basket crane and drone (read more HERE).

In Croatia, 15 km of distribution power lines have been marked with the flight diverters by HEP in the period between December 2022 and March 2023 (read more HERE). The works on 10 kV and 110 kV lines will follow in 2024.

In Bulgaria, 5.8 km of distribution power lines have been marked by the EDG West.

In Austria, the Austrian Federal Railway company OEBB planned to insulate the railway electric poles under the project. However, it was found out that 12 males of Great Bustard (Otis tarda) were detected killed after the collision with a catenary system of the railway line. OEBB marked the lines with diverters immediately from its own sources concerning the extreme severity of the case.

The birds are in danger of electrocution mostly while they land on the utility poles and simultaneously come into the contact with a wire or when they touch the two conductors (wires) at once. The highest risk is associated primarily with medium voltage power lines representing very attractive perches to many birds in open rural areas without tree growth. The group most threatened with electrocution is defined as the diurnal bird species, specifically eagles, hawks, vultures, kites, falcons, owls, storks and corvids. The highest mortality rate due to electrocution is registered mainly for medium-sized and large birds as they are more likely to make simultaneous contacts with unprotected elements of the pole construction.

About 10909 potentially dangerous utility poles of medium-voltage power lines are located inside the LIFE Danube Free Sky project area. To identify the most hazardous out of these, a field survey will be held at the beginning of the project. The construction of at least 3256 poles will be insulated until the end of the project. Satellite transmitters will be used on juveniles to identify dangerous poles located in their home range and priority habitats.

Achieved results:

The identification of the riskiest utility poles was conducted during the recognition survey, under which 12 535 poles in the project area were inspected. Electrocution was proven a very important mortality factor for birds of prey. Metal branch pylons and corner pylons with exposed jumper wires passing over the supporting insulators above the cross arms seem to be the most dangerous configuration. Data are evaluated continuously, and special attention and the best technical solution will be given to all dangerous poles. After collecting all needed data and evaluating the results, mitigation measures have been planned and are being implemented:

In 2022, 20 km of 22 kV poles were insulated in Slovakia with the cooperation of the Coordinating Beneficiary Raptor Protection of Slovakia with an Energy Distributor for Western Slovakia (Západoslovenská distribučná, a.s.). In 2023 works continued and so far 522 dangerous poles have been insulated.

In Bulgaria, 490 risk poles have been insulated so far by the project partner EDG West. Altogether 1221 poles were identified to be secured until the end of the project.

In Austria, BirdLife Austria has been conducting the dog-assisted recognition survey on railway lines within the project areas (read more HERE), which has been increased by 2 SPA and the number of poles to be insulated has been increased from 640 to 868 poles in all 3 SPAs. 450 poles were already insulated by the project partner Austrian Federal Railway OEBB.

Insulation works in Croatia, Romania, and Serbia are planned to be finished in 2024.

Using satellite telemetry for identification of the dangerous poles and other threats that young birds need to face allows us to gain valuable and important data. Satellite transmitters were installed on 6 Saker Falcons in Slovakia in June 2021 (read more HERE), and in 2022 another 6 Imperial Eagles were tagged (read more HERE). In 2023, 6 more Saker Falcons have been tagged in Slovakia (read more and watch short video HERE), and 2 in Serbia (read more HERE).

Photo traps, video cameras, and nocturnal vision systems will be used to increase the detection efficiency and identify the scavenging rate. By this, the detection efficiency will be improved as well as the magnitude of bird mortality. Technical project guidelines (international monitoring scheme) to implement project actions will be prepared and adopted by all project partners during the project. Slovakia, Serbia, Romania, and Croatia will test around 400 cadavers found altogether for the presence of lead, a metal detector will be used to detect bullets. By this, we will be able to detect the influence of selected illegal activities on the behaviour of birds and mortality rates on power lines.

Achieved results:

An international monitoring scheme has been designed and distributed to all project partners and field assistants prior to the recognition survey. The scheme defines especially the main rules and recommendations for field survey and data transcription. The recognition survey defined the initial situation from which the project starts concerning the following data that will be collected: especially technical parameters of the power lines and data of bird carcasses.

The buffer for the surveys (recognition and baseline) was defined as a distance of 20 m from the edge phase-conductor in the case of medium voltage lines (10 kV, 22 kV, and 35 kV) and 50 m from the edge phases in the case of high and extra-high voltage lines (110 kV, 220 kV, and 400 kV). Walking in a zigzag pattern was carried out only in high and dense vegetation or crops. The slow, regular pace used during the survey optimized the results and decreased the searcher bias. The location of each bird carcasses or remains found was recorded by GPS device and described with seven parameters [identification by species or in the most precise taxonomic category possible, sex and age (if possible), cause of death (electrocution, collision, other or unknown cause of death), description of visible injury, stage of decomposition and effect of scavengers].

For each electricity pole and pylon, special technical data were collected together with other abiotic and biotic factors about the surrounding landscape structure and habitat important for birds. The information recorded for every single pole included: GPS coordinates, type (position in the line), number of circuits per line, the material of pole, number of vertical separation of wires, number of cross-arms, type of cross-arm, number of insulators per conductor, the position of insulators, presence, and type of insulators and their current quality state, presence and position on jumper wire.

All poles/ pylons were photographed for verification of the data collected in the field. All detected bird carcasses were removed from the area during the recognition survey to prevent double counts in the baseline survey.

Video cameras, binoculars, and nocturnal vision are being used within the observations of bird reactions on non-marked power lines. Observation of reactions is a part of the baseline survey, including also mortality survey under selected sections.

In areas within the project territory with low or no risk of collisions/electrocution, actions to create safe breeding opportunities and foraging habitats are being carried out in Serbia, Romania, Bulgaria, and Slovakia. Such measures will be focused on the most endangered among the target species, to attract the birds into safe zones and thus decrease the overall mortality of individuals/increase the population. By this, the overall goal of the project will be supported. 

The restoration of approximately 10 ha of land in Slovakia from arable land to pastures will increase the overall value of the land and its suitability, preferably for the Imperial Eagle, the Saker Falcon, and the Red-footed Falcon, whilst many other bird species will also benefit from the land restoration.

Achieved results:

In total, 370 new nest boxes have been installed. In Slovakia, 20 alternative nesting opportunities – nest boxes were installed for the Saker Falcon on 110 kV pylons (read more and watch a short video HERE), 50 wooden nest boxes for the Red-footed Falcon in Bulgaria (read more HERE), and 300 nest boxes were installed for European Roller in Slovakia (50 pcs), Bulgaria (50 pcs), Serbia (100 pcs), and Romania (100 pcs). Read HERE about the monitoring of the nest boxes and successful breeding season in Bulgaria and HERE about the survey conducted on the food spectrum of the European Roller.   

Site management of the 10 ha in Slovakia is in place: a special scheme for specific restoration and management of the land was prepared by the landscape manager. Regular control of the area continues, and the alfalfa seeds are on site, including visual control and expert monitoring of small mammals’ activity for further evaluation of management activities, as well as monitoring of the presence of bird target species.

Land leveling by a tractor with mowing of weeds and preparation of the field for seeding was done in the spring of 2021, with seeding of grass/red clover mixture seeds in March 2021, and the first mulching of new growth in July 2021. The project site with dense vegetation growth represents important refugium for small mammal populations as the surrounding fields were harvested and plowed. Expert monitoring of the small mammal population was done on-site, e.g. presence of the steppe mouse with typical mounds was confirmed on site.

In 2022, one mowing round was done and the biomass collected after the mowing was distributed to the local farmers for the livestock. In October 2022, 15 artificial wooden hunting stands in the "T" shape were mounted with the help of volunteers. Stands will substitute the role of electric poles and will be useful for raptors when hunting prey (read more HERE). 

Supporting agrotechnical interventions (aeration of land, followed by rolling) continued to support the quality of the vegetation. Thanks to the previous agrotechnical interventions implemented since 2021, despite the poorer rainfall, the vegetation was of good quality. In 2023, the first mowing was carried out at the beginning of June, and the second in the middle of July. Hay was of higher quality in 2023, and used as feed for local livestock.

The project site with dense vegetation growth represents an important refuge for small mammals as the surrounding fields were harvested and plowed very intensively.

Under Action D.1 the presence of target species was recorded as well as availability of prey sources by monitoring of small mammals and invertebrates. 

One of the aims of our project is to inform the target groups as well as the general public about project actions and activities. Public awareness activities aimed at publicizing the project as well as the importance of the Natura 2000 network are being held regularly both for the general public and stakeholders. Networking and the transfer of the methods/techniques/solutions applied in the project to other regions, countries, organizations, and experts will be ensured.

Achieved results: 

In November 2020, the coordinated project kick-off press release was released in all project countries. By 2023, 30 press releases were published, and 9 press conferences or events for media have been held. In all project countries, 531 different media clippings have been tracked so far. 22 notice boards describing the project and its main actions have been installed within the project areas, you can find the map of the locations: HERE. In 2022, the LIFE Programme celebrated its 30th birthday which was marked by various project events (e.g. HERE). Several project videos have been published so far, you can find them on our YouTube channel: HERE. The dissemination towards stakeholders and project presentation at several networking events was done (e.g. HERE), and we look forward to further networking opportunities.

3 new nest boxes for the Saker Falcon have been installed on 35 kV power lines pylons in Croatia with the cooperation of the Kopački rit Nature Park and energy distribution company HEP. One of the nest boxes was occupied by a pair of Common Kestrels on the first day after the installation. The pair managed to raise 4 chicks. The nest boxes are recorded with the cameras, read more HERE.