Scientific research
Searching for nests and identifying territories occupied by the lesser spotted eagle
Observations are made between April-July under favorable meteorological conditions from locations with good visibility (observation points) and last from 2-3 hours. Observations are made with binoculars (at least 8×40) and/or a telescope (20×60). Once the observation point is reached, its GPS coordinates are logged.
The beginning and end of the observation are written down. Every recording of a bird of prey or black stork is logged via the mobile application Smartbird Pro, with the observer placing the recording as precisely as possible on the satellite imagery on the application’s map. The number, species, and behavior of the recorded birds is reported and, if possible, the age and sex of each individual. If a nest is found, it is described, its GPS coordinates are logged and a picture is taken of the tree where the nest is located.
If the nest is visited during the brooding period, the researcher strives as much as possible not to disturb the birds by limiting his or her stay at the nest to no more than 30 minutes. The location of every tree with a nest is recorded in the mobile app “Smartbird Pro”. The biological species of the bird that has occupied the nest is indicated by its generic and specific names.
Important! Information about threats in the region of a located nest or in the region of identified occupied territories is provided, including: the type of threat, the impact on the habitat and/or on the species of birds, and other information deemed significant by the expert in the field.
Places where birds of prey or black storks who are showing nesting behavior (mating games, protecting their nesting territory, carrying food, frequently visiting hidden areas) have been recorded, but whose actual nests are not found, are visited between November-March after the leaves have fallen to find and record their nests. Paths are made in order to closely examine the crowns of trees and record the nests. The paths are 30 m apart from one another in order to avoid the possibility of missing a nest.
MAPPING AND ANALYSIS OF THE FORAGING HABITAT AND DIET OF THE LESSER SPOTTED EAGLE
The aim of these activities is to investigate the impact of different land management practices on the reproduction, food base, resources availability, habitats use and habitats quality of the Lesser Spotted Eagle population. Eagle pairs that occupy optimal habitats breed successfully and raise offspring, whereas those that occupy habitats in poor condition produce fewer offspring or do not breed at all.
Knowledge of the regional foraging preferences of the species, as well as the availability of food resources, is a tool for planning specific conservation activities in particular areas. With this project, we aim to extend the knowledge gained within the Eagle’s Forests project (LIFE12 NAT/BG/001218) by investigating the foraging preferences of the Lesser Spotted Eagle in Central and North-eastern Bulgaria. The habitats of the species in these areas are quite different from those in the already studied south-eastern part of the country, being characterized by a significantly less pronounced mosaic pattern. This also suggests differences in the eagle’s food spectrum and perhaps the presence of different factors limiting prey availability and abundance.
The aim of these activities is to investigate the impact of different land management practices on the reproduction, food base, resources availability, habitats use and habitats quality of the Lesser Spotted Eagle population. Eagle pairs that occupy optimal habitats breed successfully and raise offspring, whereas those that occupy habitats in poor condition produce fewer offspring or do not breed at all.
Knowledge of the regional foraging preferences of the species, as well as the availability of food resources, is a tool for planning specific conservation activities in particular areas. With this project, we aim to extend the knowledge gained within the Eagle’s Forests project (LIFE12 NAT/BG/001218) by investigating the foraging preferences of the Lesser Spotted Eagle in Central and North-eastern Bulgaria. The habitats of the species in these areas are quite different from those in the already studied south-eastern part of the country, being characterized by a significantly less pronounced mosaic pattern. This also suggests differences in the eagle’s food spectrum and perhaps the presence of different factors limiting prey availability and abundance.
IDENTIFication of BEST PRACTICES FOR CREATING AND MAINTAINING THE ECOTONE BETWEEN FORESTS AND OPEN SPACES
A number of studies indicate that Lesser Spotted Eagles choose to nest near the forest edge, glades occupied by shrub-grass communities, and agricultural lands. This suggests proximity to available and accessible food resources. Consistent with these findings, the highest densities of the species in South-eastern Bulgaria were found in areas with high forest fragmentation and presence of extensive open spaces.
This preparatory component aims to identify, and subsequently implement, best practices for improving and maintaining open spaces and ecotone structure in a way that benefits the Lesser Spotted Eagle foraging habitat and resources. Best practices and models for improving and maintaining foraging habitat and the food base for the species may include:
restoration
of abandoned grassland and shrub-grassland communities;
conversion
of arable land to grassland or implementation of favourable crop rotation schemes, restoration of shrub vegetation, rotational grazing and its effective management;
construction
of foraging trenches and other methods to increase the abundance of prey used by the species;
Practices for creating, restoring, and maintaining forest landscape structures and areas where forests border open areas. These include:
creation and restoration
of forest shelter belts, which are important resting areas during migration as well as for nesting of the Lesser Spotted Eagle;
restoration and maintenance
of transitional tree-shrub vegetation ecotone as a key habitat for species’ prey.
The data obtained from the investigations and analyses carried out under the activity will be summarized in short information materials presenting the results. The results of the activity will be used for the management needs of the project areas.
Marking with satellite transmitters
As part of the project, there is a plan to place 10 satellite GPS/GSM transmitters on young Lesser Spotted Eagles. Their placement happens in the eagles’ nests when they are at the age just before starting to fly. The goal is to establish a model of the young birds’ dispersion, their migration route, their temporary stopover sites, as well as to collect important information about threats to wintering sites and to their entire migration route.
This will make clear which habitats they use and prefer, as well as their survival rate. The information collected will help in making demographic models of the species, as well as outline the basic guidelines for more effective preservation not only on a regional level, but on a worldwide scale as well. The plan is for the birds, on whom the satellite transmitters will be placed, to be from nests found in different geographical regions—southeast, central, and northeast Bulgaria—in order to avoid regional repetition.