Projects / Programmes source: ARRS

Characteristics, problematic and management of populations of (Hooded) Crows in urban environment

Research activity

Code Science Field Subfield
4.01.01  Biotechnical sciences  Forestry, wood and paper technology  Forest - forestry 

Code Science Field
B280  Biomedical sciences  Animal ecology 

Code Science Field
4.01  Agricultural and Veterinary Sciences  Agriculture, Forestry and Fisheries 
Hooded crow, urban settlements, population monitoring, crows behaviour, telemetry, nest predation, conflicts with humans, education, public opinion
Evaluation (rules)
source: COBISS
Researchers (25)
no. Code Name and surname Research area Role Period No. of publications
1.  12031  PhD Samar Al Sayegh Petkovšek  Control and care of the environment  Researcher  2015 - 2016  330 
2.  32249  Branko Bakan  Biology  Researcher  2014 - 2016  100 
3.  24375  PhD Elena Bužan  Biology  Researcher  2014 - 2016  323 
4.  08032  PhD Miran Čas  Forestry, wood and paper technology  Researcher  2014 - 2015  243 
5.  29092  PhD Maarten De Groot  Forestry, wood and paper technology  Researcher  2014 - 2016  606 
6.  29426  PhD Dejan Firm  Biotechnical sciences  Researcher  2015 - 2016  57 
7.  35362  PhD Katarina Flajšman  Forestry, wood and paper technology  Junior researcher  2014 - 2016  163 
8.  23167  Boris Jakop    Technician  2014  14 
9.  13134  PhD Franc Janžekovič  Biology  Researcher  2014 - 2015  510 
10.  29582  PhD Ida Jelenko Turinek  Control and care of the environment  Researcher  2014 - 2016  163 
11.  22515  PhD Klemen Jerina  Forestry, wood and paper technology  Researcher  2014 - 2016  438 
12.  30210  PhD Tina Klenovšek  Biology  Researcher  2014 - 2015  93 
13.  17424  Franc Kljun    Technician  2014 - 2016  49 
14.  06960  PhD Ivan Kos  Biology  Researcher  2014 - 2016  545 
15.  23161  Klemen Kotnik  Geography  Researcher  2014  102 
16.  29816  PhD Miha Krofel  Forestry, wood and paper technology  Researcher  2015 - 2016  691 
17.  18112  PhD Boštjan Pokorny  Forestry, wood and paper technology  Principal Researcher  2014 - 2016  849 
18.  23000  PhD Helena Poličnik  Interdisciplinary research  Researcher  2014  215 
19.  18628  PhD Hubert Potočnik  Biology  Researcher  2014 - 2016  249 
20.  12467  PETER SKOBERNE  Control and care of the environment  Researcher  2014 - 2016  517 
21.  14455  PhD Andrej Sovinc  Biology  Researcher  2014 - 2015  258 
22.  31551  Matija Stergar    Researcher  2014  114 
23.  13962  PhD Andrej Šorgo  Educational studies  Researcher  2014 - 2016  727 
24.  18465  PhD Natalija Špeh  Geography  Researcher  2014 - 2016  190 
25.  23168  Marjeta Zaluberšek    Technician  2014  97 
Organisations (6)
no. Code Research organisation City Registration number No. of publications
1.  0404  Slovenian Forestry Institute  Ljubljana  5051673000  11,847 
2.  0481  University of Ljubljana, Biotechnical Faculty  Ljubljana  1626914  64,100 
3.  1007  Eurofins ERICo Slovenija Inštitut za ekološke raziskave d.o.o. (Slovene)  Velenje  5583055000  2,442 
4.  1510  Science and Research Centre Koper  Koper  7187416000  11,570 
5.  2547  University of Maribor, Faculty of natural sciences and mathematics  Maribor  5089638051  16,789 
6.  2872  Faculty of Environmental Protection   Velenje  2257092  3,182 
In recent decades, numbers of different corvid species have been increasing worldwide; in Europe, mainly Hooded Crow (Corvus cornix) and also Carrion Crow (Corvus corone) have been in expansion mostly in (sub)urban areas. Despite the lack of information about actual numbers of crow populations in Slovenia, it is clear that abundances of crows in Slovenia are increasing in the majority of larger cities. Increasing abundance of crows in (sub)urban areas in the last decades resulted in various problems or conflicts with humans. Conflicts, such as damage on property (particularly on infrastructure, furniture and cars), disturbance of residents due to crows noise, pollution of public areas with faeces and even attacks on humans, were also registered in Slovenia in the last decade. As an important disturbing factor of crow presence in urban environment, residents often mention predation of crows on nests of passerine birds and attacks on adults of smaller bird species. Their opinion is that crows may have severe impacts on population decline of these species. The main problems, connected with (hooded) crow presence in (urban) environments are as follows: (i) lack of the knowledge on the presence, abundance and population trends of hooded crow both in cities and in Slovenia in general; (ii) insufficient knowledge on the (hooded) crow’s ecology, their ecosystem roles and interspecific interactions in urban environment; (iii) increase in numbers of conflicts with humans and lacking knowledge on the factors that cause such events; (iv) lack of knowledge on efficiency of various methods and measures for reducing crow’s abundance, and particularly for reducing conflicts with humans: (v) uncontrolled actions, which may have – by generalizing the problem to the all crow species – negative impacts also on protected species, e.g. carrion crow (Corvus frugilegus); (vi) stigmatization of hooded crow as a pest species, which in (urban) environment exclusively negatively interacts with residents and has strong negative impact on other bird species. Systematic determination of problems, connected with hooded crows in urban areas of Slovenia and their solutions have to be made on multiple levels: (i) systematic studies on hooded crow’s ecology in urban environment, e.g. nesting habits, social organization, nest predation of other bird species, etc.; (ii) establishment of an on-line platform/system for recognition and registration of various conflict situations between residents and crows; (iii) analysing (also by the review of literature) and testing efficiency of various measures for reduction of crow’s numbers and conflicts with humans, and also preparing platforms for implementations of the most suitable measures into the practice; (iv) improvement of people’s attitudes and tolerance towards crows in urban environment. With this project proposal, we aim to contribute to a better knowledge and understanding of ecology and conflicts of (particularly hooded) crows in urban environment. We also aim to contribute to a better and more efficient management of populations of hooded crow, which would be acceptable for all stakeholders. The main objectives are as follows: (i) to estimate the abundance of hooded crow in Slovenia, by focusing on urban environments of all larger cities, and at the same time also to estimate the abundance of other corvid species – carrion crow, rook and jackdaw, respectively; (ii) to study the biology and social behaviour (territoriality, social organization, spatial patterns etc.) of »urban« hooded crows, compared to »non-urban« crows; (iii) to determine the hooded crow impacts (predation) on populations of other bird species; (iv) to identify problems, caused by hooded crow and other corvids in cities, and to establish an on-line platform for registration of such conflict events; (v) to test different measures for solving problems that occur at crow-human interactions, and to prepare suggestions, protocols and expertise f
Significance for science
Despite its abundance, large spatial distribution and several problems caused to humans the Hooded crow (as well as all other corvids) used to be almost unstudied species till recently. However, with the realisation of the project we obtained important new findings (also in a wider pan-European context) on the biology/ecology of the species as well as on possible management measures for reducing conflicts with people, as follows: (i) we obtained data on nesting preferences of Hooded crow in selected Slovene towns which will enable better planning of vegetation (trees) structure and form at the most problematic locations, i.e. at hot spots; (ii) as one of the first in the world, we studied spatial behaviour of Hooded crows in urbane environment by using telemetry; (iii) we obtained important new findings on the predation pressure of crows on nests of other birds’ species; (iv) preliminarily, we determined severity and importance of some conflict situations such as the influence of crows’ excrements on car body, input of nutrients (nitrogen, phosphorus) by crows’ excrements, and the influence of a massive use of trees by crows (for nesting and staying overnight) on trees’ vitality; (v) we obtained new, yet unknown information on attitudes of people towards crows, understanding of their value, and acceptability of several possible measures for reducing conflicts between people and crows. Considering development of science and profession it is of crucial importance that the project realization was based on integral and interdisciplinary approach, i.e. by collaborating and connecting knowledge and experiences of several Slovene wildlife researchers. These enabled upgrading of different knowledge (i.e. from biotechnical, natural-mathematical, and social sciences) which importantly refined partial data and findings. Importantly, for the first time all Slovene research institutions/groups working on game ecology (i.e. seven research groups coming from all three public universities, a private college, a public institute, and a research company, respectively) collaborated in the project team. Apart from strengthening interdisciplinarity of research in Slovenia, this had also important value for development of a very important (but yet almost overlooked) research field of wildlife ecology. For development of science, already achieved incorporation of the research group mambers and project results into the international research arena is of crucial importance (although this project had been planned as a very applicative one, we nevertheless managed to publish one original scientific paper in the international journal with IF, and another one is in front of us; moreover, results were presented also at two scientific conferences), and enables access to the foreign knowledge as well as its transfer toward the end-users. Consequently, we prepared solid basis for more intensive international activity and mobility of Slovene wildlife researchers, i.e. among others by agreements on the collaboration on crows’ research with colleagues from Hungary and Great Britain. By the realization of the project, we also improved the access to the research infrastructure (i.e. VHF/GPS collars, cages for catching crows) which will enable us realization of additional studies on crows and/or other size-comparable bird species in the future. In new projects, international collaboration will be emphasised, and we have been already agreed with colleagues from other countries (i.e. Hungary) about the preparation of some joint papers based primarily on data that were collected within the project.
Significance for the country
Project realization provided many answers which will enable responsible persons (particularly at the Ministry of Agriculture, Forestry and Food) to realize needed activities for education of inhabitants, both in terms of better knowledge about crows, reducing their negative stigmatization as well as implementing concrete measures for reducing possibilities for conflicts. For example, in collaboration with Slovenian Forestry Institute the Ministry has already prepared draft of the informative bulletin which will be at the disposal in all larger Slovene towns. For further activities, it is very important that several mitigation measures for reducing conflicts with crows were evaluated in the last part of the project considering their technical feasibility, public acceptability and legality, which will in turn enable accepting the most suitable measures in every specific situation. During the project duration, an intensive transfer of the scientific findings towards end-users was emphasised (i.e. presentations at the professional events, several presentations for representatives of the Ministry), and different activities for informing general public were also realized (particularly by preparing the official web-site of the project, and by providing intensive link between scientific and pedagogical processes). Moreover, the project contributed towards better education and qualification of our own experts who will be able to take active and leading role in Slovenian as well as in the international scientific communities. For example, a young researcher who have been educating in the field of game ecology was a member of the project team. Three master theses and four diploma theses were made at different study programmes at all collaborating high educational institutions (University of Ljubljana – Biotechnical Faculty; University of Maribor – Faculty of Natural Sciences and Mathematics; University of Primorska – Faculty of Mathematics, Natural Sciences and Information Technologies; Environmental Protection College), which enabled students to broad their knowledge and competences. This indicates an important social added value of the project. Interdisciplinary and heterogeneous research team will continue to collaborate also in the future, and it will foster connection among education, research and business, and consequently also contribute to better mobility of the knowledge, ideas and people in a society. New scientific findings obtained within the project, better access to foreign knowledge and particularly proactive shaping of public opinion and attitudes (i.e. increase of the tolerance towards crows, higher acceptability of different mitigation measures) will enable easier and more systematic approach towards solving of problems connected with the presence and increasing numbers of crows in the urban environment.
Most important scientific results Annual report 2015, final report
Most important socioeconomically and culturally relevant results Annual report 2015, final report
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