On the 22.03.2012 a team from Romania made of 5 employees and volunteers of Milvus Group, working in the Saker Falcon conservation project LIFE09 NAT/HU/000384, travelled to Sarajevo, Bosnia and Herzegovina. There we were kindly welcomed by two local ornithologist colleagues, Mr. Dražen Kotrošan and Mr. Iljan Dervovič, members of Ornitološko društvo “Naše ptice” (Ornithological Society „Our Birds“, an NGO from Bosnia and Herzegovina, dedicated to the protection of birds) who helped us a lot during our visit.
The aim of our trip was to recover the satellite transmitter, which was mounted last year in Romania on a juvenile female Saker, named Maia (VIDEO), and to answer our question if whether the transmitter has simply fallen from the back of the bird, or the bird died. In the latter case, we hoped to be able to identify the causes of death as well.
In 2011 after she fledged from the one and only known Saker nest from Romania, Maia has spent a fair amount of time in the northern part of Serbia, in Vojvodina. There she was visited on 15.09.2011 by the employees and volunteers of Milvus Group, where she offered us valuable information about the dispersion of the juvenile Saker Falcons, their feeding, their behaviour in the first year of their life, etc. For more information about this issue, please click here.
In the middle of this hard winter on the European continent, on the first day of February Maia left Serbia, and oriented to west, towards Croatia. There she spent approximately 10 days, after which she flew south, in the direction of the Adriatic Sea and she stopped a few kilometres from the northern part of Sarajevo, the capital of Bosnia. Due to the diffuse and hard to interpret signals we can only affirm that on the 10th of February she was still in Croatia and on 13th of February the Saker was already in the northern part of Sarajevo. We couldn’t interpret the data between these two locations because of its weakness. After another week we received signal from the same place, which is not common at all for a Saker Falcon. Then we were confirmed that something happened indeed. In this way our Hungarian colleagues contacted the ornithologist colleagues from Bosnia. They went to the location, searched the place without any results, but we have to admit that their quest was hampered by the bad weather conditions in that period.
In the beginning of April the satellite transmitter of Maia sent signals again from the northern part of Sarajevo, from a forest on a hill, couple of hundred metres away from the signal we got in February. We decided that it is worth to search profoundly the area, so we travelled there and searched thorough the places where the signals came from.
After couple of hours we managed to find the transmitter, the ornithological ring and the remains of the bird consisting of pulled feathers and the bird’s thorax. The marks indicated that the feathers were pulled by a mammal, probably after the death of the Saker.
Unfortunately we couldn’t identify the cause of her death for sure, yet some assumption can be made and there are two reasonable causes. The area and the habitat where we found the remains of the Saker is formed by hills covered by extended forests. Maia, as well as other juvenile Sakers, probably was just passing by this area orienting to south, flying to South Europe during winter being a common behaviour for this species. In this area we assume that either she was caught by another raptor bird or she suffered of hunger and died there.
Besides that we regained a satellite transmitter, which in the future can be used on other birds, the experiences which Maia gave us from the beginning of the mounting of the transmitter until the end, not just offered us valuable information about juvenile Sakers, but strengthens the necessity of conservation of this species, because of high mortality of juveniles and the multiple risks they are exposed to!