Report on the monitoring results of the released bears in 2009
In the summer of 2009, 7 brown bear cubs have been released from the BOS, 5 of them being equipped with GPS/ GSM collars. The used equipment was Vectronic- Aerospace brand, saving the coordinates of the animals every 4 hours.
The release of two bears (Vranceanca and Covas) was performed with a “hard release” method, this meaning that the cubs have been put under anesthesia and transported far away to the release site, respectively: Vranceanca in the Vrancea Mountains, in the South Eastern Carpathians (the provenience area), and Covas in Covasna County (also provenience area). The other three (Bamse, Zoologist, and CV2) has been released with a “soft method”- one of the enclosures being opened, the animals having the possibility to leave and return back by their free will.
In 2 weeks after the release one of the bears (CV2) took off the collar, fortunately without damaging it.
The post release monitoring of the other bears resulted extremely interesting data, changing radically the conception on brown bear’s movement dynamic and habitat use in the Carpathian Mountains. Below can be founded few analyze results and details on the movement and habitat use of 3 cubs (Bamse, Covas and Vranceanca), results which strongly demonstrate the success of the rehab work implemented in the Orphan Bear Rehab Centre- Romania.
These pictures show the Carpathian curve, and the GIS points of several monitored bears (left zoomed out, right- zoomed in). On the left table of each picture can be seen the colors of the three mentioned bears: Vranceanca has the pink color, Covas has the red and Bamse the dark brown (the pictures contain the GIS data of other monitored bears).
The biggest movement dynamic was shown by Covas, a male which has been rescued from gypsies by the Covasna County Environment Protection Agency in the early spring of 2008. The cub was presenting severe injures, being bitten by dogs, being also very weak. The cub recovered fast in the Rehab Centre, making team with Bamse and Vranceanca. He has been released in June 2009, having the shape of a very good developed yearling, and a very wild behavior. The release site was Covasna County, the nearest settlement being Ghelinta, a rural village. Bellow we can see the locations and movement of Covas until the middle of November 2009.
These pictures show locations and the movement dynamic of Covas;
Analyzing closely the locations of this bear, together with the visual (aerial and terrestrial) inspection of these sites, were observed the following:
Shortly after the release, the cub roamed in the Vrancea Mountains, at SE, spending all the summer near the highest peaks of this massif. Is interesting that once interfered with the area where Vranceanca has been released. The mentioned area offered rich crop of mountain fruits and shrubs in that season, offering home range for many big bears as well.
Is interesting that in fall time (September) he left this area suddenly, coming back to the release site, and from there surrounding the depression of Targu Secuisc, he entered in the Ciomad Mountains. We received locations in the middle of September one week continually from one place. Thinking that the collar is off, or the bear is killed, our team went immediately there. The surprise was not small, when we founded out that Covas captured there a small roe deer and hid it under the ground. He spent there one week, guarding it until consumed it completely. The area wasn’t offering other crops in that time there, being mostly a birch forest, without any eatable fruits. So the bear roamed further in the Ciomad Mountains, and passing near the settlement Tusnad Bai, he moved in the Harghita Mountains. Is important to be mentioned that Tusnad Bai is one of the settlements with problem bears and garbage bears. Here are coming more than 20 bears to a nearby rubbish deposit. Covas passed near this rubbish deposit and never get close to it. He roamed on the peaks of Harghita Mountains and passed toward Mures county. Here he entered into an interesting habitat type, with small oak forests interrupted by urban villages. At the firs look would seem that he went into human settlements, but overlaying several geo referenced aerial photos and orto photos, we concluded that he was roaming between these small oak forests (which produced exceeding much fruits this year), coming sometimes at the edge of small agricultural fields (a general typical behavior of bears). He surrounded even a big city (Targu Mures), and came in the same area where Bamse actually is, in the Gurghiului Mountains.
All the movement distance of Covas is impressive: 718 km’s totally, most of this distance being made in only 2 and half months. He went at 250 km’s from the releasing site, intersecting in that period the home range of 2 other colleagues. Computing the used total home range with the method of Minimal Convex Polygon concluded that the total used area is until now near 7000 square km’s.
In opposite with this, Vranceanca moved the less among all the released bears. Vranceanca has been rescued by the Large Carnivore Rescue Team in Vrancea county (part of a Life project related with large carnivores). The cub remained orphan due to timber exploiting disturbance. She has been released in the middle of the summer of 2009 in the provenience area in Vrancea Mountains, SE Carpathians. Below we can see the locations of Vranceanca from the release moment until now. The releasing place is exactly the area with point agglomerations on the satellite view. Having lots of food sources there, she remained in the same place all the summer, and started to move toward South few km’s only in fall.
Locations of Vranceanca
Movement of Vranceanca
Is very interesting to mention, that in the up mentioned Life project, the Large Carnivore Monitoring Team GPS collared one wild bear in the same area, and in an impressive way the movement of that bear was exactly the area where Vranceanca roamed around. So it seems that bears in a certain area recognize somehow the adequate places for home ranges. The wild collared bear moved even a little closer to villages and settlements than our rehabilitated bear. The total movement distance of Vranceanca is 370 km’s since the release, roaming only 30 km’s from the release site. The calculated home range with the Minimal Convex Poligon method is 468 square km’s.
The third bear, Bamse has been brought in the Rehab Centre from Brasov county in 2008, being rescued by a professional hunter. The cub got lost from the mother and the other brothers, rolling down on a very steep mountain slope immediately after coming out of the hibernation den. The mother didn’t come for him, due to the fact that would be risking to loosing the other two cubs. Bamse was too small for climbing that slope. Fortunately the good willing man founded him, brought home and fed the cub the best he could. Bamse arrived very early in the BOS (beginning of March), being so small, that couldn’t even walk. In the second part of the summer 2009 the enclosure where Bamse was has been opened, offering the bears the possibility to go out and come in for the additional food after free will. Bamse visited the facility at the beginning every second day, but after the plum berry bushes started to produce fruits he came back less and less. Below we can see the locations of Bamse and his movement map on a satellite view.
Locations of Bamse
Movement of Bamse
In September Bamse went directly toward North, in the Calimani Mountains, a very wild area and surrounding all the Giurgeului basin came westward from the release site, until has found an oak forest and bush vegetation area with lots of crop. This area is quiet fragmented with small villages, but Bamse never approached none of them, proving really the co-existence between bears and people in that area. Is characteristic, that the bears are roaming towards these oak or beech forest sites in fall time. The fruits of these trees contain lots of oils, and the bears know that these are the most worth foods in that period for the winter fat deposit they will need during the winter sleep. All the movement distance of Bamse is until now 516 km’s, establishing presently his home range at approximately 100 km’s from the release site. The used are calculated with the minimal convex polygon until now is 3 208 square km’s.
Conclusions:
All the released bears until now behaved similar with the wild bears of the certain area. (there are available also GPS monitoring data of wild collared bears). The home ranges, habitat use and even roaming routes were observed to be very similar with those used by wild bears. The monitoring of other bears showed that in all cases the males are moving much more than the females. Females are establishing much smaller home ranges and roam much smaller distances. Bears are not territorial animals, and in food concentration periods are concentrating in small forest sites or areas.
What was very interesting is that our monitored bears never came to garbage places, even if passed several locations where wild bears did so. No one of them was seen by people, even if sometimes passed close to a small settlement or village. The monitoring team checked out every “strange” location, where there was a question sign why the animal occurred in a certain place.
Our post release monitoring experience on GPS collared bears shows realistically that bear rehabilitation is a possible thing, not affecting the wild population. Until now we never experienced nuisance behavior in our released bears.
The home range analyze, habitat use and movement dynamic of these bears showed that the bears are roaming much bigger distances than we were thinking about or the literature shares. The population estimation methods (snow track counting method) for example should be reconsidered in the management plane of the brown bear considering our monitoring results.
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