Risnjak pack

Risnjak pack

The Risnjak pack spends the majority of the time in the area between Crni Lug, Delnice and Lokva, but also appears on the other side of Mt. Risnjak – the Lazac meadow, Vilje, Suha Rečine and Gornje Jelenje. This area is 120 km² in size. The first wolf to be considered a member of this pack was the female Hilda, who was collared during 2002 when the Risnjak pack had six wolves, though during the winter 2002/2003, that was reduced to four wolves. In winter 2002, another female was collared, i.e. a young wolf, seven months old, named Blaža.


Beginning from summer 2004, the Risnjak pack was monitored through female Tanja, the reproductive (alpha) female of the pack who was collared in September. The previously collared Hilda and Blaža are her offspring. To the end of 2004, the territory of the Risnjak pack was 140 km² in size. During winter 2004/2005, snow track monitoring established that the Risnjak pack had at least four, and likely five wolves. Monitoring during spring and summer did not give any definite data as to whether there was a litter in that pack in 2005. Tanja had the same movements as in winter, was in a different place every day, occasionally up to 15 km away from the day before. The lack of a constant place to where the female would return (den/gathering area), and the lack of findings of other signs (intensive markings of the territory, howling of young wolves) confirmed that there was no litter in the Risnjak pack in 2005. Tanja also moved in new areas, such as around the spring of the Kupa River, the Kupica Canyon near Delnice, and it is also interesting that she was on the southern side of the motorway, on the Sopač hill. This implies that this pack has succeeded in finding a crossing over the motorway. This has raised the territory of the pack to an area of 193 km².


Considering that few signs of wolf presence were recorded during 2005/2006, in 2006 no intensive research was conducted on the Risnjak pack. There were also no plans to capture new wolves in this pack's territory, as the likelihood of a successful capture was assessed as negligible. However, it was learned that the pack reduced its area to 160.3 km², which is in line with the fact that the number of wolves in that pack has declined in the past year (only two wolves during winter 2005/2006). In winter 2006/2007, track monitoring showed the presence of four wolves in the Risnjak pack, likely dispersers from surrounding areas who have re-established a pack here, after it was temporarily empty, either partially or fully, during 2005/2006. In summer 2007, multiple signs of wolf markings were observed, which was confirmed by the capture of the female W19-Rina. Rina remained in the known territory of the Risnjak pack, with a slight increase of that territory, mostly with the area between the old road and the motorway. The territory of the Risnjak pack, calculated by monitoring Rina over the course of 401 days, was 318.9 km2. The data obtained for the pack for 2006, through the monitoring of the female wolf Tanja, was 160.4 km2. This difference could be the result of a smaller number of individuals in the pack that year, but also due to the fact that Tanja was monitored only using a VHF collar, and part of her movements remained untracked. The Risnjak pack had successful reproduction in 2008, which was confirmed with the find of seven cubs in spring 2008.


The research was continued during 2009 and on 19 September 2009, a female wolf 3.5 years old and weighing 26 kg was captured and fitted with a GPS collar. This was wolf W19-Rina, a member of the Risnjak pack, who had previously been fitted with a GPS collar, but which had stopped operating, i.e. no longer emitted a signal. With her re-capture, Rina's collar was replaced. Monitoring snow tracks during winter 2009/2010 resulted in the observation of at least six wolves in the territory of the Risnjak pack. During that period, Rina was 5-6 years old and a constant member of the pack that remained within the previously known boundaries of the Risnjak pack. With her second collar, a GPS-UHF collar, she was monitored for 1011 days, with a total of 5494 locations. Rina's last location was recorded on 6 August 2010, at which time no further signals were emitted from the collar.


The Risnjak pack had successful reproduction during 2010, which was confirmed with trial howling and the observation of one pup from the litter. The size of the range area of Rina and the Risnjak pack during 2010 was 368.8 km². Six wolves were counted in the pack, giving a density of 1.63 wolves per 100 km². During winter 2011/2012, five wolves were recorded in the Risnjak pack, while during August 2012, no signs of wolf presence were observed.


In April 2013, female wolf W28-Tona was found in the territory of the Risnjak pack, in the company of three other wolves, when the data were downloaded from her collar. It was established that Tona had spent the majority of the time in Slovenia, and her movements covered the territories of three known packs (two in Croatia and one in Slovenia). Her movement range was 1169.8 km². In August 2013, her abandoned collar was located at Crni Lug.