Follow the Danish golden eagles
We call the two Danish golden eagles Hostemark and Tofte based on the places they were born. The male golden eagle (blue) was born in April in Høstemark Forest, Jutland, Denmark. The female golden eagle (yellow) was born in May in Tofte Forest, Jutland, Denmark.
Current status (mid January 2017):
The two young eagles met each other briefly in the area North of Hals Mose on the 17 December. Subsequently, they went in different directions and Hostemark flew back to stay in Hals Sønderskov, interrupted by a trip down to Mariager Fjord. Tofte flew to the eastern part of Bolle enge and Gettrup Skov, but due to low battery level we are now only receiving irregular transmissions from Tofte.
Mid December 2016:
Hostemark has left Hals Sønderskov and is now just north of Hals Mose. Tofte is still in the farmland north of Hals Mose, and the two birds are now only three kilometres apart.
Mid November 2016:
Hostemark is still in Hals Sønderskov, where it has been for 3 months now, only interrupted by a few short trips to Tofte Skov, Høstemark Skov and Store Vildmose. Tofte left the farmland area south of Bolle Enge, and moved to Hals Mose and farmland north of here.
Mid October 2016:
Hostemark stayed in Hals Sønderskov, only interrupted by two short trips to Tofte Skov and Store Vildmose. Tofte left the area around Råbjerg Mose after 1½ month here. Since the end of September it has been in a farmland area south of Bolle Enge, still in northern Jutland.
Mid September 2016:
Hostemark left Lille Vildmose and moved to Hals Sønderskov where it has stayed for four weeks now. Tofte left the Skagen Peninsula after three months, but it only moved a short distance south and has been staying in an area just west of Råbjerg Mose.
Mid August 2016:
Hostemark has returned to Lille Vildmose once again. Tofte is still in the same very small area at Skagen Peninsula.
Mid July 2016:
Hostemark left Lille Vildmose again and stayed in an area south of Grindsted that it also visited in both early and mid May. After a month it moved to northern Djursland, where it currently is. Tofte stayed at Skagen Peninsula, all the time within a very small area at Hulsig Hede.
Late May 2016:
Hostemark left Lille Vildmose to tour around central and northwestern Jutland only to go back to Lille Vildmose. Tofte went quickly through all of Jutland to reach the Skagen Peninsula. It was seen by birdwatchers at “Flagbakken” near the tip of the peninsula, before it moved a little further south and stopped.
Early May 2016:
After coming back to Denmark Hostemark took a trip around most of Funen before going back to Jutland and in a quick pace back to its origin in Lille Vildmose. Tofte is also back in Denmark now, crossing Flensborg Fjord in almost the exact same place as Hostemark followed by a swift migration up through Jutland.
Hostemark has started moving north and crossed the border into Denmark after nearly six months in Germany. It crossed Flensborg Fjord and is currently stationary east of Christiansfeld. After five months near Wittensee, Tofte has moved 20 km north and might also be on its way back to Denmark.
Both birds are in northern Germany. Hostemark has started exploring a new area east of Kiel near the lake Selenter See. Tofte has remained near lake Wittensee.
Tofte is spending her time near lake Wittensee, while Hostemark is further north in the areas of Winnemark og Waabs. The gps signals have picked up and are now sending data back more frequently. The last couple of weeks of more sporadic data, was most likely due to insufficient solar panel recharging
The birds fly south through Jutland to Germany in different pace and along seperate routes. They seemed to join up in the same area between Sleswig and Rendsburg.
October 14th 2015:
Both birds leave their home territory. Hostemark may have attracted Tofte to leave as the birds flew together for the first 5 km.
The eagles stay almost exclusively within the forest in their home territory.
Golden eagles in Denmark
The golden eagle started breeding in Denmark in 1998 and the population now seems stable with three breeding pairs. Since 1998, a total of 34 juveniles have successfully fledged. Of these, 15 have been ringed but excect for three, the destiny of the birds remains unknown.
Why are we tracking them?
In a new Danish research project, we are tracking juvenile golden eagles with GPS technology to understand their movement patterns and use of non-breeding areas. The technology allows us to explore their habitat use and home ranges across the annual cycle. The information we gather will help determine the source population to the Danish breeding birds and investigate genetic relationship within the Danish population. The birds have already shown a large individual variation in movement.
How do we do it?
We mounted a GPS/GSM transmitter to the juvenile golden eagles while they were still in the nest, using a near-adult size to ensure proper adjustment of the harness. The transmitters are mounted with a body-harness following the same technique as has been used on golden eagles in e.g. North America and Sweden. The transmitters are charged by a solar panel and will in theory work throughout the lifetime of the bird. A GPS-position is stored in the transmitters every 15 minutes and sent back via the GSM-net once a day.
Anders P. Tøttrup, firstname.lastname@example.org
Jan Tøttrup Nielsen, Kasper Thorup and Cellular Tracking Technologies. The project is in collaboration with the Copenhagen Bird Ringing Centre at the Natural History Museum of Denmark. The project is funded by Aage V. Jensen Naturfond