Finnish Museum of Natural History
Satellite Osprey Jukka
In summer 2009 the project, started in 2007 in collaboration between the Finnish Museum of Natural History, the Osprey Foundation and UPM, continued monitoring the life of a male Osprey with the help of the newest generation of GPS-Argos satellite transmitters. Professor Pertti Saurola continues as the scientific director of the project, and is in charge of the results and writing presented on this site.
In summer 2007, we gained a great deal of detailed information with the help of the new generation of GPS-Argos satellite transmitter fitted on Pete, a male Osprey. The data included (1) the size of Osprey fishing ranges and especially how significant the supply of rainbow trout at the Osprey centre in Pohtiolampi, 15 kilometres from Pete's nest, was in Pete's diet; (2) information on the autumn migration which revealed, among other things, that Ospreys also migrate during the night; and (3) the extent of the wintering range. Unfortunately, Pete perished in April 2008 in Morocco, on his way back north.
In August 2008, Pete's remains and the transmitter were found in the desert sands, with the help of the readings from April and a search party organised by BirdLife. When the transmitter arrived in Finland, we discovered that its battery could no longer recharge itself from the solar panel. The transmitter was returned to the manufacturer (Microwave), where it received a new battery. This made the transmitter functional again, and ready to be fitted on another Osprey.
In spring 2009, we decided to continue collecting Osprey data with the same aims as in summer 2007, i.e. to gather information on the significance of the Pohtiolampi Osprey haven as the fishing range of Ospreys in the vicinity. Now we wanted to fit the transmitter on a male with a nest some 20 km from Pohtiolampi.
For various practical reasons, we did not manage to catch one before the fledgling stage on 31 July. At that time, Juhani Koivu, Harri Koskinen, Pertti Nikkanen and Helmi-Irene Saurola managed to catch a male Osprey weighing 1,350 grams at Äimälänniemi in Pälkäne. He was given the 'human' name Jukka after Jukka Syrjänen, who has worked at the Pohtiolampi Osprey centre for many a summer. The nest of Jukka the Osprey is located 19.7 km from Pohtiolampi, in a forest area previously owned by the Syrjänen family.
Unfortunately, we do not know anything about the past, i.e. birth date or location, of Jukka the Osprey. Ringer Harri Koskinen registered Jukka only now, as an adult, into the ring register under his 'official name,' M-59925. In addition to the aluminium ring attached to his right leg, Jukka received a red ring with the code PS engraved in white on his left ankle. The function of the transmitter remained the same as when Pete carried it.
Jukka's nest is in an excellent location for the study of the significance of Pohtiolampi. Firstly, the shortest route flying from the nest to the Pohtiolampi rainbow trout basin goes over the Mallasvesi lake and the rich natural fishing of the Roine lake. Secondly, the Tykölänjärvi lake, known as a traditional Osprey fishing range, is only a few kilometres from the nest. Thirdly, there are only around five kilometres from the nest to low bream shores of Pintele and less than ten kilometres to those of Vanajanselkä and Ilmoilanselkä. Pete the Osprey was a regular visitor at Pohtiolampi. Was it a good idea for Jukka to fly the 40 km return trip to Pohtiolampi to find more fatty rainbow trout than the natural fish in the bountiful vicinity of his nest?