Male Osprey M-41384 ”Sarsa”

The male Osprey ”Sarsa” was caught on 4 Sept 2003, when he was hunting at Kangasala, at the ”service pool” of the Pohtiolampi Osprey Centre. Sarsa was given the id ring W5 and the same 30 g battery transmitter (manufactured by North Star) that had visited Sierra Leone a year earlier on the back of ”Victoria”. Timo Laine had ringed Sarsa in the summer of 1999 as a nestling in a nest at Orivesi, 26 km from Pohtiolampi.

Autumn migration 2003

Sarsa started his migration late, but was in a hurry once he got started. On 16 Sept at 10.51 o’clock, Sarsa was still two kilometres from Pohtiolampi. The following evening at 23.49 he was already in Belorussia, 866 km from Pohtiolampi. The following readings came from the Ukraine, 57 km south-southeast from Chernobyl (19 Sept), and from Romania, 58 km northwest of Bucharest (21 Sept). After travelling 2168 km in a week, i.e. 310/day, Sarsa paused for four days (23–27 Sept) in Bulgaria, in the valley of the river Maritsa, 60–120 km southeast of Sofia. His last reading from Europe showed us that Sarsa stayed the night 28–29 Sept in Greece, at the tip of the Kassandra peninsula that sticks out in the Aegean Sea, 77 km southeast of Tesssaloniki.

At most, Sarsa spent 41 hours on flying the 1174 km from Kassandra to Cyrenaica in Libya (30 Sept). This means that he made an average of at least 29 km/h. i.e. 687 km/24h. After that, he immediately crossed the Sahara, following the exact same migration route by Libya (30 Sept–2 Oct) and Chad (2–6 Oct) to Cameroon (8 Oct– ) as did Marjaana and Lea, for example. in autumn 2002. The Sahara/Libya desert leg of the journey was approximately 1960 km long, and Sarsa covered that in five days, averaging 392 km/24 h.

On 9 Oct, Sarsa arrived in his wintering area at the Moinum river in Cameroon, at the shores of which the young female Osprey Mirja has been fishing since the beginning of February 2003. The total distance of Sarsa’s flight from Pohtiolampi to the Moinum river was 6572 km. If Sarsa had taken the shortest route possible, his voyage would have been 301 km (i.e. 4,6%) shorter. Sarsa’s autumn migration took 23 days, of which 19 were actual flying days. The speed of his migration was 286 km/24 h on an average, and on the actual flying days it was 346 km/24 h.

Winter 2003-2004

During the period 9 Oct 2003 – 22 Mar 2004, we had as much as 304 readings on Sarsa, with an accuracy of at least one kilometre. They showed very clearly that Sarsa had spent the winter by the Moinum river, in an area of only 87 km2, located 150 km west-southwest of the Tibati reservoir and 288 km north-east of Douala, a city at the head of the Gulf of Guinea.

Spring 2004

Sarsa started his spring migration on 23 March. On 22 Mar, he was still in his winter abode, but the following night he spent on the northern slopes of the Adamawa mountain, 180 km from the Moinum river. The following, and unfortunately, the last, readings came in on 27 Mar from northern Cameroon by the border to Chad at noon and from Chad in the evening, 233 km south-west of the capital, N'Djamena, and 53 km north of the Chari river. At that time, he had only covered 820 km of his return journey.

In this case, it is almost certain that the transmitter failed due to a programming error. The ‘winter rest' for saving batteries was supposed to remain the same when the transmitter battery was changed. This means that the pause between the 8-hour transmission periods was supposed to be 84 hours instead of the 36 hours during the migration. This was clearly not accomplished, because readings on Sarsa were received at the same frequent intervals all through winter as during his autumn migration, which led to the battery dying in the midst of the spring migration.

Summer 2004

Sarsa, with a mute transmitter on his back, was first observed at his nesting area on 18 May. Though we had several readings from Sarsa during the summer, we could not catch him, because a raven (?) destroyed his nest at the incubation stage. Like Laho, Sarsa will have to wait until the threads fall apart or we try to catch him next year to get rid of his rucksack.