It is now a week since we've had a signal back from Leri. It has come to that horrible 'inconvenient truth' time, when we have to say that Leri has most probably died.
It didn't look good a week ago when her transmitter was sending back signals with a recurring 'activity reading' number, meaning that the transmitter wasn't moving from one place to the next.
This '110' number is randomly generated and should be different for each position
On October 22nd, Leri started to move south from the area she had been in for around two weeks, on a tributary of the Senegal River. By the 24th, she had flown around 12 miles south and was in the Three Marigots water system near Mengueye. It was at around 4pm on the 24th that we think she got into trouble.
Leri's transmitter weighed just 30g and was state of the art technology - these trackers didn't exist just five years ago even. Yet, for all their incredible data-gathering capabilities, one thing they cannot tell us is the condition of the bird itself. Was Leri getting weaker as she continually looked for better fishing grounds? We know that a lot of these water bodies and tributaries dry up at this time - well established ospreys have acquired the best fishing spots and will out compete this summer's juveniles. Frédéric's recent email states that he saw eight or nine ospreys in this area a few days ago, most of them juveniles - it seems clear that this area is not preferred by adults. Frédéric also mentions old fishing nets and hooks in the water within this area; could Leri have got caught in these and perished? No meaningful data came in for October 25th and 26th but the activity number reading was not changing, still showing 110. The last confirmed GPS readings were sent on October 29th with some other data on the 30th. Nothing has been sent since.
The statistics are known: only one in three or four ospreys ever make it back to the UK to breed. By 2011, the Glaslyn osprey nest, just 28 miles away from the Dyfi nest, had produced 12 fledglings that were old enough to have returned to the UK, yet only two have so far been spotted. Yes, there may be others that we haven't managed to identify, but it still looks no better than one in three/four probably. We are learning all the time, of course. This is the first time that Welsh ospreys have been satellite tracked, and we already know that being so far west probably does not negatively affect their initial course and predispose them to fly west into the Atlantic, something that we had worried about for a long time. We have also learnt from this and other osprey tracking projects in the UK that the success rate of the first migration to west Africa is relatively good; in many cases it's the increased dangers the birds face once they reach their final destination in Africa during their first winter that seems to be the bigger threat.
Knowing the stats and applying science to Leri is fine, but it still does not take the hurt away, of course. Protecting those three eggs in April and May with a team of dedicated volunteers 24 hours a day for six weeks, watching Leri hatch live on that magical Tuesday in June, and then grow up and fledge before finally migrating on the 13th of September, the last of all the family to go, is still hard to take. Roy Dennis has just arrived in Senegal and will concentrate now on trying to find and film Leri's two brothers, Einion and Dulas. The boys seem to have found better fishing areas and look settled. We hope he finds them, of course - will they be in good condition?
The Montgomeryshire Wildlife Trust would like to thank all of you for your interest in the Dyfi Osprey Project, particularly during the last week with all of the concern over Leri. We would also like to thank Frédéric for all his hard work in trying to find Leri for us. Merci Frédéric.
