What happened to Mark and Madge, the Montagu's harriers we were tracking on their migration from the UK to Africa? Ben Koks and Almut Schlaich, from the Dutch Montagu's Harrier Foundation, have exciting news...
Tracking birds with satellite transmitters is still bringing us new insights in wildlife ecology. In 2014, the RSPB and the Dutch Montagu's Harrier Foundation organised the tagging of three adult Montagu's harriers in the UK.
The main objective of this particular part of our work is not only to find out more about the migration of Montagu's harriers, but to gain a better understanding of where they 'stopover' and spend winter. For this reason, we started doing fieldwork in countries like Niger, Mali, Burkina Faso and Senegal in 2006. We also visited eastern Morocco, an important stopover site, four times in 2010 and 2011.
We wanted to see with our own eyes what happened to 'our' birds. Rather than waiting for the satellite coordinates, we went and found the birds! This combination of high-tech and old-fashioned fieldwork is necessary to understand Montagu's harriers in greater detail. Another major objective was to find out where deaths occur. Without satellite tagging, this would have been impossible.
When we received an enthusiastic invitation from Mark Thomas of the RSPB to be part of an exciting workshop about the conservation of Montagu's harriers in the UK, we replied in a split second with a thrilled 'Yes'. Later in 2014, together with Mark and some of the other dedicated British Monty's fieldworkers, we caught and tagged three adult birds. One male ('Mark') and two females ('Mo' and 'Madge'), all funded by Mark Constantine at Lush.
We know that Mo did not even start her migration because in August she died in circumstances that sadly suggest illegal persecution. We knew about the killing of hen harriers in the UK but we were not aware that Montagu's are under pressure because of illegal persecution here, too!
After their departure from the UK, Mark and Madge started their autumn migration in the last week of August, and on the RSPB website people can follow their journeys.
It's always exciting to see how they do it. Madge reached Senegal on 23 October. Mark arrived in his first wintering area in Mali on 4 October, then headed to Senegal on 7 November and finally reached his second wintering area on 10 December. So far so good.
Both birds seemed to stay in their wintering areas, but just before Christmas we saw that though Madge's transmitter was still sending data, she was not moving anymore. In other words, Madge died at that time.
During our fieldwork in Senegal we visited the wintering areas of Mark and Madge. We arrived in Madge's area, near the village of Ndiaouara, on 29 January. Not far away from the Gambian border, at Madge's last-known location, we found a small roost of six Montagu's and six marsh harriers. This is a typical type of wintering habitat of many Monty's in western Africa.
We saw during our regular grasshopper counts that there was plenty of food in this area, so this could not be the cause of Madge's death. It's possible she was killed by a jackal or Verreaux's eagle-owl - these are both predators of Montagu's harriers and were present in the area where Madge died.
Madge was already an 'old lady' during her last breeding. We spent almost a day trying to find Madge and her satellite tag with the help of local boys, but we were unsuccessful. The vegetation was too high and too dense to find a tiny, 12g device in an area of one squarekilometre. We left our contact details in the hope the transmitter will be found by someone in the future. Fingers crossed we get some news when we return to Senegal again in March.
Looking for Mark was totally different. First of all, we knew that this male was still alive but we had to tackle at least one problem. We knew that he was roosting on a small island called Gaye, but we had to organise a safe trip there. Using our contacts we made our way to a small village called Ndiol and found a fisherman with a good motor on his pirogue (fishing boat) to take us to the place where we thought our British hero was roosting regularly!
We found a roost of at least six harriers there on the evening of 5 February and planned a trip the next day. On the 6th we had enough time to visit the rich and beautiful island, collect more than 70 regurgitated pellets (with an average of 10 prey items per pellet). And, best of all, we counted a total of 26 Montagu's harriers at Mark's roost! Unfortunately, we didn't see him, but we were still very satisfied with our work - with the bonus of five magnificent short-eared owls hiding under a small tree.
Going back to our own roost, after eating dinner we checked our photos and discovered to our great joy that we had photographed Mark! He had been too far away for us to see his tag's antenna, but the camera caught this most important evidence. We had found Mark in his main wintering site, he was safely surrounded by water and we once again had a new piece of the puzzle of harrier ecology on two continents.
We have just arrived back home in Holland: we collected information about at least 7,000 prey items from 12 roosts, counted the biggest harrier roost ever (4,000+ Montagu's harriers), proved again that wintering short-eared owls are quite regular in the Sahel, met a lot of people, kept our four-wheel drive running. And we learned a lot about 'our' migrant birds and their place in rapidly-changing landscapes in this part of the world.
Satellite transmitters connect these worlds to each other and we hope to report more results from further fieldwork in this stunning region of our globe very soon.
Guest blog by RSPB Senior Conservation Scientist Dr Steffen Oppel
Four vulture species breed in Europe, and the smallest species, the Egyptian Vulture, is the one with the most precarious conservation status. Just how desperate the population status of Egyptian Vultures is in eastern Europe was recently revealed by a study published in the journal Bird Conservation International.
Egyptian Vulture decline of about 7% per year
A large group of collaborators from Bulgaria, Greece, Serbia, Albania, Turkey, and the former Yugoslav Republic of Macedonia compiled all survey data from the Balkan peninsula from 1980 until 2013. The team, led by Metodija Velevski of the Macedonian Ecological Society (MES), and supported by RSPB Conservation Scientist Steffen Oppel, found that the population had declined from almost 600 pairs in 1980 to less than 100 pairs in 2013 – a decline of about 7% per year! That is the equivalent of the UK losing the human population of a city the size of Brighton, Leicester or Cardiff every year!
Egyptian vulture (Neophron percnopterus) by Béotien Lambda
Disappearing from regions and countries
During this period, Egyptian Vultures not only declined in numbers, they also disappeared from entire regions and countries. The documented declines are however just the tail end of a decline that began many decades ago – before anybody tried to systematically count vultures. Egyptian Vultures no longer occur in the Ukraine, Romania, Croatia, Bosnia and Herzegovina, Montenegro, or Serbia, and the few remaining pairs in Greece and Albania are struggling to hold on.
Why are Egyptian Vultures in desperate trouble?
A large project in Bulgaria and Greece is currently trying to understand the causes of population declines. Because Egyptian Vultures migrate to Africa every year, they are exposed to a wide variety of threats both in Europe, along the flyway, and in Africa. Many birds get killed accidentally by consuming poisoned carcasses that were intended for other animals, by landing on poorly insulated power lines that electrocute birds, or by being shot for pleasure or market trade in Africa. Some progress has been made in the project, for example a dangerous power line in Sudan, which killed hundreds of vultures over decades, has recently been disconnected.
Calling for a ban of vulture killing drug in Europe
Despite conservationists working intensely to understand and reverse population declines of Egyptian Vultures, conditions are not necessarily improving: the EU has recently allowed a veterinary drug that his killed millions of vultures in India and Nepal (and has been banned in these countries!) to be used for cattle in Europe – despite repeated warnings by scientists. You can help vultures by telling the EU to ban this lethal drug and hopefully avoid yet another threat that will accelerate the decline of vulture populations in Europe.
How you can help:
Sign the Diclofenac petition
[The spoonie team are back from Myanmar, so Nigel Clark has provided an update]
We are just back in Yangon having spent the last 8 days on an expedition to resurvey the waders that winter on the upper Bay of Martaban. The team consisted of Nigel Clark from the BTO, Guy Anderson, Graeme Buchanan and Rhys Green from the RSPB, Geoff Hilton from WWT and five ornithologists from BANCA (the organisation in Myanmar that has taken on the task of saving spoonies in the country). To get the 10 of us out into the middle of the estuary for a week required a fleet of 7 boats, each about 6 foot wide and 25 foot long and 14 experienced local boat handlers.
Living in these conditions for a week is a strange experience. The boats settle down on the flats on every falling tide in places where the boatmen know are away from the tidal bore that comes in on every tide. This means that they are also areas where a lot of soft mud settles. As a result mud gets everywhere if you are not careful to clean off the clingy mud every time you get into the boat. Remarkably the cooks managed to produce fantastic local food on tiny simple charcoal stoves in the bottom of the boat.
Our days were governed by the tides and as soon as the tide went out we would fan out from the boats to survey the mudflats looking for flocks of small waders when we found one we would count the number of each species and hope to find a spoonie before moving on to the next flock. We did this for up to 7 hours a day traveling a total of 6 to 15 km a day but making sure that we were back close to the boats before the bore arrived! Luckily that boatman could predict it well and gave us a time that we must be back so we were close to the boats long before the bore arrived. This also meant that we could observe bird movements on the rising tide and assess the total number of birds in the area.
Time and tide wait for no-one (Guy Anderson)
So how did we do? The results were simply staggering! When we added up the totals of each species each day we counted a total of 145 thousand bird days. Taking into account the days when we might of counted birds seen on other days we believe that the minimum number of birds in upper Martaban is 90 thousand which is a substantial increase on previous counts.
We also had a total of 184 sightings of spoonies most of which were in scan samples where we counted all the waders in each flock. A rapid analysis by Rhys suggested that there may be about 155 in the upper bay now which is a similar number to previous surveys. This is very encouraging as we had predicted that the population was declining by 26% per year. If that was still happening then we would have only found 40 or less.
The big surprise was that we only found one colour marked bird which on first sight seems different to the proportion marked in the surveys we did in China in the autumn. This could be just chance or could suggest that there is some population segregation going on. We need to do a full analysis before we can decide which is the case, but it does show how difficult it is to understand the movement patterns of this charismatic species.
It is now time to catch up on sleep and prepare for the long flight home, but it is less than that flown by a spoonie each year!
Searching for spoonies (Guy Anderson)