Dark morph Marsh Harriers
Since the start of the count we have seen a lot of Marsh Harriers. At least 16 of them were adult males of the rare dark morph. In former years only a handful of dark birds passed the stations. Little is known about this morph, e.g. where it originates from and what percentage of the population shows this plumage. Forsman (1999) noted that this morph comes from more eastern populations and migrates through the Middle East.
Photo by Albert de Jong.
Adult males can be rather easily distinguished from the Western European plumages of the species. They show a dark brownish colour, a distinct white distal part of the remiges and a dark greyish area in the upper secondaries. Second calendar year males can be sometimes tricky to identify, but they show a more light brownish colour, yellow crown and less contrast in the secondaries. Females and juveniles of this morph are expected to be hard to distinguish.
Compared to the numbers that has been reported from Israël (on average 2-3 every autumn), our number of this autumn is already interestingly high. Do we have a lot of eastern birds this year, has the morph been overlooked previously? There is still a lot to figure out.
African-Eurasian Day Record: 179,342 Honey Buzzards
Few days ago on August 30th we were happy to report to you our all time record of 99,000 Honey Buzzards passing our observatories. With that BRC record set, the whole team was sure to have experienced the biggest peak of the season; and given the favorable flight conditions and steady migration over the last week, the last thing we were expecting was to set the mark even higher. But so we did … and how! With a day total of 179,342 Honey Buzzards yesterday (September 3rd) we shattered the previous autumn migration world record which was set in 1982 at Israel’s Northern Valleys. It was an astonishing flight and anyone witnessing it rightly felt privileged to be here.
Photo by Albert de Jong.
The complete surprise with which the flight arrived made the whole experience even more overwhelming. As we left our headquarters in the early morning, we noticed a completely overcast sky, holding little promise for good migration. However at 7:30 the first significant flocks of Honey Buzzards were already airborne, and it did not take all that long for the counters to realize that yet another great flight was taking shape. The morning hours of furious clicking, identifying and recording flew by in a daze, and before we realized what was really happening, the legendary hurdle of 100,000 birds was tackled. We could only stand there in amazement, wondering what on earth was going on whilst doing all we could to keep up with the endless streams of buzzards. At around 15:30 some drizzle started to come down over Batumi, which gradually turned into a more steady rain that eventually grounded all the birds. Though it stopped us from reaching an even higher number, it did make for yet another spectacular sight as the treetops on the ridges were quickly covered with roosting raptors.
Photo by Albert de Jong.
Photo by Albert de Jong.
Apart from the Honey Buzzards, the harriers were going at in great numbers already shortly after sunrise, exceeding 500 birds in the 1st morning hour. These were following the major harrier flight of earlier this week, with totals of 2,136; 3,944 and 2,174 Montagu’s and Pallid Harriers on Aug 30th, Sept 2nd and Sept 3rd respectively. And yes, also these numbers make for an absolute world record!
Due to the rain putting an early halt to yesterdays massive flight it was to be expected was a fantastic migration day. No less than 60,741 Honey Buzzards were seen from the observatories today (Sept 4th), and again they were starting to kettle already very early in the morning. As the day progressed we were now taken by a wonderful diversity of raptor species, whereas the flight yesterday was entirely dominated by Honey Buzzards, with hardly an eagle to be seen. Honey Buzzards are known not to care too much about a bit of overcast sky. They are strong flyers and will only really stop flying if rain forces them too. But today, the sun was shining, thermals were strong and with these conditions came loads of other raptors that are much more dependent on good thermal soaring opportunities to cover significant distances. So the Honey Buzzard flight was joined by 3,368 Black Kites, 658 Booted Eagles, 225 Marsh Harriers, 17 Lesser Spotted Eagles, 8 Steppe Eagles, 2 Egyptian Vultures and 2 Peregrines. But the cherry on the raptor cake were beyond any doubt the 2 adult females Crested Honey Buzzard, one for each of our observatories respectively. The Booted Eagles in particular, are a very high number being this early on the season, and also represent one of the highest day totals recorded at BRC in the last 5 years.
Photo by Albert de Jong.
With the spectacular number of the past days, our annual total of Honey Buzzards has now come to a staggering 575,770 individuals. This exceeds our previous record already by nearly 100,000. And who knows what is yet to come? Overall 606,640 raptors have been recorded so far, and we look forward to counting –hopefully- many more coming our way!
Keep your eyes on our website for more delicious news to come! We will keep ours on the sky ensuring you won’t have to wait for such news very long ;-)
Your BRC Team
New day record count in Eilat, Israel, with 250.000 !!!!! on 2nd May 2015
Day record of 99.000 Honey Buzzards on 30th August 2012
Photo by Albert de Jong.
That the unique convergence of migratory raptors in Georgia is much determined by the weather conditions in the region is something the BRC team has realized for a long time. Rain events, often lasting several days along the Black Sea shore, regularly inhibit migrating birds to travel here. And rather than circumventing these bad weather events over the inland of the Caucasus, most of the raptor species observed here tend to pile up in huge numbers to the north of bad weather events, finally arriving in enormous numbers at Batumi, as soon as conditions have cleared. We have regularly observed this migration behavior ever since the start of our monitoring activities in 2008. This topic has been/is being investigated intensively in the BRC research group, particularly to better interpret the numbers of migrating raptors observed at our site for monitoring purposes.
Photo by Albert de Jong.
However our observations of two days ago on August 30th surpassed the expectations of even the most experienced counters currently working in Batumi. After one day of continuous hard rain on the 29th, where hardly a migrating bird could be spotted, a record-breaking number of 99,038 Honey Buzzards out of 102,293 raptors appeared out of nowhere above our observatories; an astounding number by any measure. The count was even more astonishing as in the week preceding the rain event we had already observed Honey Buzzard migration exceeding 150,000 birds. It is hard to put to words the awe that overcomes you when confronted with such a tsunami of birds. Quite frankly, one should just be here to have any sense of what such numbers really mean. It is magical to feel excitement build among the observers with the ever increasing numbers collecting in vast kettles over the Kobuleti plains to the north … Huge towers of raptors, growing up to several 1000's of birds strong and several 100's of meters in height. And when finally the never-ending stream of birds arrives overhead, and when you hear the tally counters clicking like mad and see your fellow observers laughing -nearly hysterically- with hardly any time to eat, that's when you know what the Batumi craze is all about. As far as natural spectacles go, the migration in Batumi must be one of the most thrilling in the world.
Photo by Albert de Jong.
Why the species has arrived in such huge numbers over such a short period of time this early this year is hard to tell without careful investigation. We expect at least some involvement of the weather conditions involved in triggering the start of migration on the breeding grounds, as well as the overall flight conditions en route to Batumi during the week(s) preceding our extraordinary count.
Photo by Albert de Jong.
We like to note here that our latest observations are in strong agreement with the outcomes of Jasper Wehrmann's Msc. thesis at the University of Potsdam, who is investigating the influence of regional weather patterns on Batumi migration. The same is true for another avenue of BRC weather-related research coordinated by Wouter Vansteelant (University of Amsterdam). In accordance to the latter research, Honey-buzzards and other soaring migrants are currently clearly being observed to shift their migration routes within the Batumi bottleneck coastward in response to strong cloud development over the Pontic Mountains in the local subtropical climate. The publications of these investigations and their conclusions with respect to the ongoing monitoring activities at BRC are expected later this year.
Photo by Albert de Jong.
Getting back to the birds we should not forget to mention the other beautiful travelers we enjoyed observing in the last days. Because accompanying the astonishing horde of Honey Buzzards, there were also 1,390 Montagu's and Pallid Harriers, 180 Marsh Harriers, 51 Booted Eagles no less than 335 Rollers and a sky full of non-counted birds including Turtle Doves, Bee-eaters, Golden Orioles and so on. With 881 Black Kites on the 30th we can also say that the migration of this species has now started for the season, and as if all of this is not enough we were still counting over 30,000 Honey Buzzards yesterday and significant numbers of Pallid Harriers on which we will be reporting later. Because at this very moment (2PM on Sept 1st) this author is seeing a flock of 20 Montagu's Harriers and a few hundred Honey Buzzards approaching … Back to count! Stay tuned for more news during the coming weeks and months. Batumi migration is as always full of surprises and causing much excitement … and we don't expect that to change anytime soon. ;)
Photo by Albert de Jong.
Photo by Albert de Jong.
Photo by Albert de Jong.