Wednesday, July 18, 2012

Day with the good news and the bad news

As it often happens – life have brought today both good news and some bad ones for balance. The morning started with rushing out half-sleeping at 5 AM – Andrus have started the standard monitoring in the southernmost tip next to the field base and very soon discovered unusual lark species next to him. I have managed to shoot first frames almost instantly then reaching the place – the bird was tame while walking for seed feeding on the ground.

By studying the photographs and  Svensson’s guidebook – we have confirmed the Crested Lark Galerida cristata – rare bird nowadays in Estonia. It was first recording in this year for the country and new species for Kihnu avifauna. This adult bird had very warn out plumage. The distinctive crest, upward pointing bill and uniformly brown outermost tail feathers have made the species ID.

After sending SMS to the rare bird network, phone started to ring pretty soon: The head of the Estbirding birder’s society and the national rare bird committee, Margus Ots have started to gather info for a rarity mission. Hi is doing the Big Year (trial to beat the mark of a annual bird species list) and was very keen to got another much needed tick to the list. Three hours later he landed at ferry from mainland and after another hour got his reward! If someone is interested on outcome of the Margus Big Birding Effort, he is keeping the blog: ; Estonian birder’s society’ have web page:

All important clues (crest, bill, tail) in the single photo

From the migration side, the day was fairly quiet. Only the 613 Great Cormorants Phalacrocorax carbo  and 410 Starlings Sturnus vulgaris have reminded, that for some species the leaving season is on. The new migratory species today was Sand Martin R. riparia – 37 individuals has been observed departing to the sea. Among seaducks, only 14 Velvet Scoters Melanitta fusca have migrated. The stones of the southernmost point have been occupied by appr. 60 staging Common Gulls Larus canus.

The gang of waders continuing to grow around the bays and shores of the island. In the western coast near the camping area the single Knot Calidris canutus and Turnstone Arenaria interpres appered as new species for the autumn season. Next to the ferry harbour, 3 Curlew Sandpipers Calidris ferruginea in the nice breeding plumage has been feeding.

Curelew Sandpiper

And the bad news part:

There are several pairs of House Martins Delichon urbica breeding in our field station building and nearby lighthouse. As they are using mud and algae form the seashore for nest building, some of the nests have fallen and broods where perished. One pair has established their nest into well supported cavity inside the roof, just next to our main door. Well chosen I have thought, good support and not accessible for predators. But today something unexpected has happened. In the early morning, everything was fine, but after returning from Crested Lark spotting, I have found one dead nestling from the concrete floor under the nest. Then heading out after coffee break, another fallen nestling was laying dead next to his mate. I become to worry – what is going on, why the helpless nestlings dropping dead out from the nest? Then I have turned back from my duties I have discovered even third sibling dead on the ground! Then I watched the situation on site, dispute between several martin individuals happened and entering of rivaling birds into cavity with nest got my attention. After this, mystery was revealed – the aggressive intruder (probably male) has made cruel infanticide!     

There is not much evidence on this kind of behavior of birds. Only one case has reported from Barn Swallow Hirundo rustica among swallows and martins. One attempt have observed by male Black Stork recorded by webcam in Estonian nest. Ecologists suggest that this might be a desperate act of violence of single unpaired males. It has explained that these individuals may hope to find their chance by divorcing a existing pairs by ruining their breeding attempt. Rare or not but nasty to witness, this proves once again, that struggle for survival is not a funny game.

Poor nestlings - are they victims of the infanticide by a desperate male?

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