ארכיון יומן של מאי 2020

מאי 22, 2020

Common Cuckoo egg laying and stealing egg from host species

Yesterday I witnessed a spectacular event. Something you normally only read in text books, but never expect to witness yourself... I saw the brood parasitism of a Common Cuckoo, happening live in front of my eyes!

Cuckoos show brood parasitism, which means they don't care for their youngs themselves, but use a host instead. The host can be different species of Passerines (in my case it was a Meadowpipit). This way of "breeding" means the cuckoos have to fool their host (the foster parents for their chicks) to be succesfull. If everything goes well for mommy cuckoo, the host species raises the cuckoo young as its own... (and in the end it will lead to a horrific scene, where the cuckoo young will kill its stepbrothers and sisters, to get all the food for itself).

There are many moments in the life of a cuckoo where things can go wrong. And cuckoos keep adapting to win this race. E.g. their eggs mimic the eggs of the host species: if eggs look more similar they stand a better chance for acceptance by the host species. Find out more about these adaptations in the wikipedia article: https://en.wikipedia.org/wiki/Common_cuckoo

So what did I see? I saw a female tracing a nest of a Meadow Pipit and then she was laying her egg inside this nest. She scanned the area and then entered the nest. The Meadow Pipits were around and alarming when she took her chance. What happens after egg laying? Well, in a nest of, let's say 4 eggs, there can't be suddenly 5 eggs. That would be suspicious, right? And this extra egg might alarm the host, to get rid of this devilish egg or even abandon the nest. So the Cuckoo female has a cunning plan, to trick the Meadow Pipit! She removes one of the eggs, to replace it by her own! And exactly that is what you'll see in my pictures! Check the beak! She removes one of the eggs from the nest and carries it in her beak! Isn't that remarkeble?!!!

I was stunned!

Common cuckoo laying her own egg and stealing egg from host species

פורסם ב מאי 22, 2020 09:06 לפנה"צ <span class="translation_missing" title="translation missing: he.by">by</span> wouterteunissen wouterteunissen | תצפית 1 | 2 תגובות | הוספת תגובה

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