torsdag 30 april 2015

Day 18

It is Day 18 for Rickard and None's chicks and maybe the end of close-ups.
Sharp alarm calls fill my ears as I enter the experiment room with my camera.

Quickly I fire off a few shots, since I have already stirred the parents.

I try a different, safer view - and yes - the chicks have now grown so big that they are visible from outside the aviary.

Siden and Juno have been happy without my camera, and this is as close as I can get. Well, that is not entirely true. When I built their new nestbox, I put a plexi glass in the ceiling, and the ladder is still up...but I am not going to try.


torsdag 23 april 2015

Day 12

It is day 12 and the chicks have already started to open little slanted eyes. One cannot help but marvle at the astonishing growth rate.

Out of six eggs, five hatched, or maybe one chick didn't survive the fierce competition.

It is a pity that I have to press the camera button blindly, but the nest is too far up for me to be able to see what I am aming at. And I need to be quick. The parents do not approve of me coming too close - let alone the black enemy in my hands - and Rickard has already started to fluff and make short, sharp alarm calls.

So I retreat to my corner by the door, and None comes up to fill her pouch. Still wary.


måndag 20 april 2015

Food preferences

Every year, it's exciting to witness the feedings of the chicks. And this year I can even watch without binoculars. As I have blogged about before - the small chicks only get high value protein - preferably red meat, chicken, shrimps and eggs. Pork is ignored and also minced meat from ox - mayby they judge by the colour? For the parent's sake we also give some of the usaul stuff, like vitaminized dog kibble and leftovers from our dinners, and as the chicks grow older they get a wider variety of food.

So most of the time, we just hand over big chunks of meat, half chickens and eggs and let the parents do the work. But one manmade thing they DO like is this cottage-cheese-mix.

The cottage cheese is low in fat and rich in proteins, and I add a few eggs, crushed egg shells and some vitamins. Like a parent trying to sneak unwanted wholesome veggies into the food, I also add some grated apple. This is something we learned on a course in wildlife rehabilitation - apple is a good substitute for vitamins for most animals.
I believe that the ravens make the best choices for their young, but it makes me happy to watch the parents efortless scoop up the mixture in their beaks and pouches and fly off to feed their nestlings - without the tiresome job of tearing to pieces or adding saliva and water.

And it looks a bit like ris á la Malta with saffron, doesn't it?


fredag 17 april 2015

New paper on causal intervention in corvids

Ivo Jacobs et al. has just published "Corvids create novel causal interventions after all" in Proceedings of the Royal Society B. The paper is a comment on Taylor et al. who recently investigated whether New Caledonian crows make causal interventions in comparison to 2-year-old children, and concluded that New Caledonian crows cannot make causal interventions, whereas most children can. Taylor et al. also question previous work that claim the existence of causal interventions in corvids.

The new paper is a joint comment by researchers from Lund University, Max Planck Institute for Ornithology, University of Oxford and Newcastle University, and is highly critical of Taylor et al.'s conclusions. Both of the study itself and the analysis of previous work on causal intervention in corvids. Jacobs et al. methodically reviews previous studies and conclude that corvids do create novel causal interventions after all.


måndag 13 april 2015


Three raven chicks (around 1 day old)
It seemed as a bit of a shock to all three of us, Rickard, None and me. But there it was, a tiny, pink lump of life - early yesterday morning. By the evening there were two, and this morning three - and still three eggs to go. Beautiful, turquoise eggs, sheltering theese little helpless creatures, that only in a few weeks will have grown almost as big as their parents.

I was a bit worried that the first-time-parents shouldn't get the feeding right - and still it is to early to know. But two of the small chicks have already survived their first night, and it is amazing to witness None gently feed her young. I am grateful that she allows us, so I will not overdo the photographing.


fredag 10 april 2015

Morning chirps!

Early this morning, I went out to feed the ravens and as soon as Juno lifted from the nest I heard it - faint chirps from the nest! It is difficult to judge if there were one or two voices, but the parents seemed very calm and started to bite of small, small pieces och fine meat for their young.
None is still on her nest - the first egg was laid on the 23rd of March - which means that we might expect hatching on the 13th of April. If the first-time-breeders manage to get it right, that is.


onsdag 8 april 2015

The day before the day

Tomorrow it is 21 days since Juno laid her first egg, so at any moment I expect hatching. Today it's a sunny day, and both Juno and None escape the heat (and mayby boredom) for some brief moments in the fresh air.

 Siden, who by now is experienced, stays close to the nest while Juno is having a snack on the ground.

The unexpected nest in one of the experiment rooms gives us a great opportunity to experience everything from a very close distance. Until now, None has been comfortable with us entering the experimentroom and handing over some treats in the compartment next door. But that might change when (and IF) the eggs hatch. Very different from Juno, who fiercely fight for her young, should anybody come too close in her opinion.

Nones partner Rickard enjoys the warm day and has just taken a bath. He seems a bit shocked by the whole business and is difficult to get contact with. But he feeds None in the nest, and chase away intruders as any raven-father-to-be should.