SuburbanCrows

My 80$ IP-cam for neat crow watching arrived in the mail. It is not as easy to set up as I thought. But I already get a life view. I have to go over some network issues on the command line over the next few days. The target is to motion trigger the cam for video recordings of elegant suburban carrions. But that might take a while. So long..

What behavioural observations motivated your question? Describe your species and what you observed.

My observed species is the carrion crow (corvus corone). It is a territorial crow common in Europe, which lives in small swarms. These crows yield certain advantages from the way humans live. Hence they follow us into our environments. Intelligence of crows is a topic that interests me for quite some time. Although there are many experiments with their tool using relatives (new caledonian crows) I haven't come upon many scientific cognitive experiments on carrion crows so far. Which is not surprising, given they are wild animals. If you spend some time with them though, that still seems odd, because you can observe their cleverness at every footstep. Living among their territories I started to provide them food on my patio, usually twice a day in units of two nuts per provision. Right at the begining I could spot them while they were collecting their goodies. But soon after, once they spoted me, watching them behind the closed curtain of my window, they flew away without collecting the food, waiting on the next fir tree till I left. Sometimes other birds even stole the nuts away under their very own eyes without them interfering. It since has become much harder to observe them while collecting. They seem to go to great lengths and costs to avoid, that anyone observes its them collecting the food. After I spent some time in another room, the food still is taken away though. I often perceive the crowing signaling of one individual sitting in a tree when I was leaving a room. Obvisiously the crows (working in pairs of two) are tracking my position in my house. Sometimes I catch a hint and I run to the window and often see a crow escaping.

What question do you want to answer?

Given that my above observation shows strategic, planning action and sophisticated social foraging behaviour, it is safe to assume that carrion crows have evolved high cognitive abilities. Due to the fact that they have altered their bahviour after registering my presence, it holds that they can relate past events to individuals on a given location and remember that relation from then on.

My question is: Can wild living carrion crows not only relate past events to individuals, but can they also relate past events to a specific color while foraging?

What is your hypothesis? (ie. What do you think is a likely answer to your question?)

My educated guess is that wild carrion crows will associate a specific color with food on a given location, as soon as they have established such a relation over time. This means: If they are provided with three differently colored containers on a feeding-platform, they will start to approach and open the container with a specific color containing the food first, after few days - if the relation of container-color and food is kept stable over a period of time.

How do you propose to study or test your hypothesis? List some of the potential confounds you would need to control for (i.e. What are some other factors that could influence the outcome of your study). My experiment would consist of 6 phases. For each phase three different colors are randomly selected (e.g. 'yellow', 'red', 'green'). One of these colors then is choosen by chance to establish a color-to-food-relation ('red'). Each phase lasts ten days with two daily feedings. Every feeding three containers are presented on a feeding-platform arbitrarily, their colors correspond to the colors of the current phase. These containers must be fully opaque and easy to open for crows. Two containers stay empty, but the one with the color of our color-to-food-association (e.g. 'red') will contain a hazlenut on every feeding during the phase. A control group is used. The measurement of successful associations by crows of color-to-food happens by usage of a motion sensing webcamera, which records every food collection by a crow. This allows also to ensure that it is not only the same crow which collects. A possible confound is odour. Hence the containers used during the experiment must be tested with crows to conceal every odour emission. The second confound are visual hints like dents. Therfore, new containers should be used every feeding-cycle. Rattling sound by the hazlenut is no confound: We measure the first hit container.

Back to our priviledged footballclub. Its artificial turf is an other arena where humans protect their habitat from other humans. Every time the double sealed doors are open lots of icons from the reign of the forbidden will tell the visitors the civil code of good social behaviour. The hedge they build around their royal field is high enough for our little blackies to evade anyone who would undertake to chase them away. Ravens are reliant on protective high structures, whether biological (trees) or cultural. The dry artifical turf obvisiously is a synthetic kingdom for insects, thus the crows make a good use of the sportive activity of our suburbanites for their spring and summer foraging.

Like us, they are omnivores, but their energy household is much more demanding than ours. They need to hold a constant body temperature of 42° Celsius. Thus their faster metobalism requires 10 times more energy than ours per kg* respective body size. With a bodyweight of half a kilogramm they need at least 360 KJ energy a day, which can get a lot higher during winter.* Hence like good competitive athletes they are after proteins and carbohydrates: Meat, nuts, weed. Interestingly, they also store and conceal provisions, especially walnuts for the winter season. This could be one hint why they have developped forecasting intelligence during evolution. Why nuts? Peanuts, hazlenuts and walnuts yield 27 KJ energy per gram, which is even higher than swiss chocolate and sugar (both 12 KJ per gram) or beef (18 KJ per gram). Waltnuts contain 60 percent dry mass grease, which is their most important burning fuel during winter. 4 to 5 walnuts per crow and day* are sufficient to make it over the cold season.

For an arbitrary bystander it might stil appear as if this black coated carrion crows engage in an imaginary party of football, there seems even a coach present.

We can't know much about inner mental states including feelings of others (even less so in very differently structured organisms like animals). What something is like is usually discussed under the fancy term Qualia in philosophy. Scientist can describe the world all day long, but they are always evading the question how something is like or feels. Hence we don't know if there is a mental state like fun for this particular crow or «What Is it Like to Be a Bat?» as Thomas Nagel put it in his famous paper.

What this video from Russia documents though, is a huge degree of adventurous and adaptive (- maybe even inventive) intelligence. Even if the crow is transfering or mimicking a behaviour it has originally seen on humans that still implies functional knowledge of the matter.

Here are two other videos, which illustrate playfull and adventurous behaviour of crows (especially in younger age):

http://youtu.be/YbdNtC4V3IM

I remember that in earlier days some crows used to rip our black household garbage bags open every week. Human wastyness is a welcome food source for suburban carrion crows. - Maybe the shiny black even made the crows curious, by mimicking their shiny skirts or maybe their fourth receptor worked better on black.

In Japans suburban areas a knee-jerk government decision enforced this foraging behaviour. Some governmental workers had the idea to prescribe see-through garbage bags to their citizen. Now the crows could even more easily scan the garbage of their suburbans neighbors and this led to an impressive increase in scattering and mess on Japans streets. Unfortunately, even to some upheal against crows.

One thing to mention is that crows do have excellent vision. They can see approximitely five times better than we do. As other birds they have four receptors. Meaning: They not only catch red, blue, green channels but also see ultraviolet wavelenghts. The Japanese Government sought help by a renowed expert, Neuroscientist Shoei Sugita (aka Professor Crow), who then came up with a special yellow garbage bag as a counter meassure. The yellow color (the hue is still kept a company secret) blocks the yellow receptors of the crows, hence, messing with its eyesight. As a result the crow «cannot see what is inside the bag» - Sugita claims. Our government solved the problem in a more old fashioned way: by impossing a monetary fine for anyone who puts his garbage on the roads the evening before collection. They did as well change the color to blue. But on my request they've told me that this happened just that their workers can spot the garbage better.

After all we learned about carrion crows, this trashbag-dress under sexual selection seems costly for females, but beneficial for males. At least in suburban environments.

July, 2014, Weathercondition: Unsettled. It should be summer. - «Rasen gesperrt» it reads.. Keep off the grass! Not every bird or snapshooter cares about signs. This lonesome carrion crow enjoys foraging on the lawn of the suburban village football team. After the heavy rains we have seen during the last days, that is no wonder: The lawn is always shortly cut and thanks to our tidiness it can easily spot its proteins (aka earthworms, insects) and potentially beneign humans. That is why our awkward fellows are often seen in parks and sports grounds.

I struggle with the small integrated lens of my crappy offspring of a camera obscura. It's quite interesting how the crow behaves though. If I don't move, it's strolling around in an arbitrary fashion, if I move closer, it's slowly evading me at the speed I walk. And if I turn right it bends right, pecking in the ground on it's way. No hurry. But it seems to sens a cautious distance of exactly 20-22 meters. If you break the distance by moving faster, it will take usage of its turbo booster for a few meters.