Monday, 3 December 2007
Redpolls!
This post is almost a repitition of what I wrote back in March 2007, and you might just want to (re-) read my former post here.
The winter of 2005/2006 started out in a rather ordinary way here along the German Baltic sea coast. November had passed, fall migration had basically ceased and everybody - well, maybe not the general public but those who truly matter: the birders - was awaiting the influx of the winter birds from Scandinavia.
Around the end of the month though, things took a sudden and unexpected turn: Redpolls!
Well, Redpolls aren't very special around here. The central/western European form cabaret has recently colonized this part of Germany and breeding pairs are now frequently seen in gardens and cemeteries all over the place. Each winter, small flocks of the northern flammea are also regulars, usually numbering in their 20ies or 30ies and even though you won't see them each day you're outside, they are around. The winter of 2005/06 however saw an influx of Common Redpolls the like I have never experienced up here. Redpolls were everywhere and even though most flocks were below 100 birds, some exceeded 300.
Very neat.
Then it happened: neighbouring countries, like Denmark to the North and Poland to the East started to report relatively high numbers of Arctic Redpolls within these flocks of Commons and once reports came in from the Netherlands to the West, it was clear that we, too were being overrun by Arctics. Problem was: no reports yet.
How could that be?
Arctic Redpolls are a very rare species in Germany. As a matter of fact, they are really rare. In most years there won't be a single acceptable record and every second or third winter might lead to one or two birds being reported and approved of by the records committee. And that's even an optimistic guess. So my optimistic guess was that none were reported from here not because the species had decided to avoid Germany of all the European countries but because people were seeing but not recognizing them.
All of a sudden, I was a man on a mission.
I ordered all the identification articles I was able to find out about and spent hours and hours in front of my laptop searching for and studying pictures of all sorts of Redpolls. Finally, I felt I was ready and I took my theoretical knowledge to the test: I went out in search for Redpolls.
Okay, I'll cut it short to get to the main point of my post: in the following three months, I studied a total of well over 1,000 Redpolls and found no less than a minimum of 6 Arctics, which might be a record number of Artics found by a single observer in one winter in Germany. So it was pretty good fun.
Yet again, though, there was a problem: back then I didn't have a camera and my digiscoping equipment was horrible, so I had no definitive proof of my "claims". Surely I had told other birders of the Arctics but very frequently, these observers would look at the same flocks the day following an Arctic observation by me and not find the bird amongst the commons. Yet again, I felt, they were seeing but not recognizing!
So what is the problem with identifying an Arctic Redpoll?
The problem seems to be that it is so bleaking similar to the Northern flammea form of the Common Redpoll that even when you look at an Arctic amongst a flammea flock, you don't have that certain light bulp moment kicking in.
You see, when you check through one Warbling Vireo after another in search for a Philadelphia, you go through all of the subtle characters on each bird and often have these moments were you think that this particular Warbling somehow looks different and might show traits of a Philadelphia. So you struggle, and check again, and don't really know what to think of it. But the moment you actually find a Philadelphia, it is plain obvious, bam, there it is, clearly a different species and no mistaking it!
This is not the case with the Arctic Redpoll. Identifying an Arctic Redpoll completely relies on checking a few key field marks but even when you have established that a particular bird simply must be an Arctic, it still doesn't feel like a different bird species amongst the Commons, it just looks like a subtly different bird of the same species.
Therefore, preparation is everything.
And this is something Sibley knows (again!) as well. He's written a short - and I hope he'll extend it like he did on the "Great White" Heron - post on the key identification criteria here to get North American birders prepared for the Hoaries or rather Arctics headed their way. And it seems we might also have another Redpoll invasion this winter here along the southern Baltic coast...
First up, though, there's a need to clarify the taxonomy we are talking about here.
Currently, the Redpolls are divided into three species (two for the more conservative taxonomists):
1. Arctic or Hoary Redpoll Carduelis hornemanni, with two subspecies: C. h. hornemanni breeding on Greenland and neighbouring parts of Canada and exilipes, breeding from Northern Europe accross Siberia into Northern North America.
2. Common Redpoll Carduelis flammea, with three subspecies: islandica on Iceland, rostrata on Greenland and flammea from Scandinavia all the way East to Northern North America.
3. Lesser Redpoll Carduelis cabaret (sometimes considered a subspecies of Common Redpoll), no subspecies: central and western Europe.
So when North American and European birders are searching Redpoll flocks for Arctic/Hoary Redpolls, they are looking at the same forms, trying to find Carduelis hornemanni exilipes amongst Carduelis flammea flammea. Well, some East Coast birders in North America might encounter the Greenland forms, but I'll just forget about that for now...
So now, finally, the part of this post that might bring profit in the form of knowledge to my readers, links and hints:
A very nice homepage for those who can read Swedish (not so much different from German or English) is here, with some bits already translated into English.
Once you've familiarized yourself with the basic identification criteria (summarized nicely in Sibley's post), I have found it very useful to study the bird images available on the Internet, especially tarsiger.com and birdpix.nl, with the Arctic Redpoll links being here and here and the Common Redpoll pics being here and here.
As Sibley has pointed out, there are a few key criteria, and after reading up on Redpoll identification and studying a couple' hundred pictures, I came to the following set of three field marks that a Redpoll must show in order to be identified as an Arctic by me:
a) largest undertail covert purely or almost purely white
b) white rump
c) narrow or no streaking on breast and flanks (as if drawn with a very sharp pencil)
Using these criteria, I was sure to miss a few Arctics as not all Arctics show a combination of these three criteria, but considering the rarity of the species in Germany and the high number of records I obtained during the winter of 2005/06, I considered a very conservative approach appropriate.
Here, however, are a few tricks and pitfalls I encountered using these criteria.
A general problem:
Redpolls are very active and flighty birds and rarely remain still for more than a couple of minutes before taking to the air again. Searching such an active flock of Redpolls for an Arctic by these subtle characters takes a lot of time and quite frequently I would search a flock of no more than 50 or 60 Redpolls for more than an hour before finding an Arctic.
Furthermore, Redpolls are very active birds, and I can only emphesize that what I wrote back then was not a joke:
"You see, the problem was that one field mark could only be seen from below (undertail coverts) while the other one could only be seen from above: the rump.
Now, Redpolls usually were seen feeding somewhere near the ground in high grass or low in bushes until one of the flock got nervous or maybe bored and decided to cause a bit of a stir, so the whole flock flushed and flew around for a few seconds just to settle down at roughly the same spot again. If this happens every minute you have a very hard time checking all these field marks: 30 seconds to find a potential Arctic, 15 seconds to triple check for the one field mark you are able to look at depending on the bird's relative position to you, 15 seconds to wait and hope the bird would turn around so you could check the other key field mark ... Whoops, sorry, 60 seconds are over and the cards get shuffled again.
30 seconds to find a potential Arctic, 15 seconds to triple check for the one field mark you are able to look at etc."
Arctic Redpolls require patience. Lots of cool-blooded patience.
The white undertail coverts:
The white undertail coverts appear to be the most reliable field mark of the Arctic Redpoll. If your bird shows entirely white undertail coverts, it seems that you can safely call it an Arctic/Hoary. Some Arctics, especially females and immatures, might show a thin dark line on the greatest undertail coverts and if the rest of the bird looks like a "classic" Arctic/Hoary, it is still a safe bet. But a strong, dark, arrow- or drop-shaped mark is almost a dead ringer for Common Redpoll.
However, be sure you are looking at the largest, last undertail covert. A Common Redpoll may show no dark pattern (pure white!) on all but the largest, last undertail covert and that can be misleading! This is something to keep in mind.
White rump
The white rump is not a very strong field character of the Arctic as quite a few pale - mostly male - Common Redpoll can show a rump that's close to white (mostly very pale pinkish or a light grey-brown). If your candidate shows a white rump, it might very well be an Arctic, but you still have a few more steps to take before making a certain identification. However, if your bird does not show a white rump, it very, very likely is not an Arctic, not even an immature or female bird.
Beware though that Redpolls often fluff up part of their feathers above the folded wing (on the sides of their back), and when seen from the side, this will very much "definitely" look like a white rump.
This can be seen on the two images below. The first image shows a likely Arctic (female/immature type). The rump is white and the "back flanks" above the wing are fluffed up, leading to a complete white V-shape on the bird's lower back.
The following image shows the same bird again on the left, with a Common Redpoll to the right. Note that the Common also shows a lot of White on the back but that the rump itself is grey/brown, hence producing a pattern of two white lines along the sides of the back but not a complete white "V"-pattern. And yes, that stick is a bit unfortunate but you can still see what I mean...
Tricky birds!
The finely streaked flanks
Arctics mostly show close to no streaks (males) or very few streaks along the upper breast and flanks and these streaks are mostly very thin and sharply defined, as if drawn with a very pointed pencil.
Beware though that some Commons also show reduced streaks and that the streaks on a Common Redpoll can also be quite sharp and well-defined on the breast. The flanks however should always show a more broad, diffuse pattern of stripes.
As Sibley put it so nicely:
"Good luck"!
And patience, heaps of patience, I may add.
The winter of 2005/2006 started out in a rather ordinary way here along the German Baltic sea coast. November had passed, fall migration had basically ceased and everybody - well, maybe not the general public but those who truly matter: the birders - was awaiting the influx of the winter birds from Scandinavia.
Around the end of the month though, things took a sudden and unexpected turn: Redpolls!
Well, Redpolls aren't very special around here. The central/western European form cabaret has recently colonized this part of Germany and breeding pairs are now frequently seen in gardens and cemeteries all over the place. Each winter, small flocks of the northern flammea are also regulars, usually numbering in their 20ies or 30ies and even though you won't see them each day you're outside, they are around. The winter of 2005/06 however saw an influx of Common Redpolls the like I have never experienced up here. Redpolls were everywhere and even though most flocks were below 100 birds, some exceeded 300.
Very neat.
Then it happened: neighbouring countries, like Denmark to the North and Poland to the East started to report relatively high numbers of Arctic Redpolls within these flocks of Commons and once reports came in from the Netherlands to the West, it was clear that we, too were being overrun by Arctics. Problem was: no reports yet.
How could that be?
Arctic Redpolls are a very rare species in Germany. As a matter of fact, they are really rare. In most years there won't be a single acceptable record and every second or third winter might lead to one or two birds being reported and approved of by the records committee. And that's even an optimistic guess. So my optimistic guess was that none were reported from here not because the species had decided to avoid Germany of all the European countries but because people were seeing but not recognizing them.
All of a sudden, I was a man on a mission.
I ordered all the identification articles I was able to find out about and spent hours and hours in front of my laptop searching for and studying pictures of all sorts of Redpolls. Finally, I felt I was ready and I took my theoretical knowledge to the test: I went out in search for Redpolls.
Okay, I'll cut it short to get to the main point of my post: in the following three months, I studied a total of well over 1,000 Redpolls and found no less than a minimum of 6 Arctics, which might be a record number of Artics found by a single observer in one winter in Germany. So it was pretty good fun.
Yet again, though, there was a problem: back then I didn't have a camera and my digiscoping equipment was horrible, so I had no definitive proof of my "claims". Surely I had told other birders of the Arctics but very frequently, these observers would look at the same flocks the day following an Arctic observation by me and not find the bird amongst the commons. Yet again, I felt, they were seeing but not recognizing!
So what is the problem with identifying an Arctic Redpoll?
The problem seems to be that it is so bleaking similar to the Northern flammea form of the Common Redpoll that even when you look at an Arctic amongst a flammea flock, you don't have that certain light bulp moment kicking in.
You see, when you check through one Warbling Vireo after another in search for a Philadelphia, you go through all of the subtle characters on each bird and often have these moments were you think that this particular Warbling somehow looks different and might show traits of a Philadelphia. So you struggle, and check again, and don't really know what to think of it. But the moment you actually find a Philadelphia, it is plain obvious, bam, there it is, clearly a different species and no mistaking it!
This is not the case with the Arctic Redpoll. Identifying an Arctic Redpoll completely relies on checking a few key field marks but even when you have established that a particular bird simply must be an Arctic, it still doesn't feel like a different bird species amongst the Commons, it just looks like a subtly different bird of the same species.
Therefore, preparation is everything.
And this is something Sibley knows (again!) as well. He's written a short - and I hope he'll extend it like he did on the "Great White" Heron - post on the key identification criteria here to get North American birders prepared for the Hoaries or rather Arctics headed their way. And it seems we might also have another Redpoll invasion this winter here along the southern Baltic coast...
First up, though, there's a need to clarify the taxonomy we are talking about here.
Currently, the Redpolls are divided into three species (two for the more conservative taxonomists):
1. Arctic or Hoary Redpoll Carduelis hornemanni, with two subspecies: C. h. hornemanni breeding on Greenland and neighbouring parts of Canada and exilipes, breeding from Northern Europe accross Siberia into Northern North America.
2. Common Redpoll Carduelis flammea, with three subspecies: islandica on Iceland, rostrata on Greenland and flammea from Scandinavia all the way East to Northern North America.
3. Lesser Redpoll Carduelis cabaret (sometimes considered a subspecies of Common Redpoll), no subspecies: central and western Europe.
So when North American and European birders are searching Redpoll flocks for Arctic/Hoary Redpolls, they are looking at the same forms, trying to find Carduelis hornemanni exilipes amongst Carduelis flammea flammea. Well, some East Coast birders in North America might encounter the Greenland forms, but I'll just forget about that for now...
So now, finally, the part of this post that might bring profit in the form of knowledge to my readers, links and hints:
A very nice homepage for those who can read Swedish (not so much different from German or English) is here, with some bits already translated into English.
Once you've familiarized yourself with the basic identification criteria (summarized nicely in Sibley's post), I have found it very useful to study the bird images available on the Internet, especially tarsiger.com and birdpix.nl, with the Arctic Redpoll links being here and here and the Common Redpoll pics being here and here.
As Sibley has pointed out, there are a few key criteria, and after reading up on Redpoll identification and studying a couple' hundred pictures, I came to the following set of three field marks that a Redpoll must show in order to be identified as an Arctic by me:
a) largest undertail covert purely or almost purely white
b) white rump
c) narrow or no streaking on breast and flanks (as if drawn with a very sharp pencil)
Using these criteria, I was sure to miss a few Arctics as not all Arctics show a combination of these three criteria, but considering the rarity of the species in Germany and the high number of records I obtained during the winter of 2005/06, I considered a very conservative approach appropriate.
Most male Arctic Redpolls are quickly found in a flock of Common Redpolls by their paleness and soft pink breast colouration.
Here, however, are a few tricks and pitfalls I encountered using these criteria.
A general problem:
Redpolls are very active and flighty birds and rarely remain still for more than a couple of minutes before taking to the air again. Searching such an active flock of Redpolls for an Arctic by these subtle characters takes a lot of time and quite frequently I would search a flock of no more than 50 or 60 Redpolls for more than an hour before finding an Arctic.
Furthermore, Redpolls are very active birds, and I can only emphesize that what I wrote back then was not a joke:
"You see, the problem was that one field mark could only be seen from below (undertail coverts) while the other one could only be seen from above: the rump.
Now, Redpolls usually were seen feeding somewhere near the ground in high grass or low in bushes until one of the flock got nervous or maybe bored and decided to cause a bit of a stir, so the whole flock flushed and flew around for a few seconds just to settle down at roughly the same spot again. If this happens every minute you have a very hard time checking all these field marks: 30 seconds to find a potential Arctic, 15 seconds to triple check for the one field mark you are able to look at depending on the bird's relative position to you, 15 seconds to wait and hope the bird would turn around so you could check the other key field mark ... Whoops, sorry, 60 seconds are over and the cards get shuffled again.
30 seconds to find a potential Arctic, 15 seconds to triple check for the one field mark you are able to look at etc."
Arctic Redpolls require patience. Lots of cool-blooded patience.
The white undertail coverts:
The white undertail coverts appear to be the most reliable field mark of the Arctic Redpoll. If your bird shows entirely white undertail coverts, it seems that you can safely call it an Arctic/Hoary. Some Arctics, especially females and immatures, might show a thin dark line on the greatest undertail coverts and if the rest of the bird looks like a "classic" Arctic/Hoary, it is still a safe bet. But a strong, dark, arrow- or drop-shaped mark is almost a dead ringer for Common Redpoll.
However, be sure you are looking at the largest, last undertail covert. A Common Redpoll may show no dark pattern (pure white!) on all but the largest, last undertail covert and that can be misleading! This is something to keep in mind.
On most Common Redpolls, the dark tear-mark on the largest undertail covert is rather obvious and can even be seen on this truly horrible digiscopes image of a male.
White rump
The white rump is not a very strong field character of the Arctic as quite a few pale - mostly male - Common Redpoll can show a rump that's close to white (mostly very pale pinkish or a light grey-brown). If your candidate shows a white rump, it might very well be an Arctic, but you still have a few more steps to take before making a certain identification. However, if your bird does not show a white rump, it very, very likely is not an Arctic, not even an immature or female bird.
Beware though that Redpolls often fluff up part of their feathers above the folded wing (on the sides of their back), and when seen from the side, this will very much "definitely" look like a white rump.
This can be seen on the two images below. The first image shows a likely Arctic (female/immature type). The rump is white and the "back flanks" above the wing are fluffed up, leading to a complete white V-shape on the bird's lower back.
The following image shows the same bird again on the left, with a Common Redpoll to the right. Note that the Common also shows a lot of White on the back but that the rump itself is grey/brown, hence producing a pattern of two white lines along the sides of the back but not a complete white "V"-pattern. And yes, that stick is a bit unfortunate but you can still see what I mean...
Tricky birds!
The finely streaked flanks
Arctics mostly show close to no streaks (males) or very few streaks along the upper breast and flanks and these streaks are mostly very thin and sharply defined, as if drawn with a very pointed pencil.
Beware though that some Commons also show reduced streaks and that the streaks on a Common Redpoll can also be quite sharp and well-defined on the breast. The flanks however should always show a more broad, diffuse pattern of stripes.
As Sibley put it so nicely:
"Good luck"!
And patience, heaps of patience, I may add.
Friday, 23 November 2007
A Liddle Riddle
Today's inspiration courtesy of the weather...
Here are two versions of a picture showing a European Oystercatcher in flight, taken on what was surely not the brightest of days about two weeks ago.
One is the original colour version, one was transformed into a black-and-white image.
Can you tell which is which?
In hopes for better weather over the weekend, especially in New Mexico,
Yours truly
Here are two versions of a picture showing a European Oystercatcher in flight, taken on what was surely not the brightest of days about two weeks ago.
One is the original colour version, one was transformed into a black-and-white image.
Version A:
Version B:
Can you tell which is which?
In hopes for better weather over the weekend, especially in New Mexico,
Yours truly
Another Peregrine, another bird's neck gone
Okay, here's the next chapter of our continuing Saga about the Neck-Eating Peregrine.
It's only one picture and not quite as disgusting as the series I linked to recently, but again:
Warning, not a pretty sight during a meal.
It is so easy to forget this fierce side to the falcon's nature when we see one perched on a fence pole in the light of the setting sun.
Happy Thanksgiving or just happy birding trails to non-US readers!
It's only one picture and not quite as disgusting as the series I linked to recently, but again:
Warning, not a pretty sight during a meal.
It is so easy to forget this fierce side to the falcon's nature when we see one perched on a fence pole in the light of the setting sun.
Happy Thanksgiving or just happy birding trails to non-US readers!
Tuesday, 20 November 2007
Bad Idea, but Nice Birds
The initial idea behind this post was some sort of competition, something like a rumble in the jungle and a beauty pageant, a duel between two species I wanted to use to clarify once and for all which continent had the better birds, Europe or North America.
However, upon choosing the pictures I couldn't help but feel the subjects of my initial idea, the two species involved, were just far too cute for anything competitive. So here I am now, ready and motivated to write a post but deprived of an idea.
Well ...
I suppose I just move on to the pics then.
First up, one of our surely most amazing birds - and by "our" I now mean Europe - the breath-taking Long-tailed Tit.
Even though they breed commonly in this part of Germany - and the species is widespread throughout the continent - we mostly see and notice them in winter when they move around in small yet noisy flocks. The birds seen below are of a North-Eastern race as can be seen by their purely white heads. Other subspecies - and there are plenty of them - show a more stripy head and if science and taxonomy were based upon intuition, I'd say the Long-tailed Tit was ripe for a few splits. Well, for the time being there's only one, but frankly, we don't care too much as long as we get to see them often.
Oh, and in case you were wondering: we're not too sad that Giant Pandas don't occur here naturally...
The North American species I wanted to toss into the ring is none other than the Black-capped Chickadee.
Actually, "the Chick" shares quite a few things with its European relatives, I mean beyond taxonomy: it is simply too common to be noticed and truly appreciated by birders.
Which is a pity, it really is!
It might not have the delicate blue of a Blue Tit or the fine pattern of a Crested Tit but it beats the European Marsh's and Willow's and would surely have been a fierce opponent had I stuck to my initial plan with this post.
Honestly, could you easily decide which one of the two is the cutest, the nicest or most beautiful?
Go on, comment, but provide reasons if you can!
Now, looking at the pictures again, I suppose a simple line of text would have been sufficient:
However, upon choosing the pictures I couldn't help but feel the subjects of my initial idea, the two species involved, were just far too cute for anything competitive. So here I am now, ready and motivated to write a post but deprived of an idea.
Well ...
I suppose I just move on to the pics then.
First up, one of our surely most amazing birds - and by "our" I now mean Europe - the breath-taking Long-tailed Tit.
Even though they breed commonly in this part of Germany - and the species is widespread throughout the continent - we mostly see and notice them in winter when they move around in small yet noisy flocks. The birds seen below are of a North-Eastern race as can be seen by their purely white heads. Other subspecies - and there are plenty of them - show a more stripy head and if science and taxonomy were based upon intuition, I'd say the Long-tailed Tit was ripe for a few splits. Well, for the time being there's only one, but frankly, we don't care too much as long as we get to see them often.
Oh, and in case you were wondering: we're not too sad that Giant Pandas don't occur here naturally...
The North American species I wanted to toss into the ring is none other than the Black-capped Chickadee.
Actually, "the Chick" shares quite a few things with its European relatives, I mean beyond taxonomy: it is simply too common to be noticed and truly appreciated by birders.
Which is a pity, it really is!
It might not have the delicate blue of a Blue Tit or the fine pattern of a Crested Tit but it beats the European Marsh's and Willow's and would surely have been a fierce opponent had I stuck to my initial plan with this post.
Honestly, could you easily decide which one of the two is the cutest, the nicest or most beautiful?
Go on, comment, but provide reasons if you can!
Now, looking at the pictures again, I suppose a simple line of text would have been sufficient:
Beauty is in the eye of the birder
Monday, 19 November 2007
Stunning in a Very Disturbing Way
If you thoroughly enjoyed the Texas Chainsaw Massacre movie and think CSI doesn't show enough "forensic details", you might want to check out this link here.
You probably won't be able to understand the text, but you don't have to, just look at the series of pictures on the right and scroll down.
Be warned however, this is really stunning but in a very, excessively disturbing way.
You might not want to follow the link if you are eating, if you have a weak stomach or if young children or your non-birding spouse are around you.
You probably won't be able to understand the text, but you don't have to, just look at the series of pictures on the right and scroll down.
Be warned however, this is really stunning but in a very, excessively disturbing way.
You might not want to follow the link if you are eating, if you have a weak stomach or if young children or your non-birding spouse are around you.
Wednesday, 14 November 2007
Birds 'n' Apples
The letter 'N' is one of the more peculiar of the alphabet's letters in that it is a very social one. It is used - at least in English - to form a connection between things that are either dear to us or go together well.
Oh sure, you need a few examples or you won't believe me.
No problem.
Okay, we all remember that the slogan "Sex 'n' legal Drugs 'n' Rock & Roll" has shaped the lives of a whole generation and that "Sex in addition to legal drugs when combined with Rock & Roll" would not quite have had the same effect.
Or - to stay in the same basic area - the best band in the world surely owes part of their success to the fact that they combined two things that go together well with an 'n': Iro'n'Maiden!!
Very smart!
Ha, ha, you think these examples are a bit far off reality? Then look closer, you won't even have to go beyond your local bar or rather pub:
We all know that Pi equals 3.14159 and that 't' is a very birdy letter (as seen in Tufted Titmouse, Gray-tailed Tattler etc.) but rarely realize that a combination of the two by the letter 'n' will lead not only to a very enjoyable means to measure volume that shouldn't be sported on a car's license plate...
...but is also connected to one of the most pleasurable ways to enjoy our hobby: Birds'n'Beers.
And what's a beer to a birder is an apple to a bird.
Yes, indeed, birds generally enjoy a good and decent apple once in a while, as I was able to witness during my last days in Michigan's Ann Arbor at the nearby Briarwood Mall National Parkinglot.
This in itself might not be so interesting, but Bell Tower Birding always thrives to provide a perspective upon bird life beyond the obvious, and the way birds approach the eating of an apple is a means to take a closer look at bird evolution.
We start with the Anatidae (the family of ducks, geese and swans) and observe the way a Canada Goose tackes an apple:
A Canada Goose will first push and roll the apple around a bit and it looks as if it was making a smart plan on how to best eat it with such a flat and funny bill...
... but I think it simply has no clue how on earth this thing can be eaten.
So the goose just tries to grab any part of the apple...
...which incidentally happens to be the least edible one and we can even see the steam from the upcoming inner rage escape its nostrils.
Now, however, the goose is given a well-meant clap on the back by natural selection as the anger and frustration about the uselessness of its own bill regarding apples will lead it to take the apple and shake it until the edible part breaks open.
Well, neither a smart nor an elegant way but successful in the end, as was to be expected from such an old and ancient group of birds. After all, had the Anatidae been as stupid as we initially thought, they wouldn't still be around, right?
The Laridae however are a more flexible and adaptive group of birds. It seems they have evolved beyond the clueless state of the Anatidae by approaching an apple with direct aggression. Their bill is adapted to effectively eating an apple as the hook is suited to run it through and pick it up ...
... while the sharp mandibles are brilliant to just tear the fruit apart. Notice that the bird above preferred the apple over a pink barrette, clearly identifying it as a young male.
The remains of the apple then get a little toss, a free flight ...
... and down it goes. This is surely a more effective way to eat an apple, but it is still far from stylish.
An inconvenient truth some gulls find hard to swallow.
If then however we turn to one of the more recent bird groups, the songbirds, we will find the highest adaptation to using apples as food. Not only have they discovered that apples on trees are fresher than those below them, they have also developed the most intelligent method of eating an apple.
This is nicely demonstrated by the House Finch seen below.
"If Pi = 3,14159 and its volume is 4/3 r³ times Pi, how long will this apple last if I place my next bite further to the upper left?"
"Well, not very much longer..."
It is generally thought that the songbirds have adapted best to using apples as food.
In my opinion however, this is a mistake.
I give you one word: Raptors.
Oh, yes, we all think raptors are greatly adapted to hunt down meat and will not readily take to eating any vegetable matter. One example are the Ann Arbor Peregrines, shown well in this nice gallery. Their food has been investigated thoroughly by collecting all avian remains from the bottom of Burton Memorial Tower and the results of this study can be found here.
Oh, you only find birds on that list and no fruit?
You think that proves they don't eat veggies?
Ha, to my eye, this whole approach is tainted by our expectations and the results thus cannot be taken as representative of the species' ecological range. I have - naturally - conducted my own bit of citizen science on these falcons and here is what I found.
Way up on the tower is a majestic Peregrine, the fierce male of the pair.
Way down below are what remains of a good Peregrine snack. Whitewash, a feather of an unlucky Yellow-billed Cuckoo and ...
Oh sure, you need a few examples or you won't believe me.
No problem.
Okay, we all remember that the slogan "Sex 'n' legal Drugs 'n' Rock & Roll" has shaped the lives of a whole generation and that "Sex in addition to legal drugs when combined with Rock & Roll" would not quite have had the same effect.
Or - to stay in the same basic area - the best band in the world surely owes part of their success to the fact that they combined two things that go together well with an 'n': Iro'n'Maiden!!
Very smart!
Ha, ha, you think these examples are a bit far off reality? Then look closer, you won't even have to go beyond your local bar or rather pub:
We all know that Pi equals 3.14159 and that 't' is a very birdy letter (as seen in Tufted Titmouse, Gray-tailed Tattler etc.) but rarely realize that a combination of the two by the letter 'n' will lead not only to a very enjoyable means to measure volume that shouldn't be sported on a car's license plate...
...but is also connected to one of the most pleasurable ways to enjoy our hobby: Birds'n'Beers.
And what's a beer to a birder is an apple to a bird.
Yes, indeed, birds generally enjoy a good and decent apple once in a while, as I was able to witness during my last days in Michigan's Ann Arbor at the nearby Briarwood Mall National Parkinglot.
This in itself might not be so interesting, but Bell Tower Birding always thrives to provide a perspective upon bird life beyond the obvious, and the way birds approach the eating of an apple is a means to take a closer look at bird evolution.
We start with the Anatidae (the family of ducks, geese and swans) and observe the way a Canada Goose tackes an apple:
A Canada Goose will first push and roll the apple around a bit and it looks as if it was making a smart plan on how to best eat it with such a flat and funny bill...
... but I think it simply has no clue how on earth this thing can be eaten.
So the goose just tries to grab any part of the apple...
...which incidentally happens to be the least edible one and we can even see the steam from the upcoming inner rage escape its nostrils.
Now, however, the goose is given a well-meant clap on the back by natural selection as the anger and frustration about the uselessness of its own bill regarding apples will lead it to take the apple and shake it until the edible part breaks open.
Well, neither a smart nor an elegant way but successful in the end, as was to be expected from such an old and ancient group of birds. After all, had the Anatidae been as stupid as we initially thought, they wouldn't still be around, right?
The Laridae however are a more flexible and adaptive group of birds. It seems they have evolved beyond the clueless state of the Anatidae by approaching an apple with direct aggression. Their bill is adapted to effectively eating an apple as the hook is suited to run it through and pick it up ...
... while the sharp mandibles are brilliant to just tear the fruit apart. Notice that the bird above preferred the apple over a pink barrette, clearly identifying it as a young male.
The remains of the apple then get a little toss, a free flight ...
... and down it goes. This is surely a more effective way to eat an apple, but it is still far from stylish.
An inconvenient truth some gulls find hard to swallow.
If then however we turn to one of the more recent bird groups, the songbirds, we will find the highest adaptation to using apples as food. Not only have they discovered that apples on trees are fresher than those below them, they have also developed the most intelligent method of eating an apple.
This is nicely demonstrated by the House Finch seen below.
"If Pi = 3,14159 and its volume is 4/3 r³ times Pi, how long will this apple last if I place my next bite further to the upper left?"
"Well, not very much longer..."It is generally thought that the songbirds have adapted best to using apples as food.
In my opinion however, this is a mistake.
I give you one word: Raptors.
Oh, yes, we all think raptors are greatly adapted to hunt down meat and will not readily take to eating any vegetable matter. One example are the Ann Arbor Peregrines, shown well in this nice gallery. Their food has been investigated thoroughly by collecting all avian remains from the bottom of Burton Memorial Tower and the results of this study can be found here.
Oh, you only find birds on that list and no fruit?
You think that proves they don't eat veggies?
Ha, to my eye, this whole approach is tainted by our expectations and the results thus cannot be taken as representative of the species' ecological range. I have - naturally - conducted my own bit of citizen science on these falcons and here is what I found.
Way up on the tower is a majestic Peregrine, the fierce male of the pair.
Way down below are what remains of a good Peregrine snack. Whitewash, a feather of an unlucky Yellow-billed Cuckoo and ...
... an apple.
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