Saturday 31 March 2018

Borealis Common Eider in Bold Display

The 18 March 2018 I had an opportunity to take many photos of a flock of 1500 Common Eiders feeding at Cape Spear, Newfoundland. Borealis is the common wintering subspecies of Common Eider wintering in Newfoundland. It was only in recent years that I realized borealis was on the rare side in Nova Scotia, New Brunswick and the New England States. The more southern subspecies dresseri makes up the eider populations in these parts. The segregation of these two populations over time has resulted in two recognizable forms.  Dresseri nests in the Gulf of St. Lawrence, Quebec, New Brunswick, Nova Scotia and Maine. Borealis is the Common Eider nesting in the eastern Arctic.  Common Eiders breeding along the coast of Labrador need more careful study. The break, and merging of features is thought to occur mid way along the length of the coast of Labrador. It is possible that Canadian Wildlife Service personal who have banded eiders on nesting islands along the coast of Labrador have insight on the zone of dresseri vs borealis. The reality is we do not really know.

On the Avalon Peninsula, Newfoundland large numbers of borealis over winter.  Up to 1% of the adult drakes can be identified as dresseri. There are others that seem to be in betweeners and may represent birds from the merging zone on the Labrador coast. 

This blog posting is intended to show run of the mill borealis eiders, males and females plus some dresseri.

THE DRAKES - Borealis

Borealis Common Eider drakes are relatively easy to differentiate from dresseri. As you look through these photos note 1) the nearly banana-yellow bill, 2) the short and pointed frontal lobe projections of the bill into the forehead 3) the complete lack of any green wash below the black cap.

THE DRAKES - Dresseri

Classic dresseri stick out like sore thumbs among the borealis. There is a serious business going on in that 'nose'.  The frontal lobe broadens out to a rounded dull green intrusion far up into the forehead. Equally distinct for this subspecies when you look a little closer is the green wash along the bottom border of the black cap. Check with the borealis photos and see this area is always white with them.

THE HENS -  Borealis

The separation of female Common Eiders down to subspecies levels is a new world.  All I know is that borealis come in a range of colours from ashy-gray (<2%) to a rich reddish-brown.  I am unaware of what use if any the shape of the frontal lobes of of females will be.  Photo sharing among those from the  Maritimes and Newfoundland could help smooth out the way to the answer .

Note the gray bill and different head shape and the richness of plumage of the classy adult female King Eider in this picture.

Dive ! ! !

Tuesday 20 March 2018

Carrot Bill at Cape Spear, Newfoundland - V-NIGRUM NAILED !!!

March 18, 2018 was a good day for eider watching at Cape Spear, Avalon Peninsula, Newfoundland. March is  usually the best month for eider numbers on the Avalon as the pack ice covers much their feeding areas on the northeast coast.  After a good morning flight of eiders close by the rocks and trying for flight shots in the heavy snow squalls with poor results, I went back in the afternoon when the snow was supposed to let up.  The eiders were no longer flying but a flock of 120 was feeding by the rocks and the light was getting good as the sun broke out in the western sky. In the mornings we are looking east into the rising sun at Cape Spear. Not good.

I got down on the rocks and manged to get unusually close to the eiders by keeping out of sight. The photo opts were the best. There was one female King and a male dresseri among the standard borealis  but it was the superb opportunity to get excellent photos of our always wary common borealis eider that I was happiest with. Then strings of eiders started arriving from the south and without hesitation joined the flock until there were 1500 eiders. They all started swimming toward my hiding place in the rocks.  The sun had gone out and the snow squalls were starting up again but I was not going to miss this. Amazingly the eiders did not notice my head and camera peering around my rock as they started diving. I was firing off the camera at full tilt not even looking at what eiders might be in the shots. I was wanting as many good examples of borealis  as I could get. There were a few adult drake Kings in this flock also.

Then down the long lens in the flurry of mad snapping I caught the sight of a bright orange bill on a Common Eider. It was the Carrot Bill sign we are always on alert for. It could mean the so called Pacific Eider, also known as v-nigrum, from the western Arctic.  I kept the camera pointed on this bird with the finger down on the hammer just in case this was the real thing. I didn't risk trying to find it in the scope or even binoculars for fear of loosing it in the mass of ducks.  At any moment they were likely to stop feeding and swim off shore like they do to work on crushing the sea urchins in their gizzards to make room for some more.

It looked surprisingly good in the camera being larger than the other eiders and the orange of that bill needed no imagination. Then it started preening. I fired rapidly hoping to get even the slightest angle on the under side of the throat and hopefully capturing the patented black 'V' branded under the chin of v-nigrum. I just finished praying for it to rear up and flap its wings when it did just that. The next 12 shots captured a prominent black 'V burned into the white throat.   Elation! As I looked at my booty on the back of the camera the whole flock did move offshore as predicted. But I had got what I wanted.   V-NIGRUM was NAILED 

This was the third confirmed record of Pacific Eider for Newfoundland. BUT in the last three winters there has been a little wave of highly suspect Pacific Eiders accidentally photographed by people after King Eider shots among big flocks of Common Eider.  It is not the surprise it once was.  The Pacific Eider could be sneaking through the central Arctic more often for now as warmer summers create more open water passages from the Pacific to Atlantic.

Here are the photos.

The very first photo. The look of a freshly peeled carrot stands out in a flock of Newfoundland winter eiders which are 99% borealis race with light yellow to rich yellow bills.

A cropped photo shows some of the patented marks of a v-nigrum. The green wash spreads under the black cap unlike borealis, but similar to dresseri from the Maritimes which were also in this flock of birds.

Depending somewhat on the posture of the bird the forehead bulges and creates and less horizontal edge to the black cap. Compare with the borealis

The v-nigrum is a big bird. The extra long sloping bill helps give this bird a more muscular feel.

There is the patented black 'V' on the under side of the chin. It is near impossible to see this feature unless it does something like this bird is doing. Apparently some v-nigrum  lack this mark and some borealis  can have it.

Here is a borealis  Common Eider showing the virgin white under side to the chin.

The v-nigrum  made no mistake it was going to be counted practically standing on the water to show off the 'V'.


In a little while I hope to have another eider blog posting showing the variations in the borealis  Common Eider, males and females.

Thursday 8 March 2018

Thayerish Gull - A Boring but True Story + Mini Rant

Thayer's Gull was recently demoted from full species status by the American Ornithologist Union. I think this was a mistake. The real Thayer's Gull breeding in the western Arctic is surely a different species than the white wing tipped Iceland Gulls breeding in Greenland. The population of Kumlien's Gull breeding in the middle, perhaps larger than the population of either Thayer's or Iceland Gull, is the problem.  I am in the popular camp that the Kumlien's Gull is a population of hybrid Iceland x Thayer's Gulls. I am not a scientist so I am not bothered by DNA or rules of provable species distinctions.  Thayer's Gull and Iceland Gull just feel like different species to me. The Kumlien's Gulls are T'weeners = hybrids.  I can live with that. Just like people in eastern North America deal with Golden-winged Warbler, Blue-winged Warbler and their hybrid forms named Brewster's and Lawrence's Warblers. Two distinct species and some interesting looking hybrids in between

The problem with identifying a bona fide pure blood Thayer's Gull in Newfoundland is that with literally thousands of hybrid Thayer's X Iceland Gull = Kumlien's Gull around there is going to be every gradation of field marks between the two species including some that might be close to identical to a classic Thayer's Gull or Iceland Gull.  I have some personal experience with bona fide Thayer's Gulls on breeding grounds in Pond Inlet, Baffin Island, and in the NWT, especially Inuvik during spring and fall migration. I always got the same feel from these birds being a little more Herring Gull like in build and demeanor.  To my senses they seem more closely related to Herring Gull than Iceland Gull.

My take on seeing a Thayer's Gull in Newfoundland is that it is near impossible to know even if the wingtip pattern meets the criteria for Thayer's. Typically such birds appear like Kumlien's Gull in shape and may have a less than dark eye. Of course some Thayer's are known have palish eyes.  The arguments become impossible and a waste of time because there is no cut off line where you can say this is definitely Thayer's or just a Kumlien's.  

The bird below would pass all the Thayer's wing tip tests.  It seems small headed and has a only half dark iris.  It has the wingtips of a Thayer's but a body of a Kumlien's to my way of thinking.

These photo below are from 5 March 2018 at Quidi Vidi Lake, St. John's, Newfoundland.

Note purplish-red orbital ring typical of both Thayer's and Iceland but different than the yellow-orange of Herring Gull. The iris is heavily speckled and about average for Kumlien's Gull but paler than most Thayer's Gulls.

The dark subterminal band on P10, continuous dark leading web on P9 and the dark mark on P5 are the most important features when deciding on a Thayer's Gull. Having all three key marks on the same bird plus plenty of dark gray on inner webs of P10 and P9 make this a perfect Thayer's Gull wing tip pattern.

MARCH 24 2006
The gull below was watched by Jared Clarke and I at the St. John's dump on 24 March 2006.  The sheer size and strong build of this bird plus the very dark eye scream out Thayer's Gull according my standards which are not perfected or universally accepted by any means. It fed among the Herring Gulls in the garbage unlike the very few Kumlien's Gulls that entered the landfill back in those days and sat back around the fringe rarely actually going into the main feeding area.  The wingtip pattern just makes it into the legal Thayer's range. There was a small dark mark on P5 that is washed out in this slightly over exposed blurry flight shot.   This is one of just two or three gulls in the St. John's area that I had a good feeling was a pure Thayer's Gull after 35 years of gull watching.