Monday 24 November 2014

More Meadowlark Mania

You'd think that decently clear photos of a common North American species, and input from 5 of our continents sexiest birders, would settle the case on this months Newfoundland meadowlark. But it hasn't, and I'm writing this post to say that there might never be a convincing case for either species (Eastern vs Western) - but I've learned a lot and that's excuse enough to dump all that information here. Hopefully it'll be of use to someone else trying to work out a meadowlark mystery of their own.

Thanks go to Lisa de Leon, Ken Knowles, John Williams, and Paul Linegar for the great photos!

See previous post here.

----------------------------------------------------

This photo shows why we were originally excited by this meadowlark. Limited white in the rectrices (only the outer 2.5 feathers) would seem to indicate Western Meadowlark based on the current field guides. But from talking to experts this isn't as clear-cut of a feature to distinguish the two species as was originally thought. Definitely points in a westerly direction but doesn't bring us there.


Another photo of the spread tail:


Before I go on, it's important to understand the molt patterns of meadowlarks. They exhibit a complex basic molt strategy. That jargon basically means that adults (after hatch years) have one molt per year where they replace all feathers - this happens in the fall. This is called the pre-basic molt. The only exception is that hatch year/first year meadowlarks have two molts during the autumn - called the pre-basic and pre-formative molts.

What this all means is that our bird is almost certainly in complete winter plumage and will keep these same feathers until next year in early Autumn.


A second feature often mentioned to separate Eastern from Western Meadowlarks is the extent of yellow in the malar area. All fresh Autumn meadowlarks have buffy areas to the malar which eventually wear off revealing white or yellow to the inner-half of these feathers.


Flight shots of the Newfoundland meadowlark seemed to indicate a yellow area to the malar - another indicator of Western Meadowlark. However, this is a difficult feature to objectively evaluate - especially considering that this can, apparently, be quite difficult to see on specimens in the hand let alone from individual photos.


The third feature often mentioned in the field guides is the markings on the flanks: spotting for Western, streaking for Eastern. Apparently, again, this is less than reliable - especially for Autumn birds. And to add to the confusion, some photos of the NL bird show spotting, while others show streaking....


----------------------------------------------------------------

This is where I bring in the comments from others based on our photos. Peter Pyle, Peter Burke, Alvaro Jaramillo, David Sibley, and Kevin Mclaughlin all provided comments. All said they were at least somewhat confident in their identifications. Only problem is that 3 voted for Eastern, and 2 for Western. So let's see what they said.

----------------------------------------------------------------
The Eastern camp
----------------------------------------------------------------


Without relying on relatively easy to see and objective features as those mentioned above (extent of white in tail, yellow in malar, etc) the identification criteria more or less moved into subjective criteria. Both perspectives seemed to apply their own biases to the exact same features to explain their  own identification.


That being said, one of the most insightful comments came from Sibley who commented on the upper tail covert pattern: "Eastern uppertail coverts look mostly black, with a broad solid black central shaft streak and small dark bars projecting out from that. Western uppertail coverts are pale gray-brown with distinct dark bars (no dark longitudinal shaft streak). This is the same pattern difference shown on the central tail feathers, but it seems to be more obvious and more reliable on the coverts. The NL bird looks like an Eastern."
This feature can easily be seen in the following photo:




Other comments that were made by the pro-Easterners:

The bird was deemed "too dark-backed" for WEME, "with a slight warmth to the brown" indicating EAME.

"The back can look paler looking in fresh fall Easterns than in spring birds. By spring this veiling wears off, resulting in brighter colours in spring for breeding, including darker-redder backs" for EAME.

"Reddish tinge to the upper parts" is good for EAME. And "likely a female due to the dull head pattern and relatively reduced amount of white in the tail"...

"Solid stripes to the face indicates EAME". "Dark bars on the central rectrices are wide enough for EAME".

A reddish tinge to the back? A subjective observation IMO


----------------------------------------------------------------
The Western camp
----------------------------------------------------------------

"My impression of the bird is that it shows the overall coloration of a fresh Western and not an Eastern."

"All the photos we see on the internet, especially of Eastern from the East, are dominated by worn spring singing males - very very few fresh plumaged birds in the fall. This fails to show how different the two are in fresh plumage aspect. Easterns are a very richly coloured bird with bright buff (quite golden to orange) edgings and rich chestnut (with reddish tones) internal colour to the mantle feathers. Westerns are distinctly paler in both regards - the edges are duller, as well as the internal colours, making them appear ‘greyer’ and lighter, or not nearly as colourful overall. A couple of the flight shots showing the dorsal side and the perched bird show the colours of a Western to me, not nearly bright and rich enough for a fresh Eastern. Although the tail pattern is problematic, I also see the thin bars of a Western compared to the broader thicker marks that an Eastern shows on the central pair. I would have liked to see the eyestripe a bit thinner than this bird’s but I don’t think its a problem."



"I think that the hybrid possibility is not of much value in this record. To me there is too much consistent with the plumage of Western to me in this bird to evoke the concern."


"Seems short-billed, somewhat supportive of a bird of the year. "


"Don’t seem to exhibit the richer buff/golden edgings nor deeper chestnut internal areas I associate with fresh Easterns. The underparts also seem to lack the brightness I associate with the fresh ventral feathers, including those that veil the yellow. The eye line is consistently thicker than I would like but I don’t think its a game changer."


"I see yellow on that malar, the tail pattern, and the bars on the wings/tail that I can see in some photos do not look to become confluent at the rachis. They stay narrow, and even width throughout the feather, which is a Western feature (at least most Westerns, the ones in the Pacific Northwest are Eastern like in this feature)."


"There is definitely yellow in the malar from what I can see. That will become bolder as the pale feather tips wear through the winter."



----------------------------------------------------------------

So there you have it, if you weren't confused before, you better be now!


It was a learning experience, and many thanks are in order for the many people who provided their insight... especially the 5 mentioned above who took the time to provide their own thorough analysis of the photos. Next time we'll be better prepared!









  


--------------------------------------------------------------------------------------------------

Anyone else sick of looking at meadowlark photos?!


There was a tame Queen Eider at Cape Spear yesterday:
Subject of a future blog post!


Saturday 15 November 2014

Saturday Birding

Spent the morning birding from Cape St. Francis to Quidi Vidi this morning with Sir Ed.

Despite strong winds there were only 3 non-gull seabirds at the cape: Thick-billed Murre, Dovekie, & a getting late Northern Gannet.
Nice sunrise though!

3 eiders today - all of which were close by at the point. 
This male has rounded lobes to the bill - indicating that it's a dresseri/Atlantic Common Eider?
Still need some practice on identifying these sub-species...

A leucistic junco has been hanging out at the cape since late October: 


Later that morning a Great Black-backed Gull caught our attention when it caught a large fish and brought it to the beach. I promptly ran after the bird to get the fish.
An Atlantic Mackerel:

I donated it to this 4th (?) winter Herring Gull: 


At Quidi Vidi we came across the first Common Gull (L. c. canus) of the season:
It had a dark iris, but upon close inspection it appears brown.

The left side of the face had a distinct mark below the eye which may help to identify the individual throughout the winter: 

P10 and P9 still have quite a bit to grow: 
Note the almost complete black band on P5.

The large windows of P10 and P9 are visible from the underside of the wing.
P8 also has a window - albeit a small one - visible in the previous photo.



No day of gulling would be complete in St. John's without seeing the infamous Yellow-legged Gull.
This was my 11th sighting of the bird this year (assuming it's the same one that was here last winter)!
The YLGU was the 11th species of gull I saw between yesterday and today.


Lots of Pine Grosbeaks in the city and other unusual places these last few weeks. Including quite a few that are far away from any notable forest and munching on dogberries in peoples yards.
Similar to Purple Finches, PIGRs don't eat the flesh of dog-berries, but prefer to eat the seeds that are within the berry and wastefully let the fruit fall to the ground once they've extracted the seeds.

Saturday 8 November 2014

Meadowlark Calls

With the realization that calls might need to be recorded to figure out what the Newfoundland Meadowlark is, I thought I should compile all the different types of calls into one spot.


Both meadowlark species have a call, a rattle call, and a flight call. Have fun!

---------------------------------------------------------------------
---------------------------------------------------------------------
---------------------------------------------------------------------

A couple resources here:
http://pjdeye.blogspot.ca/2009/02/blackbird-calls-ii-orioles-and.html
http://pjdeye.blogspot.ca/2010/12/blackbird-flight-calls-ii-orioles-and.html
http://www.xeno-canto.org


The call:
Described as (Sibley Guide):

"sharp, electric dziit or jerZIK" for EAME;

"low, bell-like pluk; blackbird-like but more musical" for WEME.





---------------------------------------------------------------------
---------------------------------------------------------------------
---------------------------------------------------------------------


The rattle call:
Described as:
"hard, mechanical rattle ztttttttt" for EAME
"slow, dull rattle vidididididi" for WEME



---------------------------------------------------------------------
---------------------------------------------------------------------
---------------------------------------------------------------------

The flight call:
Described as:
"thin, rising veeet or rrink" for EAME
"slightly lower than Eastern" for WEME


Friday 7 November 2014

A Meadowlark Appears

About a month ago I came across an abandoned field somewhat close to my house that I had previously been unaware of - my immediate impression was that it might be a good spot for sparrows and meadowlarks. I've since checked it 3-4 times, purposefully criss-crossing the field in hopes I'd flush something up. During my first visit there were sparrows everywhere - but none of them were unexpected species. The next couple visits turned up nothing. This morning I happened to be passing by that same field and had meadowlarks on my mind. Wishful thinking of course. But today was one of those days where a dream came true and within a minute of walking out into the field I saw the distinctive shape of a meadowlark flutter towards the ground with its prominent white outer tail feathers.

Even with that 2-second look I was confident enough to send out the text messages. Less than a minute later I had a few "on my way" replies. I flushed the bird once more (it wasn't visible on the ground) and confirmed my previous 2-second view that it was a meadowlark. Lisa was the first person to arrive, she eventually got great photos of the bird in flight - one would think the photos would make the identification straightforward, but it isn't so easy. Even Pyle acknowledges "that this is one of the most difficult in-hand species identification problems" - this is coming from a guy who has probably held hundreds of them in his hand. Today we're stuck with one bird and distant photos.


Without having heard the bird vocalize I had to go to school... photos started streaming into my inbox a couple hours later and things were looking very interesting. Thankfully Lisa de Leon, Ken Knowles, and John Williams all got excellent photos and have been kind enough to let me post them here to help sort out the ID. See Lisa's post for more photos.

------------------------------------

Jared Clarke and I have been trying to sort out the ID since this morning. We haven't made any conclusive identifications yet - but, I hate to say it, I don't think this bird is identifiable without hearing it - the few useful plumage characteristics that are described in the literature fail to separate this bird into EAME or WEME - instead the features are intermediate between the two species. In the mean time, here's a compilation of the most useful photos and information that we have gathered.


To start, the most reliable way to separate these two species is by their voice. At this time of year the birds will only call - thankfully the calls are quite distinctive. However,  I'm not sure if anyone familiar with the different calls actually heard the bird today.


The Eastern Meadowlark call is described more as a "dziit" versus a "pluk" from the Western Meadowlark. To me the EAME call is more like a fart!





-------------------------------------------------------

Included here are 7 photos of todays bird (thanks again to Lisa, Ken, and John!)

EDIT: In my original post I made a noob mistake by reversing the numbering of the rectrices. It didn't really change what the outcome of the discussion was, but probably confused some people! It should all be fixed now...


One of the main plumage characteristics described to separate WEME from EAME in the fall is the extent of white on the rectrices (tail feathers). Meadowlarks have 12 rectrices - they are numbered from inside to outside:


The next photo shows that R6, R5, and about half of R4 are white, while there is a small white area on R3.



Here is a scan of Pyle's diagram of meadowlark tail patterns. EAMEs range from figures A - C, WEMEs range from B - D. So there is obviously quite a bit of overlap. However, the only really expected sub-species of EAME in our area (S. m. magna) has the least amount of white in the rectrices compared to the other sub-species - figures B-C are the only relevant ones for the expected sub-species of EAME.

 Our bird falls somewhere between C and D - much closer to D in my opinion - because it has a small white area along the shaft of R3, and the outer edge of R4 is dark.




This photos shows the dark outer edge to R4.


Another useful resource for studying the Newfoundland Meadowlark has been this website. A feature they point out is the extent of dark along the centre portions of the middle rectrices. EAMEs have more extensive dark areas that are all connected along the centre, while WEMEs have lighter areas that separate the individual dark bars.

This feature is very hard to pick out from todays photos - and considering the wide variation I would say it's best not to make a judgement on what we're seeing. The next two photos come closest to revealing the central rectrix pattern.





A study by Lanyon et. al in 1996 involved hybridizing Western with Eastern Meadowlarks. The resulting rectrices are shown below with Eastern at the top, Western at the bottom, and the hybrid of the two species in the middle.

Our bird fits best with the hybrid combination... the dreaded hybrid...
This is not meant to say that the Newfoundland bird is a hybrid. But certainly indicates that it isn's a "slam-dunk" Western Meadowlark.

This study can be found here.

An important quote from this study:
"Extensive overlap in all mensural characters and in the amount of white in the rectrices precludes the use of these characters for identifying all but the "extreme" specimens."




Other plumage characteristics often talked about are the malar and flank patterns.

Malar pattern is pretty much useless in the Autumn. For what its worth, the malar area on todays bird is buffy. Not white, not yellow.


Flank streaking on Easterns averages heavier and more merged - again, an unreliable feature from what I've been reading.



From all this, I would say that this bird isn't 100% identifiable based on plumage characteristics. Vocalizations are a hope. That won't happen tomorrow though with 100+ km/h winds!!

FWIW, several out of the province birders with a lot more experience with meadowlarks have unanimously said they "think" that it's a Western Meadowlark.




Thursday 6 November 2014

White-rumped Sandpipers Arranged By Plumage

Juvenile White-rumped Sandpipers start arriving in good numbers in late September in Newfoundland with quite a few still here now (early November), and will probably continue to be seen into December.

What's interesting about these juvenile birds is their huge variation in progression of their moult into 1st winter plumage. When the birds hatch they immediately start growing their juvenile plumage which generally consists of bright reddish/orange upper part and upper wing feathers that are fringed with white. During their southward migration they begin moulting into their first winter plumage. Ultimately, this moult is "complete" - meaning that all feathers are replaced (note that most sandpipers have an "incomplete" moult into first winter plumage, WRSAs are an exception). Although all feathers are replaced eventually, only the body feathers, scapulars, and possible wing coverts are replaced during migration - the flight feathers (primaries, secondaries) are replaced on the wintering grounds.

The replacement of mantle feathers, and scapulars is visible in the field and although it doesn't serve much help in identifying them, it can provide an appreciation of bird moult and is just plain interesting!

This juvenile White-rumped Sandpiper has replaced about 10 mantle feathers, and 2 scapular feathers on both sides. The arrows point to the new feathers which are noticeably duller than the old juvenile feathers. These new feathers are part of the 1st winter plumage. So technically this bird is transitioning from juvenile to 1st winter plumage.

These are the feathers to look for when studying/observing the moult of White-rumped Sandpipers at their stop over sites.

-----------------------------------------------------------------

The following 11 photos are of White-rumped Sandpipers taken at various locations and times this Autumn. I've arranged them, as best I could, from full juvenile plumage to first winter plumage.


1: this bird has replaced no scapular feathers, but has replaced a limited # of mantle feathers.

2: one scapular feather and a number of mantle feathers replaced

3: similar to above

4: two scapular feathers and about 10 mantle feathers replaced

5: at least 4 scapulars and what seems like a majority of mantle feathers replaced


6: ~7 scapulars and 80%+ mantle feathers replaced


7: ~eight scapular feathers and 80%+ mantle feathers replaced

8: similar to above


9: similar to above - a whole row of scapulars appears to be replaced here

10: similar to above, but the arrow points to one of the scapular feathers that borders the mantle feathers. So far in the sequence of photos, this is the first bird to have replaced a feather along that tract/row.

11: the most advanced plumage I have photographed this season - many scapulars replaced including those that border the mantle feathers; no wing coverts have been replaced - they continue to have the white-fringing associated with the juvenile plumage of most shorebirds.



Once these birds reach their full first winter plumage they'll have replaced all their feathers. 
Come the spring, they will begin another moult which generally involves replacing only body feathers, the scapulars, and some wing coverts.