Vancouver Avian Research Centre

.....Research - Conservation - Education
June was Lazuli Bunting month with a total of 13 banded. LAZB are among our favourite birds (although we seem to say that about many species!) and are the iconic birds of Colony Farm Regional Park. This year LAZB have been turning up in unusually high numbers and we have received reports of sightings throughout the lower mainland.

Lapis lazuli is a semiprecious rich azure blue gemstone, whose name came from Middle English via Medieval Latin going back to Arabic and Persian words. Lapis means stone while lazuli is the rich blue color diagnostic of male LAZBs.

Although the fluorescent blue of most adult males extends to the head and crown two of the adult birds banded had an unusually extensive buffy-brown wash to their crowns as can be seen in the photos below. This was particularly interesting given that both birds were adults in at least their third calendar year.

Buntings often have an extensive 1st prebasic molt including all lesser, median and greater coverts, carpal covert, alula, tertials, additional inner secondaries and outer primaries. Members of the Cardinalis family like Grosbeaks and Buntings where males have such contrasting and distinctive plumages are very helpful for learning molt patterns and especially helpful in looking for molt limits in females of the same species.

The wings below show an adult (after-second year ASY) male left and second year (SY) male right.

The wing of the ASY male shows no discernible molt limits, all body and flight feathers having been replaced in the birds definitive adult prebasic molt following the breeding season last year. Note the blue edging to all of the primary coverts and remiges (primaries and secondaries).

Our SY male below right shows distinctive contrasts between 2 generations of feathers; juvenal and first basic and illustrates the eccentric pattern of replaced remiges common in this species.

In its 1st prebasic molt following the breeding season last year this bird replaced lesser, median and greater coverts, the carpal covert, alula, the outermost primaries (pp 2-9; primaries are numbered distally away from the birds body with p9 the outermost) and innermost secondaries (ss 5 & 6) and all 3 tertials (ss 7-9). the retained innermost primary and outermost 4 secondaries bracketed in the photo.

This particular bird also replaced the outer 6 primary coverts - notice the washed out, worn and lightly pigmented appearance of the retained juvenal feathers especially the now very worn and tapered 3 innermost primary coverts (red arrow).

The molt limits we talk about to age NA landbirds in the hand are sometimes quite subtle and difficult to see with the untrained eye but the super-macro photo of the primary coverts of a SY male LAZB below clearly shows the difference between feather generations. In this photo the innermost 6 primary coverts and innermost visible primaries are retained feathers - notice again the lightly pigmented appearance and brownish rachises of the retained feathers versus the glossy black rachises of the replaced feathers.

Contrast the bright, fluorescent blue of the adult male above with the drab greyish brown adult female LAZB below and it's easy to see how they can be misidentified or missed altogether in the field.

This after second year (ASY) female again showing no discernible molt limits having replaced all flight feathers (primaries, secondaries and retrices) in her definitive adult prebasic molt following the breeding season last year. We've talked previously how tail shape can be another helpful clue to ageing birds in the hand. It is important not to use tail shape alone however as it is generally not very reliable because of a) individual variation and b) the possibility of accidental loss and replacement (called adventitious molt). Tail shape is not helpful at all in ageing LAZB as both adults and hatch year birds typically replace retrices.
The same super-macro photography we talked about above allows close up views of even the smallest feathers such as the carpal covert of American Goldfinches (AMGO) which is a key feather in ageing this species.

Ageing AMGO is easier than in many species as there are two ageing shortcuts banders can use. First we look for a buffy tip on the carpal covert. At this time of the year only SY birds have a buffy fringe to the terminal edge of this feather - adults lack this buffy tip to the carpal covert (although they can show a white tip).

The photo below left clearly shows a buffy fringe not only to the carpal covert (red arrow) but also to all 3 alula feathers and under alula coverts which are all retained juvenal feathers.

And in spring/summer AMGO’s are the ONLY birds where we can use the prealternate molt for ageing as only SY birds molt their inner GC’s as part of their prealternate molt which can be seen on the photo below right, the red arrow pointing to the replaced glossy black inner greater coverts.

FIVE species of Empidonax flycatchers in one morning was a great test of our Empid ID skills!

As we said in our May 2011 Blog silent Empidonax flycatchers are the birder's ID nightmare but Empids in the hand although confusing are less of a challenge as we have the opportunity to take biometric measurements and examine wing morphology which usually allows us to make the correct identification.

Four of the five Empids banded (in clockwise order starting top left) below are: Least, Dusky, Pacific-slope and Willow Flycatchers.

Wing morphology refers to the shape of the wing and reflects 3 aspects of the primaries; the lengths (or primary projection) and the occurrence of notches on the inner web and emarginations on the outer web. Wing morphology differs between species and allows banders to (usually!) make the correct identification.

This wing shape affects the primary tip spacing and length of the tips of the primaries in relation to the tips of the tertials. Examples of this can be seen below showing the shorter primary projection of Least Flycatcher (photo below left) to the longer primary projection of Pacific-slope Flycatcher (photo below right).

The primary tip spacing on Pacific-slope Flycatcher shows a long gap between P5 and P6 as can be seen in the photo left. This primary tip spacing differs among all the Empidonax flycatchers allowing for accurate identification of birds in the hand.
Lots more visitors to the station this month which included a field trip for 3rd and 4th year students from the University of the Fraser Valley (UFV) taking an introduction to bird biology course. Despite the drizzly day everyone had a great morning with lots of birds and species diversity.

And visitors from as far away as Washington, Philadelphia, Florida and Hungary made it a truly international month for visitors!

Sandy Tassel and Craig Lee (above) were visitors from Bellingham, WA just south of the border, Craig is Executive Director of the Whatcom Land Trust and former director of the international program at the Audubon Society.

 

 

 

 

 

 

 

Our good friend and BC birding expert Dan Bastaja came back for a visit from Hungary where he now lives accompanied by the Carelse family from Maple Ridge.

 

 

We also had an opportunity to visit Eric Demer's banding station in Nanaimo on Vancouver Island. Eric has been training with us for the past several years and has now set up his own operation in Buttertubs Marsh in association with Vancouver Island University where he is a professor.

Eric's slightly odd pose was due the fact that the remote on his camera only had a 2 second time delay so there were several shots of him not quite making it back in to position in time!

A good variety of wood warblers (well for us in the west anyway!) produced Common Yellowthroat, Wilson's, Orange-crowned, MacGillivray's, Yellow-rumped and this handsome after second year (ASY) male Yellow Warbler, VARC's logo bird!

We discussed the prealternate molt in Yellow Warblers in the July 2011 blog when we said that both first year birds and adults undergo a second molt that occurs prior to the next prebasic molt - called the prealternate molt it occurs in both first year birds and adults during the late winter / early spring. In spring and summer first year birds can show three generations of feathers but adults can also show molt limits!

Such is the case with our adult (after second year ASY) male below (the right wing of the bird above). This bird again replaced all body and flight feather during its definitive adult prebasic molt following the breeding season last year. During its prealternate molt in the late winter / early spring it has again replaced the innermost greater coverts and two innermost tertials; the adult prealternate molt limits illustrated with blue arrows.

Oddly this bird had one shorter primary (p2 illustrated with the black arrow) and although this feather was not in sheath (e.g. not growing) it was also not symmetrical and likely just an anomaly.

And record numbers of MacGillivray's Warblers - this nice after second year (ASY) male with the bright white eye arcs was the subject of our image of the month for June!

Hummingbird monitoring continued with the first hatch year birds showing up in our traps. This hatch year (HY) male Anna's Hummingbird showing the sprinkling of magenta-pink feathers on the crown and gorget was also well advanced in its first prebasic molt replacing flight feathers (photo below right)

We've talked previously about ageing hummingbirds based on the deep grooves or corrugations along the rhamphotheca (the horny covering of the bill) lateral to the culmen and couldn't resist a super-macro photograph showing this in the image below.

Operating our electronic hummingbird trap trippers requires extreme concentration as can be seen from the photo of Kyle above right anxiously awaiting the next hummer in the trap. Fortunately Mike was there to help him maintain his focus!
Another month and another Bird Monitoring and Banding Workshop when we welcomed a full house to the June course with attendees from as far away as California this time! Another great group of people who sacrificed an entire weekend to learn all about molt and ageing in NA landbirds and as always their kind workshop evaluations can be seen by clicking here:

June workshop evaluations

June is also the month for baby birds showing all the characteristics of birds in juvenal plumage like prominent gapes, streaked/spotted plumage, loosely textured feathers and natal plumes showing through the head feathers and giving the appearance of little horns as in the photo below of a hatch year House Finch.

And this precocious newly fledged Black-capped Chickadee!

One of our special species studies this year is on Band-tailed Pigeons (BTPI) as little is known about the demographics of populations because their habits and habitat make it impractical to locate and observe or trap an adequate sample of birds and monitoring information about population status is presently limited to annual estimates of relative abundance through the harvesting of birds primarily in the US. However, in the early 1970s the total population size was approximately at 2.9-7.1 million birds in the Pacific Coast region (estimated primarily from harvest reports) and has shown a consistent decline in the species occurrence.

The single greatest challenge in the monitoring and management of band-tailed pigeon populations is the lack of reliable information on population abundance. Existing surveys for this species provide only trends in abundance and no information about absolute population size.

BTPI occur in large numbers (flocks of 100 individuals or more) in the Park where they feed on the abundant elderberry fruit and the addition of our J-Trap has provided a unique opportunity to study this species.

BTPI can breed year round and molting of primaries also occurs year round and in both age groups making ageing and sexing difficult if  not impossible in some birds.

In adult males (photo below) the crown, neck and head is deep pinkish/purple, the white nape band broad, and the green iridescent patch on the hindneck extensive, extending to the bends of the wing.

On the final weekend of the month we welcomed groups from the Young Naturalists and students from Simon Fraser University making it our busiest month ever for visitors to the station and as always it would not be possible to entertain all of these individual and group visitors without the help of our volunteers who at this time of the year set their alarm clocks at ridiculously early hours to get to the banding station for dawn on their weekends off!
Thanks to Mark Habdas, Kerry Kenwood, Carol Matthews, Jason Jones, Debbie Wheeler, Mike Nutter, Kyle Norris, Louise Routledge, Monica Nugent, Sara Legros, Christine Bishop, Kathy Elwood, Rufus Macintyre, Dev Manky, Cyril Chan, Ivand Pulido, Kirsten Wilcox, Andrew Venning, Kelly Palmer-McCarty, Marguerite Mousseau, Kaye Simard, Lauren Orjala, Shannon LaFontaine, Eric Demers, Eleanor Duifhuis, Kate Gibson, Robin Naidoo and Lois Schwarz for their help with banding this  month.

The Vancouver Avian Research Centre Society is a Registered Canadian Charity (# 82118 2656 RR0001)

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