April 24, 2017

Spring Banding 2016 Highlights


The 2016 spring banding season had some of the highest capture rates in Presque Isle for Audubon PA but it wasn't just the high totals that impressed us, we also had many significant highlights.

RECAPTURES:

Both of our banding sites in Presque Isle State Park see a high fidelity rate amongst birds that nest there and it is common for us to recapture birds that we banded in previous years. It really is amazing to see Yellow Warblers return year after year and it is not uncommon for many of them to be at least four or five years old upon recpature. This year we even had several that were six years old and two that were at least EIGHT years old! Keep up the good work, friends, as we all love seeing the flashes of yellow around the park each spring.
We also had a few other notable recaps worth mentioning:

One of the early highlights of the season was this male Eastern Towhee originally
banded on 5/7/2010 and recaptured on 4/20/2016, making this bird seven years old! 

This Great-crested Flycatcher was also originally banded in May 2010,
making this bird at least seven years old, if not older.
This Warbling Vireo was banded as a 'Hatch Year' bird in August 2011, presumably
having 
hatched either in or close to Presque Isle State Park. This spring was
also the first time 
that he/she had been recaptured since being banded. 
This Red-eyed Vireo was banded in the fall of 2011, making her at least six years old,
if not older. We recaptured her with the early start of a brood patch so we finally were able to sex  her as otherwise the sexes of this species are indistinguishable by plumage.


Although it is common for us to recapture birds that we have previously banded, especially those that nest in the park, it is actually not that common for us to recapture birds that other stations have previously banded. This year we had the pleasure of recapturing not one, but TWO male Red-winged Blackbirds that were banded at Long Point Bird Observatory, one in 2014 and one in 2012. What makes this even more unique is the fact that in Audubon PA's history of banding at the Park, we have never recaptured one of their birds, nor they one of ours, despite the fact that they are the closest station to us and band quite a large number of birds each year.






NEW BIRDS:


Going out on a net check really is exciting as you never know what you're going to get. This year we caught several species that we hadn't caught in at least three or more years such as: Acadian Flycatcher, Eastern Wood-pewee, Winter Wren, Blue-headed Vireo and Fox Sparrow.


This was also the first time in Audubon PA's history of banding here in the park that we captured a Pine Warbler



and a Northern Rough-winged Swallow (let alone seven!)



Northern Rough-winged Swallows get their name from the rough barb-like hooks on their outermost primary feathers. Scientists still are unsure of what function these barbs serve but for us banders, we are able to use the direction that the barbs curve to sex these otherwise indistinguishable by plumage birds. We banded five females and two males along with one male Barn Swallow on May 15th. 

This is an example of the barbs of a female Northern Rough-winged Swallow
and if you look closely, you can see that they curve slightly upwards.

Golden-crowned Kinglets often move through our area earlier in in the spring and later in the fall than other migrants, ie either before our banding station opens or after it closes . In fact, in Audubon PA's history of banding in the park, we've only banded them one other time and that was in October of 2008 when we caught 35 of them. 

Presque Isle is north of the traditional breeding range for the Worm-eating Warbler so it was very exciting to catch two this past spring, which now doubles the total amount of WEWA that we've ever banded here in the Park. Previously, we had banded one in May 2012 and one in May 2013.



Another exciting highlight of this past spring season was the week that we banded 6 accipiters, two Cooper's Hawks and four Sharp-shinned Hawks! 
The Sharp-shinned Hawk is named for its sharply keeled, featherless lower legs

As with all accipiters, the immature birds are easily noted by the fact that they are mostly brown, with coarse vertical streaks on white underparts and their eyes are yellow. Adults are distinctly slate/blue-gray coloured above, with narrow, horizontal red-orange bars on the breast and their eyes are red.




When it comes to raptors, most banding stations normally catch immature birds so it was exciting for us to capture an adult male Sharp-shinned Hawk (pictured below). Notice the difference in both eye colour as well as in plumage colour from the immature hawk pictured above.





Besides raptors, we also occasionally capture shorebirds in our mist nets. This year we didn't catch any American Woodcock like last season but we did still catch this beautiful Spotted Sandpiper.



By comparing how extensive the spots are on the breast, we can sex the first bird pictured below as a female and the other bird, who was banded in 2015, pictured below her as a male.






Other interesting things that we saw this season:


Feathers:

This Yellow-rumped Warbler who had almost a perfect heart shape in his one tail feather.

This Black-throated Green Warbler, although its flight feathers were in some of the poorest condition that we have observed on a bird this time of year, it is still amazing to think that this feather damage is not recent and it migrated all the way from its wintering grounds with those feathers.
If you look closely you can see a large cluster of feather mite eggs on the wing of this Red-eyed Vireo. We also saw a large number of Gray Catbirds with ectoparasite activity on their body feathers.



Abnormal Plumage: 


In leucistic birds, affected plumage lacks melanin pigment due to the cells responsible for melanin production being absent. This almost always results in all white feathers. Although leucism is inherited, the extent and positioning of the white colouration can vary between adults and their young, and can also skip generations if leucistic genes are recessive. White feathers can also be caused by chromatophore (pigment cell) defects, rather than an absence of melanin-producing cells, which is what we most likely witnessed on this Bay-breasted Warbler pictured below: 





‘Dilution’ is another condition that is often grouped under the category ‘leucism’ although in dilution, melanin cells are present (unlike in leucistic birds) but produce less pigment than normal. Pictured below is an adult male Blackpoll Warbler, that showed signs of dilution as he was lacking the yellow-orange hue that distinguishes the legs of that species as well as the dark black feathers in his crown as well as his back.



One of the best examples of abnormal plumage that we saw this year was the White-breasted Nuthatch pictured below, who we recaptured several times at one of our sites.







Haha and then there was the day that we caught this mole digging near one of our net lanes! As they aren't that often seen above ground, it was quite exciting to look at one in the hand, even if it was only briefly as he/she was quite squirmy.




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