Friday, February 24, 2017

Gyrfalcon

North America's Rarest Falcon Seen in Nova Scotia


Gyrfalcon - Dark Morph - Juvenile  [Jason Dain Photo]
The Gyrfalcon is a very rare winter resident and migrant to Atlantic Canada.  For the last few days there has been one reported from the River Hebert area, near Joggins, NS.  This bird was seen and photographed by several birders on Tuesday, Feb. 21, 2017.  A big 'thank you' goes out to both Jason Dain and Carmella Melanson for the use of their photos.  These are prized images which provide a great educational opportunity for birders, environmentalists, and general nature lovers.

The Gyrfalcon is the world's largest falcon.  It is 51-64 cm long (20-25 in).  For comparison, the Peregrine Falcon is 41-51 cm long (16-20 in).  The Gyrfalcon sits upright often on manmade structures or cliff edges, presumably watching for prey.  It is a super hunter, capable of taking down flying geese or cranes.  Here it would probably be feeding on waterfowl or pigeons.  Its colour is variable.  It occurs in three colour morphs; white, gray and dark; sometimes listed as white, intermediate and dark.  Genders are similar but juveniles are a bit different.  As in most raptors, females are larger.  

The Gyrfalcon is a large, bulky falcon.  It is not as sleek looking as our other falcons (kestrel, merlin, peregrine falcon).  Its wings are wide at the base and pointed.  In flight the tail base looks wide and the tail is longer than that of the peregrine falcon.  When perched the wings extend about 2/3 of the way down the tail length.  In flight its wing beat appears slow but don't be fooled.  This bird is a very fast killing machine.  

The dark morph is dark gray to gray-brown on the back and wings with heavy striping on the breast and underneath.  The gray morph is similar to the dark morph but much lighter overall.  The white morph is all white with dark wing tips and streaks mainly on the upper body parts.  Underneath all morphs show lighter trailing edges of the wings and darker wing coverts.  See photo below.

Gyrfalcon - Dark Morph - Juvenile [Jason Dain Photo]
The adult Gyrfalcon shows yellow on the cere (base of bill), feet and around the eye.  In the juvenile, these features are gray.  

Adult Gyrfalcon [Icelandic Bird Guide, Hilmarsson, JO, p. 106]
The Gyrfalcon has been a famous hawk since medieval times when it was the most desired species for falconry.  Only kings were allowed to use this species.  Unfortunately, falconry is still going on today and these birds are being captured and kept in captivity for this purpose.  

The Gyrfalcon is a holarctic species. In North America it is a year-round resident of Alaska, northern Yukon, Nunavit and Northwest Territories, Ungava, north to our northernmost islands.  It is rare south of these areas, usually coming south in winter.  We have records for New Brunswick for 1989, 1991, 1994, 2000.  I have been lucky enough to have seen 2 gray morphs in Iceland and a white morph here in New Brunswick.

Gyrfalcon [Carmella Melanson Photo]
Gyrfalcon [Carmella Melanson Photo]
Gyrfalcons nest on cliffs or in abandoned raven nests.  Breeding occurs only in the far north.

All the photos shown (except the light gray morph taken from the Icelandic Bird Guide) are of the same bird now present somewhere in Nova Scotia.  It is possible this bird will stay around for a few days yet.  We were unable to locate it yesterday.  We wish it well as it soon journeys to the far north to breed.

Thursday, February 16, 2017

House Sparrow

Old World Species Gets Scarcer

House Sparrow - Male
 The House Sparrow (Passer domesticus) was once a common resident of New Brunswick.  Its numbers have been declining since about 1970.  It was very common in the first half of the 1900s probably because it embraced agricultural communities and city environments in which horses were common.  It is an introduced Eurasian species and was first reported in New Brunswick in 1884.  It all started when eight pairs were released in Brooklyn, New York in 1851.  Several more releases occurred after that, some in the 1870s.  Other groups were captured and released in various places throughout the United States.  One reason this was done was to provide familiar wildlife for local residents who had come from Europe.

House Sparrows are a unique species and have several behavioural traits which set them up for success as an introduced species.  They prefer to live near human habitation.  This provides food and nesting sites and some protection from predators.  They are an active, aggressive species and can successfully compete for food and nesting sites with native species.  They nest before our native species arrive back in the spring so have their preference of nesting sites.  They have 2 or 3 batches per year of up to 5 offspring each.  These traits lead to rapid population increases.

House Sparrow - Female
The House Sparrow is a gray/brown short-legged sparrow.  It represents a different family from our native sparrows.  The male has a black bib, gray crown and brown band from the eye backwards across the neck.  The female is gray/buff with a buffy line over the eye.  In the non-breeding season the male's plumage becomes more brown-buff in colour with a buffy colour infringing on the bib and brown eye line.  Many of us remember the discordant 'cheep cheep' sound these birds make.  They definitely are not musical.

The range of this species covers all of North America and Mexico and extending northward into Labrador and Northwest Territories.  I was surprised recently to see pictures of them thriving in Churchill, MB.  Having Eurasian distribution, they are native to Britain, Scandinavia, Siberia, northern Africa, Arabia, India and Burma.  Because of introductions by humans they have become established worldwide almost everywhere except Antarctica.  Because of this their population is extremely large.  In Europe alone their population is estimated to be 270 million.

House Sparrow - Male, Non-breeding Plumage
House Sparrow - Female, Non-breeding Plumage
Why has our population been declining since 1970?  That is a question pondered by many birders.  This year is the first year we did not find any on the Mactaquac Christmas Bird Count.  Every year since its inception we have found this species around cattle barns.  Very few House Sparrows live in Fredericton now.  The decline is a worldwide phenomenon.  Scientists do not know exactly why this is happening,  It certainly would be multi-factorial.  The huge decrease in the number of farms, removal of horses from the streets, improvement in grain-harvesting efficiency, and use of insecticides would be some of the reasons.  It will be interesting to see what will be the final results of scientific investigations.  As much as many people dislike these spunky little sparrows, it is sad to see them decline so severely.

Thursday, February 9, 2017

Townsend's Solitaire

Rare Western Thrush Visits NB

Townsend's Solitaire
For the past 3 weeks there has been a Townsend's Solitaire (Myadestes townsendi) visiting a feeder area in Riverview.  As shown above, this is a long, slender very gray bird.  It is a member of the Thrush Family (Turdidae) but is a little different from other thrush members that normally live here, e.g., robins, hermit thrushes, bluebirds.  

The Townsend's Solitaire is dark gray above and light gray below.  It has a small dark bill, distinctive white eyering and splashes of beige on its wings.  It has white outer tail feathers and shows a buffy-orange colour under its wings in flight.  It is 21.5 cm long (8.5").  In the photo above note the eyering.  This bird is just beginning to show a bit of beige on the wings.  It is probably a juvenile just getting its adult plumage.

Townsend's Solitaire [National Geographic Complete Birds of North America, p. 483]
The illustration above shows the adult, young and a bird in flight.  Note the buffy/beige patch on the wings of the perched adult and the white outer tail feathers.  The bird in flight shows the distinctive buffy-orange under the wings.  Most young thrushes are spotted as shown above.  Note the long tail.  It would be very unusual to see a young bird here because the bird does not breed in this part of North America.

Townsend's Solitaire
It is rare for this species to show up in NB.  It normally breeds in British Columbia, Yukon and Alaska and winters in the western US south to Mexico.  It is a permanent resident in the mountains of the western US.  Townsend's Solitaires breed in the mountains and come to the lowlands for the winter.  They feed on insects, worms and berries.  Normally they feed on juniper berries in winter.

According to Birds of New Brunswick An Annotated List there have been about 15 records of visits of this species to NB.  They come in fall and winter and often do not come to feeders.  Clearly their arrival is a result of disturbed migration patterns.

Thrushes are noted for their songs.  This species sings a very long warbling sound much like a purple finch or certain warblers.  There is no common species here that one would mistake this species for.  However, it could be mistaken for a Northern Mockingbird which shows up here in small numbers every year now.  The mockingbird is larger and does not have the white eyering, has two white wing-bars and a longer bill.

Winter is an unique time for those interested in birds.  The cold weather and scarcity of food tend to bring birds to feeders.  That makes it easier to notice a rare visitor.  We have had many this year in New Brunswick.



Thursday, February 2, 2017

Pine Grosbeak

Colourful Winter Finches

Pine Grosbeak - Male
A gentle melodic twitter coming from a group of apple trees is a clue to look among the branches and on the ground under the trees for Pine Grosbeaks.  Their full song is a beautiful melodious warble.  

Pine Grosbeaks are a large plump finch (23 cm/9 in) which visits us only in winter, some winters more than others.  This year is a poor finch year so we have only a few Pine Grosbeaks.  They love fruit and berries so would be found in apple and crab trees and in bushes bearing fruit at this time of year.  

The male Pine Grosbeak shows a beautiful pink-to-reddish-pink colour on the head, breast, back and rump.  He is gray on the sides and belly.  His wings are black with two fine white wing bars.  The tail is long, black and notched.  The bill is black, large but stubby.  There is significant regional variation in the intensity of the pink/red colour.

Pine Grosbeak - Female
The female shows a lot of light gray colour with deep yellow to rust on the head, back, and rump.  The wings are gray with two fine white wing bars.  Juveniles resemble the females.

The only species here one would mistake for a Pine Grosbeak is the White-winged Crossbill.  It has similar coloration but is only 2/3 the size and has a very distinctive crossed bill.  Both species feed on spruce cones so partly share the same habitat.

Pine Grosbeak - Male
In the photos above the grosbeaks were feeding on crab apples.  They are a tame species and do not pay humans much attention.  One can get reasonably close for photos.  It is important to give these birds respect and not get so close they are forced to fly away.  They are in these feeding areas because they need food and safety.

Pine Grosbeak - Female [N Poirier Photo]
The photo above shows a different female than the previous one.  Notice the yellow colour is much darker and she is eating high-bush cranberries.  

The Pine Grosbeak is a holarctic species.  It lives in the northern hemisphere around the world.  Here in North America it breeds in the far north.  It winters in the Maritime provinces, the southern parts of the rest of Canada (except British Columbia) and the northern states east of the Rockies.  It is a permanent resident in the area in between these areas.  It prefers coniferous woods as its name implies but feeds on fruit mainly in winter.  

When we have winters with a large population of Pine Grosbeaks present, it is called an 'irruption'.  What makes years when we have many and years when we have few or none?  The abundance or lack of fruit determines its movement in flocks.  That is what drives irruptive years and years of scarcity of this species.  We have lots of fruit this year but they must also be finding plenty further north, hence the low population here so far this winter.  We may have more flocks move in as the winter progresses.