Gull-billed Tern

Hurricane Dorian Brings Ultra-Rare Birds

Gull-billed Tern 

The Gull-billed Tern (Gelohelidon nilotica) is an ultra-rare visitor to New Brunswick.  The recent bird was found at Maces Bay and has remained for a few days.  It is listed as 'accidental' in 'Birds of New Brunswick:  An Annotated List'.  In short, it appears here extremely rarely and only after severe storms.  Our recent avian visitor was blown here by hurricane Dorian.  It was caught in the hurricane and blown way off course and carried by the severe winds northward.  It must have been exhausted when it arrived.  One wonders how long it was suspended in the storm before it could get to land.  

 

The Gull-billed Tern has been seen here before.  The first recorded specimen came from Grand Manan in 1879.  Most other records came from the Grand Manan area but there also have been reports from Red Head Marsh in 1983 and Eel River Bar in 2003.   The normal breeding range of this species is the coastline of eastern and southern US.  In the winter it is found along the coasts of southern Florida, Texas, Mexico and Central America. 

Gull-billed Tern

Terns are members of the Laridae family along with gulls and skimmers.  Terns are generally smaller than gulls and have straight pointed bills and long narrow wings.  Most have a black cap in breeding plumage.  Most terns eat fish but the Gull-billed Tern in unique in that its diet is mainly insects and some prey from the water's surface like crabs.  It never plunges for prey like most terns.  Our visitor was swooping over a small field beside an inlet off the Bay of Fundy feeding heavily on grasshoppers and other insects.  It reminded me of a very large swallow, the way it swooped and turned abruptly as it caught its prey.  

The Gull-billed Tern is very light in colour.  Its plumage is a very light gray.  The wings are light underneath with some graying near the tips.  The legs are black and the black cap on this individual was turning light in the front aspect as it was showing winter plumage.  The outstanding field mark of this species is its stout black bill, hence its name.  The bird is 36cm/14 in. long and it has a wingspan of 90 cm/ 36 in.  Its white tail is notched and it showed this off well as it wheeled and turned near us.  The only other species we would have to differentiate it from is the Forster's Tern which is smaller, slenderer, and has more pointed wings and a deeply forked tail.

Gull-billed Tern

Gull-billed Terns are colonial or solitary breeders.  They often nest on the periphery of the colonies of other species of terns.  They nest on the open ground and the nest is often hidden among the debris on the shore of coastal beaches or saltwater marshes.  One to four yellow or buff eggs spotted with dark brown are laid and both adults incubate the eggs.  

Gull-billed Tern Showing Tail Shape and Long Wings

The population numbers of Gull-billed Terns has declined along the Atlantic coast.  Historically the millinery trade in the 1800s took its toll on this species.  However, this species is in good population numbers globally.  It is also found in Australia, Europe, Asia and Africa.  From our point of view, the sighting of this rare species in New Brunswick is a noteworthy event and made many birders happy to watch it for the first time.

Hooded Warbler

Rare Birds in Grand Manan

Hooded Warbler [Mark Morse Photo]

Late summer and fall usually bring us a few rare bird species.  Those species are often seen along the coast and especially on Grand Manan.  The recent hurricane Dorian has brought some incredibly rare species to Nova Scotia and a few to New Brunswick.  The Hooded Warbler of today's post was seen on Grand Manan in late August (pre-hurricane) and represents one of the species that seem to get off-course in their southerly migrations. 

The Hooded Warbler (Setophaga citrina) is a startlingly beautiful warbler.  The male in spring sports a black hood which covers its throat, crown and nape.  The hood contrasts with the bright yellow face and forehead.  It has an olive-green back and rump and yellow underneath.  The legs are pink and it has white outer-tail feathers which it uses to 'flash' a potential predator.  The breeding-plumaged female is a paler version of the male with variable amounts of the hood.  

The Hooded Warbler prefers shady undergrowth in mature hardwood forests when it is in the north.  The species is unusual in that the two genders prefer different habitats on the wintering grounds.  The males prefer mature forests but the females prefer scrub land. The normal range of this species is the southeastern US in summer and southern Mexico and the West Indies in winter.  It is a super flier, migrating across the Gulf of Mexico to its wintering area.  

Hooded Warblers are late nesters.  That is a good strategy to avoid parasitism by cowbirds.  They build their nest low in a small tree or dense shrubbery.  The nest is made of dead leaves and plant fibres.  Three to five cream-coloured eggs with brown blotches are incubated for 12 days.  Their diet consists of insects and arthropods like most warblers.  

The male Hooded Warbler is so beautiful that it usually brings out exclamations from birders.  In 1907 Frank Chapman, an early renowned ornithologist, wrote about this species, "Its beauty of plumage, charm of voice, and gentleness of demeanour, make it indeed not only a lovely, but a lovable bird."  Its song is a whistle which repeats ta-wee and ends with tee-too.  Hooded Warblers do not breed in NB so we do not get to hear this 'lovable' bird.

Wilson's Phalarope

Wilson's Phalarope - A Late Summer Migrant

Wilson's Phalarope

 Riverview Marsh was rewarded recently (in late summer) by the arrival of several interesting species of shorebirds.  Among them was a Wilson's Phalarope which remained for about a week, feeding heavily to build up energy for its long flight south.  Three of us were there looking at and photographing the Marbled Godwits when very near us swam a phalarope.  It took a close examination of the many photographs I was able to get in order to identify this shorebird.  See this blog for a post on the Marbled Godwits.

Phalaropes are special shorebirds which are often pelagic, are often seen swimming and are sleek and very agile.  They can be confused with other species of shorebirds but after taking a few moments to watch their behaviour, one can identify them as phalaropes.  We have three species of phalaropes; Wilson's, Red-necked, and Red.  See another post on this blog for a description of the Red-necked Phalarope.

Phalaropes are special in that they have partially lobed feet (Wilson's has the least lobed feet) and a very dense plumage.  Presumably these facts make it easy for them to swim.  They feed on the water and often spin in circles to stir up food, the larvae, crustaceans and insects that constitute their diet.  They will also feed on land where they still also walk in circles.  Another interesting fact about this group of species is that they exhibit gender role reversals.  The females are larger and more brightly coloured than the males.  The females court the males in spring and after she lays the eggs, she assumes her duty is finished!  The males incubate the eggs and raise the chicks.  They have two plumages per year, breeding and non-breeding (winter) plumages.  Those that pass through here are often in transition and that can make identification difficult.

Wilson's Phalarope

The Wilson's Phalarope (Phalaropus tricolor) is usually generally lighter in colour than the other two species.  It is the largest of the 3 species ( 24 cm/9.3 in long).  It has a long, thin, black needle-like bill which helps separate it from other shorebird species.  In breeding plumage the female has a large rufous stripe on the face and neck, a light orange breast, white throat, gray and rufous on the back, and a very light gray crown with a white supercilium (line above the eye).  The male in breeding plumage is similar but much duller in colour.  In non-breeding plumage the black legs turn yellowish olive, the upper plumage is light gray, the crown remains light gray and there is a light gray post ocular stripe.  So, you can see that the individuals in transition can be difficult to identify.  We occasionally see individuals in breeding plumage here in the spring and, as in this case, individuals in non-breeding plumage in the fall (or in transition).

Wilson's Phalarope

As you can see in the photo above, this transitional individual is losing the rufous stripe on its face and neck; the orange on the breast is gone, the black eyeline is fading, and the gray on the crown and back of the neck are becoming lighter in colour.  Also note that the legs are yellow which helps distinguish the Wilson's from our other two phalarope species.

Wilson's Phalaropes breed in interior wetlands throughout western North America.  Some breed along the shores of James Bay in northern Ontario.  They winter in South America especially in inland saline lakes in Argentina, Bolivia, Chile and Peru.  Their preferred breeding habitats include grassy borders of shallow lakes, marshes and reservoirs.  They nest on the ground in a scrape lined with grasses.  The usual four buff eggs are incubated about 18-21 days.

Wilson's Phalarope

The Red-necked and Red Phalaropes spend considerable time at sea.  We often see large flocks of phalaropes in Passamaquoddy Bay and the Gulf of Maine in late summer.  The Wilson's is less adapted to pelagic habitats so rarely is seen at sea.  They spend their time on ponds inland and this makes the species vulnerable to habitat degradation and loss.  They have been especially vulnerable on prairie habitats where draining of wetlands and water diversion projects have robbed them of major staging areas during migration.

The Wilson's Phalarope is named after the renowned ornithologist, Alexander Wilson.  It was first described as a species in 1819 by Louis Jean Pierre Vieillot, a French ornithologist.  The term, phalarope, comes from the Greek, phalaris, which means 'coot' and pous, which means 'foot'.  Given that the coot has lobed toes, it follows that the phalarope has an appropriate name.  It is 'neat' how language has evolved.