‘ANOTHER GOOD ONE': BRIDLED TERN ON ABACO


Bridled Tern, Abaco Bruce Hallett 2

 ‘ANOTHER GOOD ONE': BRIDLED TERN ON ABACO

Well, with a bit of digging into the naming of this tern species, I have discovered that the ‘bridled’ part of it apparently refers to the white band / collar at the back of its neck. This is puzzling because one would expect a ‘bridle’ to start at the mouth / beak and angle backwards. Like a horse. Like the conspicuous black line from the base of this tern’s beak sweeping back past its eyes and joining its black cap at the back. How wrong that assumption would be…

Far more exciting than the ‘bridle’ question is the origin of the Bridled Tern’s species name, Onychoprion anaethetus. Wondering about the medical-sounding word, I discovered via the excellent ARKIVE that the name derives from the Greek for ‘senseless’ or ‘stupid’, “a reference to the ease with which hungry sailors captured this bird“. So there you have it: not ‘aesthetically pleasing’ or similar compliment, but just plain dozy.

Bridled Tern, Abaco Bruce Hallett 3

The Bridled Tern is a fairly common summer resident on Abaco, where it breeds.  It is one of 12 tern species recorded on Abaco, the others being Sooty Tern, Least Tern, Gull-billed Tern, Caspian Tern, Black Tern, Roseate Tern, Common Tern, Arctic Tern, Forster’s Tern, Royal Tern and Sandwich Tern. 

These terns plunge-dive for fish, but will also take them from the surface. Unlike other terns – for example the Least Tern – they usually dive directly and not from a hover. When courting, the male will rather charmingly woo the female by offering her fish.

Bridled Tern, Abaco Bruce Hallett 1 http://www.xeno-canto.org/sounds/uploaded/XFQFSNTWJY/XC197147-bridled%20tern.mp3 Eveny Louis / Xeno CantoBridled_Tern (Aviceda Wiki)

 Credits: Bruce Hallett (1,2,3), Aviceda (4), Xeno Canto (audio)

OVENBIRDS FOR CHRISTMAS ON ABACO (NB NOT ROAST TURKEY)


Ovenbird.Abaco Bahamas.Tom Sheley.2

OVENBIRDS FOR CHRISTMAS ON ABACO (NB NOT ROAST TURKEY)

The Ovenbird (Seiurus aurocapilla) is a small winter-resident warbler with distinctive orange head feathers that can be raised into a crest.  I’m guessing this accomplishment is mainly used in the breeding season as a way to impress and attract a mate. Maybe when alarmed or excited at other times as well. Right now, with Christmas only ’12 sleeps’ away, they have become a visible presence on Abaco and the Cays despite their shyness and a general tendency to shuffle around in the undergrowth looking for insects and small snails. Ovenbird.Delphi Club.Abaco Bahamas.Tom Sheley.1

You may hardly be aware of these rather unassuming little birds, and as they rootle their way through the dead leaves under shrubs they can look quite dull. See one lit up by the morning sun, however, and you’ll see how pretty and richly marked they are.

Ovenbird, Abaco  Woody Bracey

The Ovenbird enjoys the taxonomic distinction of being the only bird of its genus in the warbler family Parulidae. It is a so-called ‘monotypic’ species. It was formerly lumped in with Waterthrushes, but was found to be genetically dissimilar so its new status was granted. 

Ovenbird.Bahama Palm Shores.Abaco Bahamas.Tom Sheley

The ovenbird is so named because it builds a domed nest (“oven”) with a side-entrance, constructed from foliage and vegetation. They tend to nest on the ground, making them vulnerable to predation. The species name for the ovenbird, Seiurus aurocapilla, has nothing to do with the nest shape, though. It derives from both Greek and Latin, and loosely means ‘shaking tail, golden haired’. No, nothing to do with Miley Cyrus either. Leave it.

Here are some recent shots taken by Charmaine Albury on Man-o-War Cay, showing the orange crest very clearly.

Ovenbird, M-o-W Abaco (Char Albury 3) Ovenbird, M-o-W Abaco (Char Albury 2) Ovenbird, M-o-W Abaco (Char Albury 1)

My plan to include audio of the ovenbird’s song and call has been temporarily thwarted by a glitch, but I’ll add them here when I have overcome the problem.Ovenbird, Abaco (Gerlinde Taurer)

Gauge the size of the bird against the pod it is standing on…Ovenbird, Abaco - Bruce Hallett

In this photo, you can see that the orange crest feathers are raisedOvenbird Seiurus aurocapilla (Cephas, wiki)

Credits: Tom Sheley, Woody Bracey, Charmaine Albury, Bruce Hallett, Gerlinde Taurer, Cephas / Wiki

THICK-BILLED VIREOS: ABACO’S ONLY PERMANENT RESIDENT VIREO


Thick-billed Vireo, Abaco 2 Tom Reed

THICK-BILLED VIREOS: ABACO’S ONLY PERMANENT RESIDENT VIREO

Hard to know why I haven’t got round to featuring these little vireos before. Unlike the other 7 vireo species found on Abaco seasonally or as transients, the Thick-billed Vireo Vireo crassirostris is an ever-present permanent resident of the coppice and scrub; and their unmistakeable repeating song can be heard almost everywhere. It was the first bird song I heard on Abaco, and therefore the TBV was the first bird I learned to ID. I’ve got quite a soft spot for them, really.Thick-billed Vireo, Abaco (Craig Nash)

Although TBVs are very easy to hear and track to a general area of coppice, I find actually seeing the bird creating the noise quite hard – let alone getting a clear camera shot. They always seem to be lurking several feet further away, deeper in the foliage, than the sound suggests. I’ve had some fun making TBV song iPhone recordings along the Delphi drive, practising the technique. If you want to know more about recording and converting to MP3 CLICK HERE.

One of my favourite images, from Gerlinde Taurer: a ‘shouty’ bird. We used it for ‘BIRDS OF ABACO‘.Thick-billed Vireo, Abaco  (Gerlinde Taurer 2)

I also love this perky little guy with a great beady-eyed pose taken by Bruce HallettThick-billed Vireo, Abaco (Bruce Hallett 2)

Here’s a clip of song, which I’m sure will be immediately familiar to Bahamians:

Paul Driver / Xeno Canto

Thick-billed Vireo, Abaco Bahamas.Tom Sheley

The main signifiers for this species, which in combination distinguish the TBV from the other vireo species on Abaco, are:

  • Two white wing bars
  • Yellow patch – usually quite prominent – between eye and beak
  • Thick bill – which immediately rules it out of being one of the 37 warbler species on Abaco…

Text book TBVThick-billed Vireo, Abaco (Becky Marvil 2).jpg

There are marked colour variations in the species according to maturity, season and to an extent gender (though m & f are quite similar). Here’s one that is causing wing-bar confusion by only showing traces. It also has quite dark upper parts.

Thick-billed Vireo, Abaco (Alex Hughes)

This is a very yellow TBVThick-billed Vireo, Abaco (Bruce Hallett 1)Whereas this one has rather anaemic colorationThick-billed Vireo, Abaco Bahamas .Tom SheleyFinally, this pretty TBV is very delicately markedThick-billed Vireo, Abaco (Tony Hepburn)

RELATED POSTS

BLACK-WHISKERED VIREO

PHILADELPHIA VIREO

Credits: Tom Reed (1), Craig Nash (2), Gerlinde Taurer (3), Bruce Hallett (4, 8), Tom Sheley (5, 9), Becky Marvil (6), Alex Hughes (7), Tony Hepburn (10); Paul Driver / Xeno Canto

‘PEEP SHOW': WHITE-RUMPED SANDPIPERS ON ABACO


White-rumped Sandpiper (Woody Bracey)1

‘PEEP SHOW': WHITE-RUMPED SANDPIPERS ON ABACO

The White-rumped Sandpiper Calidris fuscicollis is one of a number of sandpiper species found on Abaco. You can see a gallery HERE. Many of them are confusingly similar, and it is with a sense of relief that one picks out some particular feature on a bird that marks it out from the other species.White-rumped Sandpiper_ACH3425 copy

The white-rumped sandpiper has, for a start, a white patch that shows above the base of the tail, rather in the manner of the yellow-rumped warbler. It is the only sandpiper with such a feature, and it is conclusive of ID… if you actually see it. You’ll notice that in the header image and the one above, no such white patch is visible. So although it is undoubtedly there, the bird you happen to be looking at – perhaps at a distance – may not have arranged its position and feathers to assist you. Frankly, the birds in the WRS group below are not cooperating either, except the furthest (blurry) one.

White-rumped sandpiper (Rick elis.simpson wiki)

You can’t see it on this bird either, as it forages in a pond, spreading concentric circles across the waterWhite-rumped Sandpiper (Woody Bracey)2White-rumped Sandpiper (Woody Bracey)3

Nor with this one. In fact, I have looked at dozens of photos to find a clear shot of said white marking and found only one really good one… but hedged around by the thick thorny protection of copyright.

White-rumped_sandpiper_(2) Rick elis.simpson wiki

However all is not lost. There is another feature of this sandpiper species that is unique to it, at least on Abaco (it is found also in the Baird’s sandpiper, but you won’t see that bird on the island). The unusually long wings of the white-rumped sandpiper extend beyond its tail when it is on the ground. You can see this in the photos above. It is a feature that should be clearly visible as you watch a bird on the shore, even if it isn’t showing its white rump. Here’s a very helpful composite from the Crossley ID Guide (Eastern Birds). You can see the extended wing length in the birds in the foreground. And if you look at the birds in flight, you will see the white rump exposed.

White_Rumped_Sandpiper_From_The_Crossley_ID_Guide_Eastern_Birds

Like all peeps, these birds make high-pitched weebling sounds, which I have seen described as ‘like a child’s squeaky toy’. Here’s a small flock make a characteristic noise.

Ian Cruickshank / Xeno Canto

You will often see a WRS mixed up in a group of other shorebirds, so the wing-length ID method will help pick it out. Also, it will be notably larger than some, for example semipalmated sandpipers. White-rumped Sandpiper + 2 semi-palmated(Woody Bracey)1White-rumped Sandpiper (Woody Bracey)5

NB They are not always found on the shore or in waterWhite-rumped_Sandpiper (Tim Bowman wiki)

Watch white-rumped sandpipers foraging

Credits: Woody Bracey, Tony Hepburn, Rick Elis Simpson, Tim Bowman, Crossley Guides, Xeno Canto

BAHAMA ORIOLE: ABACO’S LOST ENDEMIC SPECIES


Bahama Oriole ABC : D. Belasco

BAHAMA ORIOLE: ABACO’S LOST ENDEMIC SPECIES

FEWER THAN 300 LEFT IN THE WORLD – AND ALL ON ANDROS

Having just posted about the endangered NASSAU GROUPER and its protection by the introduction of a 3-month closed season, it’s time to focus on a rare, beautiful and vulnerable bird, the Bahama Oriole (Icterus northropi). It is IUCN Red Listed as ‘Critically Endangered’. ENDEMIC to the Bahamas, this bird lived only on Abaco and Andros. Not any more. Now you’ll only find them on Andros, the species having been lost to Abaco in very recent memory. The 1990s, in fact. And on Andros, this lovely bird is now struggling against the threat of extinction and is found only in limited areas in very small numbers. The most optimistic population estimate I have found puts the total as fewer than 300 individuals… the consensus puts the likely total in the region of 250.

Bahamas Oriole, Andros (Binkie Van Es)1

Bahamas Oriole, Andros (Binkie Van Es)2

THE SPECIES

In 2010, the Greater Antillean Oriole Icterus dominicensis was separated by the AMERICAN ORNOTHOLOGISTS’ UNION into 4 species, one being the Bahama Oriole. As the BNT wryly put it, “New species are always a source of excitement… but in this case the intrigue is overshadowed by a sense of alarm and urgency”. For by then this new species ‘in its own right’ was limited to certain parts of Andros, in small and diminishing numbers. It had already vanished from some areas – especially in North Andros – were it had formerly been abundant. The best estimates suggested 250 individual birds.

Bahama Oriole - Harold Brewer (via PM) - Version 3

WHEN & WHY DID THEY VANISH FROM ABACO?

This is a classic ‘riddle wrapped in a mystery inside an enigma’. Various sources I have looked at use a formula such as “…became extirpated from Abaco in the 1990s”, or “disappeared for unknown reasons in the 1990s”. I’ve found no clear clue as to the cause – nor even when the last sighting of an oriole on Abaco was made. I haven’t found a photo of one taken on Abaco, although to be fair the option of snapping everything with wings several times using a digital camera with a large chip didn’t exist then. In the next para a number of crucial factors in the more recent decline of the Andros population are given; but as far as I can determine, some at least did not apply in the 1990s, or certainly not to the same extent. Maybe it was a combination of a degree of habitat loss and the gradual decline of a small population that could not breed prolifically enough to sustain the future population **.

Bahama_Oriole (Mxmerce Wiki)

THE MAIN CAUSES OF THE CRITICAL DECLINE ON ANDROS

Lethal Yellowing Disease of the coconut palm, prime nesting habitat for the oriole. In some areas on Andros (e.g. Staniard Creek), the palm has been all but wiped out. 

The arrival and spread of the Shiny Cowbird Molothrus bonariensis, a brood parasite that lays its eggs in the nests of other bird species such as the yellow warbler, the black-whiskered vireo… and the oriole. The cowbird reached Andros in the mid-1990s. The first Abaco report that I have found is from 1999 (so presumably, as the oriole was already gone from the island by then, they were not a factor).  The cowbird is a summer resident on Abaco, though still relatively uncommon; and its range continues to expand northwards. Some might argue that the cowbird should be discouraged from spreading on Abaco right now for the sake of the indigenous warbler and vireo populations – before it is too late.

Habitat loss / island development (although Birdlife International notes “…the planting of coconut palms in residential areas has allowed the species to spread into human settlements”).

Other factors put forward include forestry work, forest fires, diseases, rodents and feral cats – problems that affect many other birds such as the Abaco parrot.

Bahamas Oriole (BNT / Carlton Ward)

The photo below is a pleasure to include in this post. It was taken earlier this year on Andros by Christopher Johnson of Nassau. And here’s the thing. He is 13, and an avid birder. I’m sure he likes his X-Box time, but he certainly knows plenty about birds too. He’s quick off the mark with offering IDs – correct ones – for birds online, and when he saw this bird he knew the significance of it and managed to get some good shots too. This is my favourite, the oriole ‘vocalising’. See below for its song. Here is Christopher’s brief but enthusiastic field report: Awesome trip to Andros this past weekend! Was amazed to see the Bahama Oriole and its nest — feeling great”. Bahama Oriole, Andros (Christopher Johnson) 2

 Paul Driver / Xeno Canto

A GLIMMER OF HOPE?

In the same way that urgent conservation measures were put in place to halt and then reverse the critical decline of the Abaco parrot population, similar projects are in place for the Bahama Oriole on Andros. One proposal is to establish a ‘captive breeding’ program leading to reintroduction and reinforcement of the wild population. According to the American Bird Conservancy, this could even include reintroduction on Abaco… So perhaps in a decade or two, this fine bird will once again become firmly established as one of the birds of Abaco.

Bahamas Oriole, Andros (Binkie Van Es)3

As I said in my Nassau Grouper post, a country’s attitude can to a degree be gauged by the pride with which it features its wildlife and natural resources in its stamps (I used North Korea for adverse comparison). In 2009 The Bahamas Postal Service even issued a ‘Rare Birds’ set featuring the Bahama Oriole.. I rest my case.

Bahama Oriole Stamp birdtheme.org

♦    ♦    ♦    ♦    ♦    ♦    ♦    ♦    ♦    ♦    ♦    ♦    ♦

WHO WAS THE EPONYMOUS MR NORTHROP?

640px-Picture_of_John_Isaiah_Northrop

The comprehensive answer is provided by the University of Glasgow Library Research Annexe in relation to a fine  illustration from A Naturalist in the Bahamas (1910), reprinted in The Auk journal (below) at a time when Icterus northropi was still a mere subspecies:

The yellow and black Bahama Oriole (Icterus Northropi) is a bird species unique to the Bahamas. The bird was named for American ornithologist and zoologist, John Isiah Northrop (1861–91); the illustration comes from an account of the trip Northrop and his botanist wife, Alice, took to the Bahamas in 1889 which was published in his memory: A Naturalist in the Bahamas: John I. Northrop, October 12 1861-June 25, 1891; a memorial volume (New York: Columbia University Press, 1910). It was edited and introduced by Henry Fairfield Osborn, professor of zoology at Columbia University where Northrop worked as a tutor and was killed in a laboratory explosion shortly (9 days) before the birth of his son John Howard Northrop (who became a Nobel prize-winning chemist).

Icterus Northropi illustrated in A Naturalist in the Bahamas (plate 1)

RELATED MATERIAL

“Rediscovering the Bahama Oriole” Erik Gauger, author of the excellent Notes from the Road and photographic contributor to the Birds of Abaco has a good tale of the pursuit of the apparent sighting of a Bahama Oriole on Abaco 2o years after its (supposed?) extirpation. You can read it HERE

The Auk Read more about this journal and the birding history of the Bahamas HERE

There is a Care2Action ‘Save the Bahama Oriole Before It Is Too Late’ petition HERE. It seems to have stalled somewhat, so it would be good to generate some more signatories.

** Mathematically inclined? Find out about the application of the stochastic process to the oriole’s situation. In a nutshell, this concerns the combined effect of several random adverse factors on sustainability, given that the oriole’s already very small population, very limited range and particular habitat requirements militate against breeding expansion, and therefore increase the likelihood of extinction. We can only hope this is not an inevitability…

Image, audio and research credits: American Bird Conservancy, Binkie van Es, BNT / Carlton Ward, Birdlife International, Christopher Johnson, Cornell Neotropical, Harold Brewer, MxMerce, birdtheme.org, Wiki, Xeno Canto / Paul Driver; Uni of Glasgow / Roger Herriott

COMMON YELLOWTHROATS ON ABACO: CHEERFUL WINTER WARBLERS


Common-yellowthroat, Abaco (Erik Gauger)

COMMON YELLOWTHROATS ON ABACO: CHEERFUL WINTER WARBLERS

Abaco is fortunate to be home to the endemic BAHAMA YELLOWTHROAT Geothlypis rostrata, a striking bird with a dashing black mask and bright yellow body in the male. You can see it with its fellow endemics HERE. But there is similar winter resident species, the COMMON YELLOWTHROAT Geothlypis trichas, that can be seen on Abaco between October and March. Now is a very good time to look out for them. However, the two species are easy to confuse.

Common Yellowthroat (male)Common Yellowthroat, Gilpin Pond, Abaco Bahamas (Tom Sheley)

Bahama Yellowthroat (male)Bahama Yellowthroat (M) BH IMG_0675 copy

WHAT’S THE DIFFERENCE?

  • SIZE – the BW is slightly larger and sturdier than the CW
  • BEAK – larger in the BW, and some might say it tends to be decurved
  • COLOUR – the BW is more colourful, with more extensive yellow underparts and mask
  • FEMALES – both species lack the mask and are duller; the female BW has a greyer head
  • HABITAT – both are found in the same areas; the CW prefers denser vegetation near water
  • DEBATEABLE – it seems to me the pale stripe behind the mask is usually less prominent in the BW

Common Yellowthroat male with conspicuous pale head-stripe800px-Common_Yellowthroat_by_Dan_Pancamo

Both yellowthroat species are an endearing mix of shy and inquisitive. These birds are responsive to ‘pishing’, and once lured from cover they may remain nearby on low branches or shrubs watching you with interest as you watch them. Their song – similar in both species – is fairly easily imitated (or at least approximated), which may also bring them into the open – a source of great satisfaction to the amateur birder when it works. Unless it’s just coincidence, of course… The songs of the two species recorded below sound almost indistinguishable (except that the first one is professional and the second notably amateur…).

COMMON YELLOWTHROAT 

Todd Wilson / Xeno Canto

BAHAMA YELLOWTHROAT

RH own recording

Female Common Yellowthroats are unassuming and quite delicate little birds. The first of these two images shows an immature bird, with its front beginning to become yellow. The second is a mature female.Common Yellowthroat (f, imm) Bruce Hallett IMG_9435Common Yellowthroat (f) Bruce Hallett IMG_4057

Two more male Common Yellowthroats to admire…Common Yellowthroat (m) Bruce Hallett IMG_4232  Common Yellow-throat, Abaco (Becky Marvil)

Photo Credits: Erik Gauger (1); Tom Sheley (2); Bruce Hallett (3, 5, 6, 7); Dan Pancamo /Wiki (4); Becky Marvil (8) Audio: Xeno Canto; RH

A NEW BIRD SPECIES FOR ABACO: BROWN THRASHER


 Brown Thrasher, Judy Howle / DigiDiva - WunderPhotos

A NEW BIRD SPECIES FOR ABACO: BROWN THRASHER

The third new bird species this year has been found on Abaco by bird authority Woody Bracey.  After the excitement of 6 BLACK-BELLIED WHISTLING DUCKS in June and a FORK-TAILED FLYCATCHER in October comes the very recent sighting (with photos) of a BROWN THRASHER, hitherto unrecorded for Abaco. It was seen near Treasure Cay, at the site of a derelict restaurant.

The Brown Thrasher (Toxostoma rufum) belongs to the same family that includes mockingbirds and the catbird – Mimidae. Its normal range includes Florida where it is resident,  so there’s only 200 miles of ocean to cross to reach Abaco. Easier still with a stop-over on Grand Bahama. However I’ve checked for other Bahamas sightings, and so far I have found one recorded for Grand Bahama, and one for Eleuthera. So this first sighting on Abaco is possibly only the third for the Bahamas, suggesting that the Thrasher is generally not a great adventurer.  

220px-Brown-Thrasher-rangemap

Here are some images in case you happen to see a strange brown speckled bird…Brown Thrasher (Manjith Kainickara wiki)

ADULT AND JUVENILE
Brown Thrasher Toxostoma rufum, Virginia - cbgrfx123 wiki

And here are Woody’s evidential images of his sighting. They may not be such close shots as the others but they are conclusive for the record.P1070843P1070844

BESIDES ONE BIRD VISITING ABACO, WHAT’S  INTERESTING ABOUT THE THRASHER?

  • They are known to have more than 1000 types of song, one of the largest bird repertoires
  • They repeat phrases 2 or 3 times before moving on to another (somewhat like Mockingbirds)

Rick Wigh / Xeno Canto

  • They are omnivorous, eating insects, snails, worms etc; and balancing that with fruit, seeds and nuts
  • They are shy birds, but can be very aggressive when defending territory or a nest site
  • They used their slightly decurved beaks to thrash around under leaves and ground debris as they forage – hence the name

YES INDEED, BUT IS THERE ONE REALLY MEMORABLE FACT ABOUT THEM?

  • OK. Their necks are extremely flexible and they have more vertebrae than camels or (get this!) giraffes.
Brown_Thrasher (Ken Thomas wiki)AUDUBON’S DEPICTION OF A ‘FERRUGINOUS THRUSH’, AS IT WAS THEN KNOWNJohn James Audubon - Ferruginous Thrush

Credits: Judi Howle, Manjith Kainickara, Anon (wiki), Woody Bracey, Ken Thomas; Wunderphoto, Wiki, Xeno Canto