‘CARRION SCAVENGING’: TURKEY VULTURES ON ABACO

January 7, 2019 by Rolling Harbour

‘CARRION SCAVENGING’: TURKEY VULTURES ON ABACO

Turkey Vultures Cathartes aura [TUVUs, to use their Alpha Bird Code for brevity] are a familiar sight flying over Abaco, wheeling effortlessly overhead on thermals or gliding with the wind in singles, pairs, or flocks. Statistically, 83% of all photographs of turkey vultures are taken from below and look like this:

A very good cameraman with a very good camera and very good luck might catch this

Of in-flight shots, 57% are taken in unhelpful light or conditions, and look like the image below (mea maxima culpa). On a positive note, this picture shows the extreme delicacy of the wing-tip feathering (starboard wing, anyway) that enables these birds to adjust their direction and speed with minimal effort.

TUVUs have a wide range in the Americas and the Caribbean, and will prosper in almost any type of habitat. This is mainly because these large birds are almost exclusively carrion feeders, and carrion is everywhere. They spend their days scavenging, or thinking about scavenging, or recalling successful locations to re-scavenge. They do not generally kill live creatures.

The word ‘vulture’ derives from the latin word ‘vulturus‘ meaning ‘ripper’, ‘shredder’, or in more recent times, ‘very loud Metallica song*‘. TUVUs have very good eyesight, and an acute sense of smell that enables them to detect from a considerable distance the scent of decay and consequent release of the chemical ethyl mercaptan. The smell is variously described as ‘persistent penetrating decayed cabbage’ or a ‘pungent malodorous skunk-like odour’. A breeding pair will raise two chicks, which revoltingly are fed by the regurgitation of all the rank and foul… excuse me a moment while I… I feel a little bit… ~~~~~~~~~~~ …alright, fine again now.

When they are not flying, feeding, breeding or nourishing their young, TUVUs like best to perch on a vantage point – a utility post is ideal. But unusually for a bird, you won’t ever hear them sing or call. They lack a SYRINX (the avian equivalent of a larynx), and their vocalisation is confined to grunting or hissing sounds. Here’s a single hiss (at 10 / 15 secs).

These vultures are often seen in a spread-winged stance, which has several functions that include drying the wings, warming the body, and baking bacteria. Possibly it also reduces the miasma of rotting meat that may surround them after a good meal.

Equally happy to spread their wings on a debris-strewn shoreline

10 SCAVENGED TURKEY VULTURE FACTS FOR YOU TO PICK OVER

One local name for a TUVU is ‘John Crow’
An adult has a wingspan of up to 6 feet
Sexes are identical in appearance, although the female is slightly larger
The eye has a single row of eyelashes on the upper lid and two on the lower lid
TUVUs live about 20 years. One named Nero had a confirmed age of 37
LEUCISTIC (pale, often mistakenly called “albino”) variants are sometimes seen

The TUVU is gregarious and roosts in large community groups
The TUVU has few natural predators
Though elegant in flight, they are ungainly on the ground and in take-off
The nostrils are not divided by a septum, but are perforated – from the side one can see through the beak [some humans also suffer from this condition. They tend to ‘sniff’ a lot]

REVOLTING CORNER / DEPT OF ‘WAY TOO MUCH INFORMATION’

SQUEAMISH? THEN LOOK AWAY NOW

UNATTRACTIVE HABITS The Turkey Vulture “often defecates on its own legs, using the evaporation of the water in the feces and/or urine to cool itself, a process known as UROHIDROSIS. This cools the blood vessels in the unfeathered tarsi and feet, and causes white uric acid to streak the legs”. The droppings produced by Turkey Vultures can harm or kill trees and other vegetation. Maybe don’t park your nice car under one of their perching posts…

HORRIBLE DEFENCES The main form of defence is “regurgitating semi-digested meat, a foul-smelling substance which deters most creatures intent on raiding a vulture nest. It will also sting if the predator is close enough to get the vomit in its face or eyes. In some cases, the vulture must rid its crop of a heavy, undigested meal in order to take flight to flee from a potential predator”

DIETARY NOTES TUVUs tend to prefer recently dead creatures, avoiding carcasses that have reached the point of putrefaction. They will occasionally resort to vegetable matter – plants and fruit (you could view this as their side-salad). They rarely, if ever, kill prey – vehicles do this for them, and you’ll often see them on roadsides feeding on roadkill. They also hang around water, feeding on dead fish or fish stranded in shallow water.

ECO-USES If you did not have birds like this, your world would be a great deal smellier and less pleasant place, with higher chance of diseases from polluted water and bacterial spread. TUVUs kept the highways clear and work their way round the town dumps recycling noisome items.

FORAGING TUVUs forage by smell, which is uncommon in birds. They fly low to the ground to pick up the scent of ethyl mercaptan, a gas produced by the beginnings of decay in dead animals. Their olfactory lobe in the brain is particularly large compared to that of other animals.

SEX TIPS Courtship rituals of the Turkey Vulture involve several individuals gathering in a circle, where they perform hopping movements around the perimeter of the circle with wings partially spread. In humans, similar occasions are called ‘Dances’. A pair will fly, with the female closely following the male while they flap & dive… then they land somewhere private and we draw the veil…

My favourite graphic of all time

Credits: Nina Henry (1); Bruce Hallett (2); Keith Salvesen (3, 4, 5, 11); Clare Latimer (4, 6); amy-at-poweredbybirds (7); Wiki, small pics 8, 9); Charlie Skinner (10); Craig Nash (12); Xeno-Canto / Alvaric (sound file); Info, magpie pickings; Birdorable (cartoon); RH (Keep Calm…); depressingnature.com (puking TUVU)

*As Metallica so appropriately wrote and sweatily sang (luckily there’s no verse referencing urination, defecation and puking). ALERT don’t actually play the video – the song hasn’t aged well! In fact… it’s terrible. Woe woe indeed…

The vultures come
See the vultures come for me
Fly around the sun
But now too late for me
Just sit and stare
Wait ’til I hit the ground
Little vultures tear
Little vultures tear at flesh

Warts and all… the gorgeous, hygienic, roadkill-ridding vulture, with a few dirty habits

REDDISH EGRET HUNTING ON THE MARLS, ABACO

February 12, 2018 by Rolling Harbour

REDDISH EGRET HUNTING ON THE MARLS, ABACO

The trouble with reddish egrets is simple: they come in two colourways. There’s the conventional one which is indeed reddish, as one might hope and expect. Then there’s the snow white type (or ‘morph’). That’s the one featured here (with the other dark variety below, for comparison).

Both types are common breeding residents on Abaco. There are theories about which kind outnumbers the other; on balance I’m not sure the difference is very significant. Maybe reddish are a rather more frequently encountered than white, but there doesn’t seem to be much in it.

Looking back at photographs I took last spring, I found a sequence of a hunting white egret. Now these are not exhibition-quality photos. They were taken quite far out on the Marls, and a fair distance from the skiff I was standing on the front (prow?) of.

I had a smallish camera, and a fishing rod tucked under my arm rather hoping not to hear the usually welcome call “Hey RH**, bones at 10 o’clock moving left – 4 of them – give it 30 feet…” So this sequence is designed to give an idea of how the bird hunts the shallows. Rather than standing stock still and suddenly stabbing down to catch a fish, sometimes the egrets will stride purposefully though the shallow water, taking their chances as they move.

A small success at the start of the hunt (look carefully at the tip of the beak) A pause (and a slightly bad hair moment)

I always enjoy watching the actions of these birds make as they go about their work. But now the hunt is over; the egret has worked his way along the shoreline and he’s thinking out his next move…

…which is to fly off and try his luck elsewhere

Your compensation for some mediocre – but hopefully illustrative – shots is a header image from the camera of the highly experienced birdman and photographer Danny Sauvageau.

Finally, the way to tell that you are looking at a reddish egret, whichever version, rather than one of the other available egret / heron candidates is to look at the bill – pinkish, with a black tip. No other egreto-heronish species has this.

A ‘proper’ reddish reddish egret taken in one of the brackish ponds at Crossing Rocks – always a good place to pull in and check for herons and egrets. This one, photographed in March, is in his handsome breeding plumage. Compare the bill with the white morph above – just the same.

** This not in fact how I am customarily addressed. I have a real name. Probably.

Credits: header image, Danny Sauvageau with thanks as always; all mediocre white morphs RH – also the rather better effort comparative photo of a ‘proper’ reddish one; cartoon by the inimitable Birdorable.

WATCHFUL TYRANT: A LOGGERHEAD KINGBIRD ON ABACO

May 22, 2017 by Rolling Harbour

WATCHFUL TYRANT: A LOGGERHEAD KINGBIRD ON ABACO

The Delphi Club on Abaco has a number of permanent residents (or by now – let’s be realistic – maybe their descendants). There’s the huge curly tail lizard that lives under the large stones by the outside staircase. There are the West Indian Woodpeckers that noisily nest in a box under the eaves of the verandah and produce 2 batches of shouty chicks each summer. And there is the silent sentinel – a loggerhead kingbird that spends much of its time in the trees and bushes at the far side of the pool.

It’s a good place to chose. The bird uses the tree branches and shrubs to ‘hawk’ for passing insects, suddenly leaving its perch to pounce, before returning to just the same place to eat its snack – classic flycatcher behaviour. I call it the ‘watchful tyrant’ because the kingbird is nearly always there. Somewhere. If you look carefully and wait patiently. He stays in the shade, so he’s not bright with sunlight (or P/shop) in these photos. This is just the way he is.

Kingbirds are of the family Tyrannidae and the genus Tyrannus. The ‘tyrant’ group includes a number of flycatcher species commonly found on Abaco: the KINGBIRDS (loggerhead and gray), the CUBAN PEWEE and the LA SAGRA’S FLYCATCHER being the most familiar. Note the hook at the end of the beak; and the yellowish tinge to the undertail area.

With the exception of the gray kingbird, the flycatchers named above are very common permanent breeders on Abaco. There’s probably one of them within 20 feet of your house right now. The gray, however, is a summer breeding resident. This is most helpful of it: if you see a kingbird between October and April, it will be a loggerhead. This gives you a 6-month window for near-certain ID.

IT’S SUMMER – SO HOW DO I TELL A LOGGERHEAD FROM A GRAY?

EASY. CLICK HERE

All photos: Keith Salvesen; Cartoon by the legendary Birdorable

SANDWICH TERNS: NO LINK TO BREAD SLICES, SAY SCIENTISTS

August 19, 2016 by Rolling Harbour

SANDWICH TERNS: NO LINK TO BREAD SLICES, SAY SCIENTISTS

Have you noticed how newspapers and periodicals increasingly seize every opportunity for a headline ending “…say Scientists”. It lends a spurious authority to any tenuous assertion, like “astronauts unlikely to find cheese on moon, say Scientists” (suggesting at least the faint possibility of some mature cheddar lodged in a crater). Or “Frooty-pops cereal may protect against ingrown toenails, say Scientists”. To which the proper response is: “research reference please”. But it seems 37.9% of people are actually prepared to believe this tendencious stuff… say Scientists.

But I digress. To the business in hand. The Sandwich Tern (Thalasseus sandvicensis) is a smart-looking medium-sized tern. Its clearest ID signifier among terns is a sharp black beak with a yellow tip. Also, its black legs helpfully distinguish it from other tern species that have orange legs. Sandwich Tern (Sandy Point), Abaco - Bruce Hallett

The origin of the name for this species is an unexpected one. The Thaleasseus (formerly Sterna) simply refers to the sea (Gk). The Sandwich part is more complicated. It’s certainly nothing to do with a tasty filling for a sliced bread snack **. Other bird species such as Branta sandvicensis, an endemic Hawaiian goose, have the name because Hawaii was historically known as the Sandwich Islands. But Sandwich terns are not found there. In fact, the name comes from the town name of Sandwich, Kent UK (sand wic OE – ‘trading post by the sea’). The ornithologist who first described the bird in 1787, John Latham, just happened to live there. (And how fortunate for ornithology that he did not come from Pratts Bottom, also in Kent).

Sandwich Tern, Abaco (Woody Bracey)

Sandwich terns have a wide range around the world. As the range map below show, the most significant breeding area is Great Britain and northern Europe. On Abaco, the birds are uncommon summer residents. Both images above were taken on the main island, the top one at Sandy Point on the jetty (an excellent place for birdwatching, incidentally). Thalasseus_acuflavidus_and_Thalasseus_sandvicensis_map-location-2.svg Sarnie Tern range

Like all the Thalasseus terns, the Sandwich tern plunge-dives for fish. I love the sight of diving terns. They hang high in the air as they scope out the water for fish, only to break free from the sky and smash down into the sea, often emerging with a silver prize. Here’s a wonderful photo of one that missed its meal – and one that succeeded.

Sandwich Tern (Danny Sauvageau) An endearing characteristic of these terns can be seen during their courtship display. The male will catch a fish, then offer it to the female. Her acceptance of the gift signals her readiness to approve the male as a suitable mate.

Of the 12 tern species recorded for Abaco most are summer residents, some of which breed on Abaco. The royals are the only permanent residents; and the Forster’s are the only winter residents. The other 4 species are transient in migration, or vagrant (arctic tern).

Tern Species on Abaco

As I have mentioned before, a very good source for easy ID to distinguish between different birds of the same family is to head off to BIRDORABLE. The drawings (cartoons!) may not be scientific, but they do highlight the most notable distinctions. Invaluable as a last resort. Or first resort, even! For similar-looking birds, compare the beaks and the legs. The composite below shows how simple it is.

91b5e2a19a20fb1eeace596efbac5a57

Noisy neighbours? Put this short recording of a sandwich tern colony in the breeding season on a continous loop, and you have the makings of a powerful retaliatory weapon. They’ll be out within a fortnight…

Alex Lees / Xeno-Canto

** The food we call a sandwich was named after the 4th Earl of Sandwich. He found eating while playing cards inconvenient, so asked his valet for two slices of bread, requesting “and squash a tern between them, if you’d be so very kind…” The Sandwich Islands were also named after his Lordship by Captain James Cook, as a compliment for financially supporting an expedition there, say Historians…

Sandwich_Tern_(Sterna_sandvicensis)_(Ken Billington)

Credits: Danny Sauvageau (1, 4, 5); Bruce Hallet (2); Woody Bracey (3); Ken Billington (6); Alex Lees @ Xeno-Canto, Birdorable, wiki for range map & info, other magpie pickings of glistening facts

INTERNATIONAL VULTURE AWARENESS DAY ON ABACO

September 5, 2015 by Rolling Harbour

INTERNATIONAL VULTURE AWARENESS DAY ON ABACO

Majestic. Soaring. Graceful. Revolting. That’s the Turkey Vulture. It’s quite a while since I posted about them: you can read all about them and their disgusting habits in the post CARRION SCAVENGING. You’ll discover 10 essential facts, their unpleasant little ways with urine and puke, the sound they make, some sex-tips and a Metallica video.

Are you unaware of vultures? Well, today is their day. These dedicated bird days come thick and fast at certain times of year. Tomorrow we celebrate World Shorebirds Day, so I’m giving the vultures their time in the sun today. On Abaco you could hardly fail to be aware of the ubiquitous TVs, and I have chosen a selection of photos, all taken on Abaco, to make a gallery for their day.

Let’s start with some of the more glamourous ‘in-flight’ shots. This is when TVs look their best, as they wheel round floating and swooping on the thermals – singly, in pairs or in flocks.

At closer quarters TVs are till impressive, though arguably less attractive… TVs often use utility wires (header image) or posts to perch on, scope out the territory, or simply to dry their wings

TVs will never be truly adorable. The final image (by Irish photographer Craig Nash) is truly ‘warts and all’… Ah, but look at the sweet little hairs on its head!

Talking of adorable, this is the perfect place for a shout-out for the wonderful BIRDORABLE site. For this special day they have put all their vultures together in one helpful chart. They have a load of fun at Birdorable HQ. You can download birds for children to colour in. Or even get a T-shirt with your favourite bird on it (mine’s a PIPL).

Credits: Craig Nash (1, 7); Nina Henry (2, 3); Bruce Hallett (4); Charlie Skinner (5); Keith Salvesen (6); the incomparable Birdorable

‘CARRION SCAVENGING’: TURKEY VULTURES ON ABACO

July 18, 2013 by Rolling Harbour

‘CARRION SCAVENGING’: TURKEY VULTURES ON ABACO

TURKEY VULTURES (Cathartes aura) are a familiar sight, wheeling effortlessly overhead on thermals or gliding with the wind in singles, pairs or flocks. Statistically, 83% of all photographs of turkey vultures are taken from below and look like this

Of those, 57% are taken in unhelpful light, and look like the one below. On the positive side, this picture show the extreme delicacy of the wing-tip feathering that enables these birds to adjust their direction and speed (this is not the bird above; it was taken by someone else at a different time. But 100% of TV in-flight photos are indistinguishable).

TVs have a wide range in the Americas and the Caribbean, and can prosper in almost any type of habitat. This is probably because these large birds are almost exclusively carrion feeders, and carrion is everywhere. They spend their days scavenging, or thinking about scavenging. They do not kill live creatures.

The word ‘vulture’ derives from the latin word ‘vulturus’ meaning ‘ripper’, ‘shredder’, or ‘very loud Metallica song’. TVs have very good eyesight, and an acute sense of smell that enables them to detect the scent of decay from some distance. A breeding pair will raise two chicks which revoltingly are fed by the regurgitation of all the rank… excuse me a moment while I… I feel a little bit…

When they are not flying, feeding, breeding or feeding young, TVs like best to perch on a vantage point – a utility post is ideal. But unusually for a bird, you won’t ever hear them sing or call. They lack a SYRINX (the avian equivalent of a larynx), and their vocalisation is confined to grunting or hissing sounds. Here’s a hiss (at 10 / 15 secs).

These vultures are often seen in a spread-winged stance, which is believed to serve multiple functions: drying the wings, warming the body, and baking bacteria.

They are equally happy to spread their wings on the ground, the shoreline being ideal

10 SCAVENGED TURKEY VULTURE FACTS FOR YOU TO PICK OVER

One local name for TVs is ‘John Crow’
An adult has a wingspan of up to 6 feet
Sexes are identical in appearance, although the female is slightly larger
The eye has a single row of eyelashes on the upper lid and two on the lower lid
TVs live about 20 years. One named Nero had a confirmed age of 37
LEUCISTIC (pale, often mistakenly called “albino”) variants are sometimes seen
The Turkey Vulture is gregarious and roosts in large community groups
The Turkey Vulture has few natural predators
Though elegant in flight, they are ungainly on the ground and in take-off
The nostrils are not divided by a septum, but are perforated; from the side one can see through the beak [some humans also suffer from MSS (missing septum syndrome). They tend to sniff a lot]

REVOLTING CORNER / TOO MUCH INFORMATION

SQUEAMISH? LOOK AWAY NOW

DIETARY NOTES TVs tend to prefer recently dead creatures, avoiding carcasses that have reached the point of putrefaction. They will occasionally resort to vegetable matter – plants and fruit (you could view this as their salad). They rarely, if ever, kill prey – vehicles do this for them, and you’ll see them on roadsides feeding on roadkill. They also hang around water, feeding on dead fish or fish stranded in shallow water.

ECO-USES If you did not have birds like this, your world would be a smellier and less pleasant place, with higher chance of diseases from polluted water and bacterial spread.

FORAGING TVs forage by smell, which is uncommon in birds. They fly low to the ground to pick up the scent of ethyl mercaptan, a gas produced by the beginnings of decay in dead animals. Their olfactory lobe in the brain is particularly large compared to that of other animals.

SEX TIPS Courtship rituals of the Turkey Vulture involve several individuals gathering in a circle, where they perform hopping movements around the perimeter of the circle with wings partially spread. In humans, similar occasions are called ‘Dances’. In the air, one bird closely follows another while flapping & diving.

For more about Turkey Vultures, including cool videos, visit DEAR KITTY

It’s possible you may enjoy a visit to max-out-cute Birdorable. Click TV below for link