GULAR SACS: SCRATCHING THE SURFACE OF AN IN-DEPTH VIEW…
A half-way intelligent microbe would make a better job of getting the internet into our home than the current ISP that nominally serves, at some expense, Maison Harbour. So I am restricted to posting 2 fantastic photos of gular pouches as a tempter for things to come when the dimwits in charge of the ‘provision’ of ‘service’ of ‘internix’ locate the act that they need to get together.
Spoiler Alert: ‘Gular Sacs’ has nothing to do with modern jazz. You need to go somewhere else for that…
Photo credits (if they load in the next fortnight or so): Phil Lanoue; Franz Delcroix – with thanks for use permission
It’s often a hard decision whether to include a short piece of video footage in a post. By short, I mean less than a minute. On the one hand, there is usually a good reason for inclusion, even if only aesthetic. On the other, it simply takes up more time for busy people who may prefer to flick through an article and enjoy some nice images along the way. Today, you can have the best of both worlds.
Sanderlings are definitively ‘peeps’, a group name that embraces the smallest and squeakiest sandpiper species. They are the wave chasers, the tiny birds that scuttle along the beach, into the retreating tide for a snack from the sand, and back to the beach again as the waves creep in. Their little legs and feet move in a blur, and many people immediately think of wind-up clockwork toys as they watch the birds in action.
One of the joys of being a sanderling is that rock pools fill and empty diurnally. At some time during daylight, there’s the certainty of a quick dip. I was lying on the beach when I took this short video, so that I didn’t spook the birds. I was equipped with a smallish camera (I drowned it the following day. By mistake I mean) but I kept my distance rather than try to get closer and spoil their joyful bathing.
I caught these little birds at a critical moment. You can tell that the tide is coming in fast. The peeps are becoming edgy, and weighing up the joys of immersion in a pool with the less enjoyable prospect of being washed out of the pool by the next wave. Within a minute or so, they had all flocked down the shoreline for a foraging session.
Waves and incoming tide getting a little too close for comfort on the edge of the pool…
Next to the migratory PIPING PLOVERS that favour Abaco as their winter home, the wave chasers are my favourite shorebirds. My keenness on them killed my camera. I went out into the incoming waves to get shots back at the beach with the sun behind me. Great idea until I lost my balance with, as they say, hilarious consequences. Lesson learnt – never turn your back on waves.
If you are walking your favourite beach on Abaco right now, it’s quite possible you may see – or may already have seen – a very poorly seabird. Or one that is dead, I’m afraid. These are Audubon’s Shearwaters, also known as Dusky Petrels. They are the only permanent resident shearwater species on Abaco. Three others (Cory’s, Great and Sooty) are rare transients; and the last – the Manx – is a very rare off-course vagrant.
Each sad bird is part of a tragic and recurrent phenomenon, a so-called die-off event. As in previous years, a few of the birds that succumb may be Great Shearwaters mixed in with the Audubon’s. I first became aware of this problem in June 2015 and wrote two detailed posts about the situation. This bleak time lasted for about a week, and many reports came in from the mainland and the cays from Green Turtle Cay right down to Crossing Rocks, all duly mapped to get the overall picture.
There was thankfully no such problem in 2016, but in 2017 – also in June – there was another die-back event involving a large number of Audubon’s shearwaters (Puffinus lherminieri) appearing in the tideline and on beaches. Many were already dead. Some are still alive, but in a very poor state. The prospects for recovery for birds that were captured and cared for were not good.
Two years on, and the melancholy cycle is repeating itself. A few days ago, Melissa Maura, an expert in the care and recovery of creatures of all kinds, posted an alert and some sound advice:
A heads-up to all Island folk that it appears to be a summer when exhausted Shearwaters (pelagic seabirds) are washing up on our beaches in Eleuthera and Abaco. I have had two calls in 24 hours. Should you find one, understand that it will be in a severe state of exhaustion and stress and that excessive handling will kill it. Please put in a safe pen on a sandy surface, with shallow pan of fresh water and try locate either fresh fish (important) or squid from a bait shop. This may have to be administered by gently opening the beak and inserting one inch long piece of fish every couple of hours until stable. Ideally they need tube feeding, but very few folk can do this. Please contact me on private message if you find any…
An exhausted Audubon’s Shearwater, now being cared for by Melissa Maura
WHY DOES THIS SHEARWATER DIE-OFF HAPPEN?
This is a periodic phenomenon that looks to be settling into a 2-year cycle in the Northern Bahamas (Eleuthera is also affected). The cause is probably a combination of factors, very likely stemming from prevailing mid-summer climate conditions and/or the effect of climate change. This can lead to a shortage of food far out in the ocean where the birds spend their days. This in turn leads to weakness and exhaustion as the birds try to find food. The birds may then land (or fall) in the sea, to be washed ashore in a very bad state, or dead. In 2017, well-known bird expert Woody Bracey noted a correlation between poor fishing conditions out at sea, and an unusual absence of the frigatebirds that are a sure sign of a healthy fish population.
Shearwater washed up on the beach at Winding Bay a couple of days ago
ARE PLASTICS A CONTRIBUTORY FACTOR?
As we must all accept by now, most if not all these birds will unavoidably have ingested some of our discarded plastic. However, that in itself would not explain the simultaneous deaths of many birds of one type in a specific area, at exactly the same time of year, and for a few days only.
WHAT ELSE CAN BE DONE?
The dead birds will be quickly removed by the turkey vultures. If you do find one, you might want to bury it. The prognosis for sick birds is not that good. They may have been carried a long way from open sea and they will be exhausted and starved. Those that are strong enough may recover naturally; but most will sadly die, being too weak and emaciated to survive. There is no available facility able to deal with a large number of very poorly or dying birds.
The most practical advice I can give is:
(1) move the bird gently into the shade if in the sun
(2) provide clean water in a shallow dish
(3) offer finely chopped fish BUT no bread (it’s very bad for birds)
(4) if this seems to be working, then carry on until the bird is strong enough to fly (this may be quite a commitment)
(5) do not reproach yourself if a bird you try to help dies. Many will be in such bad shape by the time they are washed up that they are unlikely to survive whatever steps you take
(6) remember that this a part – a sad part – of the life-cycle of these birds, and (as with other species), a degree attrition is an inevitable aspect of natural life
I’d be interested to hear any other accounts of this year’s dieback, especially of any recovery stories. By all means do this as a comment, or email me, DM, or FB.
Credits: thanks to those on Abaco who have been reporting this event over the last few days; Dominic Sherony (1); Melissa Maura (2, 5); Keith Kemp (3); Kinlarak / wiki (4); Rhonda Pearce (6); Brian Sullivan / Neotropical Birds / Cornell (7); )Richard Crossley / Crossley Guides for the composite picture
There are twelve (12!) species of tern – ‘swallows of the sea’ – that to a greater or lesser extent may be found on Abaco. Whether they will actually be visible at any given time is less certain, though. For a start, the only resident species is the lovely Royal Tern, available at many locations on Abaco and the cays throughout the year.
ROYAL TERNS Thalasseus maximus PR1
In the slightly less commonly-found category are the summer migrant terns that, by definition, are only in residence for around half the year. Four of these are fairly common in certain areas, and actually breed on Abaco; these include arguably the prettiest of all, the bridled tern. The other two tern species (gull-billed and sandwich) are more rare and as far as I can make out do not breed locally; or perhaps only rarely.
LEAST TERN Sternula antillarum SR B 1
BRIDLED TERN Onychoprion anaethetus SR B 2
ROSEATE TERN Sterna Dougallii SR B 2
SOOTY TERN Onychoprion anaethetus SR B 2
GULL-BILLED TERN Gelochelidon nilotica SR 3
SANDWICH TERN Thalasseus sandvicensis SR 4
There is one rare winter resident migratory tern species. I had to check when the last one was recorded for Abaco. It was of course only in January this year, when ace birder-photographer Sally Chisholm saw one at Treasure Cay and managed to photograph it for posterity.
FORSTER’S TERN Sterna forsteri WR 4
The final four ‘Abaco’ terns are very much the occasional visitors. Three of them pass over the Bahamas on their longer migration, but may make a pit-stop around Abaco to take on fuel. Likelihood of sighting one? Slender but not impossible… The fourth, the Arctic Tern, is a very rare vagrant, a bird well away from its usual home or migration route as the result of storms or faulty satnav or sheer happenstance. Don’t travel to the Bahamas intent on seeing one.
CASPIAN TERN Hydroprogne caspia TR 4
As for the remaining three species, they are the transient black tern and common tern; and the vanishingly rare vagrant Arctic tern (the clue is in the name). No photos of any of these I’m afraid, so here’s a handy checklist instead.
ELECTIVE MUSICAL DIGRESSION
Written by Peter Seeger a few years earlier, Turn x 3 was released in 1965, the title track on the second album from the Byrds. At a rather febrile time in US history (Vietnam, draft riots, black civil rightists v cops and so on), this unusually palliative and thoughtful song with its religious connotations to some extent stood for peace and hope in a time of turmoil.
PS the somewhat laboured title of this post shoehorns in the name of another Byrds album, ‘The Notorious Byrd Brothers’
Photo credits: Keith Salvesen (1, 2, 3, 5, 18); Tony Hepburn (4); Alex Hughes (10, 11); Bruce Hallett (6, 7, 12); Woody Bracey (8, 13, 16); Duncan Wright (9); Dick Daniels (14); Sally Chisholm (15); Keith Kemp (17)
One of the pleasures of watching birds (as opposed toBIRDWATCHING, a more committed-sounding enterprise with its own Wiki entry, that may require equipment, books & mag subs…) is to spend some time observing them enjoying themselves. Perhaps you have a feeder, and like to watch the birds getting stuck into the seeds, carelessly flicking the husks around and throwing their ‘feeder shapes’ on the perches. Maybe you like to see the hummers, beaks deep into the little red plastic flowers on the rim of the sugar-water feeder, tiny bodies motionless and upright, wings a glistening blur of rapid movement in the sun.
It is 5.30 pm. The sun is sinking in the early evening sky. The tide is on the rise at the north end of the Delphi beach where the reef joins the land. There is a small spit of sand that will be covered quite soon, but meanwhile two dozen sanderlings mixed in with assorted ruddy turnstones are doing their idiot feeding thing, rushing around on their tiny legs, stabbing in the sand, and generally behaving like clockwork toys on speed. Meanwhile a handful have found the fun to be had in the swirling tide as it pours round the head of the reef onto the sand spit. Yes, it’s sandpiper bath-time!
Towards mid-tide on the rise, the water begins to creep round the rocks and encroach onto the sandbar. At high tide, it is well under water and fish are back in residence. Small sharks sometimes hang in the waves just behind their breaking point over the shallow sand. And so the tidal process repeats.
For the sanderlings, the best part of the day is when the tide is rising. At ± mid-tide is the time for the shore birds to bathe in the tidal pools that form – and as the water pours in around the end of the rocks, it froths like an overenthusiastic bubblebath. Right then is an excellent time to sit peacefully on the beach and watch the entertainment…
Substantial immersion is not out of the question…
These moments don’t last long. Soon the increasing force and height of the water spoils the fun, and the flock will suddenly take flight and move south a little way along the beach, away from the rocks. There’s the incoming tideline to play with – and more importantly, food to be uncovered with each incoming and retreating wave…
Iam reposting this article in the wake of a recent Bird Club of New Providence bird of prey ID query featuring distant but still helpful photos that enabled the ID as an osprey. As far as I can tell from the visible evidence (the images pixellate when enlarged) this is the ‘local’ Bahamian subspecies that differs in subtle ways from the standard North American version. Both types are found in the northern Bahamas; it would definitely be a great ‘get’ to locate one of each on the same day…
I sometimes feature bird comparatives, not least because there is so much scope for confusion that I have to keep checking for myself. Tyrant flycatchers; a number of superficially similar warbler species (all with yellow bits); those vireos; all those heron-y / egret-y types and their disconcerting morphs (hello, white reddish egret).
And so to the magnificent osprey Pandion haliaetus. This time, the comparison is between two subspecies, broadly the North American P. h. carolinensis and the Caribbean P.h. ridgwayi. There is some overlap in Florida, and some evidence of interbreeding. In the northern Bahamas in particular there is also an overlap, so an osprey seen on Abaco could be either variety. You’ll probably be too excited watching it to care much which type it is, but this article will help you if you do…
The two ospreys shown below were recently photographed at Spanish Wells, Eleuthera by Barbara Crouchley. This is a ‘bingo’ photographic scoop, because each type of bird was found in the same region; now we can check out the differences between the two birds.
The first is a North American bird. Note in particular its distinctive eye mask, and the clearly marked upper breast, more so in the female than the male (which may even be white). The overall impression of the upper-parts is dark brown. They are slightly larger than their cousins in the south.
Osprey P.h. carolinensis
In this Caribbean bird with its trophy fish, the eye-mask is absent, and the facial / nape markings are less pronounced. Furthermore, the breast and under-parts are white in both sexes (though slight marking may be apparent in some birds). And the impression is of lighter upper-parts, even allowing for variable lighting and distance when the photos were taken. Conveniently, there’s not much detectable difference between male and females in the respective populations.
Osprey P.h. ridgwayi
EXAMPLES OF P. h. carolinensis
EXAMPLES OF P. h. ridgwayi
I’m going to stick my neck out here – I’ve not seen this mentioned anywhere, and I need to do some more comparative research. When I saw Barbara’s pair of photos, I immediately noticed that the eyes of the P.h.r were paler than the bright orangey-yellow of P.h.c. This distinction carries on through the comparative photos above: the P.h.cs were photographed in Florida and further north and have strikingly vivid eyes. The P.h.rs were photographed on Abaco and Grand Bahama at different times by different people. All have noticeably paler irises, more a light greeny-yellow.
I’d welcome any views on this rash amateur theory. Preferably supportive ones…
UNDERWING DIFFERENCES
There’s a further comparison that can be made with the two subspecies in flight. Without going into technical and linguistic detail, the underwings of the P.h.cs are much darker than the Bahamas birds, whereas P.h.rs are notably paler and in some cases mostly white. As an example, below is a distance shot I took when bonefishing out on the Abaco Marls, using a pocket camera. This is definitely a local bird! Compare with the dramatic image below it, where the strong darker markings are all too evident. It’s a great shot with which to bring the lesson to an end.
Photo credits: Tom Sheley (1); CWFNJ (2); Barbara Crouchley (3, 4); Danny Sauvageau (5, 6, 7); Jim Todd (8); Linda Barry Cooper (9); Woody Bracey (10); Keith Salvesen (11); the inimitable Northside Jim (12); Cute-toon, Birdorable. Thanks for all use permissions – also to Steve Connett for the idea!
Anyone who has watched – and indeed heard – the behaviour of new chicks in a nest will recognise what is going on here. Four tiny Northern mockingbird chicks are passive and apparently dozy in the nest while they wait for one or other parent to fly back to fill their little faces.
As soon as they see or sense the imminent arrival of parent, the clamour begins. Me me me. Feed me first. “Fill-a-mi-beek”. Straining and craning forwards and upwards, with gaping yellow mouths. Pushing and shoving for optimum positioning. It’s all a bit frantic in that confined space.
Quite often, there’ll be a slightly smaller, less active chick at the back of the screeching pack… the best hope may be some leftovers or some food sprayed around in the mayhem. Then the parent bird flies off and the riot subsides. For a few minutes, anyway.
The 2 chicks at the back haven’t quite got the hang of the tactics yet…
The chick at the front – see him? – is out of the game..
As the photographer Melissa Maura wrote of this sequence: “A local avian staple seen in every Bahamian garden – the brilliantly musical Mockingbird. I followed this diligent Mamma for a few days in Abaco continually foraging for her 4 babies. Exhausting!”
* * Title / header: from the word ‘Mama’ onwards, there’s a notable absence of the role of `Papa’ in all this. He will have been the one to choose the territory and build the nest. His work complete, he can relax a bit in the knowledge that the chicks will fledge after only about a fortnight. Any Mama can cope with that, surely? Why interfere when it’s all going so well…
