BAHAMA MOCKINGBIRD: RARE LEUCISTIC VARIANT ON ABACO

March 23, 2018 by Rolling Harbour

BAHAMA MOCKINGBIRD

RARE LEUCISTIC VARIANT ON ABACO

The header image is of a Bahama mockingbird recently photographed by keen-eyed Abaco birder Keith Kemp. It is a thing of wonder and beauty, exceptionally rare and possibly unique. I can find no other example of a leucistic bird of this species online.

This is not Keith’s first leucistic bird discovery on Abaco either – a while back he found a leucistic Western spindalis. You can read more about leucism and its distinction from albinism, and see a number of other examples of leucism including a white turkey vulture HERE

Even more astonishingly, Keith managed to get a photo of the ‘white’ bird and a ‘normal’ bird together (above). The difference is startling. Below is a fine photo by Peter Mantle of a Bahama mockingbird, as you would expect to see one – basically brown with a pale, flecked front / underside.

LEUCISM? EXCUSE ME, AND THAT IS?

I’ll recap what I wrote in the earlier post linked above. First, what it is not. It is not albinism, which results from diminished or lost melanin production that affects pigmentation. One characteristic of the condition is the tendency to pink eyes, which of course is seen in humans as well as animals and birds. For example:

Albino Fwuffy Bwunny Wabbit

WELL, WHAT IS IT THEN?

Put simply, melanin is only one of many ingredients of pigmentation. Leucism is caused by pigment loss involving many types of pigment, not just melanin. In birds this results in unnaturally pale or white colouring of feathers that may be partial or entire. The eyes of a bird with leucism are unaffected – so, not pink. At one extreme, if all pigment cells fail, a white bird will result; at the other extreme, pigment defects cause patches and blotches of pale or white on the bird, often called a ‘pied’ effect. The condition can be inherited.

KK’s leucistic Western spindalis, an example of partial or ‘pied’ leucism

So there you have it: another extreme rarity for Abaco, and a further example of how rewarding – and surprising – birding on Abaco can be. To repeat the link to the more detailed article on leucism in birds, you can find with (*distraction alert*) some music and inappositely comedic material thrown in HERE

All photos Keith Kemp except the ‘normal’ bird, Peter Mantle

LA SAGRA’S FLYCATCHERS REVISITED ON ABACO

March 22, 2018 by Rolling Harbour

LA SAGRA’S FLYCATCHERS REVISITED ON ABACO

LA SAGRA’S FLYCATCHER Myiarchus sagrae is one of 3 permanent resident ‘tyrant’ flycatchers found on Abaco, the others being the CUBAN PEWEE and the LOGGERHEAD KINGBIRD. In the summer, they are joined by another commonly-found species, the GRAY KINGBIRD. There are other flycatchers, but they are seasonal, transient or vagrant, and far less common.

Two classic LSF poses: ‘head-on-one-side’ & ‘watching-for-insects’

I have just been watching one of these frankly ~~rather~~ very cute little birds as it patiently watched me watching it. I wasn’t very close, and I kept my distance because it seemed a little wary and I didn’t want to blow the chance of a couple of photos – the familiar ‘bird-flies-off-just-as-shutter-pressed’ syndrome.

Sized between the little cuban pewee, with its diagnostic crescent eyes, and the larger loggerhead kingbird (see below), the LSF shares with them the ability to raise its crest. I was luckily able to catch this on camera – and also some singing.

As the name suggests, the species is primarily insectivore, fly-catching in the undergrowth and low scrub or ‘hawking’ from branches. However these birds also eat berries and seeds. Their call is a high pitched single or double noted sound described as ‘wink’. Here’s a Bahamian example.

Paul Driver / Xeno-Canto

The LSF’s natural habitat is coppice and rough scrubland. It builds its nest in a tree cavity or similar natural hole, and usually lays a clutch of two to four eggs. And this morning by coincidence, Abaco birder Rhonda Pearce posted a photo of a LSF nest with its eggs.

ID CONFUSION

Here are the two flycatcher species, mentioned above, that might cause confusion:

CUBAN PEWEE

LOGGERHEAD KINGBIRD

Ramón Dionisio José de la Sagra y Peris (1798–1871)

For those who may be wondering who – or what – a ‘La Sagra’ is, the answer is: a multi-talented Spanish botanist. He was also a writer, economist, sociologist, politician, anarchist, and founder of the world’s first anarchist journal El Porvenir (“The Future”). At one time he lived in Cuba and became director of Havana’s Botanical Garden. His name lives on arguably more significantly in ornithological than in anarchist circles (actually, an ‘anarchist circle’ must surely be an oxymoron…)

[I note in passing that La Sagra is a provincial area in Spain, an Italian festive celebration, a chocolatier, or a small comet – all of which meanings may have to be negotiated online before you get to the flycatcher…]

To continue with the occasional PHILATELIC theme of this blog, here are stamps from the Cayman Islands and Cuba featuring the La Sagra’s Flycatcher. The Cuban stamp commemorates the death of Juan Gundlach, the man who chose La Sagra’s name to bestow on the LSF. The colouring is… somewhat unrealistic!

Credits: All photos Keith Salvesen except nest (Rhonda Pearce) and loggerhead kingbird (Mrs RH); recording by Paul Driver / Xeno-Canto; stamps O/S

AGGRO ON ABACO: ‘PARROTS OF THE CARIBBEAN’

March 19, 2018 by Rolling Harbour

AGGRO ON ABACO: GOTCHA!

‘PARROTS OF THE CARIBBEAN’

Mmmmm… gumbo limbo berries at Bahama Palm Shores. My favourite evening snack as we parrots head south to the National Park in the evening.

There’s a flock of about 60 of us tonight. I hope I’m left alone to get stuck in – there are plenty of trees to choose from here…

Uh oh! That was never going to happen. We are a noisy rowdy gang, and no one gets to eat alone for long…

This is really bad news… this guy’s hungry, and he’s swooped in higher up the branch, so he’s got an advantage.

Time to take a stand. I’m getting on a level with him. I was here first – these are MY berries… But he’s getting shouty. And there’s aggro in the air…

Right, I’m backing off here. I never did much like gumbo limbo berries, now I come to think of it… And he looks mean as hell. But wait – I’m not just going to back down. Let’s give him a little surprise to remember me by.

GOTCHA!

Photo sequence taken at BPS (North) around 17.00, when often the parrots flock to the gardens and surrounding coppice on their way home in the south of the island; raucous recording also made at BPS on an earlier visit. All ©Keith Salvesen

LEAST BUT NOT LAST: TINY SANDPIPERS ON ABACO

March 12, 2018 by Rolling Harbour

LEAST BUT NOT LAST: TINY SANDPIPERS ON ABACO

Least Sandpipers Calidris Minutilla are the smallest ‘peeps’ to be found on Abaco. There are plenty of other sandpiper species, but none so tiny as these. Take a look at the image above. See them? All 3 of them? Just look at their size in comparison with the mangrove stems.

I took these photos from the sharp end of a skiff a few days ago, way out on the Marls and with a fishing rod tucked under one arm. We were on a drift along the shoreline, and these little guys were foraging on the water’s edge as we silently floated past.

They were quite unperturbed by our presence, being far too busy feeding to be bothered with us. I have usually seen these little birds on the beach, busy in the wrack-line rootling out goodies. There, they look very small – but not nearly as tiny as when foraging among the mangrove stems.

I debated whether to do some cropping to magnify the details on the page, so to speak, but then I decided that these very sweet creatures deserved their own space without the indignity of close inspection. Context is all.

These mini-sandpipers may be Least by name, but they are very far from last in my personal list of favourite peeps. There are some down on the beach right now, but there’s some cloud cover today… I’ll wait for the sun to catch them in the best light.

SPOT THE LEAST SANDPIPER

All photos: Keith Salvesen

BUTTERFLIES ON ABACO (10) : HAMMOCK SKIPPER

March 8, 2018 by Rolling Harbour

BUTTERFLIES ON ABACO (10)

HAMMOCK SKIPPER

The Hammock Skipper Polygonus leo is quite a small butterfly. We found the ones shown here in the vegetation at the back of the Delphi beach. Having initially thought this was a Northern Cloudywing (and a ‘lifer’ for me), Colin Redfern has kindly corrected my (mis-)ID, and I have made the consequent changes.

Hammock Skipper - Polygonus leo, Abaco Bahamas (©Keith Salvesen)

Perhaps unusually for butterflies these skippers are sexually ‘monomorphic’, i.e. very similar in both sexes. Males and females both have completely dark brown wings except for the small white spots.

We noticed that the spots and patterns were (again, unusually?) not symmetrical as between the wings. [That should probably be ‘not reflectively symmetrical’, as with a Rorschach inkblot.]

All photos, Keith Salvesen; timely ID correction courtesy of Colin Redfern…

ABACO CHECKLIST: 40 BIRDS IN A DAY

March 5, 2018 by Rolling Harbour

ABACO CHECKLIST: 40 BIRDS IN A DAY

South Abaco – the whole area south of Marsh Harbour – provides by far the best birding opportunities for a day of varied birding. A recent party led by birding guide Reginald Patterson included Charmaine Albury in the enthusiastic team. She sent me their checklist for the day – 40 species covering an impressive range of bird types. Here is the list, to which I have added some illustrative photographs.

BAHAMA PALM SHORES

1. Blackfaced Grassquit
2. Greater Antillean Bullfinch
3. Red-winged Blackbird
4. Gray Catbird
5. Abaco (Cuban) Parrots
6. Painted Bunting
7. Northern Mockingbird
8. La Sagra’s Flycatcher
9. Cuban Pewee
10. Yellow-throated Warbler

11. Western Spindalis
12. West Indian Woodpecker
13. Cape May Warbler
14. Ovenbird
15. Eurasian Collared Dove
16. Common Ground Dove
17. Bananaquit
18. Red-legged Thrush
19. Turkey Vulture
20. Cuban Emerald Hummingbird
21. Thick-billed Vireo

BPS Duck Pond

22. Blue-winged Teal
23. Green-winged Teal
24. Common Gallinule

SAWMILL SINK BLUE HOLE

25. Olive-capped Warbler
26. Yellow-rumped Warbler
27. Loggerhead Kingbird
28. Prairie Warbler

HIGHWAY ROADSIDE

29. Bahama Warbler
30. American Kestrel

GILPIN POND

31. White-cheeked (Bahama) Pintail
32. Great Egret
33. Great Blue Heron
34. Tricolored Heron
35. Lesser Yellowlegs
36. Solitary Sandpiper

SANDY POINT

37. Laughing gulls
38. Ruddy turnstone
39. Sanderlings
40. Royal terns

The checklist covers a broad range of birds that you might expect to see in habitats ranging from coppice to pine forest to water to shoreline. Most are permanent residents, with some winter residents (eg the painted bunting, Cape May warbler). Abaco specialities include the parrots of course, the West-Indian woodpecker and the olive-capped warbler.

And birds that might, on another day, be seen? Maybe the endemic Bahama Woodstar hummingbird and the endemic Bahama Swallow. At Gilpin Pond, black-necked stilts and perhaps a belted kingfisher. And at Sandy Point, brown pelicans fishing off the dock and the chance of white-tailed tropicbirds off-shore. But overall a ’40 day’ is a great day!

We are just back on Abaco last night, and without actually trying – and just from the balcony in about 20 minutes – we have scooped:

Turkey Vulture, Black-faced Grassquit, Bananaquit, Bahama Swallows, Loggerhead Kingbird, La Sagra’s Flycatcher, and Thick-billed Vireo – also Oystercatchers heard from the beach. Time to investigate further…

Credits: Tom Sheley (1); Keith Salvesen (2, 5, 8, 9); Craig Nash (3); Gerlinde Taurer (4, 6); Tom Reed (7); Nina Henry (10)

BAHAMAS REEF FISH (44): PORKFISH

March 1, 2018 by Rolling Harbour

BAHAMAS REEF FISH (44): PORKFISH

Behold the porkfish Anisotremus virginicus, the slightly unattractively named representative of the (arguably) even less attractively named grunt species. These small, bright-coloured reef dwellers are rarely more than 12 inches long. They are mainly nocturnal fish, feeding on small crustaceans, mollusks and so on. Juveniles have been observed acting as cleaners to larger species, feeding on parasites – an example of mutualism between species, in which both sides benefit from the arrangement.

WHY IS A ‘PORKFISH’ A ‘GRUNT’

The terminology seems to be somewhat confused by local usages, but in general terms all porkfish are grunts; but not vice versa. Yet I notice that the term ‘porkfish’ is used to describe other types of grunt. A good rule of thumb is the the Atlantic Porkfish is the only grunt with two black vertical bars and yellow stripes… Note that grunts differ from their cousins the snappers by having a different dental arrangement – no canine teeth.

AND WHY ‘GRUNT’ ANYWAY? DO THEY SOUND LIKE PIGS?

Well, perhaps a bit. All grunts, including porkfish, are capable of producing grunt-like sounds from some kind of grinding of their back teeth that is too technical to go into here**. The sound is associated with ‘situations of duress and danger’ – such as being caught and unhooked…

DO YOU HAPPEN TO HAVE A RECORDING?

As it so happens I do. This is taken from a rather longer Youtube video in which a grunt was caught, unhooked and returned.You’ll hear a couple of grunts as the fish was unhooked, and some (perhaps understandable) hilarity on the boat. I guess you had to be there.

Porkfish are gregarious, and also mix with other species Porkfish (Grunt), Bahamas - Melinda Riger / Grand Bahama Scuba

ARE PORKFISH EDIBLE?

Like most if not all grunts, they are, with the proviso that there is some association with ciguatera. I’ve never knowingly eaten one myself, but I gather that “grits and grunts” is a popular culinary combo in some places. For those that might want to know more, a quick look at a couple of threads reveals the following:

They taste great, a bit like ham
Their white meat cooks very well
They taste better than black margates (another grunt species)
Eat them in enchilado or breaded fillets
‘Big-ass head’ on them so not much if you filet
If you scale and cook whole you get a better yield on them
When fishing for supper, ‘shoot ’em up and hold off for the bigger ones’

Credits: all great photos by Melinda Riger / Grand Bahama Scuba, except the last by Brian Gratwicke (wiki); soundbite from Youtube video 2010 by peachyree; research from seaworld.org; britannica.com and the usual suspects…

** Subtle code for “I haven’t really understood it…”

THE ARTICULATE WHALE (1): TELLING A TALE AFTER DEATH

February 26, 2018 by Rolling Harbour

THE ARTICULATE WHALE (1): TELLING A TALE AFTER DEATH

The ‘false killer whale’ Pseudorca crassidens has a somewhat misleading name: first (as implied), it is not a killer whale; second, it’s not actually a whale at all, but a large species of dolphin. However, it does have some killer whale tendencies – attacking and killing smaller marine mammals for example – and perhaps a passing resemblance, so the species has been given something of an upgrade, name-wise.

Although these fine creatures are distributed widely around the globe, the overall numbers are thought to be small, and relatively little is known about them in the wild. They are, of course, used as aquarium exhibits but the knowledge gleaned in captivity cannot provide much of an overview of their oceanic behaviour, which remains relatively unstudied.

However, there is one source of valuable data – the scientific study of stranded animals. And as it happens, Abaconians will very soon be able to obtain at least a skeleton knowledge of the FKW, the end-product of a long and complicated research project by the BMMRO in conjunction with Friends of the Environment. Just a quick word of warning before you read further – some images below are not especially pleasant to look at, so be prepared for them… They are illustrative and not intended for close inspection (unless you want).

Exactly a year ago an FKW was reported to have stranded on Duck Cay, off Cherokee Sound. BMMRO were quickly on the scene, and hoping to undertake the usual procedure of a necropsy, in which post-mortem samples are taken for analysis. However the poor creature was in an advancing state of decomposition, so only skin samples and photographs could be taken.

Telescoping the intervening months for the sake of brevity, the decision was made to cut up the carcass (note the face-masks) and bury it where it was, so that its integrity would be preserved for later retrieval, cleaning, reconstruction (‘re-articulation’) and exhibition for educational purposes.

In December, the remains were exhumed for the next phase of the animal’s decomposition – submersion in cages in the mangroves – before the final cleaning of the bones in readiness for its re-articulation and display.

Cleaning the bones has been a meticulous process, leaving the resulting skeleton ready to reconstruct in situ at Friends of the Environment’s Kenyon Research Centre in Marsh Harbour. Adult FKWs can grow up to 6 metres long, so there are a great many bones from large to very small to place correctly – and plenty of teeth (see below). The re-articulation is nearly finished, and it is hoped that the completed skeleton will be on display in the very near future. I am planning to see it in about 2 weeks time, and – this sounds quite strange, I know – I’m very excited about it.

This ambitious year-long project has involved BMMRO, FOTE, BEP (Bahamas Environment Protection Foundation), interns, and volunteers. I am keen to know whether, in the modern way, an affectionate name has been chosen for the skeleton. ‘Duck Cay’ doesn’t provide a very promising start. Well, maybe Donald is in vogue…?

ARE STRANDINGS FREQUENT – AND WHY REPORT THEM?

Each year there may be half-a-dozen reports of cetacean strandings in Abaco waters, both whales and dolphins. As far as I can make out, the animals are almost invariably dead. If still alive, reporting is clearly urgent to ensure a quick response and to maximise the creature’s chances of survival. If dead, a carcass can provide scientists with valuable data on the biology and health of marine mammals and, in turn, the health of our marine ecosystems. This includes basic information, such as an animal’s age, its size, the types of prey it consumes, and the occurrence of diseases. Necropsies can provide more detailed information to add to the growing knowledge-base of marine mammal populations.

And a project like this one, with its great educational potential, can in effect enable a stranded marine mammal to tell its story even after death.

STRANDING NETWORK HOTLINE NUMBER +1 242 366 4155

(or +1 242 357 6666 / +1 242 577 0655)

False Killer Whale skull, Abaco Bahamas (BMMRO)

Credits: header image, Endless Ocean / wiki; #1 NOAA; all other photos BMMRO or FOTE, with thanks; range map wiki

RED-WINGED BLACKBIRDS ON ABACO BAHAMAS

February 20, 2018 by Rolling Harbour

RED-WINGED BLACKBIRDS ON ABACO

The sounds are unmistakeable – a discordant chorus of soft chuckling noises like tongue-clicks as the RWTs flock into a bush, interrupted by harsh, metallic calls like rusty metal gate-hinges being forced open. Or maybe a lone bird mournfully repeating its eerie call from the mangroves far out on the Marls as the bonefishing skiffs slip silently along the shoreline. No other species sound quite like Agelaius phoeniceus.

The handsome males sport flashy epaulets, most clearly visible in flight or in display – for example to impress a prospective mate. Again, they are unlikely to be confused with another species.

The females, as is often the way, are less showy. I have just read that they are ‘nondescript’, which is unnecessarily harsh I reckon. Here are a couple of examples.

And the darker brown ones that are clearly not handsome black males? These are young males in their first season, before they move on to the full adult male plumage. Previously I had designated them females (as I had assumed) until very gently corrected by the legendary Bruce Hallett. Not only was Bruce an essential part in the production of the Birds of Abaco, he also keeps a benign eye on my posts and occasionally steps in to clarify IDs etc. I took the first male juvenile at Casuarina, when I also made the sound recording (below). The second was at Delphi – and with some ‘light’ issues, I notice…

Fledglings are kind of cute…

SO WHAT DO THEY SOUND LIKE?

You may need to turn up the volume a bit. You will also here a lot of dove noise and, in the background, the sound of waves lapping onto the shore.

Photo Credits: Tom Sheley (1, 2, 4, 5, 8); Alex Hughes (3); Keith Salvesen (6, 7, 9 & audio)

MANATEES IN THE BAHAMAS? WE GOTTEM!

February 15, 2018 by Rolling Harbour

MANATEES IN THE BAHAMAS? WE GOTTEM!

Not so long ago, most people had no idea that the waters of the Bahamas in general – and Abaco in particular – contained a small population of these curious, gentle, trusting creatures. When I first wrote about them and their adventures, there was surprise – maybe disbelief. A few years later, all that has changed thanks to the BMMRO and an outreach program that raised awareness – and consequently the sighting and reporting – of manatees. They are now widely recognised as they nose their way round harbours, docks and landing stages – and quite rightly they still excite delight and a degree of wonderment.

You can find out more – lots more – about Bahamas manatees on my page HERE. I have a post in progress about recent manatee developments with a rescue one but alas I have found I have already run out of week through some kind of bizarre time / space continuum dislocation (specifically, flagrant time-mismanagement). So I am posting a few adorable images to be going on with.

And remember, if you happen to see one, please do report it to the BMMRO or let me know. Useful data includes date, location and a description if possible of any damage – notches and nicks – to the paddle (= tail). It’s a good method for ID. Photos a bonus. Every sighting adds to the database of knowledge about these strangest of creatures of the Bahamian seas. And you’ll be pleased to know that they are undoubtedly managing to breed in the Bahamas: there are baby manatees to prove it…

All photos: BMMRO

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.

BIRD WING FEATHERS: A SIMPLE GUIDE TO THE MYSTERIES

February 9, 2018 by Rolling Harbour

BIRD WING FEATHERS: A SIMPLE GUIDE TO THE MYSTERIES
Thanks to the excellent ‘Myr’s Bytes’, say goodbye to ‘what’s the difference between primary & secondary feathers’ misery… This could be the clearest illustration and explanation of a bird’s wing you or I will ever see.

Myr's Bytes

It has been a while since I participated in Draw a Bird Day. I was happy to see some bird drawings in my blog reader this morning and decided to get inspired. I’ve been mostly sketching lately and none of the results have looked quite showable. But I did have a partially coloured drawing of some bird wings. And now, it’s fully coloured!

When I look at open and folded wings in bird photos, I often wonder – how do they fold and which feathers go where? John Muir Laws came to the rescue! The Laws Guide to Drawing Birds explains all this with beautiful illustrations. My two wing drawings are based on his illustrations of a passerine wing (dark grey with two white wing bars… I don’t know the species… some kind of flycatcher???). I did a good job of illustrating the layout of the different feather groups, but…

View original post 199 more words

BAHAMAS REEF FISH (43): CUBERA SNAPPER

February 8, 2018 by Rolling Harbour

BAHAMAS REEF FISH (43): CUBERA SNAPPER

The cubera snapper (Lutjanus cyanopterus) is the largest snapper species. Adults may grow to 5′ long but they average around 3′ long and weigh 40 lbs or so (the record apparently stands at a massive 126 lbs). These are game fish, and they are a commercially important species. They are also IUCN listed as vulnerable, perhaps for that very reason.

10 CUBERA SNAPPER SNAPPY FACTS

The largest of a large number of snapper species in the western Atlantic
Feed on fish, shrimps & crabs, with large strong teeth (see pics) and jaws
Among their (few) predators are sharks, barracuda, and moray eels
Edible, but beware of the danger of CIGUATERA poisoning
In summer months, spawning is governed by lunar cycles
Cuberas form huge spawning masses (to 10k) in offshore shallows
Sadly the resulting eggs and larvae are rich pickings for predators…
Youngsters live in sea grass or mangroves for protection
Cuberas are game fish with commercial importance
IUCN listed as vulnerable – largely courtesy of mankind (see »)

RANGE FINDER

CONSERVATION MATTERS

Overfishing is one of the greatest threats to the species. Those young fish that are not predated naturally and grow to adulthood are targets for fishermen. There’s no prissy ‘catch & release’, as with bonefish. At spawning time, as the fish instinctively (and predictably) mass as the moon dictates, so do the human predators. The spawning sites are where the best protection can be given, to ensure the annual reproductive cycle is uninterrupted. If not, ‘vulnerable’ will soon give way to ‘endangered’…

I’d been going to pull apart a long recipe for the “wonderfully sweet white meat ” of this fish for the tastiest morsels of info, then (not being a cook) I quickly tired of the idea. Sorry to disappoint.

Credits: Melinda Riger for the wonderful photos; range map from wiki; magpie research pickings, including (but not limited to ) Nat Geo

COOKIECUTTER SHARKS: BEASTLY LITTLE SUCKERS

February 5, 2018 by Rolling Harbour

COOKIECUTTER SHARKS

BEASTLY LITTLE SUCKERS

The Cookiecutter shark Isistius brasiliensis (aka the less scary, more genial sounding ‘cigar shark’), might be an ideal candidate for a Room 101 nemesis.** These little beasts – a species of dogfish shark – are found in several mainly island-based areas dotted around the globe, including in Abaco waters.

HOW COME THE NAME?

These sharky little b@st@rds (*technical term*) attack marine mammals and fishes, gouging out perfect round plugs of skin and flesh, leaving what are sometimes called ‘crater wounds’. Then they eat them. Imagine getting hold of a really sharp domestic cookie cutter with circular rows of razor-sharp teeth, and grinding it hard into your thigh. There! That!

The size of an adult shark:16″ max

The term ‘cookiecutter’ is also a pejorative slang term, meaning mass-produced, lacking in originality, or boringly samey, as in cookiecutter cars or TV genres etc. The little critters under consideration here are anything but…

HORRIFYING COOKIECUTTER FACTS

Live in the depths, rise vertically in the day & dive back down at dusk
Undersides have light-emitting ‘photophores’ which emphasise…
…the dark collar which acts as a lure, resembling a small innocent fish
Bioluminescence lures prey & confuses predators (more on this below)
The glow is so strong it may last for some time after removal from water

Their lips are ‘suctorial’ = they attach tightly to their target
The jaws then gouge out the victim’s flesh in a remarkably neat circle
Omni-vicious: any medium to large ocean creature is vulnerable to attack
There are even occasional reports of humans being targeted

Here are two Blainville’s beaked whales that I photographed from the BMMRO research vessel. The top whale has a number of circular healed attack marks and a recent one. You can see how deep the gouged hole is. The other has well-healed scars.

Multi-toothed: top rows of small teeth, rows of larger teeth on the bottom
The lower teeth are the cutters, acting like a saw when locked on
See header image and below for full details

HOW EXACTLY DO THEY DO WHAT THEY DO?

I can explain it no better than the renowned authority Prof. W. K. P. Dear: “the suctorial lips ensure a tight seal. It then bites, using its narrow upper teeth as anchors while its razor sharp lower teeth slices into the prey. Finally, the shark twists and rotates its body to complete a circular cut, quite possibly aided by the initial forward momentum and subsequent struggles of its prey. The action of the lower teeth may also be assisted by back-and-forth vibrations of the jaw, a mechanism akin to that of an electric carving knife”.

ARE THESE SHARKS ‘PARASITES’, WOULD YOU SAY?

The behaviour of these sharks is an example of a symbiotic relationship between two species that is parasitic. This means essentially that one gains and the other suffers (e.g. no-see-ums!). This is distinct from commensalistic symbiosis, where one species gains and the other is unaffected (e.g. cattle egrets with cattle); and mutualistic symbiosis, where both gain (e.g. cleaner fish & groupers). So, in a word, yes.

An ‘ambush predator’: they ‘hover’ in the water column waiting…
They are capable of rapid movement to catch up & latch onto prey
They will eat a passing small fish, crustacean or even squid as a snack
Sometimes they operate in schools; there is safety in numbers
The schools are thought to increase the ‘lure’ effect of the dark collar

A beached whale that’s been heavily targeted

FUN FACT TO COUNTERACT THE BAD STUFF

In the late c20, more than 30 U.S. Navy submarines were forced back to base to repair damage caused by cookiecutter shark bites, either to the neoprene footings of sonar domes or to rubber-sheathed cables. The problems were solved by using fibreglass. Oceanographic equipment and telecommunications cables are also recorded as being damaged by these sharks.

Cookiecutter Shark – the real deal

MONSTERS OF THE DEEP

These great cards from the weirdly spelled WIERD ‘N’ WILD CREATURES provide excellent factual info. Their CCS card is no exception. You’ll find more details here about the effect of the bioluminescence and so on, written as clearly as I might hope to.

** “The worst thing in the world varies from individual to individual. It may be burial alive or death by fire, or by drowning, or by impalement, or fifty other deaths. There are cases where it is some quite trivial thing, not even fatal.” (George Orwell, 1984)

Alright now…

Credits: BMMRO – header image; beaked whale photos – Keith Salvesen / BMMRO; Te Ara NZ for the main jaw image; all small images with thanks to Wiki and respective photographers who took the time to upload them for all to enjoy & learn from; ‘wierdnwonderful creatures’ for the monster card; range map from Wiki

PS Apologies to anyone who bothered to wade through this, and stayed awake long enough to notice that formatting gremlins struck halfway through

GRAYSBY (GROUPER): BAHAMAS REEF FISH (42)

February 1, 2018 by Rolling Harbour

GRAYSBY (GROUPER): BAHAMAS REEF FISH (42)

The Graysby Cephalopholis cruentata is a small, spotty grouper, which grows to a maximum of around 16 inches. These rather unassuming and solitary fish have a preference for coral reefs, where they can blend in with their surroundings on ledges and in caves and crevices during the day. At night, they become active – that’s when they feed on feed on small fish, crabs and shrimps.

The graysby has variable colouring in a range from light brown to pale gray, with all-over spots that may be red, orange or brownish. Often, they have 3 to 5 contrasting spots on their backs, along the base of the dorsal fin, as below:

The long erectile dorsal fin comprises both spines and ‘rays’ – spines at the front, rays at the back. Like this:

The spots of a graysby can change in colour (at least to a limited extent), becoming either paler or darker. I imagine this is a protective feature to enable the fish to blend in more easily with its reef surroundings.

Graysby (grouper) - Melinda Riger / Grand Bahama Scuba

Signalling to turn right…

I wondered if they are edible. I believe so – but then I also read that the larger adults carry the risk of ciguatera and raised mercury levels. So I’ll give it a miss thanks.

Photo & other credits: all photographs by Melinda Riger / Grand Bahama Scuba; aqua.org; SAMFC (drawing)

BLACK-LEGGED KITTIWAKE: A RARE SPECIES FOR ABACO

January 30, 2018 by Rolling Harbour

BLACK-LEGGED KITTIWAKE: A RARE SPECIES FOR ABACO

I recently posted about the sighting of an entirely new bird species for Abaco, the CINNAMON TEAL. Almost at once, another species was sighted – not a new one, but in the next category of rarity, the V5 and V4. ‘Vagrant’ birds that have been credibly recorded on Abaco / in Abaco waters fewer than 5 times – and maybe only once – are classified as V5 or ‘accidentals’. Birds seen a few times more than that, but irregularly and unpredictably (‘casuals’) are V4s. One such is the fine black-legged kittiwake, also known as the seahawk and a close relative of gulls.

During the Abaco Christmas Bird Count in December, avid birder Keith Kemp and a small group were checking the beach at Crossing Rocks. In due course he uploaded a list of birds seen, with selected images, to the excellent eBird site. This included a royal tern. Or make that “royal tern”.

It wasn’t long before sharp-eyed Bruce Purdy from Cornell contacted Keith to say “You shot a picture of an adult non-breeding black-legged kittiwake!!!!!!!!”. This was confirmed by Bruce Hallett, author of the definitive field guide to the birds of the Bahamas.

As Bruce Purdy commented:

“This is the first kittiwake reported that I know of in the last 20 years. Tony [White] shows a few reports but I don’t know if they were documented. Probably not since most people just started carrying cameras, so you may have the first documented kittiwake… It is a great find”.

So you are looking at (almost certainly) the first photographs of a kittiwake ever taken on Abaco. Actually, make that the Bahamas – no others are shown on eBird for the whole region; the nearest being a handful of sightings on the Florida coast.

STOP PRESS Keith’s sighting was in December 2017. The very day I pressed ‘publish’ on this post, January 30, two people immediately contacted me to say they had seen this bird in the Crossing dock area in Marsh Harbour! Thanks to Philip Sawyer and Nancy Albury for their sharp eyes and immediate response. Neither managed to get a photo, but two independent witnesses on one day in the same location make for a compelling ID. I imagine this is the same bird (rare enough as a single – the first in over 20 years – so exceptionally unlikely as a pair). Maybe there are rich fish pickings to be had in the MH harbour area.

Any further reports would be most welcome; a photo would earn the theoretical Kalik reward…

These kittiwakes are a pelagic species, birds of the open sea. They spent most of their time over the ocean, where they live on fish. However, they return to land to breed – often on cliffs, and in large, noisy, nesting colonies. Here’s a very short idea of what that might look and sound like.

Keith’s Kittiwake was way out of its normal range. This map shows just how far.

I always like to include an image of a species under discussion, as it was depicted by one of the early pioneers such a Mark Catesby or (as here) Audubon.

I’ll round off the story with another great source for comparative images – especially as between sexes, ages and seasons – the Crossley guide. The image below comes from the guide to Britain & Ireland, where kittiwakes are not uncommon locally where there are cliffs. Keith’s bird was in winter (non-breeding) plumage, as seen below, top left.

Credits: Dick Daniels / carolinabirds.org (1); Yathin S Krishnappa (2); Keith Kemp (3, 4, 5); RSPB Britain (video); Audubon (OS) (6); Crossley Guide (OS) (7); range map Wiki

AWESOME HURRICANES & MAGNIFICENT FRIGATEBIRDS

January 25, 2018 by Rolling Harbour

AWESOME HURRICANES & MAGNIFICENT FRIGATEBIRDS

‘Awesome’ in its original (and biblical) sense of ‘inspiring awe and fear’, I mean – as with hurricanes; not as in ‘awesome cupcakes’. And Magnificent because that’s what frigatebirds effortlessly are.

This post is about the resilience of birds after extreme weather events, and their powers of recovery. As we all recall, last autumn large areas of the Caribbean region were devastated by those twin furies, Irma and Maria. Islands that received direct hits from these destructive hurricanes were trashed with unimaginable ferocity, at a massive human, infrastructure and ecological cost from which slow recovery is still in progress. Barbuda was one of those islands.

This is the heartening story of a colony of frigatebirds on Barbuda, where in the aftermath of the storms BirdsCaribbean members offered to survey the effects of the storms in terms of the natural history of the region. These included Frantz Delcroix and Eric Delcroix, who spent time on Barbuda in mid-October, 6 weeks after Hurricane Irma.

Their assignment was to visit Codrington Lagoon, Barbuda, to carry out a survey of the Magnificent Frigatebirds to check how – or if – the sanctuary and its population was recovering six weeks after Hurricane Irma hit. The boat trip to the colony must have been tense; there might have been little or no colony left to survey.

As they neared the location, and to their delight, they saw hundreds of frigatebirds in flight, with bushes adorned with the bright red gular pouches the males. In all they estimated 1,710 frigatebirds were in the colony. In a count of seven bushes alone, 279 birds (83 females and 196 males) were counted. Amazingly, 90% of the females were on nests and some of the birds were observed courting and mating, with males even carrying nest materials.

Before the hurricane, the 4,000–5,000-strong frigatebird colony had chicks in the nest. Surveys just after the hurricane found no surviving chicks and only around 300 birds. Now, one and a half months later, there were more than 1,700 frigatebirds starting a new breeding period with almost all of the females nesting!

The team were of course deeply affected by the damage and desolation on Barbuda, and the suffering of its people. In a purely environmental context, the frigatebirds were a small sign of hope. As was noted at the time, “witnessing the power of nature—its ability to inflict such damage, but also how it can quickly rebound—was an extraordinary experience. So, we did not leave without hope. Nature is resilient!“

BirdsCaribbean is an excellent and wide-ranging organisation that deserves support. You can ‘like’ it or follow it on FB HERE, sign up for regular emails, volunteer to get involved or donate on the website HERE, and maybe even consider a contribution to its ongoing hurricane recovery efforts HERE.

Special thanks to Frantz Delcroix and Eric Delcroix for permission to use some of their wonderful photos taken during the survey; and to use parts of their review (with some adjustment to apply to the specifics of this post). Many thanks also to Lisa Sorenson, Executive Director of BirdsCaribbean, for her kind support whenever the occasion has arisen!

SEVEN NEW BIRD SPECIES ON ABACO

January 22, 2018 by Rolling Harbour

Black-bellied Whistling Duck (Keith Salvesen)

Black-bellied Whistling Duck June 2014

SEVEN NEW BIRD SPECIES ON ABACO

THE BIRDS OF ABACO was published very nearly 4 years ago. At the time, the checklist of species recorded for Abaco at the back of the book, so meticulously compiled by Tony White and Woody Bracey, was definitive for as long as records have existed (in practical terms, since 1950). The final new species included in the book was a Black-browed albatross amazingly spotted in Abaco waters from the BMMRO research vessel by a keen-eyed intern the previous summer.

Brown Thrasher (Manjith Kainickara - Wiki)

Brown Thrasher Nov 2014

Within 3 months of publication, the checklist had been rendered out of date. A totally new species had touched down on Abaco – a small flock of 6 black-bellied whistling ducks. They worked their way up South Abaco from down by Crossing Rocks up to MH Airport via Schooner Bay, Delphi and Bahama Palm Shores. By then, numbers were down to 2. Soon even they disappeared, heading presumably from wherever the flock had intended to go in the first place. Maybe they got tired en route. Maybe their internal Satnav suffered a collective failure. Maybe senior BBWD had had a bright idea for a shortcut…

Masked Booby January 2015

We are not talking here of rarities in global terms, but species that have never been seen before on Abaco. Or, if seen, went unremarked. Or, if remarked, without awareness of the significance! The advent of the current enthusiasm for birding in the Bahamas plus the ease with which a quick photo can be taken – on a phone for example – as evidence of a sighting and to aid a clear ID, may well increase the number of new species sightings in the future.

Pearly-Eyed Thrasher, Treasure Cay, Abaco (Woody Bracey)

Pearly-Eyed Thrasher March 2015

There’s the added benefit from the ease with which photos can be taken and distributed – people will no longer have to do any of the following:

Shoot birds and take them as samples (hello, J.J. Audubon & historical cohorts)
Pack a sketch pad & crayons to draw birds before they fly away (or from memory)
Rely on scribbled notes made in low light and a light drizzle
Listen to, or read, a query about a “sort of brownish medium sized bird with maybe a bit of yellow on the wings, and a black tail I think, but I didn’t get a very good look and oh yes it had sort of beady eyes and sounded a bit like ‘Kalik Kalik Kalik’ “.

Buff-breasted Sandpiper, Abaco (Keith Kemp)

Buff-breasted Sandpiper Oct 2016

Over the 4 years, there have been a few birds that, although not ‘first evers’, are second or third ever – and the first ones with supporting photos. These include the fabulous scissor-tailed flycatcher; and the bald eagle that was sighted several times over south Abaco last year. I’ll return to these rarities another time. Let’s see the sixth new bird, from late last year.

Scaly-naped pigeon (Dick Daniels / carolinabirds.org wiki)

Scaly-naped pigeon Nov 2107

To complete the set, so to speak, 2017 ended with another gorgeous duck, the cinnamon teal. You can read more about all these birds using the following links to the relevant posts.

Cinnamon Teal (Dick Daniels / carolinabirds.org)

Cinnamon Teal Dec 2017

Credits: Keith Salvesen (1); Manjith Kainickara (2); Duncan Wright (3); Woody Bracey (4); Keith Kemp (5); Dick Daniels / carolinabirds.org / wiki (6, 7)

OSPREYS: ID GUIDE TO THE BAHAMAS SUBSPECIES

January 18, 2018 by Rolling Harbour

OSPREYS: ID GUIDE TO THE BAHAMAS SUBSPECIES

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). Thanks for all use permissions – also to Steve Connett for the idea!

WTF? (WHAT’S THAT FISH?) 14: ARROW CRABS

January 16, 2018 by Rolling Harbour

WTF? (WHAT’S THAT FISH?) 14: ARROW CRABS

It’s been a while since the last in the WTF? series, which is dedicated to the wilder, less conventionally fish-shaped side of reef life – those creatures that you may come across, blink into your face-mask, and silently mouth the words ‘What’s That Fish?’ (that’s what it looks like you are saying, anyway).

Let’s meet some Arrow Crabs Stenorhynchus seticornis, one of the very few creatures surely to have a triangular body plus a huge pointy nose (rostrum), supported on long skinny legs. To which add, they wear tiny blue gloves on their two front claws.

These crabs are coral reef dwellers and mostly stay concealed during the day. Their body is protected by a carapace, and the rostrum has serrated edges like a tiny rasp or file. I haven’t found a definitive reason for this gadget, but I suspect it is more for probing than for piercing or fighting.

There’s a considerable colour variation among these crabs, as these images show. The body may even have blue iridescent lines (#2, above). And those claws may be any of 50 shades of blue…

Arrow crabs are most active at night. They eat feather-duster worms (illus.) and similar invertebrates such as bristle worms.

Feather-duster worm (Melinda Riger / G B Scuba)

Arrow Crab Meal

Like certain types of shrimp, they also have a symbiotic relationship with anemones, whereby they make use of an anemone to benefit from the food it captures – and possibly for cover too. They are protected from anemone stings, whereas some of their predators are not.

This was the place where I was going to tell you about the arrow crab’s private life, but, well… “it’s complicated”. Briefly it is: male passes sperm-filled capsule to female; she uses it in some way whereby it fertilises her eggs; she then ‘broods’ the eggs in one of her ‘swimming legs’; the eggs hatch into larvae and swim off to eat plankton; each one then grows & moults, repeating the process until it has reached adult form. On balance, humans have arguably perfected a preferable method.

Arrow Crabs are apparently popular aquarium creatures, although they sound to me rather a disagreeable challenge. They can move quickly on those long legs, and it seems as if they inclined to be aggressive to other inhabitants of the tank. As far as I can make out, it’s best not to put 2 of them together: they certainly won’t be doing the sperm capsule thing described earlier…