Mangroves, The Marls, Abaco, Bahamas (Keith Salvesen, Rolling Harbour)


For some time now, there has been understandable concern about the increasing evidence of mangrove die-back in the Abaco Marls and elsewhere in Abaco waters. Scientific investigations are ongoing and you will find some of the survey results so far on the excellent Abaco Scientist interactive map HERE. You’ll find other relevant and authoritative mangrove material if you check out the BLOG menu of the website.
Abaco - The Marls

The ‘200 sq. miles’ in my map is debatable, depending what one includes. Other estimates are of 300 or even 400 sq. miles. Whichever, the Marls cover a massive area of mangroves, islets, flats, channels and wonderfully diverse wildlife. A large proportion of the many species – fish, birds, turtles etc – depend on the complex ecology of the mangroves for food, shelter and breeding. Depletion of the mangroves from whatever cause will have a direct effect on the creatures of the Marls.

Stingrays Abaco Marls 6

Ryann Rossi, a PhD student with North Carolina State University, has been researching the worrying phenomenon of mangrove die-back in the Marls this summer. She has written an interesting and informative  account (conveniently in the RH ‘Facts about…’ style) that was published in Abaco Scientist last week. The blue links will take you to the ABSCI site for further information on each topic. I’m grateful to Ryann and ABSCI for permission to use the material.

Five Things to Know About the Mangrove Die-back in The Marls (at this point, anyway)

1. This die-back appears to be the result of multiple stressors acting together. Think of it in the sense of our own body – when our immune system is down, we are often more susceptible to getting sick. The same thing is likely happening to the mangroves.Mangrove Die-back 1 (Abaco Scientist : Ryann Rossi)

2. It appears as though a fungal disease may be taking advantage of already stressed mangroves and causing die-back. We did preliminary surveys across Abaco and found fungal lesions nearly everywhere. However, the fungus was present in different densities in different areas. In the die-back area nearly all the leaves remaining on trees have lesions. We think that this pathogen capitalized on the mangroves being weakened by other stressors such as hurricanes, which cause extensive leaf drop, change in the movement of water, change in sedimentation and erosion.

Mangrove Die-back 2 (Abaco Scientist : Ryann Rossi) jpg

3. We are still working on identifying the pathogen associated with the lesions we’ve found. We are confident that it is a fungus and are currently growing fungal cultures in the lab to examine defining morphological characteristics in addition to using DNA sequencing to identify the culprit.

4. We have documented the presence of the Robust Bush Cricket (Tafalisca eleuthera) in the die-back areas as well as other areas with high densities of lesions. These crickets are documented to consume Red and White mangrove leaves. As such, we were concerned about their potential role in die-back. We set out a caging experiment to exclude the crickets from certain dwarf Red mangrove trees to see just how much grazing they may be doing in the die-back area. This experiment is ongoing.

Mangrove Die-back 3 (Abaco Scientist : Ryann Rossi) jpg

5. The take home: there is likely more than one causal agent of the die-back in The Marls. Many factors govern mangrove productivity and functioning: nutrient availability, salinity, sedimentation rate, herbivory, and disease are just a few of the factors that contribute to overall mangrove function making it very difficult to pin point which factors may be driving the die-off. On the bright side, we are confident that we have a lead on the causes and we are working hard in the field and laboratory to fully understand what is going on in The Marls.

By Ryann Rossi|August 26th, 2015|Disease, fungus, Insects, Mangroves and Creeks, The Marls
All pics below taken while fishing on the Marls except Melinda’s shark (I’ve never got a good one)
Hawksbill Turtle, Abaco Marls (Keith Salvesen)Bonefish Abaco Marls 4Shark 4 ©Melinda Riger @ G B Scuba copyOsprey - Abaco Marls 1 Reddish Egret (White Morph), Abaco MarlsRoyal Tern, Abaco, Bahamas (Marls) 3Willet, The Marls, AbacoSouthern Stingray, Abaco Marls (Keith Salvesen 4)
FRIENDS OF THE ENVIRONMENT has also included an article on die-back by Ryann in its latest Newsletter:

Mangrove Die Off on Abaco by Ryann Rossi, NCSU

This summer Stephanie Archer and I continued research efforts focused on determining the cause of the mangrove die-off in The Marls (work funded by the National Science Foundation). Our efforts were predominantly focused on the fungal pathogen we found associated with the die-off site. We created a small citizen science and outreach project to document the presence or absence of the pathogen across Abaco. This project consisted of short surveys and leaf collections. In total, 92 areas were surveyed including locations from Abaco and San Salvador. We also took this outreach project to the annual Bahamas Reef Environment Education Foundation (BREEF) teacher training conference.  There we disseminated survey packets to teachers from islands throughout The Bahamas who will help us collect more data on the presence (or absence) of this pathogen on other Islands.

3 men on a skiff, Abaco Marls (Keith Salvesen : Rolling Harbour)

Three men on a skiff – Abaco Marls

On Abaco, we constructed an experiment to investigate the role of grazing and the presence of fungal lesions on Red mangroves. We simulated grazing using crafting scissors to cut small sections on 600 leaves in 4 different mangrove creeks. We observed the leaves for 28 days to determine if cutting leaves predisposed leaves to fungal infection. At these sites we also trapped for insects to gain an idea of what kind of grazers may be chewing on the leaves. We also did a series of disease incidence surveys that will be routinely monitored for disease progress over the next 2 years. These surveys will allow us to systematically track the progress of the disease. In addition to our field work, we spent many hours in the laboratory isolating fungi from leaves to grow in culture. These cultures were brought back to North Carolina State University and will be sequenced in order to help us identify the fungal pathogen responsible for making the lesions on the mangrove leaves.

Mangroves, Abaco Marls (Keith Salvesen)

Credits: Source material Ryann Rossi; Abaco Scientist; all photos © Keith Salvesen @ Rolling Harbour except those by Ryann / ABSCI in the main article and Melinda Riger’s cool shark




In January I posted an article called BONEFISHING ON ABACO: A CHALLENGE IS ACCEPTED. This stemmed from contact online with fisherman and fly tyer Mark Minshull, who kindly tied some flies for me to try on the Marls. In the post I showed pictures of my manky flybox and his immaculate flies. We agreed to see how things turned out while I was on Abaco in March, and  that I would report back…   


Mark 1 Specimen Bonefish Flies


We set out to test the efficacy of  prototype ‘Mark 1’ bonefishing flies in the waters of the Abaco Marls. Our testers came from the US (TC & AH), Northern Ireland (AB), and England (RH). All are proficient fly fishermen with experience of several prime bonefishing destinations between them, except for the Englishman RH who was included to add balance to the trials by adding the element of incompetence. His fly box remained an object of ridicule throughout the tests, until he resorted to using a more carefully chosen small fly box containing his most successful flies, some ‘Delphi Club Approved’ flies and the test flies. 

QUALITY All our testers agreed that the Mark 1 flies were beautifully designed and tied. As flies, their quality was rated ‘superb’; ‘bloody good’; and ‘very impressive’. As potential winners for the waters of Abaco, however, there was considerable doubt about the suitability of the pattern for colouring, shape and size.

THE TEST AREA We used the huge area of prime bonefishing territory of the mangrove swamps and sand banks on the west side of Abaco known as the Marls. Our testers were familiar with the waters and all had fished them numerous times. The sea depth, depending on tide, is a few feet at most. The consistency of the bottom is of lightweight, pale coloured mud.

Bonefishing, Abaco Marls Abaco  1

It is usually easier to look out for the shadows of the fish on the light bottom than for the fish themselves, which are often difficult to see in the water. Half-close your eyes and look at this image – the fish almost disappears, but the shadow is clearly visible. It is hard to believe the wonderful colouring of the fish until it is out of the water.Bonefish, Abaco Marls Abaco 2

THE TESTS The initial reservations of the testers unfortunately proved justified in the field. The testers all found that the fish tended not to follow the flies at all, and mostly behaved as if they had not seen them, even with the most accurate casts. The few ‘follows’ observed produced refusals of the fly at the end. Disappointingly, no fly was taken by a single fish throughout the trials.

OBSERVATIONS Our testers had some useful comments. Above all, the Mark 1 flies were undoubtedly of excellent quality and design. They simply were not suited to the waters – or the bonefish – of Abaco. TC thought they might work in Belize. It was thought that larger versions might attract permit. Overall, the Mark 1s were so radically different from the tried and tested fly patterns used successfully on Abaco that the 3 competent fishermen soon forsook the experiment and caught fish using more familiar flies. The 4th tester, lacking any finesse, might have fluked a take against the odds , but even he drew a blank.

THE PROFESSIONALS The Guides in each case had been fishing the Marls since they could walk and hold a rod. They each examined the flies, shook their heads and kept their thoughts to themselves. We interpret this as indicating a tendency for the local guides to doubt the effectiveness of the Mark 1 flies.


RH’s ‘Selected Specimen’ Fly Box

RESULTS ANALYSIS  The flies above show (front row) the 3 versions of the Mark 1 fly; (middle row) the highly effective Delphi Daddy and Delphi Diva patterns, with one random silver concoction of unknown origin; (back row) ; 2 browny / pale patterns plus a shocking pink one that the guides wisely forbade and, below, 3 roughly matching flies that brought great success even for RH this year (including 12 boated and 5 lost in one day), sourced from renowned tackle specialist E. Bay.

CONCLUSION The flies that catch the bones on Abaco tend to be pale and to have ‘streamer’ tails and / or a fair amount of sparkle. A touch of pink seems to be good. Too much pink, not so. Rubbery legs can be very effective (except in the fisherman after lunch). But lovely lifelike dark shrimp imitations are of no interest to the fish of the Marls.


  • Design and construction *****
  • Ease of use *****
  • Effectiveness for Abaco waters *

All photos RH. Thanks to Mark for creating the challenge and for being a great sport

A Box of Bonefish Flies (Abaco)

The largely ridiculous fly box of RH (most good ones removed)



Abaco Bonefish a


Here is my fly box. It is a qualified success, as is my fishing. The fly box is rather better organised than I am, though. Some of the flies in it are routinely ignored by others to whom I helpfully offer the box.  I’ve found the best plan is to stick with the silvery shrimpy patterns, especially the ones with pink heads. Then nobody gets upset. And from time to time I get lucky (see header image).

BF flies3a

Recently, a proper fisherman started to follow my blog, and I his. I immediately recognised one of the fishing lakes on his site, one where I have fished in the past. One thing led to another and I seem to have agreed to trial some of Mark’s expertly tied flies on the Abaco flats in March…

Mark’s Bonefish Patternsimage24

I am very keen on the principles of ‘Catch and Release’. So keen that I have developed my own specialist methods (designed for fishing with barbless hooks) using what might be termed ‘Early C&R’. These may include some or all of the following on any given day: 

  1.  ‘THE PHANTOM CATCH’ As the fish follows the fly, and the instant before it commits to a lunge for it, abruptly whisk the fly away from under its nose with a sharp reflex ‘trout-strike’. This will ensure that both the fish and your fly remain untroubled by actual contact. This is the most advanced form of Early C&R.
  2. ‘THE BIG MISSED TAKE’ As the fish takes your fly firmly in its mouth, become preoccupied by the fact that your left foot is planted firmly on a horrid tangle of line around your feet. You will feel the solid take, but instantly realise that your retrieve is hopelessly compromised. With some relief, you feel the line go slack as the fish shakes itself free…
  3. ‘THE REEL THING’ Hook the fish. Feel the weight on the end of the line. It’s heavy. Nice one! Turn in muted triumph to your boat partner to shout excitedly “Got One”. As you do so, allow the line somehow to snag round the rod handle and the reel simultaneously. Before you have even begun to figure how to sort this out, the fish will have released itself and be heading for the horizon.
  4. ‘THE STICKY SITUATION’ Hook the fish. Reel in confidently, keeping the line taut and the fish under your masterful control. Allow it to run if it wishes. Proceed with the same efficiency until you notice a single mangrove stem sticking out of the water 30 feet away. Using your skill, ensure that the fish suddenly has the chance to move to the other side of the stick, winding the leader or line (either will do) round it. Prepare for the ‘twang’ when the inevitable break occurs.  Your fish is away.
  5. ‘THE MANGROVE SWAMP’ Hook a fish. Play it competently until the moment your boat partner or guide gives you some word of encouragement or (worse) praise. Immediately, permit the fish to make a fast break for the nearest clump of mangroves even if it is over 100 feet away. The consequent entanglement round the myriad stems will be sure to lose you the fish and your fly. NOTE: all third party encouragement will diminish after this form of EC&R. Praise will not be repeated.


Mark has just made a challenge public on his website in a post called  All aboard for Abaco! “This little packet of flies is destined for the Bahamas… What stories will they conjure up in time? Rolling Harbour, Abaco… All will be revealed in time! Thanks in advance to RH – I will keep everyone posted in due course! Looking forward to some beautiful pictures of Bonefish…” The flies in question are shown below. It is expected that they will prove to be effective. The expectation is Mark’s. My own feeling is more one of hope. I hope he knows what he is doing. I hope I know what I am doing.*

Rolling Harbour, Abaco... All will be revealed in time!

*The plan is to ask my boat-partner and guide – anyone with access to a rod, really – to “have a go with one of these little guys”. They are far less likely to be as skilled as I am at Early C&R, and are therefore far more likely to boat a fish. Job done…

Photos: RH, 1st two; the rest by Mark


Wilson's Plover, Abaco 12


This is the second of three vaguely planned posts about these delightful shore birds. They aren’t rare but they are approachable and fun to watch. During the nesting and hatching season, there may even be some gorgeous chicks on a beach near you (a phrase I never thought I’d find myself using). PART ONE identified the typical male and female adults found on the Delphi beach almost any day. 

Nettie's Point, Abaco - Trucks & Skiffs

This post is about nest protection. Not the ingenious methods of  the birds themselves, that will come next time. This is a story of protection by humans. The photograph above shows Nettie’s Point, one of the launching points for bonefishing skiffs being taken out to the Marls, a vast area of sea, low sand banks and mangroves where the fish are found. You hope. The skiffs gain access to open sea via an artificial channel carved out of rock. The early morning trip along it is one of the most exciting part of a fisherman’s day, as he or she sets out with a clean score sheet, a rod and a box of flies. And a cooler box with some food and maybe a Kalik beer or three.

Nettie's Point, Abaco - the cut to the sea

This June, a pair of plovers decided to locate their nesting ‘scrape’ right in the middle of the cleared area where the trucks normally turn. This was by no means a wise home-planning decision, and they might well have found themselves being promptly relocated. Or (worst case scenario) ending up under a large Toyota. But not a bit of it. Instead, these small birds were looked after by the guides like this: Nettie's Point, Abaco - Plover's nest protection

A makeshift castle was built all round the nest to protect it from any inadvertent truck-related tragedies. Meanwhile the male plover stood guard outside the castle, amiably watching the human activities. Nettie's Point, Abaco - Male Wilson's Plover guards nest

I kept my distance but in fact he was quite unperturbed, perhaps sensing that we were not a threat. He still kept a beady eye on the proceedings, though.Nettie's Point, Abaco - male Wilson's Plover guards a nest

Meanwhile, what of the wooden enclosure itself? At first glance, there didn’t look much to report. However, if you look in the centre of the picture, you’ll see the female peeping out from the nest.Nettie's Point, Abaco - Nest protection 2

I very slowly moved nearer, prepared to stop if the male became agitated, or if the female shifted her position. Both seemed quite relaxed, so I took a couple of shots and walked away to leave the birds in peace. Then I went fishing.Nettie's Point, Abaco - Female Wilson's Plover on NestNettie's Point, Abaco - Mrs Wilson's Plover on the nest

As a postscript, Nettie’s Point is the location of a remarkable geographical phenomenon, possibly the result of the cutting of the channel. Along one part of the cut, for about 30 feet, the water level sinks alarming in the middle, while remaining normal at each side. Then it levels out again. This remarkable mid-stream aquatic depression is quite disconcerting to motor through on a skiff, though eventually one gets used to it. Nettie's Point, Abaco - channel water phenomenon(Note: not every fact in this post is 100% true. If you have some salt handy, take a pinch)


Royal Tern Crowned


I posted briefly about ROYAL TERNS (Thalasseus maximus) on the Abaco Marls earlier this year HERE. Yesterday’s news from the Lindo Wing (anti-Monarchists look away now) surely justifies a few more photos of these fine and noble seabirds. Everyone else is using the event to sell newspapers / magazines / products (‘Royal’ Baby Lotion – so gentle, so soft – fit for a future King’s delicate…’ etc etc). If there’s a cheerful bandwagon passing, why not just hop on? I’ll skip the info about the range and nesting arrangements of these birds and show some them in all their glory, posing in the sunshine on a dead tree way out in the Abaco Marls.

Royal Terns Abaco (2) 4Royal Terns Abaco (2) 6 Royal Terns Abaco (2) 5 Royal Terns Abaco (2) 3 Royal Terns Abaco (2) 2 Royal Terns Abaco (2) 1PS No terns were hurt trying to get the yellow crown to fit one of them. In fact, they rather enjoyed it…



Willets (Tringa semipalmata) are large sandpipers, familiar as shore birds, foragers on sand bars and mudflats, or out in the mangrove swamps. Some might describe them as quite solid and plain to look at. Until they take flight, when their gorgeous wing patterns are revealed.

willet ©Greg Page @ Cornell Lab

Willets are ground-nesting birds, often breeding in colonies. They use their stout bills to forage on mudflats or in shallow water for insects, crustaceans, marine worms and occasionally plant-life. They tend to keep their distance, and in the past I have only managed this sort of unimpressive snapshot, not least because I normally only take a small basic camera out on the water in case it – or I – should fall in.Willet, Abaco Marls 1

However, we recently fished from the prow of a skiff parked on a sandy spit on the Abaco Marls, as bonefish came past on the tide. It was a productive hour for my boat-partner, though frankly less so for his boat-partner… As we fished, and to our surprise, a willet landed of the point of the spit to feed, and gradually worked its way towards us seemingly unconcerned by the skiff, by us or by the fish action. It started off about 30 feet away, and at close quarters it was far less drab and notably more elegant than expected.Willet, Abaco Marls 4

It foraged slowly towards us, keeping a beady inky-black eye on usWillet, Abaco Marls 2

At one time it came within a very few feet of us, then decided it had come close enough. We watched it stepping delicately away on its semi-palmated feet. The shot isn’t clear enough to show the slight webbing between the toes. However, you can clearly see the barred tail.Willet, Abaco Marls 5

In the c19 and early c20 there was a sharp population decline of these fine birds due to hunting. I’m not sure if it was for feathers, food or fun. All three, probably. Their population has recovered and their IUCN status is currently ‘Least Concern’, but like so many similar species they remain at risk, especially through continued habitat loss.

The Willet call and song are very distinctive, and are reproduced here via the great bird-noise resource Xeno-Canto



Willet, Abaco Marls 6All images RH except header (Wikimedia) & in-flight image (Greg Page @ Cornell Lab for Ornithology)

(PS if you think the traditional RH puntastic title is laboured, be grateful I didn’t proceed with the initial idea of working ‘Bruce Willets’ into this post. It didn’t work, on any level…)




[I published the original of this post a year ago. I discovered that it had been put badly out of kilter by recent blog format change, so I have amended and to an extent updated it, with larger photos (NB the video was my first feeble foray).  So yes, it’s a retread, which I rarely do; but I wasn’t tooled up with Facebook & Twitter then, and thankfully a couple more people now read this thing, so it possibly deserves a fresh outing. No? Well I’m doing it, regardless]

It’s 7.15 and breakfast time at Delphi. At 8.00 the trucks, skiffs, guides and fishers will set off to the fishing grounds for the day, leaving you with an empty beach, shells, warm sea, the pool, the hammock and your book. For the moment, the talk is of the excellent ‘Full Abaco’ breakfast, the weather, ‘Delphi daddies’ & ‘crazy charlies’ and someone’s mislaid reel. Sandy enters to announce that there’s a place free on your partner’s skiff… and offers it to you. So what should you, a non-angler, expect of a day out on the flats?

THE SKIFFS These are top-of-the range boats, capable of considerable speed getting out to the fishing grounds. The ride can be bumpy, splashy and even chilly in the early morning, so bring a fleece and a waterproof top. Camera? Essential. Here is a Delphi skiff on a sand bar in Cherokee Sound, parked for lunch and some quality conch and sand-dollar hunting. So for a start, the day isn’t ALL about fishing…

THE FISHING GROUNDS You will leave from one of three launch points and speed across the water to the bonefishing areas. The main one is “Nettie’s”, with access via a narrow man-made channel to the Marls…

… more than two hundred square miles of mangrove swamp, islets, channels and fish. The journey to Nettie’s may seem quite a long way as you bump along through the pine forest on a network of logging tracks. Watch out for small birds flickering all around as you pass.



Launching a skiff at Nettie’s

Plans are hatchedGood to go…

Stowing gear in the front (forrard?) locker. There’s also one behind the seats for the lunch cool boxes. And the fuel…

The other two launch areas are Crossing Rocks (a short drive south of DCB) or Casuarina Point for Cherokee Sound (a slightly longer drive north of DCB)

The jetty at Crossing Rocks – skiffs being prepared

The launch point at Casuarina. A channel leads out to Cherokee Sound

Two boats in the channel – the authentic James Bond chase experience

WHAT’S THE POINT? Bonefishing! You’ve heard all the Club talk, you’ve seen your partner fussing over all those bits and pieces in your room: now see it in action. Once you get out to a fishing area, the guide cuts the engine… and suddenly you are being poled very slowly and almost noiselessly across the shallow flats

The guide stands on the platform at the back of the skiff, using the advantage of height to scan the shallow water; the fisher stands at the front looking tensely for grey shadows underwater, waiting for the magic words…

 “…hey, bonefish, 10 o’clock, 4 of them moving right, 30 feet… see them?” 

And it’s ‘game on’. This isn’t the place for a discourse about casting technique and style – I have neither (Sandy, of me: “Muppet”) – but I promise that you will get completely caught up in the excitement when a fish takes the fly and takes off towards the horizon, stripping the line and backing from the reel… (I realise the image above may suggest… well he’s just fishing, OK?)

THE QUARRY – grey ghosts below water, bars of silver above. Caught on the ‘fly’ which are in fact shrimp or crab imitations, with barbless hooks to make the chance of losing a fish that much greater… This ensures that a boated fish can be returned to the water as easily and quickly as possible. It’s all ‘catch and release’, though some (me) find that mostly the fish very sensibly self-release long before they ever reach the boat…

Abaco bonefish off Crossing Rocks (just caught and released)Guide Ishi with Abaco bonefish caught on the MarlsGuide Robin Albury removes the barbless hook before returning the fishgood specimen‘Ishi’s Fishy’, as he would say

All images, and indeed fish, ©RH

There is even the possibility that at some stage you may unexpectedly be handed a rod (even if you have never held one before, or wanted to) with ‘fish on’… Here, Robin has hooked a 2.5 lb fish and handed the rod to Mrs RH (then engrossed in eating a cheese roll) who successfully played and brought in her first ever fish…

PART 2 will deal with what else goes on during the day: the scenery, birdlife, sharks, turtles, blue holes and so forth. For now, here is a short clip of the skiff ride out to the Marls, to give you an idea. NB this was a very calm day – things can get a little bumpier and wetter at times. The seats are padded, but not very… 

 [Ultra-cautious music credit to Joe Satriani who sued Coldplay for alleged tune ‘borrowing’ saying “I felt like a dagger went right through my heart. It hurt so much”. Case dismissed + unspecified settlement…  Way to go, Joe! Want to check? Cut ‘n’ paste this: Then by way of counterbalance try John Lennon’s Imagine vs Coldplay’s ‘Fix you’ at (cut ‘n’ paste)]                

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