An Extraordinary Day…

I arrived on Denis early on the afternoon of Monday 24th and on leaving the airport area and heading towards the hotel I immediately became aware of a new and unusual bird call – a high-pitched staccato trill. Looking up I saw several bright green birds stunting and swooping in the air, Bee-eaters were flying everywhere! In truth this was not such a surprise as I had been contacted a few days before by Adrian Skerrett of the Seychelles Birds Record Committee (SBRC - see link in sidebar). Adrian had informed me that several islands in the archipelago had reported an influx of bee-eaters in the preceding days and wanted to know what the status on Denis was. What was surprising was the shear number of them. Every prominent perch on every tree and bush along the path seemed to hold one of these beautiful green creatures and the air in every clearing and break in the canopy was alive with the birds darting and swooping in pursuit of their insect prey. I stopped to watch a bird on its perch, every few seconds it swooped off hawking for an insect before veering round to return once more to its previous vantage point – such activity was repeated on practically every prominent branch along my route.

This in itself was remarkable enough but once at the hotel the resident manager Paul Horner advised me that there were some 50 or more falcons on the island as well!!! To be honest I was rather sceptical that there could possibly so many birds of prey on the island at one time and thought it likely there were maybe half-a-dozen or so birds of prey that in their circling might give the impression of being more numerous. I rapidly revised this opinion on walking down the runway, however, falcons were everywhere it was astonishing and they were equally abundant down the east coast in the area called Belle Etoile - I have never seen anything like it before and 50 birds appeared a fair estimate of their number.

The combination of these occurrences changed the whole ambience of the island and imbued a certain sense of awe to the whole scene. It reminded me of the feeling I used to get during my first year in Seychelles when every few days I would encounter something new, exotic and remarkable – it was an extraordinary day.

Species.

The bee-eater was of the blue-cheeked variety – Blue-cheeked bee-eater (Merops persicus) - which occurs from northern Egypt through the Middle East to Pakistan and India, and overwinters in Africa. It furthermore lived up to its name on Denis cleaning out the hives at the apiary and according to the hotel gardeners decimating the wasp population too!

Birds of Prey, like certain waders, due to the similarity of various species can be rather difficult to identify and this is certainly not my field of expertise – but the falcons were predominantly Amur Falcons (Falco amurensis) as the adult male has very distinctive plumage and once having seen that it made it easier to zero in on the plumage characteristics of the female. The Amur falcon breeds in northeast Asia and migrates to southeast Africa.
There was however at least one other species present with birds being noticeably larger _ I was unable to get a good look at these birds but Catherina and others also saw them and believe they may have been Eurasian hobbies (Falco subbuteo). As I said several species are quite similar and we will be sending photos to the SBRC to try and pin down identifications.

Numbers.

On an island like Denis, quite large and heavily forested, it is very hard to estimate how many land birds there may be. On Monday when I arrived however, the bee-eaters were the most abundant bird in the air in clearings and on walking around the island later, as part of my normal duties, they were also present in considerable numbers round the coast and in particular the east coast and my estimate would have been several hundred (i.e. 3-500 birds). On Tuesday the numbers were significantly reduced and yet that evening there were more than a hundred of the birds hawking over the runway alone! The decline continued over the next two days with a marked reduction each day but even so on my departure around midday on Thursday there must still have been between at least 50 bee-eaters on the island. Furthermore I am told by Catherina and other island residents that the first birds were noted on the afternoon of Wednesday 19th and that by the day of my arrival numbers had already significantly reduced from the peak of Saturday. Putting these observations together would suggest that there were at least 500 bee-eaters on the island over the weekend.

With regard to the Falcons I think 40-50 is a good estimate with the birds concentrated in and around the runway and also down the Belle Etoile (east) coast. I have never seen so many birds of prey together at one time and it was a truly amazing sight! On Tuesday morning Catherina and Paul Horner undertook a count along the runway and encountered 23 birds of prey in just one transect! Numbers declined noticeably from Tuesday to Thursday. The birds were best seen perched along and hunting over the runway. They could hover - almost harrier-like - when facing into the wind and would swoop down onto the runway to take insects and lizards – but also birds! I received several reports of the falcons taking bee-eaters and also a turtle dove. I latterly also saw for myself thanks to the help of an estate staff member a female falcon feeding on a bee-eater.
With regard to the larger bird of prey species, I think there were only 2 or 3 on the island.

News round-up

(Please note that this post was written Monday the 24th November but due to internet problems is only being posted now).

Sorry for the delay in posting but things have been pretty hectic lately, sadly mostly due to dull, ineffectual committee meetings which one has to attend just in case something important is raised – but of course it generally isn’t!!!

We should, however, have some exciting new developments on Denis in the coming days and I hope very much to be able to report back to you on Denis’ role in a new conservation first sometime next week… so keep checking back.

In the meantime let me just summarise matters from my visit to the island of November 14th-16th which I haven’t reported on yet:

• Fairy tern and Tropicbird progress:
  Fred and Tina are both progressing well and I have added the latest photos at the foot of the page. The first fairy tern juvenile appears to have finally left its perch which is good, whilst the second now appears adult except for the remnant brown barring on its wings. Only one of the other two tropicbird ground nests is currently occupied but does give the impression it may be incubating.
• Shearwater colony:
  All appears well at the shearwater colony with the egg I previously reported on still under incubation (see posts of November 7th and October 26th).
• SMR update:
  Great news that we have a new chick in Territory 1 and also that the juvenile under Catherina’s captive care appears well on the way to recovery which is most encouraging. The new pair that we hoped was forming in the southern portion of the island (see post of October 7th), however, appears to have failed. the female is no longer resident there and the male has been found wandering further afield no doubt in search of the female. The female has not been seen for a few days now but it is assumed that she has resumed floating – so I will keep you up updated on developments.
• Migratory birds:
  There has been a notable decline in the number of wading birds around the island recently but I did twice see the juvenile Purple heron during my last visit so that is still resident having first been seen on October 3rd (see post of October 5th).
  
  

Shells 1 – Trochus virgatus

In recent weeks I have been undertaking frequent circuits of the island to count turtle tracks. This has also given me the opportunity to note the various species of shells that are washed up at high tide. One of the projects under the island’s biodiversity plan is to survey the marine life on the surrounding reef flats and whilst that activity is not scheduled for another couple of years, identification of shells on the beach is as good a starting point as any.

Of course many of the shells washed up are old or damaged and not of sufficient quality for good photographs to be taken such that readers can readily identify the species in question from the photo on the blog. So in each case I will only post on a species when I encounter a good quality and characteristic shell specimen.

So I start today with Trochus virgatus. The Trochidae are a family of medium to large sea snails with conical shells that typically graze on algae though some eat sponges. T. virgatus is very similar to T. maculatus with one of the key differences being that the columella of maculatus is toothed. Jarrett (2000) states that T. virgatus is common in Seychelles being typically found in secure niches on the open reef.

Simply click on the photos below to enlarge.

(Photos J Nevill 2008).

Jarrett, A.G. (2000): Marine Shells of the Seychelles. Carole Green Publishing, Cambridge, UK. ISBN 1 903479 00 2

National television coverage for environmental work on Denis Island…

I was not able to undertake my usual routine during my latest visit to Denis – firstly I was rather unceremoniously bumped from the flight going up on Thursday due to the fact that the plane was overloaded!!! So after waiting for my luggage to be offloaded I had to then head back to the office, only to go back out to the airport the next day. Fortunately I was allowed on the Friday flight and hence was able to check on the Fairy tern and Tropicbird chicks we have been following that afternoon.

On Saturday however, there was a morning flight that brought in Ms. Srdjana Janosevic and Mr. Humbert Mellie from the Seychelles Broadcasting Corporation – the national television company. Srdjana had been made aware of this blog by Lena Desaubin (Director of Education, Information and Communications at the Department of Environment) and having read through it was interested to come and film some of the work we are doing on the island for a national TV spot and perhaps also for wider distribution.

So on Saturday morning and afternoon, we went round the island and Humbert took the opportunity to film our “famed” fairy tern and tropicbird chicks “Fred and Tina”, the shearwater colony, some good footage of Magpie robins, good close ups of an adult tropicbird, a sub-adult Brown noddy, Bridled terns etc… later that afternoon they interviewed hotel staff and took more scenic shots round the island.

We were up nice and early on Sunday morning to accompany Catherina on her morning round to provide the magpie robins with their first supplementary feed of the day. We started off at Catherina’s place to film her feeding the captive juvenile under her care and then we headed off. Humbert got some great footage of the robins coming to their feeding stations in three different territories meaning he and Srdjana should be spoilt for choice in the editing room. Catherina was also interviewed about her work and the robins. She then went and checked on a nest in Territory 1 and was able to confirm that the new chick there is progressing well.

We spent the rest of the morning trying to fill in a few gaps with footage of the giant tortoises, the large day gecko, the Seychelles warbler, more shots around the hotel and additional scenery etc…

Srdjana will let me know in due course when the footage will be aired on national TV and will also be posting footage on various internet sites – the links to which I will include on this blog in due course, to enable those who are interested to go and view it. There is also the intention to submit footage to an international carrier/network and likewise I will advise readers on that as and when I hear myself. So keep checking back for information!

Our sincere thanks go to Srdjana, Humbert, Lena and the SBC for showing interest in our work.

SMR update.

The Seychelles magpie robin is a ground feeding bird, its favoured method of foraging is turning leaf litter and eating the invertebrates concealed beneath, it will however also take young lizards and small fish dropped by seabirds etc… The birds on Denis have been habituated to supplementary feeding on bird tables with special food mix prepared by Catherina. They are also opportunistic however, and often when I encounter a bird on the island I will disturb the leaf litter with my feet over an area of a square metre or two and then move a few yards away. The bird, eyes-a-glitter, rapidly descends and having cocked a sidelong glance at you to make sure you are far enough away for its comfort begins to feast on the exposed invertebrates.

A logistical mishap late Tuesday afternoon left me without a room to change etc.. and whilst I waited at the old settlement north of the runway I saw one of the single males sitting on a branch in a Banyan tree. I kicked up some leaf litter and took the opportunity to take a few photos (see sidebar).

The next morning I went to check on the captive chick which I reported on in my post of November 3rd. As I approached the aviary on Catherina’s veranda the bird was giving repetitive rasping and plaintive call. So, having checked that it had water, I set about trying to find it some food by digging around in the adjacent undergrowth and turning logs etc… Over the next 30 minutes or so I was able to bring it quite a feast of small cockroaches which are amongst their favourite food. When I approached to proffer the food the chick, with its mouth gaping yellow, would begin begging louder and louder reaching a crescendo at the point when it would pluck the cockroach from between my fingers.

I did not take the bird out to examine it or take photos (because they would have necessitated a flash) as I did not want to unduly stress it, but it looked quite healthy and I will follow up with Catherina in due course as to the status of its wing.

Keeping checking back for updates!

Fairy Tern and Tropicbird Progress (5).

Fred is developing very well with significant growth again to be noted. I will rearrange previous photographs and add them to the bottom of the page so that the progress of Fred and Tina can be followed through time so scroll down for those dated images.

The second juvenile is also developing well with plumage near fully developed and the juvenile barring on its wings fading. The first juvenile however continues to give me cause for concern for although it now appears fully developed I have yet to see it fly from its perch.

The tropicbird adults are still at their nest sites but I have yet to verify whether they are indeed now incubating. Tina however shows considerable growth and has now largely lost her cute fluffy appearance with extensive plumage development now apparent. Again scroll down to the bottom of the page to see the development of Tina through time in dated photographs.

Bird Bulletin 9

During my most recent visit to Denis (4 – 6 November) I noted some interesting activity and changes in the island’s bird population:

• I checked on the shearwater colony and was this time able to get a much better photo of the adult shearwater incubating its egg (see sidebar and also my post of 26th October) and all seems well.
• There has been a significant decline over the last week in the number of wading birds on the island. I don’t know why this should be but the number of Whimbrels has dropped dramatically to just a handful and there has been a significant decline in the number of Turnstones. Likewise I noted only one Crab plover, a few Sand plovers, one Ringed plover, one Pratincole and I didn’t see a single Grey plover. This represents a very dramatic change and I can only suggest that it may be linked to the very calm and hot weather we have been experiencing lately.
• Furthermore Crested tern numbers have dropped from a record high of 14 over the last few weeks to just 2.
• The bridled tern roost also appears to have dispersed though individual birds are still to be seen perched on the mooring buoys during the day.
• I noted interesting behaviour amongst the fairy terns that I have not noticed before. It is usual to see fairy terns in pairs or threes in their swooping flight display particularly along the coastline and I have on several occasions in the past observed them in large numbers mobbing a migrant bird of prey. On Tuesday 2nd however I noted between 40 or 50 of them flying together very high up (several hundred feet), circling and tumbling, for about 10 minutes. There was no other bird amongst them – so this was not a mobbing event – something new for this observer.
• As an aside I also noted a sub-adult Brown noddy in the hotel garden. It is perched on a low ornamental palm and has clearly fallen out of its nest in a nearby coconut palm. The bird is well-developed with only slight traces of its juvenile plumage still visible, and it is being tended to by its parents so it should be fine. It does however offer an interesting start to the guest nature walks as they do not usually get such a good view of this species.
  

Nature Watch 3

Flying in on Tuesday 4th October Denis was picture perfect – there had a been some rain in the preceding week and the foliage showed a fresher green whilst the sea was as still and clear round the island as I have ever seen it. As we circled before final approach over the shoals to the northwest I looked down in the hope of seeing some wildlife in the water The water being so clear I had high expectations but on the approach I was disappointed to only see one turtle surfacing for a breather.

On arrival I made my usual check on the fairy tern juveniles that I have been following over the last couple of months and I will post on that later.

In recent weeks I have been undertaking thorough beach checks each time I visit in order to count turtle tracks (see post of October 22nd). It takes a good couple of hours to walk round the island and it is hard work with the sand very soft and fine in places and trees down blocking the way in others. It is also however a great opportunity to take in the beauty of the island and make various natural history observations.

Walking the beach on Thursday (6th) morning on the southwest beach I noted a turtle close in shore head above the water checking out the beach. It is normal for hawksbills to survey a beach before coming ashore, I assume to assess whether it is safe. The animal only being about 10 metres or so offshore, I hid behind a tree and kept still hoping it may soon emerge to nest. Whilst watching it cruise around in the shallow water my eye was caught by movement further offshore – there was a second animal about 40 metres out also surveying the beach. Over the next 5 minutes I realised there were at least 4 (and I believe 5) hawksbill turtles all within 50-60 metres of the shore all apparently assessing the beach as a suitable nesting site!!! I waited for some 20 minutes convinced that one would emerge at any moment but without luck. The need for me to finish my rounds in time to catch my plane off the island meant I had to move on but I am certain that 2 or more of these animals will have nested soon after.

One frequently encounters hermit crabs on the beach during a turtle track count and as per previous posts (see posts of July 16th and September 10th) recent GIF research has indicated that the populations on the island may be limited by a shortage of suitable shells for the crabs to grow into. Casual observations seem to support this as I encounter very large numbers of small crabs in neritas spp shells etc… but much fewer larger ones in turbo shells. Furthermore many of the larger hermits have clearly outgrown their shells. When a crab fits well into its shell its large chela (claw) and one leg should fill and close the shell aperture, effectively “closing the door” and protecting the animal from attack when it retreats within. I am however frequently finding specimens where several and even all the limbs remain exposed when the crab seeks refuge and this presumably makes the animal much more vulnerable to predation from species such as the crab plover.

Also during my rounds I have been paying closer attention to the old shells washed up at high tide and I have been photographing specimens which are still in reasonable condition to enable species identification and I hope to start making occasional posts on this in the coming weeks.

Check back regularly for further observations, news and updates!

SMR News 5: “Trials and tribulations…”

Well it seems hard times abound and not just for financial institutions, IMF indebted countries and Joe the plumber!! Not all goes smoothly for the Seychelles magpie robin in paradise either. Well I suppose if it was easy they wouldn’t be endangered…

So in the tried and tested formula, I’ll start with the good news and let it deteriorate from there…

• The fledgling from T3 is well and prospering and continues to harass its parents for food.


• The pullus from territory 4 (that I reported on as egg in Bird Bulletin 7) fledged on the 13th of October – yes it was a little further advanced than we had appreciated!


• On the 24th of October Catherina also observed the female of territory 1 entering a natural cavity in a Casuarina tree suggesting that breeding activity has recommenced there.

SMR TERRITORY MAP AS OF END OF OCTOBER 2008

CLICK ON THIS IMAGE TO ENLARGE.

On the 14th of October however Catherina noted that the new fledgling from T4 was having some difficulties. She captured it to examine it and found that the skin on one wing appeared old and shrivelled and that the feathers there were falling out and breaking (see photos in sidebar). The area was also attracting flies and as we all know there is no fooling them! So Catherina took the bird into captivity and treated the skin with terramycin spray whilst seeking advice from veterinary specialists overseas – via Rachel Bristol of Nature Seychelles.

The primary concern initially of course was that the longer the bird was away from its parents the more likely they would reject it when it was returned. To counter this Catherina returned it frequently, in a small carrying aviary to its territory so that the parents could see and interact with their offspring. Feedback from the vets however ultimately resulted in the recommendation that the bird should be kept in captivity and hand reared. So Catherina has set up a small aviary on her veranda to facilitate the hourly feeding her new dependent requires. To date the bird appears otherwise healthy, but this development is less than encouraging. Of the 4 chicks the island has produced so far the first was lost to a likely Myna bird attack whilst still a nestling, the third appeared to have a physical deformity of its legs and died within a couple of days of fledging and now this the fourth is manifesting other problems. The second fledgling continues to prosper.

Of course, as I have previously stated, juvenile mortality in SMRs is known to be high and it is for that reason we do not count a bird as part of the population until it has reached full independence. Nevertheless it is to be hoped that average success will ultimately exceed 1 in 4 particularly at this crucial formative stage of the new colony where a rapid increase in numbers is so desirable for the future resilience of the population.
Keep checking back for news on our captive chick and the population in general.