Catherina, I and others are keeping our eyes peeled for migratory birds and so building on my first report (posted on October 5th) and in addition to the normal large numbers of whimbrel and turnstone, we have the following to report.
Ringed Plover (Charadrius hiaticula): a single bird seen in the hotel gardens, and on the east coast reef flats.
Grey Plover (Pluvialis squatarola): total numbers of wading birds of any particular species round the island are very difficult to estimate as the birds are often dispersed around the coast and are of course much more mobile than your average observer. It is clear however we have several grey plovers (5-6) on the island at this time.
Crab Plover (Dromas ardeola): there are at least 2 and possibly as many as 4 of these elegant birds on the island being most commonly seen around Pointe l’Est
Gull-billed tern (Gelochelidon nilotica): During the 9th and 10th of October I observed 1 bird on three separate occasions flying quite low over the coast, twice around Pte Mme Guichard and once on the west coast by the runway.
Catherina has two interesting records of a European turtle dove (Streptopelia picturata) on the 5th of October and a Common pratincole (Glareola pratincola) on the 6th.
Finally Mr Mickey Mason, an island resident, spotted mid-month an unusual visitor along the coast and was able to take some photos from a distance (see sidebar), as per his own description:
“I found a tern last weekend flying over the beach and diving for food amongst weed and debris. It has graceful flight but quite agile, turns sharply to dive and hover above the beach when it has noticed something of interest. Looks like a type of Marsh tern[1]… sorry about the photo quality.”
This information and the photos of the bird have been forwarded to Mr. Adrian Skerrett of the Seychelles Bird Record Committee (see link in sidebar) in the hope that it may be possible to make a verified identification.
[1] (a) Chlidonias hybridus: whiskered or marsh tern; (b) Chlidonias leucopterus: white-winged or marsh tern
Friday, October 31, 2008
Tuesday, October 28, 2008
Fairy Tern and Tropicbird Progress (4).
As usual the first thing I checked on arrival on Thursday 23rd was the status of the three fairy tern juveniles that I have been following over the preceding weeks and reporting on in the earlier editions of this post.
• As with two weeks ago the first juvenile looks fully developed except for the lack of the purple colouration at the base of its bill. I am becoming a little concerned however that this bird is always on its perch. I have yet to see it fly and does seem rather passive. Those of you that have followed the earlier posts on this topic will recall that I started these observations because an unusually high number of fairy tern chicks seemed to be dying around the island in the preceding months suggesting perhaps that there was a food shortage. I do hope that this bird is not following that route.
• The second chick that we have followed since hatchling is progressing well. As reported 2 weeks ago it is alert and already flying. Its plumage has further developed in the interim and the juvenile barring on the wings is becoming less prominent.
• Our third chick “Fred” which we have been following since it was an egg(!) is also showing good growth and development, “he” is very alert and has taken to moving up and down his branch. The plumage however is still very much that of a chick.
Moving on to the Tropicbirds I have very encouraging news:
• The first nest site that had been unoccupied during my checks over the last four weeks again has an adult in place – so let’s hope for an egg this time!
• The adult is still present at the second site and I have still been unable to determine if there is an egg being incubated – the single large brick-red egg typically takes some 6 weeks to hatch and is incubated in turn by both parents.
• Tina our chick appears very well, she is alert appears in good condition and has grown significantly such that the first proper juvenile plumage with black barring is now evident (see photo in sidebar).
Check back regularly for further updates on Fred and Tina’s progress.
• As with two weeks ago the first juvenile looks fully developed except for the lack of the purple colouration at the base of its bill. I am becoming a little concerned however that this bird is always on its perch. I have yet to see it fly and does seem rather passive. Those of you that have followed the earlier posts on this topic will recall that I started these observations because an unusually high number of fairy tern chicks seemed to be dying around the island in the preceding months suggesting perhaps that there was a food shortage. I do hope that this bird is not following that route.
• The second chick that we have followed since hatchling is progressing well. As reported 2 weeks ago it is alert and already flying. Its plumage has further developed in the interim and the juvenile barring on the wings is becoming less prominent.
• Our third chick “Fred” which we have been following since it was an egg(!) is also showing good growth and development, “he” is very alert and has taken to moving up and down his branch. The plumage however is still very much that of a chick.
Moving on to the Tropicbirds I have very encouraging news:
• The first nest site that had been unoccupied during my checks over the last four weeks again has an adult in place – so let’s hope for an egg this time!
• The adult is still present at the second site and I have still been unable to determine if there is an egg being incubated – the single large brick-red egg typically takes some 6 weeks to hatch and is incubated in turn by both parents.
• Tina our chick appears very well, she is alert appears in good condition and has grown significantly such that the first proper juvenile plumage with black barring is now evident (see photo in sidebar).
Check back regularly for further updates on Fred and Tina’s progress.
Sunday, October 26, 2008
Shear(water) Delight – Another first for Denis Island!!!
In previous posts (see August 18th and October 19th) I have written of the re-establishment of a small Wedge-tailed shearwater (Puffinus pacificus) colony on Denis and the significance this has as an indicator of the rehabilitation of the island’s ecosystem since the rat eradication of 2002. As of November 2007, a small colony of burrows was found on the east coast of the island but at that time I was unable to find proof of breeding activity. The shearwater may breed at any time but shows a distinct peak in breeding activity September through February. I have, therefore, been monitoring the burrows closely over the last 4-6 weeks in the hope of finding evidence of breeding and thereby prove the species is indeed once again established on Denis.
So I am very happy to relate that on Thursday 23rd October I found, and was able to photograph (see photos in sidebar), an adult shearwater incubating an egg in one of the burrows!!! This therefore now verifiably proves that the species has established a small breeding colony on the island – yet another exciting landmark for Denis.
Skerrett et al (2001) state of wedge-tailed shearwaters that:
“Sexes share incubation, each shift lasting several days. Incubation usually takes 50-54… and chicks fledge after three months.”
I will continue to keep a close eye on our small colony in the coming weeks and hopefully in due course I will be able to find more eggs and record the subsequent chicks. So keep checking back for updates!
It doesn’t stop there however, Mr Paul Horner the hotel manager, has advised me that in recent days he has twice had call to remove from the hotel restaurant what, as per his description, sounds very much like an Audubon’s shearwater (Puffinus lherminieri); the bird having become confused by the restaurant lights. I have asked him to photograph the bird should the incident reoccur as if it can be confirmed as an Audubon’s this would suggest that this species may also now be roosting on the island!!!
Skerrett et al (2001): Birds of Seychelles. Christopher Helm (publishers) Ltd. London.
So I am very happy to relate that on Thursday 23rd October I found, and was able to photograph (see photos in sidebar), an adult shearwater incubating an egg in one of the burrows!!! This therefore now verifiably proves that the species has established a small breeding colony on the island – yet another exciting landmark for Denis.
Skerrett et al (2001) state of wedge-tailed shearwaters that:
“Sexes share incubation, each shift lasting several days. Incubation usually takes 50-54… and chicks fledge after three months.”
I will continue to keep a close eye on our small colony in the coming weeks and hopefully in due course I will be able to find more eggs and record the subsequent chicks. So keep checking back for updates!
It doesn’t stop there however, Mr Paul Horner the hotel manager, has advised me that in recent days he has twice had call to remove from the hotel restaurant what, as per his description, sounds very much like an Audubon’s shearwater (Puffinus lherminieri); the bird having become confused by the restaurant lights. I have asked him to photograph the bird should the incident reoccur as if it can be confirmed as an Audubon’s this would suggest that this species may also now be roosting on the island!!!
Skerrett et al (2001): Birds of Seychelles. Christopher Helm (publishers) Ltd. London.
Wednesday, October 22, 2008
The Hawksbill Turtle Season Begins…
When Denis De Trobriand discovered Denis in 1773 he described turtles as abundant in the waters around the island. Two species of turtle are still to be found nesting on Denis today – if in much reduced numbers from the abundant days of De Trobriand.
The Green turtle (Chelonia mydas) nests on Denis in small numbers year round with a peak of activity in April through June. The Hawksbill turtle (Eretmochelys imbricata) has a much more distinct nesting season (October – February) which is now commencing on Denis.
The hawksbill is classified as critically endangered by the World Conservation Union and Seychelles is one of the best five remaining locations in the world for the species (Meylan & Donnelly 1999).
Threatened by hunting for its shell (known as tortoiseshell) and loss of habitat – most critically nesting habitat – the hawksbill has received full protection under the law in Seychelles since 1994. Despite the success of certain protected area nesting sites the overall population has continued to decline (Mortimer 2004) with loss of nesting habitat to tourism development and activity being considered the primary ongoing problem.
Denis Island is member of the “Turtle Action Group Seychelles” (TAGS) which is a newly-formed association of some 14 agencies that manage turtle rookeries (nesting areas). As a requirement of its membership Denis must collect information on its nesting turtle populations and submit it to a national stakeholder database operated by TAGS. Data has been collected in the past on nesting turtles but limited human capacity has and continues to be the primary constraint to the consistent collection of standardised data. During the peak of the season thorough monitoring on Denis would entail at least two people working full-time. It is hoped that for season commencing in 2009 that designated accommodation will be available on the island to enable basic but thorough data collection to be undertaken by volunteers.
In the meantime however efforts will be made to gather the most basic form of data through the counting of tracks on the beach. Although turtles by no means nest successfully every time they come ashore the body of work by Dr Jeanne Mortimer has enabled a ratio of beachings per nest to be established for the Seychelles hawksbill population and this can be used to estimate the number of females actually nesting on Denis.
I will in due course periodically report on the progress of the season and set this in the context of management measures. This information will help guide management activity on the island and identify issues to be mitigated in order to optimise the breeding success of the hawksbill rookery on Denis. So check back regularly for news on the season as it progresses!
Meylan, A.B. & Donnelly, M. (1999). Status and justification for listing the hawksbill turtle (Eretmochelys imbricata) as Critically Endanagered on the 1996 IUCN Red List of Threatened animals. Chelonian Conserbvation and Biology 3 (2): 200 – 224.
Mortimer, J.A. 2004. Seychelles Marine Ecosystem Management Project (SEYMEMP): Turtle Component. Final Report. Vol 1: Text, 243 pages. Vol 2: Appendix 1-11, 158 pages.
The Green turtle (Chelonia mydas) nests on Denis in small numbers year round with a peak of activity in April through June. The Hawksbill turtle (Eretmochelys imbricata) has a much more distinct nesting season (October – February) which is now commencing on Denis.
The hawksbill is classified as critically endangered by the World Conservation Union and Seychelles is one of the best five remaining locations in the world for the species (Meylan & Donnelly 1999).
Threatened by hunting for its shell (known as tortoiseshell) and loss of habitat – most critically nesting habitat – the hawksbill has received full protection under the law in Seychelles since 1994. Despite the success of certain protected area nesting sites the overall population has continued to decline (Mortimer 2004) with loss of nesting habitat to tourism development and activity being considered the primary ongoing problem.
Denis Island is member of the “Turtle Action Group Seychelles” (TAGS) which is a newly-formed association of some 14 agencies that manage turtle rookeries (nesting areas). As a requirement of its membership Denis must collect information on its nesting turtle populations and submit it to a national stakeholder database operated by TAGS. Data has been collected in the past on nesting turtles but limited human capacity has and continues to be the primary constraint to the consistent collection of standardised data. During the peak of the season thorough monitoring on Denis would entail at least two people working full-time. It is hoped that for season commencing in 2009 that designated accommodation will be available on the island to enable basic but thorough data collection to be undertaken by volunteers.
In the meantime however efforts will be made to gather the most basic form of data through the counting of tracks on the beach. Although turtles by no means nest successfully every time they come ashore the body of work by Dr Jeanne Mortimer has enabled a ratio of beachings per nest to be established for the Seychelles hawksbill population and this can be used to estimate the number of females actually nesting on Denis.
I will in due course periodically report on the progress of the season and set this in the context of management measures. This information will help guide management activity on the island and identify issues to be mitigated in order to optimise the breeding success of the hawksbill rookery on Denis. So check back regularly for news on the season as it progresses!
Meylan, A.B. & Donnelly, M. (1999). Status and justification for listing the hawksbill turtle (Eretmochelys imbricata) as Critically Endanagered on the 1996 IUCN Red List of Threatened animals. Chelonian Conserbvation and Biology 3 (2): 200 – 224.
Mortimer, J.A. 2004. Seychelles Marine Ecosystem Management Project (SEYMEMP): Turtle Component. Final Report. Vol 1: Text, 243 pages. Vol 2: Appendix 1-11, 158 pages.
Sunday, October 19, 2008
Denis Island turns the corner…
This blog is one means of publicising the work Denis Island Development (Pty) Limited and GIF are undertaking, on Denis Island. The web is not available to all however and as such we also utilise other media to raise awareness and share information with stakeholders, interested parties and the general public. The article below is published in today’s (October 20th) Seychelles Nation newspaper. I have also posted a photo of the article below – click on this photo to see the article and its images in full size.
Denis Island turns the corner…
Denis Island began its ecosystem restoration programme 10 years ago when it undertook a preliminary alien mammal species assessment. Cats were subsequently eradicated in 2000 and rats in 2002. This is very important as Seychelles naturally has no terrestrial mammals, except for two species of bat, and the fauna and flora of the islands have evolved therefore without the necessary adaptations to cope with the impacts of animals such as rats, cats, pigs and goats. Today Denis represents 17.5% of the rat-free land in the central archipelago and is thus vital to several national conservation initiatives.
Denis Island has embraced stakeholder partnership as a means of furthering its own and national environmental objectives. In 1999-2001 Denis worked with Nature Seychelles to rehabilitate 35 hectares of broadleaved woodland habitat on the island in order to enable the introduction of rare endemic birds. In 2004 the rare Seychelles fody and Seychelles warbler were introduced and monitoring over subsequent years has shown that the populations have established well and are expanding. Then in June of this year, again in partnership with Nature Seychelles, 20 endangered Magpie robins were introduced and here too progress is very encouraging with island’s first fledgling developing well.
In 2006 Denis signed an agreement with the Green Islands Foundation (GIF), a local NGO, to develop an environmental management plan and provide technical support for its environmental initiatives. Since that time GIF has initiated various programmes on Denis, developed the island’s ecotourism product and established various databases. The monitoring undertaken has come at a crucial time and has recorded some major landmarks in the natural recovery of the island’s ecosystem post the 2002 rat eradication.
Over the last year Frigate birds have established a regular roost on the island with up to 50 birds being recorded; and a relatively large roost (200 – 300) of Bridled terns has also started to utilise the island out of breeding season.
Ground nesting seabirds are particularly vulnerable to rats and cats and so seabird occurrence has been monitored closely. In November of 2007 there was a most encouraging discovery of a small colony of wedge-tailed shearwaters. This bird excavates burrows underground in which to roost and breed. The new colony consists of only 20 or so burrows but has expanded over the last year and represents a major breakthrough in the recovery of the island’s ecosystem.Over the last 3 years a few pairs of white-tailed tropicbird have been noted to breed on the island in some tree cavities and also one high up in the lighthouse! What was really awaited however, was the first occurrence of ground nesting. Then last month, having seen none over the preceding 3 years, 3 adults were found nesting on the ground within 24 hours and the island now has its first tropicbird chick in a ground nest!!
These discoveries are fantastic news as they really show that the island has turned a corner in its recovery such that wild species like the shearwater and tropicbird are once again finding it suitable to establish colonies.
These developments are the fruit of 10 years of work and investment by Denis Island and show that man can work to restore island ecosystems and furthermore do so within the context of tourism and landscape production activities. This progress demonstrates that development and conservation can be undertaken side-by-side and indeed in the case of Denis can be considered interdependent. After all it is the revenue from the tourism development and landscape production activities that subsidises the rehabilitation and conservation programmes. Now these programmes have in turn resulted in a healthy and more productive ecosystem and an enriched ecotourism product for the resort.
Denis Island turns the corner…
Denis Island began its ecosystem restoration programme 10 years ago when it undertook a preliminary alien mammal species assessment. Cats were subsequently eradicated in 2000 and rats in 2002. This is very important as Seychelles naturally has no terrestrial mammals, except for two species of bat, and the fauna and flora of the islands have evolved therefore without the necessary adaptations to cope with the impacts of animals such as rats, cats, pigs and goats. Today Denis represents 17.5% of the rat-free land in the central archipelago and is thus vital to several national conservation initiatives.
Denis Island has embraced stakeholder partnership as a means of furthering its own and national environmental objectives. In 1999-2001 Denis worked with Nature Seychelles to rehabilitate 35 hectares of broadleaved woodland habitat on the island in order to enable the introduction of rare endemic birds. In 2004 the rare Seychelles fody and Seychelles warbler were introduced and monitoring over subsequent years has shown that the populations have established well and are expanding. Then in June of this year, again in partnership with Nature Seychelles, 20 endangered Magpie robins were introduced and here too progress is very encouraging with island’s first fledgling developing well.
In 2006 Denis signed an agreement with the Green Islands Foundation (GIF), a local NGO, to develop an environmental management plan and provide technical support for its environmental initiatives. Since that time GIF has initiated various programmes on Denis, developed the island’s ecotourism product and established various databases. The monitoring undertaken has come at a crucial time and has recorded some major landmarks in the natural recovery of the island’s ecosystem post the 2002 rat eradication.
Over the last year Frigate birds have established a regular roost on the island with up to 50 birds being recorded; and a relatively large roost (200 – 300) of Bridled terns has also started to utilise the island out of breeding season.
Ground nesting seabirds are particularly vulnerable to rats and cats and so seabird occurrence has been monitored closely. In November of 2007 there was a most encouraging discovery of a small colony of wedge-tailed shearwaters. This bird excavates burrows underground in which to roost and breed. The new colony consists of only 20 or so burrows but has expanded over the last year and represents a major breakthrough in the recovery of the island’s ecosystem.Over the last 3 years a few pairs of white-tailed tropicbird have been noted to breed on the island in some tree cavities and also one high up in the lighthouse! What was really awaited however, was the first occurrence of ground nesting. Then last month, having seen none over the preceding 3 years, 3 adults were found nesting on the ground within 24 hours and the island now has its first tropicbird chick in a ground nest!!
These discoveries are fantastic news as they really show that the island has turned a corner in its recovery such that wild species like the shearwater and tropicbird are once again finding it suitable to establish colonies.
These developments are the fruit of 10 years of work and investment by Denis Island and show that man can work to restore island ecosystems and furthermore do so within the context of tourism and landscape production activities. This progress demonstrates that development and conservation can be undertaken side-by-side and indeed in the case of Denis can be considered interdependent. After all it is the revenue from the tourism development and landscape production activities that subsidises the rehabilitation and conservation programmes. Now these programmes have in turn resulted in a healthy and more productive ecosystem and an enriched ecotourism product for the resort.
Thursday, October 16, 2008
Tori’s View.
I have received word from our volunteers Tori Yates and Vicki Wheeler who have graduated from their course with distinction so congratulations to them both!!! Tori has been kind enough to write a post about her time on the island which I attach below.
From May to July 2008 my colleague, Vicki wheeler, and I worked on Denis Island as Volunteers for the Green Islands Foundation. Sitting now in my flat in Reading, UK; Denis seems a million miles away! Vicki and I worked on two projects on the island:
· a project to re-establish a sooty tern colony, and
· a project to investigate the hermit crab populations on the island their status and habitat associations.
These projects contributed to our MSc studies on Wildlife Management and Conservation at the University of Reading.
We arrived on Denis at the end of May with Professor Chris Feare, a leading expert on the Sooty tern with a long working experience of the species in Seychelles, to set up the sooty tern project.
To try to lure the birds we used a mixture of 3D, 2D models and loud speakers that played the colony noise of Sooty Terns. Similar projects had been undertaken in the past in North America on Least Terns and Arctic Terns but it had never been tried with Sooty Terns before. The experimental site was set up on the south of the island in an area of cleared coconut trees as Sooty Terns nest on the ground. During the two months we were on the island a total of 24 birds landed in the experimental site and exhibited a 95.7% preference for a specific combination of models and vegetation type. These highly significant findings on preference will allow a much more targeted management of the area during the second season of the project. The impact of broadcasting colony noise was vital as 100% of circling behaviour and bird landings occurred when the speakers were playing the colony noise. At the end of the nesting season the site was rearranged into a tighter knit colony using half of the available space. 30 of the models were painted with juvenile markings and these were interspersed with the adult models. This was to make the site look appealing to overflying or “prospecting” birds looking for a nesting site for the next year. (Ed: I was supposed to follow up on this the next month but unfortunately broke my arm and was unable to undertake the work. Occasional observations by others, however, suggest that this reformulation was very successful in attracting groups of birds to the area – see posts of 13th October and 21st September). The Sooty Tern colony experiment will run in 2009 and I am very hopeful that next year more birds will come to the site and a colony will be established.
While we were on the island Vicki and I also undertook a study of the hermit crab populations, so if you visit Denis and see crabs with numbers on their shells, this is not a strange phenomenon, but rather us giving each crab we found a unique number. Little was known about the hermit crabs on the island, and while we were there we found there are three species and they all prefer the native coastal vegetation. Vicki and I had a fabulous time on the island and we were really happy to have helped the GIF and the owners of the island find out more about the wildlife they have on Denis. While we were on the island, Vicki and I worked really hard, going out and sampling crabs or monitoring the Sooty Tern site everyday but we greatly enjoyed the experience and I know that we would both like to return to the island in the next couple of years when hopefully there will be a thriving Sooty Tern colony! We would like to thank in particular Mr and Mrs Mason for their hospitality by allowing us to live and work on their island, and also John Nevill for all the assistance he gave us while we were on Denis.
From May to July 2008 my colleague, Vicki wheeler, and I worked on Denis Island as Volunteers for the Green Islands Foundation. Sitting now in my flat in Reading, UK; Denis seems a million miles away! Vicki and I worked on two projects on the island:
· a project to re-establish a sooty tern colony, and
· a project to investigate the hermit crab populations on the island their status and habitat associations.
These projects contributed to our MSc studies on Wildlife Management and Conservation at the University of Reading.
We arrived on Denis at the end of May with Professor Chris Feare, a leading expert on the Sooty tern with a long working experience of the species in Seychelles, to set up the sooty tern project.
To try to lure the birds we used a mixture of 3D, 2D models and loud speakers that played the colony noise of Sooty Terns. Similar projects had been undertaken in the past in North America on Least Terns and Arctic Terns but it had never been tried with Sooty Terns before. The experimental site was set up on the south of the island in an area of cleared coconut trees as Sooty Terns nest on the ground. During the two months we were on the island a total of 24 birds landed in the experimental site and exhibited a 95.7% preference for a specific combination of models and vegetation type. These highly significant findings on preference will allow a much more targeted management of the area during the second season of the project. The impact of broadcasting colony noise was vital as 100% of circling behaviour and bird landings occurred when the speakers were playing the colony noise. At the end of the nesting season the site was rearranged into a tighter knit colony using half of the available space. 30 of the models were painted with juvenile markings and these were interspersed with the adult models. This was to make the site look appealing to overflying or “prospecting” birds looking for a nesting site for the next year. (Ed: I was supposed to follow up on this the next month but unfortunately broke my arm and was unable to undertake the work. Occasional observations by others, however, suggest that this reformulation was very successful in attracting groups of birds to the area – see posts of 13th October and 21st September). The Sooty Tern colony experiment will run in 2009 and I am very hopeful that next year more birds will come to the site and a colony will be established.
While we were on the island Vicki and I also undertook a study of the hermit crab populations, so if you visit Denis and see crabs with numbers on their shells, this is not a strange phenomenon, but rather us giving each crab we found a unique number. Little was known about the hermit crabs on the island, and while we were there we found there are three species and they all prefer the native coastal vegetation. Vicki and I had a fabulous time on the island and we were really happy to have helped the GIF and the owners of the island find out more about the wildlife they have on Denis. While we were on the island, Vicki and I worked really hard, going out and sampling crabs or monitoring the Sooty Tern site everyday but we greatly enjoyed the experience and I know that we would both like to return to the island in the next couple of years when hopefully there will be a thriving Sooty Tern colony! We would like to thank in particular Mr and Mrs Mason for their hospitality by allowing us to live and work on their island, and also John Nevill for all the assistance he gave us while we were on Denis.
Wednesday, October 15, 2008
Bird Bulletin 8
Crested Terns. These beautiful birds are still with us and indeed I recorded my highest count for Denis yet, on Friday 10th October, with 14 birds perched on the southern rocks.
Bridled (re)Terns. Having recorded a bridled tern roost of 200 – 300 birds on the island October through December last year, I have been on the look out at the southern point of the island where the bulk aggregated last year but without success. Then on Saturday 11th I was undertaking the first beach check of the new hawksbill turtle season when I noticed all five buoys off the west of the island were being used as perches by bridled terns. This gave an inclination that birds might be returning and sure enough further down the coast in the branches of a prominent casuarina tree I counted 15 bridled terns and 10 lesser noddies. The southern point of the island however still shows no sign of bridled terns and so I will keep monitoring this small roost area to see if it expands as the weeks pass.
Frigate birds. I have still to go and check properly on our Frigate bird roost as the right time usually clashes with other commitments but on the evening of Friday 10th I saw 29 Frigates flying very low over the island towards their southwest coast roost area.
Blue pigeons. I have written at length on the blue pigeons on the island in other posts (most notably the August 10th post entitled “Natural Recolonisation 1”) and the population continues to do very well. On Saturday 11th I saw two fledglings together accompanied by an adult in a small Morinda tree. The various ornithological reference works do state that the birds will occasionally have a clutch of two eggs, though I have personally never seen this, but this sighting seems to suggest the successful fledging of a clutch of 2 on Denis.
King Myna. The Myna birds on Denis have taken to imitating the call of the Magpie robins already causing me stop more frequently to verify whether I am indeed hearing a robin or not. I have also seen on 3 or 4 occasions recently, at Belle Etoile, what is known as a “King Myna” – i.e. a Myna bird which has no feathers on its head or neck thus revealing the yellow skin all over its head to quite startling effect.
Bridled (re)Terns. Having recorded a bridled tern roost of 200 – 300 birds on the island October through December last year, I have been on the look out at the southern point of the island where the bulk aggregated last year but without success. Then on Saturday 11th I was undertaking the first beach check of the new hawksbill turtle season when I noticed all five buoys off the west of the island were being used as perches by bridled terns. This gave an inclination that birds might be returning and sure enough further down the coast in the branches of a prominent casuarina tree I counted 15 bridled terns and 10 lesser noddies. The southern point of the island however still shows no sign of bridled terns and so I will keep monitoring this small roost area to see if it expands as the weeks pass.
Frigate birds. I have still to go and check properly on our Frigate bird roost as the right time usually clashes with other commitments but on the evening of Friday 10th I saw 29 Frigates flying very low over the island towards their southwest coast roost area.
Blue pigeons. I have written at length on the blue pigeons on the island in other posts (most notably the August 10th post entitled “Natural Recolonisation 1”) and the population continues to do very well. On Saturday 11th I saw two fledglings together accompanied by an adult in a small Morinda tree. The various ornithological reference works do state that the birds will occasionally have a clutch of two eggs, though I have personally never seen this, but this sighting seems to suggest the successful fledging of a clutch of 2 on Denis.
King Myna. The Myna birds on Denis have taken to imitating the call of the Magpie robins already causing me stop more frequently to verify whether I am indeed hearing a robin or not. I have also seen on 3 or 4 occasions recently, at Belle Etoile, what is known as a “King Myna” – i.e. a Myna bird which has no feathers on its head or neck thus revealing the yellow skin all over its head to quite startling effect.
Monday, October 13, 2008
Fairy Tern and Tropicbird Progress (3).
So back to our breeding seabirds for an update. Firstly the Fairy terns:
the first juvenile looks well and fully-fledged with only the lack of the purple band at the base of its bill to distinguish it now from an adult.
the second juvenile took me by surprise by flying off as I approached! It circled for a while and then returned but I kept my distance so as not to disturb it again. The bird still has clear juvenile barring on its wings and has not developed yet its full tail plumage but is clearly developing well.
Finally our egg has hatched and we have new young chick on the branch I have opted to name this bird “Fred” and will keep you informed of his/her development.
As for the tropicbirds:
· It does appear that the first nesting site has been abandoned.
· The adult is still at the second site and appears to be incubating.
· Our chick, to be known hence forth as “Tina”, has attracted a great deal of attention and feedback following my posting of its picture on the blog. Tina appears to be doing well with evident of growth over the last week.
Because of the relatively low number of breeding pairs of Tropicbirds on Denis I have decided to map the known breeding sites and will seek feedback from island staff to make it as comprehensive as possible before posting at a future date.
the first juvenile looks well and fully-fledged with only the lack of the purple band at the base of its bill to distinguish it now from an adult.
the second juvenile took me by surprise by flying off as I approached! It circled for a while and then returned but I kept my distance so as not to disturb it again. The bird still has clear juvenile barring on its wings and has not developed yet its full tail plumage but is clearly developing well.
Finally our egg has hatched and we have new young chick on the branch I have opted to name this bird “Fred” and will keep you informed of his/her development.
As for the tropicbirds:
· It does appear that the first nesting site has been abandoned.
· The adult is still at the second site and appears to be incubating.
· Our chick, to be known hence forth as “Tina”, has attracted a great deal of attention and feedback following my posting of its picture on the blog. Tina appears to be doing well with evident of growth over the last week.
Because of the relatively low number of breeding pairs of Tropicbirds on Denis I have decided to map the known breeding sites and will seek feedback from island staff to make it as comprehensive as possible before posting at a future date.
Sooty Tern Summary 2008 (Part 2).
This post follows on from my post of 21st September.
Once the area had been selected the next issue was to identify an appropriate form and source of models. As part of the scientific basis of the project we wanted to offer the birds a variety of stimuli in various combinations so as to properly assess their preferences. We investigated various options and ultimately went for 3 types:
· Moulds were made in the UK to enable the production of fibreglass models in Seychelles.
· 2-dimensional models were made out of plywood and painted
· Plastic models of crows were bought in UK and repainted and tails added to resemble sooty terns.
Unfortunately for some technical reason, that frankly still escapes me, the moulds and particularly their rubber interiors were not suitable for the local production of fibreglass models. So we were left with two types.
The sound system used to broadcast colony noise was purchased from a company that makes sound systems to scare pest species off crops in Europe. This was modified to play the noise of a sooty tern colony.
These different options plus control plots were combined with variations in vegetation management to generate 8 different stimuli combinations each repeated twice over the project area.
Vicki Wheeler and Tori Yates arrived at the end of May and set out the project with Chris Feare and the help of the Island Manager Camille Hoareau.
Observations were taken at set times (day and night) from a viewing platform constructed at one side of the project area. The interaction of Sooties with the trial area was recorded in terms of time spent overflying the area, height of flight and of course landings within the area. Tori and Vicki were equipped with night vision glasses to assist their nocturnal data collection.
Without going into specifics (because there are papers to be written and much more work to follow over the next 2 to 3 seasons), the area was successful in engendering interest amongst overflying sooty terns including numerous landings and demonstrating a clear preference for certain parameters.
At the end of the season models were re-positioned to reflect the favoured formulation and some 30 were re-painted as juveniles to give the impression of a successful small colony. I was supposed to follow up on this closely for another month but unfortunately broke my arm at that time and didn’t visit the island for a period of 5 weeks. However, occasional sightings by at least three individuals confirmed that the new formulation was particularly successful with 5 -10 birds seen to land at a time and numerous birds circling low overhead.
So with the results of the first season now gathered, it is for us to refine our approach accordingly for next season and hopefully optimise the scope for the establishment of a small breeding colony. It was certainly a most encouraging first year!
Once the area had been selected the next issue was to identify an appropriate form and source of models. As part of the scientific basis of the project we wanted to offer the birds a variety of stimuli in various combinations so as to properly assess their preferences. We investigated various options and ultimately went for 3 types:
· Moulds were made in the UK to enable the production of fibreglass models in Seychelles.
· 2-dimensional models were made out of plywood and painted
· Plastic models of crows were bought in UK and repainted and tails added to resemble sooty terns.
Unfortunately for some technical reason, that frankly still escapes me, the moulds and particularly their rubber interiors were not suitable for the local production of fibreglass models. So we were left with two types.
The sound system used to broadcast colony noise was purchased from a company that makes sound systems to scare pest species off crops in Europe. This was modified to play the noise of a sooty tern colony.
These different options plus control plots were combined with variations in vegetation management to generate 8 different stimuli combinations each repeated twice over the project area.
Vicki Wheeler and Tori Yates arrived at the end of May and set out the project with Chris Feare and the help of the Island Manager Camille Hoareau.
Observations were taken at set times (day and night) from a viewing platform constructed at one side of the project area. The interaction of Sooties with the trial area was recorded in terms of time spent overflying the area, height of flight and of course landings within the area. Tori and Vicki were equipped with night vision glasses to assist their nocturnal data collection.
Without going into specifics (because there are papers to be written and much more work to follow over the next 2 to 3 seasons), the area was successful in engendering interest amongst overflying sooty terns including numerous landings and demonstrating a clear preference for certain parameters.
At the end of the season models were re-positioned to reflect the favoured formulation and some 30 were re-painted as juveniles to give the impression of a successful small colony. I was supposed to follow up on this closely for another month but unfortunately broke my arm at that time and didn’t visit the island for a period of 5 weeks. However, occasional sightings by at least three individuals confirmed that the new formulation was particularly successful with 5 -10 birds seen to land at a time and numerous birds circling low overhead.
So with the results of the first season now gathered, it is for us to refine our approach accordingly for next season and hopefully optimise the scope for the establishment of a small breeding colony. It was certainly a most encouraging first year!
Tuesday, October 7, 2008
Bird Bulletin 7
Sunbird sighting: following on from my post of 15th September (in BB 6) Catherina has again sighted the male sunbird in the same location (to the north of the island) on both the 2nd and 3rd of October. Now we want to know from which of our nearest neighbours, Bird or Aride islands, the bird has originated. Catherina has also been able to get a reasonable view of the rings and I have communicated the combination to ICS, the agency that manage Aride island to see if it is one of theirs. I must also contact Nature Seychelles to see if the bird is one of those they introduced to Bird Island a couple of years ago. I will keep you informed and if the bird is indeed from Aride it will be an interesting addition to our knowledge of the species and its status on Denis (see my post dated of August 23rd for more information).
Seychelles Magpie Robin Update: love is blossoming on Denis! Well at least amongst the Magpie Robins with two more pairs appearing to establish. Most notable is the movement south of the single female from the area adjacent to territory 3 down to join the lone male there to form a new pair (see maps in side bar). Also the younger female that was co-habiting in with two other birds just south of the runway has apparently left this area, leaving anew pair behind her, and commenced floating. It is to be hoped that she will next turn up with one of the males on the northeast coast. This would result in the current optimum number of 9 pairings and hopefully engender more breeding activity. News from other territories includes:
Seychelles Magpie Robin Update: love is blossoming on Denis! Well at least amongst the Magpie Robins with two more pairs appearing to establish. Most notable is the movement south of the single female from the area adjacent to territory 3 down to join the lone male there to form a new pair (see maps in side bar). Also the younger female that was co-habiting in with two other birds just south of the runway has apparently left this area, leaving anew pair behind her, and commenced floating. It is to be hoped that she will next turn up with one of the males on the northeast coast. This would result in the current optimum number of 9 pairings and hopefully engender more breeding activity. News from other territories includes:
- T1 appears to be nest building again following the earlier loss of its chick.
- T3 are feeding their fledgling.
- T4 is currently incubating with hatching presumed imminent
- T5 is nest building after an apparent failure at egg stage of a previous breeding attempt.
Following a request for a larger map I have posted the map showing territory changes here in the body of the text. Simply click on the map to see it as a full screen version.
Crested Terns: Are still with us with eleven seen together on the southern rocks on October 3rd.
Purple Heron: I have been in contact with Mr Adrian Skerrett in his capacity as chairman of the Seychelles Bird Record Committee (see link in sidebar) and he confirms that Catherina’s sighting, recorded in my post below, is the first substantiated record of the species on Denis. Catherina will submit a completed record form and photo to the committee for their final confirmation in order to make the record official.
Sunday, October 5, 2008
Migratory Birds Report 1
As promised, as the northern hemisphere winter draws in, Catherina and I have been monitoring the occurrence of migratory birds on Denis so as to begin to establish a proper baseline of occurrence. The northern location of Denis within the Seychelles archipelago makes it an important landfall for migrating birds to either rest up en route or to stay and overwinter.
Turnstones (Arenaria interpres) and Whimbrels (Numenius phaeopus) are present all year round but numbers have increased noticeably in recent weeks. The turnstones occur in small flocks all round and on the island so overall numbers are very hard to assess. The Whimbrels however tend to aggregate particularly on the reef flats that fringe the island’s east coast and number currently between 80-90 birds.
A common sandpiper (Actitus hypoleucos) is to be seen on the east coast since September 17th and individuals of both lesser and greater Sand Plover (Charadrius mongolus & C. leschenaultii) have been seen during September. There are 3 or 4 Grey plovers (Pluvialis squatarola) on the island and its keening call is commonly heard at Belle Etoile.
On October 3rd however, Catherina saw and photographed a beautiful Purple heron (Ardea purpurea) at Belle Etoile possibly the first confirmed record (I will check on this) for this species on Denis.
Turnstones (Arenaria interpres) and Whimbrels (Numenius phaeopus) are present all year round but numbers have increased noticeably in recent weeks. The turnstones occur in small flocks all round and on the island so overall numbers are very hard to assess. The Whimbrels however tend to aggregate particularly on the reef flats that fringe the island’s east coast and number currently between 80-90 birds.
A common sandpiper (Actitus hypoleucos) is to be seen on the east coast since September 17th and individuals of both lesser and greater Sand Plover (Charadrius mongolus & C. leschenaultii) have been seen during September. There are 3 or 4 Grey plovers (Pluvialis squatarola) on the island and its keening call is commonly heard at Belle Etoile.
On October 3rd however, Catherina saw and photographed a beautiful Purple heron (Ardea purpurea) at Belle Etoile possibly the first confirmed record (I will check on this) for this species on Denis.
Saturday, October 4, 2008
Fairy Tern and Tropicbird Progress 2.
The first thing I did on arrival on Denis this week was to go and check on the fairy terns we have been following and it was good news all round.
- The first juvenile shows good development since my last report with tail feathers now fully developed “she” must be approaching full fledging.
- The second juvenile has grown dramatically! Gone is the fluffy ball of a chick from the last report and the development of proper plumage is now apparent.
- Meanwhile the fairy tern egg remains safe and sound on its branch under the attentive incubation of its parent.
Later that day I went in search of the three ground nesting tropicbirds that I first reported as a new occurrence on Denis on Sunday the 14th of September (Post entitled “Another landmark in the restoration of Denis Island”) and here also we have progress:
- The first nest area was vacant and no egg, or evidence of an egg, was apparent so the status of this “nest” is not clear. The depression left by the adult was still visible as was the presence of droppings; so the adult may have yet to lay its egg or it may be that it has abandoned the site.
- The adult was still present in the second location and I assume that it is incubating though I have yet to see an egg.
- However on going to the third site at the southern point of the island I was delighted to find a beautiful tropicbird chick. The chicks are absolutely stunning (see photo in sidebar) when young and hopefully as a ground-nesting population establishes will provide a great addition to the island’s ecotourism product. More importantly however this is the first confirmed tropicbird chick to hatch on the ground following the eradication of rats in 2002, this marks another landmark in the rehabilitation of the Denis Island ecosystem.
Managing for the future. The hot dry spell we have been experiencing on Denis recently reminded me that on other islands where I have worked in the past measures are taken to enhance locations for tropicbirds to nest. These measures focus on limiting the amount of exposure to direct sunlight by appropriate placement of palm leaves and providing greater security to the site by ringing it with stones. The latter measure in addition to providing the adult with a greater sense of safety and concealment may also serve to protect freshly hatched chicks from crab predation when adults leave to gather the chick’s first meal. It may be that the first site, if it turns out to have been abandoned, has been exposed to too much direct sunlight for the adult to cope with. So I will broach the topic with the island management in the coming days to see whether we can manage some potential nest sites in the vicinity of those already established in attempt to attract more adults into nest.
Friday, October 3, 2008
Nature Watch (2)
Dry weather: Flying in to Denis Thursday morning (2nd October) the colour of the vegetation immediately drew my attention. We have been experiencing a dry spell in the central archipelago for a few weeks and of course this is always more pronounced on the low-lying islands which by the nature of the their topography attract less precipitation. The island presents a much less verdant spectacle from the air than usual with the greens somewhat faded and many of the grassed areas showing brown. The exception to this is the foliage of the Indian almond trees in the forest which appear to be sporting a fresh growth of leaves.
Obviously dry weather has implications for the island’s entire ecosystem, in particular it typically results in a consequent reduction in insect populations. The Seychelles warbler and magpie robin are both insectivorous birds and dry weather will result in a reduction of their food source. For the warblers this will typically mean a cessation of breeding activities until the next decent period of rainfall. For the magpie robins they will rely further upon the thrice-daily stocking of their feed stations by Catherina. It is for this very reason that Catherina’s work is so important. The foundling population of robins on the island require support to maintain them in good breeding condition. It is essential for the future prospects of the population that it get off to a good start with breeding success such that numbers can increase and make the population more resilient to natural perturbations in the future. In addition to this we are taking other measures to enhance their feeding habitat and I will cover that in the next posting of the SMR news in the coming days.
That afternoon I undertook my usual walk around the island to follow up on various issues. On reaching the grassland area called “Belle Etoile” on the island’s east coast I was struck by how the grass had died back revealing features and contours of the terrain that are normally smothered by thick herbaceous growth.
I checked on the small colony of wedge-tailed shearwater burrows, that I first mentioned in my post of 18th August “Re-colonisation 2”, and was pleased to note several new burrows further down the coast. This is very encouraging and I will keep monitoring the colony in the hope of establishing proof of breeding in the coming months.
I then continued south to check on the status of the ground-nesting tropicbirds - I will post on their status and that of the fairy tern chicks we have been following in the coming days.
As I write this we are experiencing a sudden cloudburst which will certainly help to revive the vegetation and I understand from the national meteorological office that they are forecasting a normal transition into the rainy season in the coming weeks. It can’t come too soon for Denis.
Humpback whales: on the 7th of September I posted on the sighting of 3 humpback whales offshore. On the 25th and 26th September hotel guests were treated by a much closer visitation by a mother and calf which spent the best part of 2 days within a few hundred metres of the Northwest coast of the island with the mother adding to the spectacle by occasionally breaching.
I have now (11:00 hrs Friday 3rd October) just been advised that whales are again visible today off the island’s southwest coast. See my post of August 20th entitled “Marine Megafauna” for information on the fantastic wildlife to be seen in the waters around Denis.
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