Sea turtles

St. Eustatius Sea Turtle Conservation Programme - Annual Report 2007

Abstract:

The St Eustatius Sea Turtle Conservation Programme was initiated in 2001 due to concerns that the island’s sea turtle populations were being threatened due to habitat degradation and destruction. The programme is managed by St Eustatius National Parks Foundation (STENAPA), which is the main environmental non-governmental organization on the island.

The Sea Turtle Conservation Programme is affiliated to the Wider Caribbean Sea Turtle Conservation Network (WIDECAST) and adopts its monitoring and tagging protocols.

Since monitoring began, three species of sea turtles have been confirmed nesting on the island; leatherback (Dermochelys coriacea), green turtle (Chelonia mydas) and hawksbill (Eretmochelys imbricata). There was an unconfirmed nesting by a fourth species, the loggerhead (Caretta caretta), in 2004.

Five nesting beaches have been identified; Zeelandia Beach, Turtle Beach, Lynch Bay, Oranje Bay and Kay Bay. Zeelandia Beach is the primary nesting beach, and the only place where all three species nest regularly; the other beaches are used occasionally by green and hawksbill turtles.

Daily track surveys are carried out on Zeelandia Beach and Turtle Beach throughout the nesting season. The other nesting beaches were monitored sporadically. Every track is identified to species; categorised as a false crawl or a nest; all nest locations are recorded for inclusion in the nest survival and hatching success study.

In 2007:

  • Track surveys were conducted daily from 8 March to 23 November; a total of 260 morning surveys were completed.
  • Leatherback nesting activity occurred from 30 March – 18 May
  • 5 leatherback nests (or probable nests) were recorded March – June on Zeelandia Beach; in addition, two false crawls and one non-nesting track were also observed on Zeelandia and Oranje Bay.
  • A leatherback nesting attempt was recorded on 18 May, 2007 on Oranje Bay. The turtle attempted to nest but hit rocks and abandoned the attempt. The non-nesting track on Oranje Bay was the first reported case of a leatherback attempt to nest on the Caribbean side of St. Eustatius.
  • All leatherback nests that were recorded were on Zeelandia Beach.
  • A member of the public reported seeing turtle tracks on Oranje Bay behind a dive centre, Dive Statia, on 11 May, 2007. The Marine Turtle Progamme Co-ordinator investigated behind the dive centre but could not find any tracks or anything resembling a nesting site.
  • Green turtles were recorded from 15 July until 16 September; 5 nests and 34 false crawls were encountered; nesting was on Zeelandia Beach but false crawls were on Zeelandia, Turtle Beach and Kay Bay.
  • Hawksbill turtles were observed from the 8 July until 13 November.Two nests and false crawls were recorded. Hawksbills nested on Zeelandia (2 nests), but recorded false crawls on Zeelandia and Crook’s Castle.

Night patrols are only conducted on Zeelandia Beach due to limited personnel and minimal nesting on other beaches; patrols run from 9.00pm – 4.00am. Each turtle encountered is identified to species; tagged with external flipper tags and an internal PIT tag (leatherbacks only); standard carapace length and width measurements are taken; nest locations are recorded for inclusion in the nest survival and hatching success study.

In 2007:

  • Night patrols were conducted from 30 March – 26 September; 119 patrols were completed, totalling 719.22 hours of monitoring.
  • Three leatherback, one green turtle and two hawksbill turtles were encountered during patrols; all leatherbacks received external flipper tags.
  • The first green turtle was observed on 29 July. She successfully nested and had a tag which showed that she was tagged previously in 2002. She was also observed in 2005. This turtle nested approximately four times during the 2007 season including 2 September 2007 when she was fitted with a satellite transmitter.
  • No hawksbills were tagged during the 2007 season. Two hawksbills were seen but one did not break the high tide line while the other was unable to be tagged.
  • One green turtle during the night patrol was selected for satellite tracking in 2007. This was the last satellite transmitter that was applied for the DCNA Turtle Tracking Project. This has been the third consecutive year that the Dutch Caribbean Nature Alliance Satellite Tracking Project has been conducted and successfully accomplished.

Average carapace measurements for females nesting in 2007:

  • Leatherback: Curved carapace length (CCL) = 147.00 cm; Curved carapace width (CCW) = 110.3 cm
  • Green: CCL = 110.0 cm; CCW = 105.5 cm o Hawksbill:CCL=88.0cm;CCW=73.0cm.

All marked nests were included in a study of nest survival and hatching success. During track surveys they are monitored for signs of disturbance or predation; close to the expected hatching date the observers record signs of hatchling emergence. Two days after hatchling tracks have been recorded the nest is excavated to determine hatching and emerging success.

In 2007:

  • 12 nests were marked: five leatherbacks, five greens and two hawksbill nests.
  • 2 nests were lost during the incubation period; both were leatherback nests lost due to high tides near natural nests near stake 22-25.
  • Mean incubation period for leatherbacks was 58 days, for greens 55.25 days and for hawksbills was indeterminable since none survived.
  • One hawksbill nest was laid on Zeelandia beach on 12 November. A local resident observed hatchlings on 31 December but after 11 days of searching, the nest could not be relocated and the nest (EI0702R) was declared “Partially Hatched”.

Excavations were performed on 12 nests; five leatherbacks, five greens and two hawksbill nests.

  • Average egg chamber depth varied between the three species: leatherback = 64.67 cm, green = 53.25cm and hawksbill = 53cm.
  • Mean clutch size for each species: leatherback = 66 yolked + 30.7 yolkless eggs and green = 130 yolked + 0.25 yolkless eggs. Hawksbills are indeterminable since none hatched successfully.
  • Five nests hatched or partly hatched leaving one that washed away by the tide (CM0705); two that could not be located and three that failed to hatch.
  • Leatherbacks showed identical hatching and emerging success rate from 2006; 21.16% hatching success compared to 21.1%, but higher emerging success of 64.58% to just 15.3% in 2006.
  • Greens were more successful in 2006 and hatching success was 33.84% compared to 51.0% in 2006, but emerging success was 57.18% in 2007 and 46. 2006.
  • The survival of nests varied but overall was not very high. All nests were laid on Zeelandia Beach.
  • In future years the practise of relocating nests laid erosion zones to safer sections of the beach will continue.

On 29 April, 2007, a stranded leatherback turtle was encountered by the Marine Park intern, Mirella Wognum, on Zeelandia Beach during a morning track survey at approximately 08:15. Lacking the necessary equipment to perform a necropsy turtle was moved above the surf line, to ensure that it was not swept away by the tide. Later that day the remains the turtle washed northward to stake number 1. The Programme Co-ordinator, , assisted by Marine Park interns Liz Hartel and Mirella Wognum, returned and performed a rudimentary necropsy to try and determine the cause of death.

On the morning of 16th of May, STENAPA staff came across a drowned Hawksbill on the City Harbor. The juvenile hawksbill had been trapped in the net of a local fisherman and could not free itself from the nets, subsequently drowning.

On the 7th of November, a stranded Green Turtle was discovered by a local diver, Derrick Goudrian, in Oranje Bay nearby dive site Blue Bead Hole. Mr. Goudrian presented the deceased turtle to STENAPA staff which took photos and buried the juvenile Green nearby Zeelandia beach. Unfortunately the Programme Coordinator was away on holiday and unable to perform a necropsy.

A satellite tracking project was initiated in 2005 by the Dutch Caribbean Nature Alliance (DCNA) and concluded in 2007. This research was an inter-island collaboration between STENAPA and the Nature Foundation St Maarten. Dr Robert van Dam was the lead biologist, providing expertise and training in satellite telemetry methodology.

The two turtles tracked by satellite since 2006 continued into 2007. In mid-September 2006, two turtles received their tracking satellites. Lisa, a hawksbill turtle, was fitted with a satellite transmitter while Grace, the green turtle, was fitted a transmitter. Lisa’s last transmission was 1 February 2007. From the time of her nesting on Zeelandia beach until the time of her last transmission, Lisa had traveled a total of 2870km. Grace transmitted from sea grass beds off the waters of St. Kitts and Nevis. Grace’s last transmission was on 6 June 2007 at 18:18:09. During the lifetime for the transmission, Grace traveled a total of 4412km in her foraging grounds.

  • On 1 September 2007, a green turtle arrived on Zeelandia Beach at 23:27. She was previously recorded in 2002 and in 2005. The Green turtle, named “Track”, attempted to nest but found the area she chose too rocky. On her wa back to the water she was placed in a turtle holding pen and her satellite transmitter was activated at 00:11. She was released back into the ocean at 03:20, Sunday the 2nd of September.
  • All STENAPA volunteers and interns, along with Arturo Marine Turtle Programme Coordinator, as well as several local residents were present for this major event. The entire process was videotaped by Dwight Ba and aired on Channel 15 on 6 September from 7:30 to 8:00pm.
  • Track made a brief stop at Prickly Pear Island in the itish Virgin Islands. Track then skimmed the northern coast of Puerto Rico and stopped the north-east coast of Dominican Republic. At the time of writing this report, Track was currently in the same feeding grounds of El Macao, Santo Domingo.
  • STENAPA has been in contact with Yolanda Leon, a known turtle biologist from the Dominican Republic. Ms Leon stated that there are many beaches in the area where Track is located. Track entered an area of intense tourism development, however, there are nearby areas with less developed beaches and offshore sea grass. One particular beach in this area was a historically important leatherback nesting beach.
  • Track’s satellite transmitter stopped responding approximately 23 December 2007. At her last transmission, she was still in the same feeding grounds as previously indicated.
  • In concurrence with attaching the final satellite transmitter, the Marine Turtle Programme Coordinator visited all the island schools to give a brief presentation to all students. The motive for these visits was to educate and inform the local students of two different competitions in relation to this project.

Beach erosion continued on Zeelandia Beach in 2007:

  • Many of the numbered marker stakes were lost due to high tides. Approximately, 21 were replaced.
  • Beach mapping and erosion monitoring was continued this year. Data were collected February, May, August and December. Data was compared for seasonal changes as well as yearly changes. All months were compared for within the year changes. 28.13% of the stakes had recorded a positional change from the cliffs that were less than 50cm from their December positions. 40.63% of the stakes recorded a positional change of 50-100cm while 29.69% of the stakes recorded a change of over 100cm. Seventeen of the stakes moved between one to two meters while two moved more than two meters. The data do point to extensive cliff erosion, and possibly steady to accelerating erosion. Preliminary data stills needs multiple year analyses before any tangible conclusions can be made.
  • Sand mining compounds the erosion problem at the northern end of Zeelandia Beach. Despite being an illegal activity, it occurred throughout 2007, in the gully and on the beach.
  • Seven major cliff falls and 16 minor cliff falls were recorded from February to December. o Monitoring of erosion will be a priority for 2008. A suggestion for 2008 is to monitor erosion rates and create a water table study to see if there is a correlation.

Several different community activities were conducted in 2007:

  • In 2005 the “Help Out or Sea Turtles Miss Out” programme, teaching the local communities about sea turtle conservation issues, with Education Officer Dominique Vissenburg, was particularly successful. In 2006/7, the year the focus of the school education programme was water.
  • On 11 February, 2007 the Marine Turtle Program Co-ordinator gave a presentation to the public. The title of the presentation was regarding the conservation of marine turtles on St. Eustatius. Among the persons present were eight University of St. Eustatius medical students.
  • On 21 March, 2007, a presentation was given to STENAPA’s Junior Rangers regarding the history of turtles in the Caribbean, their current threats and laws protecting them. The presentation was called “Sea Turtle Conservation And Laws Protecting Them”. Furthermore, in the month of December, there were also sessions with Junior Ranger I and II regarding marine turtles and their habitat.
  • During July 2007, STENAPA started its inaugural STENAPA Summer Club. Twenty-four children aged eight to 13 signed up for the club which included hiking, snorkeling and turtle education activities. STENAPA’s Summer Club ran from 2 July to 2 August every Monday, Wednesday and Thursday.
  • On 5 December, in conjunction, with the St. Eustatius Marine Park 10 year anniversary, a one hour seminar for the general public was given on the Biology, Ecology and History of Turtles in St. Eustatius Marine Park at the Golden Era Hotel.

Twelve beach clean-ups were conducted on Zeelandia Beach. Cleanups were performed on Zeelandia Beach, Turtle Beach, Lynch Beach and Oranje Bay. This was the first recorded time that Lynch Beach had rubbish removed from its beach. The September cleanup coincided with Ocean Conservancy’s International Coastal CleanupTM Campaign on 15 September. Beach cleanups were carried out by the Sea Turtle Conservation Programme Coordinator, STENAPA board, staff and interns, Working Abroad volunteers, local citizens and BroadReach volunteers.

  • A total of 22 trucks full of rubbish bags were removed, including a large mooring rope, fishing nets, oil barrel, fishing ropes and buoys, several pallets.
  • Local citizens were on hand in several beach cleanups (March, July and September).
  • On 15 September 2007, volunteers gathered on Zeelandia Beach to participate in the largest singular most successful worldwide volunteer movement, the International Coastal Cleanup. This particular beach clean up was unique because it was the first time St. Eustatius National Parks, STENAPA, collaborated with The Ocean Conservancy on this event.
  • During EnviroWeek in the week of 16 October the Junior Rangers, led by Parks Ranger Hannah Leslie, a cleanup was conducted on Venus Bay. This was the first recorded cleanup of Venus Bay by STENAPA.

The Sea Turtle Conservation Programme was featured in regular articles in the local press, Television and on the radio. The STENAPA quarterly newsletter included several features about the research activities conducted in 2007 and the new website contains several pages dedicated to the programme, with a focus on the culmination of the DCNA Sea Turtle Satellite Tracking Project.

A new approach was taken for the upcoming season in generating interest from the local population of St. Eustatius. The Marine Turtle Program Co-ordinator spoke with several interested members who were keen to view the nesting activity of turtle, nest exhumation or a hatchling release. A turtle phone was purchased with a list of interested people to contact when there were possibilities for seeing turtles. The new approach was popular avenue and a grassroots approach of connecting with marine turtles.

Staff participated in several regional and international meetings in 2007:

  • The Programme Co-ordinator, Arturo Herrera, attended the 27th International Sea Turtle Symposium in Myrtle Beach, South Carolina USA from 25 to 28 February 2007) and the WIDECAST Annual General Meeting (23 – 24 February 2007).
  • On the first week of December, STENAPA held its Ten Year Marine Park Celebration. Many activities were included and one was the hour-long Marine Turtle presentation held at the Golden Era Restaurant and Hotel on 5 December 2007.

On 10 June, 2007, STENAPA greeted its first Marine Turtle Intern, Shizu Fukui to St Eustatius. Shizu Fukui is the first Marine Turtle Intern and has d previous experience working with marine turtles, especially, leatherback turtles, in 2006 in Gandoca Costa Rica. Her duties included organizing the turtle aspect of the STENAPA Summer Club, creating a STENAPA Turtle Volunteer Manual, and spearheading a Zeelandia Beach beautification project, as well as night patrolling, morning beach surveys and habitat surveying dives.

In June 2007, the Zeelandia beautification project commenced. The primary objective is to offer an area on Zeelandia Beach where visitors can enjoy the beach. Another objective is to deter vehicles from driving on the beach, stop sand mining and prevent further erosion. On 15 June 2007, a visitor information board was installed at the primary entrance to Zeelandia Beach. 20 July 2007 was dedicated to the installation of plants and fencing at the prime Zeelandia entrances. On 7 September 2007, another Family Friday was dedicated to replanting of palm trees and yucca plants that succumbed to the warm weather. Three signs have been strategically placed at the entrances. The purpose of these signs is to educate the public about turtles that nest on the beach and remind people not to drive on the beach. STENAPA intern for the Turtle Programme, Zoe Fukui lead this project and hopes the signs will inform the public about the work of the Marine Park to protect turtles by means of nightly turtle patrols, cleaning the beach and protecting the beach from erosion.

The In-Water Survey and Monitoring project was initiated in January 2007 in order to provide fundamental data on the populations and trends of resident and migrant turtle species that use the surrounding waters of St. Eustatius. The information gathered will be used to monitor, detect trends and assess the habitats where turtles rest, nest and feed. The objective is to build on existing knowledge of the population demographics of marine turtles in the St Eustatius Marine Park. There are no previous in-water studies about the resident sea turtle populations in the area. Equipment such as ArcGIS 9.0 Software and Satellite Imagery was purchased to begin the habitat mapping of the areas where resident turtles may reside. The first habitat map for the Marine Park was produced in May 2007.

Management Recommendations:

Several recommendations are made for the 2008 season:

  • Continued participation of volunteers, from Working Abroad and the STENAPA Intern Programme.
  • Foster public awareness of the Turtle Programme within the island of St Eustatius and the Netherlands Antilles. Utilize the new television medium along with Dwight Barran to videotape a nesting female turtle for a documentary on nesting females on St. Eustatius.
  • Continue with month-long STENAPA Summer Club and have the Turtle Education feature integrated into a fundamental component.
  • Monitoring of nesting beaches to continue: daily track surveys on all beaches and night patrols of the primary nesting beach.
  • Further development of the research programme: expand the focus of the programme by implementing an in-water survey of juvenile turtles and continue the satellite tracking project.
  • A proposal to extend the satellite tracking to leatherback turtles for DCNA.
  • Monitoring of erosion should also become a priority. In addition, monitor the water table at Zeelandia beach to determine if the subterranean water levels are causing possible egg failure but more importantly accelerating possible beach erosion.
  • As well as the monitoring of erosion, continue to develop the Zeelandia Beautification Project to include a concrete turtle and possible a picnics area for individuals interested in the beauty of Zeelandia Beach.
  • Revitalize the in-water turtle sighting surveys with the local diving centres. This information will help make more informed decisions regarding the in-water monitoring programme.
  • Create a turtle baseline study within the Marine Park and a carrying capacity survey. 
Date
2008
Data type
Research report
Theme
Research and monitoring
Geographic location
St. Eustatius
Author

St. Eustatius Sea Turtle Conservation Programme - Annual Report 2006

Abstract:

The St Eustatius Sea Turtle Conservation Programme was initiated in 2001 due to concerns that the island’s sea turtle populations were being threatened due to habitat degradation and destruction. The pro gramme is managed by St Eustatius National P arks Foundation (STENAPA), which is the main environmental non-governmental organization on the island.

The Sea Turtle Conservation Programme is affiliated to the Wider Caribbean Sea Turtle Conservation Network (WIDECAST) and adopts its monitoring and tagging protocols.

Since monitoring began, three species of sea turtles have been confirmed nesting on the island; leatherback (Dermochelys coriacea), green turtle (Chelonia mydas) and hawksbill (Eretmochelys imbricata). There was an unconfirmed nesting by a fourth species, the loggerhead (Caretta caretta), in 2004.

Five nesting beaches have been identified; Zeelandia Beach, Turtle Beach, Lynch Bay, Oranje Bay and Kay Bay. Zeelandia Beach is the primary nesting beach, and the only place where all three species nest regularly; the other beaches are used occasionally by green and hawksbill turtles.

Daily track surveys are carried out on Zeelandia Beach and Turtle Beach throughout the nesting season. Weekly track surveys were carried out on Oranje Bay following the report of a hawksbill track on 1 June. The other nesting beaches were monitored sporadically. Every track is identified to species; categorised as a false crawl or a nest; all nest locations are recorded for inclusion in the nest survival and hatching success study.

In 2006:

  • Track surveys were conducted daily from 20 March to 24 November; a total of 232 morning surveys were completed.
  • Leatherback nesting activity occurred from 17 March – 14 June; 10 nests and two false crawls were observed; all emergences were on Zeelandia Beach.
  • Green turtles were recorded from 27 May until 18 September; 34 nests and 57 false crawls were encountered; nesting was on Zeelandia Beach, Turtle Beach and Kay Bay.
  • Hawksbill turtles were observed from the 3 June until 19 September. Six nests and two false crawls were recorded; hawksbills used Kay Bay (3 nests), Zeelandia Beach (1 nest) and Oranje Bay (2 nests).

Night patrols are only conducted on Zeelandia Beach due to limited personnel and minimal nesting on other beaches; patrols run from 9.00pm – 4.00am. Each turtle encountered is identified to species; tagged with external flipper tags and an internal PIT tag (leatherbacks only); standard carapace length and width measurements are taken; nest locations are recorded for inclusion in the nest survival and hatching success study.

In 2006:

  • Night patrols were conducted from 12 April –06 October; 127 patrols were completed, totalling 812.75 hours of monitoring.
  • One leatherback, three green turtles and one hawksbill turtle were encountered during patrols; all were tagged by the Programme Co-ordinator.
  • One remigrant green turtle returned to nest in the 2006 season. This green turtle was first observed on 19 July.
  • One green turtle and one hawksbill turtle during the night patrol were selected for satellite transmission in 2006. This has been the second consecutive year that the Dutch Caribbean Nature Alliance Satellite Tracking Project has been conducted and successfully accomplished.

Average carapace measurements for females nesting in 2006:

  • Leatherback: Curved carapace length (CCL) = 158.7 cm; Curved carapace width (CCW) = 114.8cm
  • Green: CCL = 107.0 cm; CCW = 64.9cm
  • Hawksbill: CCL = 85.5 cm; CCW = 75.0 cm.

All marked nests were included in a study of nest survival and hatching success. During track surveys they are monitored for signs of disturbance or predation; close to the expected hatching date the observers record signs of hatchling emergence. Two days after hatchling tracks have been recorded the nest is excavated to determine hatching and emerging success.

In 2006:

  • 50 nests were marked: 10 leatherbacks, 34 greens and six hawksbill nests.
  • 21 nests were lost during the incubation period; 15 green nests and six hawksbill nests were presumed to be washed away during high tides in October; one leatherback nest was washed over by the tide for three days causing inundation; All hawksbill nests were presumed to be lost, with one hawksbill nest inundated before being moved on 18 October.
  • Mean incubation period for leatherbacks was 64.3 days, for greens 51.1 days and for hawksbills was indeterminable since none survived.

Excavations were performed on 20 nests; six leatherbacks, 13 greens and one hawksbill.

  • Average egg chamber depth varied between the three species: leatherback = 68.6 cm, green = 54.4cm and hawksbill = 48.2cm.
  • Mean clutch size for each species: leatherback = 76.2 yolked + 34.2 yolkless eggs; green = 101.2 eggs and hawksbill = 131 eggs.
  • Hatching success was greater for green nests than either hawksbill or leatherback: 51% compared to 0.00 % and 21.1%, respectively.
  • Leatherbacks hatching success improved from the 2005 season, increasing from 3.5% to 21.1% in 2006.
  • All hawksbill nests were lost for the 2006 season. This was due to a culmination of reasons. Mostly because of laying in Oranje Bay and Kay Bay which has a limited area available for nesting and those areas washed away by high tides later on in the season. The one nest laid on Zeelandia was inundated for an unknown period of days before being relocated causing nest failure.
  • Emerging success was lower for leatherback than greens; 15.3 % compared to 46.4 %, respectively.
  • Very little predation was observed and a few deformed embryos were recorded; one nest had several hatchlings with deformed carapaces; one had an incomplete skull and no eyes present while another green hatchling had two sets of jaws. One green turtle egg contained twin embryos, and 11 albino green turtle hatchling was also found. Ten were found from one nest.
  • Six nests were relocated during the 2006 season; one hawksbill nest, one leatherback nest and four green turtle nests. The hawksbill nest was laid on 7 September but due to the risk of erosion from freshwater run-off from the surrounding cliff, was relocated 19 October. The eggs appeared to have been affected by the run-off.
  • The leatherback nest was immediately relocated whilst being laid. Unfortunately, the eggs were unfertilised.
  • Of the four green turtle nests that were relocated; two hatched, one was washed away and one failed to hatch.
  • In future years the practise of relocating nests laid in erosion zones to safer sections of the beach will continue.

On 27 September, a dead hawksbill turtle was encountered by the Programme Co-ordinator on Turtle Beach during a morning survey. At the current time, the Co-ordinator was lacking the equipment to perform a proper necropsy, but the turtle was moved and a necropsy was performed later. A rudimentary necropsy to determine the cause of death. Unfortunately no definitive answer as to the cause of death was determined from the necropsy.

A satellite tracking project was initiated in 2005 by the Dutch Caribbean Nature Alliance (DCNA) which was continued in 2006. This research was an inter-island collaboration between STENAP A and the Nature Foundation St Maarten. Dr Robert van Dam was the lead biologist, providing expertise and training in satellite telemetry methodology.

  • Two transmitters were successfully deployed on nesting females; one on a green turtle (“Grace”) that nested on Zeelandia on 17 September, the other was a hawksbill (“Lisa”) that nested on Zeelandia on 7 September. The turtles’ names were taken from two competitions that were organised for students for the “Name the Turtle” Competition in 2005.
  • The green turtle initially went off towards St Kitts, but then headed back towards Statia and returned to nest once more (29 September). The night patrol found her after nesting as she was returning to the ocean. They double-checked to make sure the transmitter was properly attached and it was. She then moved in between St Kitts and Nevis in presumably near-shore waters of the island. We suspect that she is in foraging grounds. As early as December, Grace has travelled a total distance of 1700 km.
  • Lisa was the first hawksbill observed nesting on St Eustatius for the 2006 season. The last observed hawksbill was in the 2004 season. She took off from Statia, and headed straight to St Barts. She remained around the uninhabited islands between St Barts and St Maarten for over two weeks before moving to Anguilla for a few days. In late September she started moving again, and travelled to the US Virgin Islands where she stayed until approximately 7 October. Then the hawksbill started out for open water and appeared to head back towards Anguilla but veered to the uninhabited islands between St Maarten and St Bartholomew again in mid October. Lisa moved just off the southeast point of St Maarten but returned to the uninhabited islands around 10 November where she has been since.

Beach erosion continued on Zeelandia Beach in 2006:

  • Many of the numbered marker stakes were lost due to high tides. Approximately, twenty were replaced.
  • A new method of beach mapping and erosion was undertaken this year. Data were collected in July and November and compared within the year. 64% of the stakes had recorded a positional change from the cliffs that were less than 50cm from their July positions. Only one stake recorded more than 2m cliff erosion from its July location. Although the data does not suggest extensive cliff erosion, the data points to possible steady erosion. Preliminary data stills needs multiple year analyses before any tangible conclusions can be made.
  • Sand mining compounds the erosion problem at the northern end of Zeelandia Beach. Despite being an illegal activity, it occurred throughout 2006, in the gully and on the beach.
  • In addition to the illegal sand mining, the Executive Council of the Island Government agreed to a one-year policy of sand mining to curb the sand shortage for construction on St Eustatius. This policy started 11 October and will be a temporary solution that will be monitored with certain steps placed to minimise the impact on Zeelandia Beach. None of the preparation steps agreed to have been implemented but the Executive Council has already permitted one sand mining operation to proceed on 1 November.
  • Four major cliff falls and four minor cliff falls were recorded from June to October.
  • Monitoring of erosion will be a priority for 2007. A suggestion for 2007 is to monitor erosion rates and water table to see if there is a correlation.

Several different community activities were conducted in 2006:

  • A puppet show was organised for local schools and the after school programme to teach about water quality with a turtle, Scout, as the main puppet in the theme.

Ten beach clean-ups were conducted on Zeelandia Beach. A total of 16 trucks full of rubbish bags were removed, including a partial radiator, water heater, large rope, fishing nets, oil barrel, a plastic barrel, four large batteries and several car batteries. Unfortunately it was difficult to attract support from the local community despite visits to schools to notify classes.

The Sea Turtle Conservation Programme was featured in regular articles in the local press and on the radio. The STENAPA quarterly newsletter included several features about the research activities conducted in 2006 and the new website contains several pages dedicated to the programme, with a focus on the Sea Turtle Satellite Tracking Project 2006.

Staff participated in several regional and international meetings in 2006:

  • The Programme Co-ordinator, Emma Harrison attended the 26th International Sea Turtle Symposium in Crete, Greece 3 – 8 April, 2006 and the WIDECAST Annual General Meeting.
  • The Programme Co-ordinator travelled to Puerto Rico from 11 – 19 March, to participate in the in-water monitoring programme of juvenile green and hawksbill turtles at foraging sites close to Culebra Island. The purpose was to receive training in a protocol for conducting in-water capture of turtles, possibly implementing the techniques on Culebra Island to the St. Eustatius in-water monitoring programme.
  • On 16 August, STENAPA held its first Annual Public Meeting upstairs at the government guesthouse. At the Annual P ublic Meetin g, Dr Harr ison, gave a presentation on the Sea Turtle Conservation Programme.
  • In September, the Programme Co-ordinator was the opening night speaker of the “Sea & Learn on Saba” event. The work of the Sea Turtle Conservation Programme was presented to international biologists, tourists and local residents. The focus of the presentation was satellite tracking and its role in the conservation of Caribbean Sea turtles.

Management Recommendations:

Several recommendations are made for the 2007 season:

  • Continued participation of volunteers, from Working Abroad and the STENAPA Intern Programme. To extend volunteer participation, and arrange a dedicated Sea Turtle intern(s) for the upcoming 2007 season.
  • Monitoring of nesting beaches to continue: daily track surveys on all beaches and night patrols of the primary nesting beach.
  • Further development of the research programme: expand the focus of the programme by implementing an in-water survey of juvenile turtles and continue the satellite tracking project. There is a proposal to extend the satellite tracking to leatherback turtles for 2007.
  • Monitoring of erosion should also become a priority. In addition, monitor the water table at Zeelandia beach to determine if the subterranean water levels are causing possible egg failure but more importantly accelerating possible beach erosion.
  • As well as the monitoring of erosion, continue to monitor the sand mining approved by the Executive Council of the Island Government and develop alternatives, including instigating a study to assess sustainability of sand mining and impact to the beach nourishment process.
  • Include schoolchildren in carrying out beach cleanups. Arrange a contest to see who can collect the most rubbish and award a prize to the winner of the competition.
  • Integrate The Ocean Conservancy’s International Coastal CleanupTM Campaign with monthly beach cleanups. The Ocean Conservancy organizes a worldwide annual cleanup on 16 September.
  • Revitalize the in-water turtle sighting surveys with the local diving centres. This information will he lp make more informed decisions regarding the in-water monitoring programme. 
Date
2007
Data type
Research report
Theme
Research and monitoring
Geographic location
St. Eustatius

Activity Report on the Dutch Caribbean Nature Alliance Sea Turtle Satellite Tracking Project 2005

In June funding from the Dutch Caribbean Nature Alliance (DCNA) was confirmed to initiate a satellite tracking project of sea turtles on St Eustatius and St Maarten, with collaboration from the St Eustatius National Parks Foundation (STENAPA) and the Nature Foundation St Maarten. The object of this study was to determine the migration pathways and feeding grounds of the islands’ nesting green and hawksbill turtles.

The purpose of this report is to summarise the activities of the DCNA Sea Turtle Satellite Tracking Project 2005, with specific reference to public awareness activities on St Eustatius and media coverage of the project. 

Date
2006
Data type
Research report
Theme
Education and outreach
Research and monitoring
Geographic location
St. Eustatius
St. Maarten
Author

St. Eustatius Sea Turtle Conservation Programme - Annual Report 2012

The aims of this Annual Report include the following:

 Summarize the activities of the 2012 Sea Turtle Conservation Program.

 Review the accomplishments and deficiencies of the program in 2012.

 Suggest recommendations for the 2013 program.

 Provide a summary of the data from 2012 research initiatives.

 Present information locally, regionally and internationally about the research and monitoring program on the island.

 Produce a progress report for the Island Government, potential program funding organizations, the local community and international volunteers

Date
2013
Data type
Other resources
Theme
Research and monitoring
Geographic location
St. Eustatius
Author

Research and Monitoring Report 2012 - Sea Turtle Conservation Bonaire

Sea Turtle Conservation Bonaire proudly presents its 2012 Bonaire Sea Turtle Research and Monitoring Report.
In this report you will read about the methods and results of our sea turtle research and monitoring activities, which include nesting beach monitoring, foraging ground surveys, turtle migration tracking, and responding to reports of turtle strandings. With our nesting beach monitoring, we track turtle nesting activity, determine nest size and productivity, and estimate the number of hatchlings produced. With our foraging ground surveys we capture, tag, measure and photograph individual turtles and establish catch-per-unit-effort measures of turtle abundance. We inspect the turtles for signs of illness or injury, including fibropapillomatosis. Our recapture of previously tagged turtles provides valuable insight into turtle residency duration, home range, growth rates, and habitat quality. With satellite telemetry, we are able to identify the migration paths and distant feeding grounds used by our breeding and nesting turtles. Our follow-up on reports of turtle strandings has resulted in the occasional rescue of sea turtles and has helped us to identify threats and take actions to mitigate problems.
New research was started in 2012 with funding from IMARES (the Institute for Marine Resources and Ecosystem Studies in the Netherlands). Using abundance surveys and deploying dataloggers we began to study the foraging use of Lac by hawksbill turtles. The results so far demonstrate that these turtles regularly move in and out of the bay, and indicate that this area is an important turtle foraging area for not only green but hawksbill turtles as well. This continuing research will be helpful in strengthening our case for the importance of protecting Lac.
We use the information gathered in our research and monitoring activities to identify and implement conservation, education, and advocacy efforts needed to ensure protection of Bonaire’s sea turtles. We also use sea turtle conservation as a focal point to drive and stimulate general conservation awareness and efforts. For information about these other important activities of STCB, please visit our STCB website

 

Date
2013
Data type
Research report
Theme
Research and monitoring
Geographic location
Bonaire
Author

Sea Turtle In-water Monitoring Survey 2011

Seven sea turtles species inhabit the world’s oceans today and have a unique evolutionary lineage that dates back at least 110 million years.Sea turtle populations are declining worldwide due to different factors such as destruction and/or modification of habitats, nesting beaches being degraded by sand mining as well as commercial and tourist development, foraging grounds have been altered or destroyed, pollution, increased shipping traffic and recreational activities. Changes in the populations of juveniles and sub-adults are a early indicator for assessing the future of the sea turtle population as a whole. In-water surveys of sea turtle foraging grounds are a good tool to monitor population changes
A total of 35 in-water transects were made, two tour dives, one in day time and one at night and observations from the boat were made during the transect time by the captain. The in-water turtle survey was conducted between February and July 2011 within St.Eustatius National Marine Park boundaries.
A total of 16 sea turtles (11 greens sea turtles and five hawksbills) were observed during 25 hours and 20 minutes of dive time that includes transect dives, two tour dives and turtles observed from the boat during the transect time, yielding a Catch Per Unit E ffort of 0.63 within the marine park boundaries. During the 35 transect dives, seven sea turtles were recorded, four of them were green sea turtles and three were hawksbills. During the two tour dives seven sea turtles were recorded, six of them were green sea turtles and one was a hawksbill. The total number of observed turtles by the captain on the boat was two sea turtles, one green sea turtle and one hawksbill.

Date
2011
Data type
Research report
Theme
Research and monitoring
Geographic location
St. Eustatius
Author

Estimating sex ratios in Caribbean hawksbill turtles: testosterone levels and climate effects

Evolutionary theory predicts that male and female offspring should be produced at a 1:1 ratio, but this may rarely be the case for species in which sex is determined during incubation by temperature, such as marine turtles. Estimates of primary sex ratio suggest that marine turtle sex ratios are highly skewed, with up to 9 females per male. We captured juvenile hawksbill turtles Eretmochelys imbricata in waters around Anegada, British Virgin Islands, a regionally important foraging aggregation, and analysed concentrations of plasma testosterone and oestradiol-17β from 62 turtles to estimate sex ratio. There were 2.4 to 7.7 times more females than males. Testosterone concentrations correlated with sampling date and sea surface temperature (SST), with higher concentrations in the late summer when SST was highest, suggesting that assigning sex through threshold values of sex hormones must be carried out cautiously. The sex ratio in the juvenile foraging aggregation around Anegada is more male biased than at other locations, suggesting that turtles at Anegada have resilience against feminising effects of climate change. Future work should (1) integrate the relative contributions of different genetic stocks to foraging aggregations and (2) investigate the annual and seasonal cycles of sex hormones, and differences among individuals and life history stages. 

Date
2013
Data type
Scientific article
Theme
Research and monitoring
Journal

Marine turtles of the Leeward Islands, Lesser Antilles

Although marine turtles are conspicuous members of the Caribbean fauna, significant gaps remain in our knowledge of their distribution and status within the region. Nowhere is knkledge more fragmentary than for the Lesser Antilles which, following the definition of Bond (1978) , include those islands fro:> Saba and Anguilla south and east to Barbados and Grenada. Comprising 17 major islands and 16 banks, the Lesser Antilles lie in an arc some 630 km long, and provide nesting and foraging habitats for four species of marine turtles: the green turtle (Chelonia mydas) , hawksbill (Eretmochelys imbricata) , leatherback (Dermochelys cor iacea) and loggerhead (Caretta caretta) . Although the olive ridley (Lepidochelys olivacea) .occurs peripherally in the wider Caribbean region, it is considered a waif in the Lesser Antilles. Kemp's ridley (Lepidochelys kempi) has not been recorded from this region.

Date
1983
Data type
Scientific article
Theme
Research and monitoring
Geographic location
Saba
St. Eustatius
St. Maarten

A Stage-Based Population Model for Loggerhead Sea Turtles and Implications for Conservation

Management of many species is currently based on an inadequate under- standing of their population dynamics. Lack of age-specific demographic information. particularly for long-lived iteroparous species. has impeded development of useful models. We use a Lefkovitch stage class matrix model. based on a preliminary life table developed by Frazer (1983a), to point to interim management measures and to identify those data most critical to refining our knowledge about the population dynamics of threatened log- gerhead sea turtles (Caretta caretta). Population projections are used to examine the sen- sitivity of Frazer's life table to variations in parameter estimates as well as the likely response of the population to various management alternatives. Current management practices appear to be focused on the least responsive life stage. eggs on nesting-beaches. Alternative protection efforts for juvenile loggerheads. such as using turtle excluder devices (TEDs). may be far more effective. 

Date
1987
Data type
Scientific article
Theme
Research and monitoring
Journal