Miller, N.

The management of small rookeries is key to conserving the regional genetic diversity of marine turtle populations and requires knowledge on population connectivity between breeding and foraging areas. To elucidate the geographic scope of the populations of marine turtles breeding at Bonaire and Klein Bonaire (Caribbean Netherlands) we examined the post-breeding migratory behavior of 5 female loggerheads Caretta caretta, 4 female green turtles Chelonia mydas, and 2 male and 13 female hawksbill turtles Eretmochelys imbricata during the years 2004-2013. After leaving Bonaire, the 24 tracked turtles frequented foraging grounds in 10 countries. The distances swum from Bonaire to the foraging areas ranged from 608 to 1766 km for loggerhead turtles, 198 to 3135 km for green turtles, and 197 to 3135 km for hawksbill turtles, together crossing the waters of 19 countries. Males represented the minority in this study, but we made 2 key observations that require further research: males remained in the vicinity of the breeding area for 3-5 mo, which is 2-5 times longer than females, and males migrated greater distances than previously recorded. Although the turtles dispersed widely across the Caribbean, there appeared to be 2 benthic foraging areas of particular importance to all 3 species of marine turtles breeding at Bonaire, namely the shallow banks east of Nicaragua and Honduras (n = 8 tracked turtles) and Los Roques, Venezuela (n = 3). Marine turtles breeding at Bonaire face threats from legal turtle harvesting, illegal take, and bycatch in the waters that they traverse across the Caribbean.

Sea Turtle Conservation Bonaire (STCB) was initiated in the early 1990s to protect the island’s marine turtle populations. Our current research and monitoring efforts, which were standardized more than a decade ago, include monitoring important nesting beaches around Bonaire, conducting intensive in-water netting and snorkel surveys (capture-markrecapture), and tracking post-breeding turtle migration using satellite telemetry. These techniques provide us with a better understanding of Bonaire sea turtles’ breeding success, abundance, health, residency duration, habitat quality, growth rates, migratory paths, distant feeding grounds, and threats.
During the 2013 season, we observed 77 nests at our index beach on Klein Bonaire. Total hawksbill (54) and loggerhead (23) nests documented there were similar to numbers observed during recent years. Across Bonaire and Klein Bonaire, we observed four species crawling 231 times, including 126 confirmed or suspected nests. Because our coverage of the island was not complete and weather conditions can quickly obscure crawls, these nation-wide figures represent the minimum number of crawls and nests that occurred on Bonaire and Klein Bonaire during 2013. As in previous years, nesting activities peaked during June through August. Thirty-four green turtle nests and a single leatherback nest were recorded in northeastern Bonaire, whereas hawksbills and loggerheads primarily nested on Klein Bonaire and beaches of southern Bonaire.
We observed green turtles and hawksbills along the west coast of Bonaire, around Klein Bonaire, and adjacent to Lac during snorkel surveys. Green turtle sightings were particularly high near Lac, and netting surveys also suggested large aggregations of green turtles in shallow, sea grass foraging sites of Lac. Green turtles documented there were larger than individuals reported elsewhere in Bonaire.
Five green turtles tagged in 2003 and 2006 were reported in Nicaragua’s sea turtle harvest, valuable data about sea turtle movements which complement our satellite tracking program. Unfortunately, incidences of fibropapillomatosis among green turtles were more widespread in 2013 than recent seasons.
In 2013, we tracked a post-nesting female hawksbill turtle using satellite telemetry from Bonaire to Honduras over a period of 85 days. The turtle passed through six national territorial waters, swimming over 5,000 km (3,000 mi) to reach a general area proven to be important foraging grounds for Bonaire breeding turtles.
We also outfitted a hawksbill with a datalogger to gather information on hawksbill habitat use and behaviors. The device, which collects GPS locations and depth information, was retrieved in July, 2013. Preliminary results are consistent with previously deployed dataloggers, indicating regular movements in and out of Lac Bay.
Sadly, we recorded 18 turtles stranded during 2013, 12 of which were found dead or had to be euthanized.
We will be undertaking several new research initiatives in the year ahead, including using our tagging data to estimate the total population of sea turtles using Bonaire’s waters (which will help to inform management policy) and to estimate the tremendous growth rates of green turtles in Lac, as well as reviewing our monitoring program to ensure that protocols are as efficient as possible.

We observed green turtles and hawksbills along the west coast of Bonaire, around Klein 
Bonaire, and adjacent to Lac during snorkel surveys. Green turtle sightings were 
particularly high near Lac, and netting surveys also suggested large aggregations of green 
turtles in shallow, sea grass foraging sites of Lac. Green turtles documented there were 
larger than individuals reported elsewhere in Bonaire. 
Five green turtles tagged in 2003 and 2006 were reported in Nicaragua’s sea turtle harvest, 
valuable data about sea turtle movements which complement our satellite tracking 
program. Unfortunately, incidences of fibropapillomatosis among green turtles were more 
widespread in 2013 than recent seasons. 
In 2013, we tracked a post-nesting female hawksbill turtle using satellite telemetry from 
Bonaire to Honduras over a period of 85 days. The turtle passed through six national 
territorial waters, swimming over 5,000 km (3,000 mi) to reach a general area proven to be 
important foraging grounds for Bonaire breeding turtles. 
We also outfitted a hawksbill with a datalogger to gather information on hawksbill habitat 
use and behaviors. The device, which collects GPS locations and depth information, was 
We observed green turtles and hawksbills along the west coast of Bonaire, around Klein 
Bonaire, and adjacent to Lac during snorkel surveys. Green turtle sightings were 
particularly high near Lac, and netting surveys also suggested large aggregations of green 
turtles in shallow, sea grass foraging sites of Lac. Green turtles documented there were 
larger than individuals reported elsewhere in Bonaire. 
Five green turtles tagged in 2003 and 2006 were reported in Nicaragua’s sea turtle harvest, 
valuable data about sea turtle movements which complement our satellite tracking 
program. Unfortunately, incidences of fibropapillomatosis among green turtles were more 
widespread in 2013 than recent seasons. 
In 2013, we tracked a post-nesting female hawksbill turtle using satellite telemetry from 
Bonaire to Honduras over a period of 85 days. The turtle passed through six national 
territorial waters, swimming over 5,000 km (3,000 mi) to reach a general area proven to be 
important foraging grounds for Bonaire breeding turtles. 
We also outfitted a hawksbill with a datalogger to gather information on hawksbill habitat 
use and behaviors. The device, which collects GPS locations and depth information, was 
retrieved in July, 2013. Preliminary results are consistent with previously deployed 
dataloggers, indicating regular movements in and out of Lac Bay. 
Sadly, we recorded 18 turtles stranded during 2013, 12 of which were found dead or had to 
be euthanized. 
We will be undertaking several new research initiatives in the year ahead, including using 
our tagging data to estimate the total population of sea turtles using Bonaire’s waters 
(which will help to inform management policy) and to estimate the tremendous growth 
rates of green turtles in Lac, as well as reviewing our monitoring program to ensure that 
protocols are as efficient as possible.