Patterns of dispersal of hawksbill turtles from the Cuban shelf inform scale of conservation and management

Moncada, Félix; Hawkes, Lucy A.; Fish, Marianne; Godley, Brendan J.; Manolis, S. Charlie; Medina, Yosvani; Nodarse, Gonzalo; Webb, Grahame J. W.

doi:10.1016/j.biocon.2012.01.011

Cited by 30 publications

(34 citation statements)

References 45 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Of particular interest were individual-level variations in movement patterns, which leads to further questions regarding how the regional population uses this habitat and the ecological mechanisms underlying different behaviors. This evidence adds to that found in other sites within the Caribbean (Moncada et al 2012, Revuelta et al 2015, suggesting that locally increased marine protection in the area might positively impact this species and also lead to hawksbills being used as an alternate umbrella species for coral reefs (Weng et al 2015).…”

Section: Patterns Of Movementsupporting

confidence: 60%

Movement patterns of juvenile hawksbill turtles Eretmochelys imbricata at a Caribbean coral atoll: long-term tracking using passive acoustic telemetry

Chevis¹,

Godley²,

Lewis³

et al. 2017

Endang. Species. Res.

View full text Add to dashboard Cite

Understanding the ecological interactions that underlie marine ecosystem functioning requires sufficient data describing habitat use by mobile species. Hawksbill turtles Eretmochelys imbricata are considered a key species in coral reef-associated communities, owing to their specific foraging preferences, yet new information is still revealing details of the spatial and temporal aspects of habitat use. We used passive acoustic telemetry to monitor the movements of 18 juvenile hawksbills (minimum curved carapace length: 32.0−59.7 cm, mean ± SD = 43.9 ± 6.7 cm) at a developmental foraging site in a Mesoamerican barrier reef, Lighthouse Reef Atoll in Belize (tracking duration 10−1414 d, mean ± SD = 570 ± 484 d). Although specific home ranges were difficult to quantify, several turtles showed high site fidelity over timescales of months to years, with occasional wide-ranging use of the atoll. Diel variation in the number of detections received strongly suggest nocturnal resting. Long-term tracking data reveal 3 degrees of site fidelity across the atoll, based on the number of detection days near individual stations: high residency (n = 4 turtles), sequential residency (n = 5), and transient behavior (n = 4). These variations in movement raise questions about the differentiation of foraging habitats and degree of individual specialization within this population, as well as the influences of microhabitats and human disturbance.

show abstract

Section: Patterns Of Movementsupporting

confidence: 60%

Movement patterns of juvenile hawksbill turtles Eretmochelys imbricata at a Caribbean coral atoll: long-term tracking using passive acoustic telemetry

Chevis¹,

Godley²,

Lewis³

et al. 2017

Endang. Species. Res.

View full text Add to dashboard Cite

show abstract

“…From a conservation perspective, information on the sex ratio and source of local foraging aggregations is paramount, as individual nation-state management strategies (including consumptive use of marine turtles) could have implications beyond national boundaries (see Moncada et al 2012 for more detailed discussion). Primary sex ratios and molecular profiles for many Caribbean rookeries remain to be described and should be collected as a 16 Hawkes et al: Sex ratios in hawksbill turtles conservation priority.…”

Section: Foraging Stock Compositionmentioning

confidence: 99%

“…Genetic work and satellite tracking over the last 15 yr has demonstrated that hawksbill turtles sharing a Caribbean foraging site usually come from distant as well as local rookeries (Bass 1999, Diaz-Fernandez et al 1999, Horrocks et al 2001, Troëng et al 2005, Bowen et al 2007, Mortimer et al 2007, Van Dam et al 2008, Blumenthal et al 2009, Browne et al 2010, Meylan et al 2011, Moncada et al 2012. Initial haplotype data for Anegada suggests that the BVI foraging population consists of individuals from several different source rookeries throughout the Caribbean basin (Godley et al 2004), but enumerating the likely proportion of each would be an important demographic parameter for predictive models of climate change effects.…”

Section: Foraging Stock Compositionmentioning

confidence: 99%

“…International trade was once the major threat to hawksbill turtles, due to demand for 'tortoiseshell' products. Harvesting has now largely ceased but for a few Caribbean nations (Moncada et al 2012), including the British Virgin Islands (BVI), where they are still legally harvested for subsistence purposes (Richardson et al 2006). Approximately 25 to 75 hawksbill turtles nest in BVI annually, the majority on Anegada (Fletemeyer 1984, Hastings 1992, a remnant of a once larger population (McGowan et al 2008).…”

mentioning

confidence: 99%

“…Initial haplotype data for Anegada suggests that the BVI foraging population consists of individuals from several different source rookeries throughout the Caribbean basin (Godley et al 2004), but enumerating the likely proportion of each would be an important demographic parameter for predictive models of climate change effects. For example, such data could permit insights into potential sexbiased dispersal or mortality during the 'lost years' for which no data currently exist (see Witherington et al 2012).From a conservation perspective, information on the sex ratio and source of local foraging aggregations is paramount, as individual nation-state management strategies (including consumptive use of marine turtles) could have implications beyond national boundaries (see Moncada et al 2012 for more detailed discussion). Primary sex ratios and molecular profiles for many Caribbean rookeries remain to be described and should be collected as a 16 Hawkes et al: Sex ratios in hawksbill turtles conservation priority.…”

mentioning

confidence: 99%

See 2 more Smart Citations

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

Hawkes¹,

McGowan²,

Godley³

et al. 2013

Aquat. Biol.

View full text Add to dashboard Cite

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 con centrations 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. KEY WORDS: Marine turtles · Sex ratio · Climate change · HormonesResale or republication not permitted without written consent of the publisher Aquat Biol 18: 9-19, 2013 Skewed sex ratios may be advantageous under specific biological circumstances (e.g. if pa rental investment in the sexes is unequal, if one sex helps their parents or if male siblings compete for mates), but also in some environmental circumstances (Warner & Shine 2008). The Charnov-Bull model (Charnov & Bull 1977) was proposed to ex plain this and has been demonstrated for a lizard species, such that offspring raised in conditions that promote high fitness for females had higher lifetime reproductive success if they were female than male (males were produced by hormonal manipulation at temperatures that usually lead to the development of females; Warner & Shine 2008). Temperature-dependent sex determinationIn marine turtles, sex is determined by the temperature experienced during the middle third of the embryo incubation period (temperature-dependent sex determination [TSD], a type of ESD), where males are produced at lower temperatures and females at higher temperatures (Yntema & Mrosovsky 1980, 1982, Mrosovsky 1988. The majority of research into sex ratios of marine turtles has been carried out on the nesting beach at the hatchling stage, and approaches using the modelled relationship between incubation temperature and sex ratio, as well as incubation duration and sex ratio, have enabled estimation of 'primary' sex ratio for a large number of rookeries (reviewed in Hawkes et al. 2009). Primary sex ratios vary among beaches and within clutches, as well as during the course of a nest...

show abstract

Diverse migratory strategies for a hawksbill sea turtle population

Maurer,

Seminoff,

Burford Reiskind

et al. 2024

Aquatic Conservation

View full text Add to dashboard Cite

Outside of short, infrequent visits to reproductive habitats, sea turtle lifespans are largely spent in foraging areas. Supporting imperilled populations in an era of biodiversity declines and environmental change requires improvements in the understanding of foraging distributions, plus the migratory corridors that connect foraging and reproductive habitats. This study evaluates the migratory strategies and foraging geography of hawksbill sea turtles (Eretmochelys imbricata) in the Western Atlantic. The post‐nesting migrations of 22 females were tracked via satellite telemetry from Long Island, Antigua, during 2016–2019, and a state‐space model was utilized to estimate true turtle locations from Argos satellite fixes. Model output was used to characterize migratory routes and home ranges occupied during non‐migratory inter‐nesting and foraging periods. Hawksbill migrations (N = 19) resulted in displacements to foraging areas ranging 7–2300 km. Foraging geography varied considerably—whereas eight turtles remained in the immediate vicinity of Antigua and Barbuda (<30 km), there were also longer‐distance migrations (>470 km) to locations such as The Bahamas and Nicaragua. Inter‐nesting core home ranges (50% utilization distributions) ranged from 7 to 72 km2, while foraging core areas ranged from 7 to 46 km2. These results add to evidence suggesting that, broadly, post‐nesting hawksbills forage in neritic habitats throughout the Wider Caribbean, including several high‐use areas. Short displacements to foraging habitats relatively nearby to nesting beaches appear to be the most common migratory behaviour, but individuals in a single population may exhibit various migratory strategies, resulting in basin‐wide connectivity between nesting and foraging sites. Given that a single individual or nesting population may inhabit several management jurisdictions, an idealized scenario for regional hawksbill conservation would entail data sharing between managers at linked nesting areas, foraging habitats and migratory corridors such that policies to protect key habitats and mitigate human impacts are designed and evaluated based on best‐available science.

show abstract

Patterns of dispersal of hawksbill turtles from the Cuban shelf inform scale of conservation and management

Cited by 30 publications

References 45 publications

Movement patterns of juvenile hawksbill turtles Eretmochelys imbricata at a Caribbean coral atoll: long-term tracking using passive acoustic telemetry

Movement patterns of juvenile hawksbill turtles Eretmochelys imbricata at a Caribbean coral atoll: long-term tracking using passive acoustic telemetry

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

Diverse migratory strategies for a hawksbill sea turtle population

Contact Info

Product

Resources

About