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1.
Glob Chang Biol ; 30(1): e16991, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37905464

ABSTRACT

Sea turtles are vulnerable to climate change since their reproductive output is influenced by incubating temperatures, with warmer temperatures causing lower hatching success and increased feminization of embryos. Their ability to cope with projected increases in ambient temperatures will depend on their capacity to adapt to shifts in climatic regimes. Here, we assessed the extent to which phenological shifts could mitigate impacts from increases in ambient temperatures (from 1.5 to 3°C in air temperatures and from 1.4 to 2.3°C in sea surface temperatures by 2100 at our sites) on four species of sea turtles, under a "middle of the road" scenario (SSP2-4.5). Sand temperatures at sea turtle nesting sites are projected to increase from 0.58 to 4.17°C by 2100 and expected shifts in nesting of 26-43 days earlier will not be sufficient to maintain current incubation temperatures at 7 (29%) of our sites, hatching success rates at 10 (42%) of our sites, with current trends in hatchling sex ratio being able to be maintained at half of the sites. We also calculated the phenological shifts that would be required (both backward for an earlier shift in nesting and forward for a later shift) to keep up with present-day incubation temperatures, hatching success rates, and sex ratios. The required shifts backward in nesting for incubation temperatures ranged from -20 to -191 days, whereas the required shifts forward ranged from +54 to +180 days. However, for half of the sites, no matter the shift the median incubation temperature will always be warmer than the 75th percentile of current ranges. Given that phenological shifts will not be able to ameliorate predicted changes in temperature, hatching success and sex ratio at most sites, turtles may need to use other adaptive responses and/or there is the need to enhance sea turtle resilience to climate warming.


Subject(s)
Turtles , Animals , Turtles/physiology , Temperature , Climate Change , Reproduction , Sex Ratio
2.
Am J Orthopsychiatry ; 90(2): 267-282, 2020.
Article in English | MEDLINE | ID: mdl-32105125

ABSTRACT

Despite the proclamation of a "postracial" society, racism in the United States remains "alive and sick" (S. P. Harrell, 2000), negatively impacting the physical, psychological, and emotional well-being of Black Americans. Moreover, the complex impact of racism throughout the life span is inadequately understood. Coping with the insidiousness of racism in its myriad forms requires recognizing how it expresses across development. In this developmental overview, we apply a life-course perspective (Gee, Walsemann, & Brondolo, 2012) to investigate racism-related stress and coping over time. Within each period of development, we first explore how racism-related stress may present for Black Americans and then document what coping from this stress looks like, highlighting extant strategies and interventions where they exist. This work concludes with a set of definitional, methodological, and clinical future directions and recommendations for improving the field's ability to mitigate the deleterious impact of racism-related stress. (PsycINFO Database Record (c) 2020 APA, all rights reserved).


Subject(s)
Adaptation, Psychological , Black or African American/psychology , Human Development , Racism/psychology , Stress, Psychological/ethnology , Adult , Aged , Child , Humans , United States/ethnology
3.
Conserv Biol ; 32(2): 390-400, 2018 04.
Article in English | MEDLINE | ID: mdl-28815792

ABSTRACT

Unsustainable wildlife trade affects biodiversity and the livelihoods of communities dependent upon those resources. Wildlife farming has been proposed to promote sustainable trade, but characterizing markets and understanding consumer behavior remain neglected but essential steps in the design and evaluation of such operations. We used sea turtle trade in the Cayman Islands, where turtles have been farm raised for human consumption for almost 50 years, as a case study to explore consumer preferences toward wild-sourced (illegal) and farmed (legal) products and potential conservation implications. Combining methods innovatively (including indirect questioning and choice experiments), we conducted a nationwide trade assessment through in-person interviews from September to December 2014. Households were randomly selected using disproportionate stratified sampling, and responses were weighted based on district population size. We approached 597 individuals, of which 37 (6.2%) refused to participate. Although 30% of households had consumed turtle in the previous 12 months, the purchase and consumption of wild products was rare (e.g., 64-742 resident households consumed wild turtle meat [i.e., 0.3-3.5% of households] but represented a large threat to wild turtles in the area due to their reduced populations). Differences among groups of consumers were marked, as identified through choice experiments, and price and source of product played important roles in their decisions. Despite the long-term practice of farming turtles, 13.5% of consumers showed a strong preference for wild products, which demonstrates the limitations of wildlife farming as a single tool for sustainable wildlife trade. By using a combination of indirect questioning, choice experiments, and sales data to investigate demand for wildlife products, we obtained insights about consumer behavior that can be used to develop conservation-demand-focused initiatives. Lack of data from long-term social-ecological assessments hinders the evaluation of and learning from wildlife farming. This information is key to understanding under which conditions different interventions (e.g., bans, wildlife farming, social marketing) are likely to succeed.


Subject(s)
Conservation of Natural Resources , Consumer Behavior , Agriculture , Animals , Animals, Wild , Commerce , Farms , Humans
4.
Aliment Pharmacol Ther ; 45(12): 1534-1541, 2017 06.
Article in English | MEDLINE | ID: mdl-28449214

ABSTRACT

BACKGROUND: The incidence of paediatric inflammatory bowel disease diagnosed before age 10 years is reportedly increasing, but national data are limited. AIM: To characterise the epidemiology, phenotype and clinical outcomes of children diagnosed with inflammatory bowel disease before age 10 years, and compare with data from children diagnosed aged 10-16 years. METHODS: A review of all Irish cases of early onset inflammatory bowel disease (diagnosis <10 years, EO-IBD) presenting between January 2000 and December 2014 was undertaken and compared to a cohort of later onset paediatric inflammatory bowel disease patients (diagnosis between 10 and 16 years, LO-IBD). Diagnostic investigations, phenotype, treatments, and long-term clinical and surgical outcomes were analysed. RESULTS: One hundred and ninety children (99 male) with EO-IBD were identified; 92 (48%) CD, 77 (41%) UC and 21 (11%) IBDU. The incidence of EO-IBD increased by 0.6 per 100 000 per year (0.8-3.2 per 100 000 per year), with a significant increase in UC by 0.06 per 100 000 per year (P=.02). Males with CD had more upper GI disease (L4a; 48% vs 21%; P=.007), more extensive disease distribution (L3±L4; 31% vs 11%; P=.05) and more severe disease activity at presentation (52% vs 31%; P=.05) than females. Fewer patients with early onset than later onset Crohn's disease had ileocolonic disease (L3; 10% vs 20%; P<.001). More relapses were observed in the first year post-diagnosis in early onset than later onset IBD (1.02 vs 0.5 mean relapses; P<.001). CONCLUSIONS: EO-IBD is increasing in incidence. Males have more extensive and severe disease phenotypes, and younger patients have higher relapse rates than older children. Further research to explain these findings is warranted.


Subject(s)
Inflammatory Bowel Diseases/diagnosis , Inflammatory Bowel Diseases/epidemiology , Adolescent , Age of Onset , Child , Child, Preschool , Colitis, Ulcerative/diagnosis , Colitis, Ulcerative/epidemiology , Crohn Disease/diagnosis , Crohn Disease/epidemiology , Female , Humans , Incidence , Infant , Male , Prognosis , Recurrence , Sex Factors
5.
Ir Med J ; 110(10): 659, 2017 Dec 18.
Article in English | MEDLINE | ID: mdl-29465849

ABSTRACT

Malaria is the most serious parasitic infection. At our institution over a two year period there were treatment errors in 18% (n=3) of cases. The aim of this multidisciplinary study was to ensure appropriate and timely treatment of malaria by implementation of a cluster of interventions: reconfiguration of existing guidelines, provision of prescribing information; delivery of education sessions to front-line staff and enabling rapid access to medication. Staff feedback was assessed through a questionnaire. Perceived benefits gained included awareness of guidelines (91%, n= 39), how to diagnose (81%, n =35), how to treat (86%, n=37), that treatment must be prompt (77%, n=33) and where to find treatment out of hours (84%, n=36). 'Others' perceived benefits (5% n= 2) noted referred to treatment in pregnancy. Going forward, a programme of on-going staff education, repeated audits of guideline compliance and promotion of reporting of medication errors should help ensure that these benefits are sustained.


Subject(s)
Malaria/drug therapy , Medication Errors , Female , Guideline Adherence , Hospitals, Teaching , Humans , Ireland , Personnel, Hospital/education , Pregnancy , Pregnancy Complications, Infectious/drug therapy
6.
Ir J Med Sci ; 186(2): 339-343, 2017 May.
Article in English | MEDLINE | ID: mdl-26926524

ABSTRACT

BACKGROUND: Post-transplant lymphoproliferative disease (PTLD) is a serious complication of both solid organ and haematopoietic stem cell transplantation in children. Its incidence has increased over the last decade as a result of more potent immunosuppressive regimens. Many treatments have been explored however optimal therapy remains controversial. AIMS: We report on the diagnosis, treatment and outcome of ten patients who were diagnosed with PTLD in Our Lady's Hospital for Sick Children in Dublin between 2004 and 2015 inclusive. METHODS: Data were collected by retrospective review of patient medical records. RESULTS: 9 out of ten of our patients are alive and disease free following treatment for PTLD with rituximab alone or in combination with chemotherapy. CONCLUSION: The outcome of paediatric patients treated for PTLD at our institution is at least comparable to published international series and supports the use of rituximab ± low dose chemotherapy in the treatment of this malignancy.


Subject(s)
Hematopoietic Stem Cell Transplantation , Immunosuppressive Agents/therapeutic use , Lymphoproliferative Disorders/epidemiology , Organ Transplantation , Child , Child, Preschool , Female , Humans , Incidence , Infant , Male , Retrospective Studies , Rituximab/administration & dosage
9.
Anaesthesia ; 70(10): 1165-70, 2015 Oct.
Article in English | MEDLINE | ID: mdl-26074070

ABSTRACT

We undertook the first clinical evaluation of a novel, non-invasive device for the continuous measurement of plasma haemoglobin concentration in 25 patients undergoing elective cardiac surgery. At four pre-determined intervals, samples of blood were taken for plasma haemoglobin estimation on a blood gas analyser and a laboratory device and were compared with the plasma haemoglobin estimation on the novel device using the Bland-Altman method. The 95% limits of agreement for estimation of plasma haemoglobin concentration for the device vs. laboratory, the device vs. the blood gas analyser and the blood gas analyser vs. the laboratory were 101.3 g.l(-1) , 103.1 g.l(-1) and 14.5 g.l(-1) , respectively. The bias (mean difference) in each case was 27.4 g.l(-1) , 25.1 g.l(-1) and 2.4 g.l(-1) , respectively. We conclude that the novel device in its current form is not a suitable replacement for more invasive methods of determining plasma haemoglobin concentration in patients in the setting of cardiac surgery; however, lessons learnt from the study will help to improve the device's future performance.


Subject(s)
Cardiac Surgical Procedures , Hemoglobinometry/instrumentation , Monitoring, Intraoperative/instrumentation , Adult , Aged , Aged, 80 and over , Blood Gas Analysis/methods , Cardiopulmonary Bypass , Female , Hemoglobinometry/methods , Hemoglobins/metabolism , Humans , Male , Middle Aged , Monitoring, Intraoperative/methods , Reproducibility of Results
11.
Physiol Biochem Zool ; 87(6): 796-804, 2014.
Article in English | MEDLINE | ID: mdl-25461644

ABSTRACT

Temperature can have a profound effect on the phenotype of reptilian offspring, yet the bulk of current research considers the effects of constant incubation temperatures on offspring morphology, with few studies examining the natural thermal variance that occurs in the wild. Over two consecutive nesting seasons, we placed temperature data loggers in 57 naturally incubating clutches of loggerhead sea turtles Caretta caretta and found that greater diel thermal variance during incubation significantly reduced offspring mass, potentially reducing survival of hatchlings during their journey from the nest to offshore waters and beyond. With predicted scenarios of climate change, behavioral plasticity in nest site selection may be key for the survival of ectothermic species, particularly those with temperature-dependent sex determination.


Subject(s)
Temperature , Turtles/physiology , Animals , Cyprus , Female , Nesting Behavior , Oviposition , Phenotype
12.
Behav Sci (Basel) ; 4(2): 102-124, 2014 Jun.
Article in English | MEDLINE | ID: mdl-25379272

ABSTRACT

Posttraumatic stress disorder (PTSD) is a highly disabling disorder, afflicting African Americans at disproportionately higher rates than the general population. When receiving treatment, African Americans may feel differently towards a European American clinician due to cultural mistrust. Furthermore, racism and discrimination experienced before or during the traumatic event may compound posttrauma reactions, impacting the severity of symptoms. Failure to adapt treatment approaches to encompass cultural differences and racism-related traumas may decrease treatment success for African American clients. Cognitive behavioral treatment approaches are highly effective, and Prolonged Exposure (PE) in particular has the most empirical support for the treatment of PTSD. This article discusses culturally-informed adaptations of PE that incorporates race-related trauma themes specific to the Black experience. These include adding more sessions at the front end to better establish rapport, asking directly about race-related themes during the assessment process, and deliberately bringing to the forefront race-related experiences and discrimination during treatment when indicated. Guidelines for assessment and the development of appropriate exposures are provided. Case examples are presented demonstrating adaptation of PE for a survivor of race-related trauma and for a woman who developed internalized racism following a sexual assault. Both individuals experienced improvement in their posttrauma reactions using culturally-informed adaptations to PE.

13.
Proc Biol Sci ; 281(1780): 20133065, 2014 Apr 07.
Article in English | MEDLINE | ID: mdl-24523271

ABSTRACT

Large oceanic migrants play important roles in ecosystems, yet many species are of conservation concern as a result of anthropogenic threats, of which incidental capture by fisheries is frequently identified. The last large populations of the leatherback turtle, Dermochelys coriacea, occur in the Atlantic Ocean, but interactions with industrial fisheries could jeopardize recent positive population trends, making bycatch mitigation a priority. Here, we perform the first pan-Atlantic analysis of spatio-temporal distribution of the leatherback turtle and ascertain overlap with longline fishing effort. Data suggest that the Atlantic probably consists of two regional management units: northern and southern (the latter including turtles breeding in South Africa). Although turtles and fisheries show highly diverse distributions, we highlight nine areas of high susceptibility to potential bycatch (four in the northern Atlantic and five in the southern/equatorial Atlantic) that are worthy of further targeted investigation and mitigation. These are reinforced by reports of leatherback bycatch at eight of these sites. International collaborative efforts are needed, especially from nations hosting regions where susceptibility to bycatch is likely to be high within their exclusive economic zone (northern Atlantic: Cape Verde, Gambia, Guinea Bissau, Mauritania, Senegal, Spain, USA and Western Sahara; southern Atlantic: Angola, Brazil, Namibia and UK) and from nations fishing in these high-susceptibility areas, including those located in international waters.


Subject(s)
Animal Migration , Fisheries , Turtles/physiology , Animals , Atlantic Ocean , Conservation of Natural Resources , Ecosystem , Population Density , Population Dynamics
14.
Acta Biomater ; 9(2): 5040-51, 2013 Feb.
Article in English | MEDLINE | ID: mdl-23069317

ABSTRACT

A major focus in the field of tissue engineering is the regulation of essential cell behaviors through biophysical and biochemical cues from the local extracellular environment. The impact of nanotopographical cues on human corneal epithelial cell (HCEC) contact guidance, proliferation, migration and adhesion have previously been demonstrated. In the current report we have expanded our study of HCEC responses to include both biophysical and controlled biochemical extracellular cues. By exploiting methods for the layer-by-layer coating of substrates with reactive poly(ethylene imine)/poly(2-vinyl-4,4-dimethylazlactone)-based multilayer thin films we have incorporated a single adhesion peptide motif, Arg-Gly-Asp (RGD), on topographically patterned substrates. This strategy eliminates protein adsorption onto the surface, thus decoupling the effects of the HCEC response to topographical cues from adsorbed proteins and soluble media proteins. The direction of cell alignment was dependent on the scale of the topographical cues and, to less of an extent, the culture medium. In EpiLife® medium cell alignment to unmodified-NOA81 topographical features, which allowed protein adsorption, differed significantly from cell alignment on RGD-modified features. These results demonstrate that the surface chemical composition significantly affects how HCECs respond to topographical cues. In summary, we have demonstrated modulation of the HCEC response to environmental cues through critical substrate and soluble parameters.


Subject(s)
Biomimetic Materials/chemistry , Biomimetic Materials/pharmacology , Cell Communication/drug effects , Epithelial Cells/cytology , Epithelium, Corneal/cytology , Extracellular Matrix/chemistry , Oligopeptides/pharmacology , Amino Acid Sequence , Cell Adhesion/drug effects , Culture Media/pharmacology , Epithelial Cells/drug effects , Humans , Imines/chemistry , Imines/pharmacology , Lactones/chemistry , Lactones/pharmacology , Molecular Sequence Data , Polyethylenes/chemistry , Polyethylenes/pharmacology , Polyvinyls/chemistry , Polyvinyls/pharmacology , Reproducibility of Results
15.
Neurogastroenterol Motil ; 24(10): 922-7, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22762244

ABSTRACT

BACKGROUND: Cyclical vomiting syndrome (CVS) is a disorder that affects all ages and is characterized by episodes of severe nausea and vomiting with symptom-free intervals between episodes. The incidence in children is 3.15/100 000 children per year. Our objective was to evaluate the natural history of CVS and examine factors that predict symptom resolution. METHODS: Thirty newly diagnosed children (mean 9.15 years, SD 3.31 range 3.5-15.7) were enrolled. All children had a follow-up interview at 3 months, 27/30 at 6 months, and 22/30 at 9 months. KEY RESULTS: Following diagnosis of CVS, only 5/22(22.7%) children had no further episodes of vomiting at 9 months, whereas 17/22 (77.3%) continued to vomit. In the year prior to diagnosis, 15/30 (50%) children were admitted to hospital. Of the 22 children with follow-up for 9 months, only one child required hospital admission. Children who continued to vomit had higher internalizing scores on CBCL compared with those who stopped vomiting (P = NS). The Pediatric Quality-of-Life Score suggested those who continued to vomit had a poorer quality of life at diagnosis compared with those who stopped vomiting (P < 0.05). CONCLUSIONS & INFERENCES: Making a positive diagnosis of CVS and providing families with information is very important in the management of CVS. Although 75% of children reported regular episodes of vomiting 9 months after diagnosis, there was a significant reduction in the frequency and severity of symptoms in addition to a marked reduction in the use of medical services.


Subject(s)
Vomiting/diagnosis , Vomiting/epidemiology , Adolescent , Child , Child, Preschool , Female , Humans , Male , Periodicity , Prospective Studies , Quality of Life , Syndrome
16.
Arch Dis Child ; 97(7): 590-4, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22550323

ABSTRACT

AIMS: To describe the change in incidence of paediatric inflammatory bowel disease (IBD) observed at the National Centre for Paediatric Gastroenterology, Hepatology and Nutrition, and to determine whether the presenting disease phenotype and disease outcomes have changed during the past decade. METHODS: The annual incidence of IBD in Irish children aged <16 years was calculated for the years 2000-2010. Two subsets of patients, group A (diagnosed between 1 January 2000 and 31 December 2001), and group B (diagnosed between 1 January and 31 December 2008) were phenotyped according to the Paris Classification. Phenotype at diagnosis and 2-year follow-up were then compared. RESULTS: 406 new cases of IBD were identified. The incidence was 2.5/100 000/year in 2001, 7.3 in 2008 and 5.6 in 2010, representing a significant increase in the number of new cases of Crohn's disease (CD) and ulcerative colitis (UC). There were 238 cases of CD; 129 of UC; and 39 of IBD unclassified. Comparing groups A and B, no differences were found in disease location at diagnosis or, for CD, in its behaviour. CONCLUSIONS: There has been a substantial and sustained increase in the incidence of childhood UC and CD in Ireland over a relatively short period of time. However, disease phenotype at diagnosis has not changed. At 2 years follow-up, CD appears to progress less frequently than in some neighbouring countries. These variations remain unexplained. Prospective longitudinal studies will help to elucidate further the epidemiology of childhood IBD.


Subject(s)
Inflammatory Bowel Diseases/epidemiology , Adolescent , Child , Child, Preschool , Colitis, Ulcerative/epidemiology , Colitis, Ulcerative/pathology , Colitis, Ulcerative/therapy , Crohn Disease/epidemiology , Crohn Disease/pathology , Crohn Disease/therapy , Disease Progression , Female , Humans , Incidence , Inflammatory Bowel Diseases/pathology , Inflammatory Bowel Diseases/therapy , Ireland/epidemiology , Male , Phenotype , Severity of Illness Index , Treatment Outcome
17.
Philos Trans A Math Phys Eng Sci ; 370(1959): 502-29, 2012 Jan 28.
Article in English | MEDLINE | ID: mdl-22184674

ABSTRACT

Marine renewable energy installations harnessing energy from wind, wave and tidal resources are likely to become a large part of the future energy mix worldwide. The potential to gather energy from waves has recently seen increasing interest, with pilot developments in several nations. Although technology to harness wave energy lags behind that of wind and tidal generation, it has the potential to contribute significantly to energy production. As wave energy technology matures and becomes more widespread, it is likely to result in further transformation of our coastal seas. Such changes are accompanied by uncertainty regarding their impacts on biodiversity. To date, impacts have not been assessed, as wave energy converters have yet to be fully developed. Therefore, there is a pressing need to build a framework of understanding regarding the potential impacts of these technologies, underpinned by methodologies that are transferable and scalable across sites to facilitate formal meta-analysis. We first review the potential positive and negative effects of wave energy generation, and then, with specific reference to our work at the Wave Hub (a wave energy test site in southwest England, UK), we set out the methodological approaches needed to assess possible effects of wave energy on biodiversity. We highlight the need for national and international research clusters to accelerate the implementation of wave energy, within a coherent understanding of potential effects-both positive and negative.


Subject(s)
Biodiversity , Marine Biology , Animals , United Kingdom
18.
Eur Arch Paediatr Dent ; 12(3): 167-9, 2011 Jun.
Article in English | MEDLINE | ID: mdl-21640063

ABSTRACT

AIM: To describe the outcome for children with oral Crohn's disease (OCD) at diagnosis, and to determine if there was a difference in the Paediatric Crohn's Disease Activity Index (PCDAI) scores between those with and those without oral lesions at follow-up. METHODS: Thirty-one patients with OCD who had enrolled in two previous studies were invited to participate. Clinical and laboratory data were collected to calculate the PCDAI. Details of the management of Crohn's disease were also recorded. RESULTS: Twenty-four of 31 patients participated (77%), of whom 17 were boys (M:F = 2.4:1). Mean age at follow-up was 15.7 years (SD 1.98, range 11.9-19.7 years). Mean duration of follow-up was 55 months (SD 22, range 20-97 months). Oral manifestations were present at follow-up in 7 (29%) of 24 patients. There were no differences between patients with and without OCD at follow-up with regard to medical treatments received or intestinal disease location. There was no difference in median PCDAI scores between those who had and those who had not oral lesions at follow-up. CONCLUSIONS: OCD resolved in the majority of children treated for intestinal Crohn's disease. The occurrence of mouth lesions during follow-up of children who had oral manifestations at initial diagnosis was not a marker for Crohn's disease activity elsewhere in the intestinal tract.


Subject(s)
Crohn Disease/complications , Mouth Diseases/etiology , Adolescent , Female , Follow-Up Studies , Humans , Male , Mouth Diseases/therapy , Severity of Illness Index , Treatment Outcome , Young Adult
19.
J Exp Biol ; 213(6): 901-11, 2010 Mar 15.
Article in English | MEDLINE | ID: mdl-20190115

ABSTRACT

Marine turtles utilise terrestrial and marine habitats and several aspects of their life history are tied to environmental features that are altering due to rapid climate change. We overview the likely impacts of climate change on the biology of these species, which are likely centred upon the thermal ecology of this taxonomic group. Then, focusing in detail on three decades of research on the loggerhead turtle (Caretta caretta L.), we describe how much progress has been made to date and how future experimental and ecological focus should be directed. Key questions include: what are the current hatchling sex ratios from which to measure future climate-induced changes? What are wild adult sex ratios and how many males are necessary to maintain a fertile and productive population? How will climate change affect turtles in terms of their distribution?


Subject(s)
Climate Change , Ecosystem , Seawater , Turtles , Animal Migration , Animals , Female , Male , Marine Biology , Nesting Behavior/physiology , Reproduction/physiology , Sex Ratio , Sexual Behavior, Animal/physiology , Temperature , Turtles/physiology
20.
Conserv Biol ; 24(1): 226-35, 2010 Feb.
Article in English | MEDLINE | ID: mdl-19723137

ABSTRACT

Where mechanisms inherent within the biology of a species affect individual fitness at low density, demographic-scale depensation may occur, hastening further decline and leading ultimately to population extirpation and species extinction. Reduction in fertility at low population densities has been identified in marine and terrestrial species. Using data on hatch success and hatchling-emergence success as proxies for fertilization success, we conducted a global meta-analysis of data from breeding aggregations of green turtles (Chelonia mydas) and loggerhead turtles (Caretta caretta). We found that there has been no reduction in fertility in small nesting aggregations in either of these species worldwide. We considered mechanisms within the mating strategies and reproductive biology of marine turtles that may allow for novel genetic input and facilitate enhanced gene flow among rookeries. Behavioral reproductive mechanisms, such as natal philopatry and polyandry, may mitigate potential impacts of depensation and contribute to the resilience of these species.


Subject(s)
Breeding , Marine Biology , Turtles/physiology , Animals , Female , Male , Sexual Behavior, Animal
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