Microclimate of American crocodile nests in Banco Chinchorro biosphere reserve, Mexico effect on incubation length, embryos survival and hatchlings sex

Crocodilians have temperature-dependent sex determination (TSD) in which incubation temperature determines sex of embryo. Global warming is expected to alter hatchling sex ratio, leading to the extinction of small populations. Regional climate influence on crocodile nest microclimate and hatchlings' characteristics is poorly known. Here, microclimate in natural nests of American crocodile (Crocodylus acutus) and its relation with incubation length, hatchling sex and nesting success was studied in Banco Chinchorro Biosphere Reserve (Mexico) from 2007 to 2010. Temperature and relative humidity in different locations within and outside the nests were registered by data loggers. Incident solar radiation above nest was calculated from hemispheric photographs. Incubation length, proportion of hatchling reaching complete development and hatchling sex were determined at hatching. Nest temperatures exhibited a cyclic daily fluctuation due to solar radiation, which is the major heat source for nests. Clutch temperature was relatively stable and its daily amplitude was negatively correlated with clutch depth and size. Rainfall was the major source of clutch temperature decrease. Clutch and metabolic temperatures increased significantly during incubation. A small sample size failed to demonstrate a statistical relationship between length of incubation and mean clutch temperature. Proportion of embryos reaching complete development depended on maximum and minimum clutch temperature, maximum daily amplitude of clutch temperature and maximum decrease in clutch temperature on a period ≤4 day. Results confirmed a Female-Male-Female TSD pattern for C. acutus, with 31 and 32.5 °C as possible pivotal temperatures. Population and hatchling sex ratios were male-biased and fate of crocodiles of Banco Chinchorro could depend on the magnitude of temperature increase in the future.

Saved in:
Bibliographic Details
Main Author: Charruau, Pierre Alexandre Rémy Robert Doctor autor/a 13179
Format: Texto biblioteca
Language:eng
Subjects:Crocodylus acutus, Incubación de huevos, Cambio climático, Reproducción animal, Artfrosur,
Tags: Add Tag
No Tags, Be the first to tag this record!
id KOHA-OAI-ECOSUR:5118
record_format koha
institution ECOSUR
collection Koha
country México
countrycode MX
component Bibliográfico
access En linea
databasecode cat-ecosur
tag biblioteca
region America del Norte
libraryname Sistema de Información Bibliotecario de ECOSUR (SIBE)
language eng
topic Crocodylus acutus
Incubación de huevos
Cambio climático
Reproducción animal
Artfrosur
Crocodylus acutus
Incubación de huevos
Cambio climático
Reproducción animal
Artfrosur
spellingShingle Crocodylus acutus
Incubación de huevos
Cambio climático
Reproducción animal
Artfrosur
Crocodylus acutus
Incubación de huevos
Cambio climático
Reproducción animal
Artfrosur
Charruau, Pierre Alexandre Rémy Robert Doctor autor/a 13179
Microclimate of American crocodile nests in Banco Chinchorro biosphere reserve, Mexico effect on incubation length, embryos survival and hatchlings sex
description Crocodilians have temperature-dependent sex determination (TSD) in which incubation temperature determines sex of embryo. Global warming is expected to alter hatchling sex ratio, leading to the extinction of small populations. Regional climate influence on crocodile nest microclimate and hatchlings' characteristics is poorly known. Here, microclimate in natural nests of American crocodile (Crocodylus acutus) and its relation with incubation length, hatchling sex and nesting success was studied in Banco Chinchorro Biosphere Reserve (Mexico) from 2007 to 2010. Temperature and relative humidity in different locations within and outside the nests were registered by data loggers. Incident solar radiation above nest was calculated from hemispheric photographs. Incubation length, proportion of hatchling reaching complete development and hatchling sex were determined at hatching. Nest temperatures exhibited a cyclic daily fluctuation due to solar radiation, which is the major heat source for nests. Clutch temperature was relatively stable and its daily amplitude was negatively correlated with clutch depth and size. Rainfall was the major source of clutch temperature decrease. Clutch and metabolic temperatures increased significantly during incubation. A small sample size failed to demonstrate a statistical relationship between length of incubation and mean clutch temperature. Proportion of embryos reaching complete development depended on maximum and minimum clutch temperature, maximum daily amplitude of clutch temperature and maximum decrease in clutch temperature on a period ≤4 day. Results confirmed a Female-Male-Female TSD pattern for C. acutus, with 31 and 32.5 °C as possible pivotal temperatures. Population and hatchling sex ratios were male-biased and fate of crocodiles of Banco Chinchorro could depend on the magnitude of temperature increase in the future.
format Texto
topic_facet Crocodylus acutus
Incubación de huevos
Cambio climático
Reproducción animal
Artfrosur
author Charruau, Pierre Alexandre Rémy Robert Doctor autor/a 13179
author_facet Charruau, Pierre Alexandre Rémy Robert Doctor autor/a 13179
author_sort Charruau, Pierre Alexandre Rémy Robert Doctor autor/a 13179
title Microclimate of American crocodile nests in Banco Chinchorro biosphere reserve, Mexico effect on incubation length, embryos survival and hatchlings sex
title_short Microclimate of American crocodile nests in Banco Chinchorro biosphere reserve, Mexico effect on incubation length, embryos survival and hatchlings sex
title_full Microclimate of American crocodile nests in Banco Chinchorro biosphere reserve, Mexico effect on incubation length, embryos survival and hatchlings sex
title_fullStr Microclimate of American crocodile nests in Banco Chinchorro biosphere reserve, Mexico effect on incubation length, embryos survival and hatchlings sex
title_full_unstemmed Microclimate of American crocodile nests in Banco Chinchorro biosphere reserve, Mexico effect on incubation length, embryos survival and hatchlings sex
title_sort microclimate of american crocodile nests in banco chinchorro biosphere reserve, mexico effect on incubation length, embryos survival and hatchlings sex
work_keys_str_mv AT charruaupierrealexandreremyrobertdoctorautora13179 microclimateofamericancrocodilenestsinbancochinchorrobiospherereservemexicoeffectonincubationlengthembryossurvivalandhatchlingssex
_version_ 1809098526288773120
spelling KOHA-OAI-ECOSUR:51182024-08-07T11:26:13ZMicroclimate of American crocodile nests in Banco Chinchorro biosphere reserve, Mexico effect on incubation length, embryos survival and hatchlings sex Charruau, Pierre Alexandre Rémy Robert Doctor autor/a 13179 textengCrocodilians have temperature-dependent sex determination (TSD) in which incubation temperature determines sex of embryo. Global warming is expected to alter hatchling sex ratio, leading to the extinction of small populations. Regional climate influence on crocodile nest microclimate and hatchlings' characteristics is poorly known. Here, microclimate in natural nests of American crocodile (Crocodylus acutus) and its relation with incubation length, hatchling sex and nesting success was studied in Banco Chinchorro Biosphere Reserve (Mexico) from 2007 to 2010. Temperature and relative humidity in different locations within and outside the nests were registered by data loggers. Incident solar radiation above nest was calculated from hemispheric photographs. Incubation length, proportion of hatchling reaching complete development and hatchling sex were determined at hatching. Nest temperatures exhibited a cyclic daily fluctuation due to solar radiation, which is the major heat source for nests. Clutch temperature was relatively stable and its daily amplitude was negatively correlated with clutch depth and size. Rainfall was the major source of clutch temperature decrease. Clutch and metabolic temperatures increased significantly during incubation. A small sample size failed to demonstrate a statistical relationship between length of incubation and mean clutch temperature. Proportion of embryos reaching complete development depended on maximum and minimum clutch temperature, maximum daily amplitude of clutch temperature and maximum decrease in clutch temperature on a period ≤4 day. Results confirmed a Female-Male-Female TSD pattern for C. acutus, with 31 and 32.5 °C as possible pivotal temperatures. Population and hatchling sex ratios were male-biased and fate of crocodiles of Banco Chinchorro could depend on the magnitude of temperature increase in the future.Crocodilians have temperature-dependent sex determination (TSD) in which incubation temperature determines sex of embryo. Global warming is expected to alter hatchling sex ratio, leading to the extinction of small populations. Regional climate influence on crocodile nest microclimate and hatchlings' characteristics is poorly known. Here, microclimate in natural nests of American crocodile (Crocodylus acutus) and its relation with incubation length, hatchling sex and nesting success was studied in Banco Chinchorro Biosphere Reserve (Mexico) from 2007 to 2010. Temperature and relative humidity in different locations within and outside the nests were registered by data loggers. Incident solar radiation above nest was calculated from hemispheric photographs. Incubation length, proportion of hatchling reaching complete development and hatchling sex were determined at hatching. Nest temperatures exhibited a cyclic daily fluctuation due to solar radiation, which is the major heat source for nests. Clutch temperature was relatively stable and its daily amplitude was negatively correlated with clutch depth and size. Rainfall was the major source of clutch temperature decrease. Clutch and metabolic temperatures increased significantly during incubation. A small sample size failed to demonstrate a statistical relationship between length of incubation and mean clutch temperature. Proportion of embryos reaching complete development depended on maximum and minimum clutch temperature, maximum daily amplitude of clutch temperature and maximum decrease in clutch temperature on a period ≤4 day. Results confirmed a Female-Male-Female TSD pattern for C. acutus, with 31 and 32.5 °C as possible pivotal temperatures. Population and hatchling sex ratios were male-biased and fate of crocodiles of Banco Chinchorro could depend on the magnitude of temperature increase in the future.Adobe Acrobat profesional 6.0 o superiorCrocodylus acutusIncubación de huevosCambio climáticoReproducción animalArtfrosurDisponible en líneaJournal of Thermal BiologyDisponible para usuarios de ECOSUR con su clave de acceso