Internesting intervals for loggerhead turtles, Caretta caretta, and green turtles, Chelonia mydas, are affected by temperature

1998 ◽  
Vol 76 (9) ◽  
pp. 1651-1662 ◽  
Author(s):  
Katsufumi Sato ◽  
Yoshimasa Matsuzawa ◽  
Hideji Tanaka ◽  
Takeharu Bando ◽  
Shingo Minamikawa ◽  
...  
Keyword(s):  
Body Temperature ◽  
Water Temperature ◽  
Clutch Size ◽  
Body Mass ◽  
Chelonia Mydas ◽  
Caretta Caretta ◽  
Mean Body Temperature ◽  
Green Turtles ◽  
Egg Maturation ◽  
Loggerhead Turtles

To investigate the influence of temperature on the length of internesting periods in loggerhead turtles (Caretta caretta) and green turtles (Chelonia mydas), body temperature and water temperature and depth for free-ranging turtles were monitored during internesting periods using micro data loggers. Body mass and clutch size were also measured. The experiments were conducted at nesting beaches in the Japanese archipelago from 1989 through 1996. Internesting interval was significantly negatively correlated with mean body temperature and mean water temperature. Internesting intervals for some turtles exceeded 21 d when they experienced low water temperatures. Arrhenius' equation was used to describe the quantitative relationships, and Q10 values of 3.1 for water temperature and 3.4 for body temperature were calculated. There was no significant relationship between either clutch size or body mass and internesting interval. Body temperatures were kept higher than water temperatures throughout internesting periods, and larger turtles showed a higher mean thermal difference between body temperature and water temperature. The internesting interval could be considered an egg-maturation period for the next oviposition. The rate of pre-ovipositional development of eggs seemed to be accelerated by high body temperature and decelerated by low body temperature.

Increase of sea turtles stranding records in Rhodes Island (eastern Mediterranean Sea): update of a long-term survey

2013 ◽  
Vol 93 (7) ◽  
pp. 1991-2002 ◽  
Author(s):  
Maria Corsini-Foka ◽  
Gerasimos Kondylatos ◽  
Elias Santorinios
Keyword(s):  
Eastern Mediterranean ◽  
Sea Turtles ◽  
Loggerhead Turtle ◽  
Aegean Sea ◽  
Chelonia Mydas ◽  
Caretta Caretta ◽  
Fishing Ground ◽  
Green Turtles ◽  
Loggerhead Turtles

A total of 209 strandings of sea turtles (152 loggerhead turtles Caretta caretta, 42 green turtles Chelonia mydas, 15 unidentified) were recorded during the period 1984–2011 along the coasts of Rhodes (Aegean Sea, Greece). The proportion of dead to live individuals was different in the two species. Stranded Caretta caretta were larger than Chelonia mydas. The size range of stranded green turtles, usually juveniles, appeared to increase since 2000, including the largest specimens ever observed in Greek waters. For both species, a tendency to strand more frequently on the west coast of the island, along fishing ground areas, was noted. The higher incidence of loggerhead turtle strandings was observed in summer, while more green turtle strandings were documented in winter. Factors involved in the increased trend of stranding records of both species, along with the acceleration of this phenomenon in the last decade, are discussed. Data from Rhodes provide evidence that human activities detrimentally affect mainly larger-sized loggerhead turtles living in shallow waters.

Internesting intervals for loggerhead turtles, Caretta caretta, and green turtles, Chelonia mydas, are affected by temperature

1998 ◽  
Vol 76 (9) ◽  
pp. 1651-1662 ◽  
Author(s):  
Katsufumi Sato ◽  
Yoshimasa Matsuzawa ◽  
Hideji Tanaka ◽  
Takeharu Bando ◽  
Shingo Minamikawa ◽  
...  
Keyword(s):  
Chelonia Mydas ◽  
Caretta Caretta ◽  
Green Turtles ◽  
Loggerhead Turtles

scholarly journals Dietary analysis of two sympatric marine turtle species in the eastern Mediterranean

2021 ◽  
Vol 168 (6) ◽  
Author(s):  
Josie L. Palmer ◽  
Damla Beton ◽  
Burak A. Çiçek ◽  
Sophie Davey ◽  
Emily M. Duncan ◽  
...  
Keyword(s):  
Green Turtle ◽  
Eastern Mediterranean ◽  
Chelonia Mydas ◽  
Marine Turtle ◽  
Dietary Analysis ◽  
Low Frequencies ◽  
Turtle Species ◽  
Dietary Shift ◽  
Green Turtles ◽  
Loggerhead Turtles

AbstractDietary studies provide key insights into threats and changes within ecosystems and subsequent impacts on focal species. Diet is particularly challenging to study within marine environments and therefore is often poorly understood. Here, we examined the diet of stranded and bycaught loggerhead (Caretta caretta) and green turtles (Chelonia mydas) in North Cyprus (35.33° N, 33.47° E) between 2011 and 2019. A total of 129 taxa were recorded in the diet of loggerhead turtles (n = 45), which were predominantly carnivorous (on average 72.1% of dietary biomass), foraging on a large variety of invertebrates, macroalgae, seagrasses and bony fish in low frequencies. Despite this opportunistic foraging strategy, one species was particularly dominant, the sponge Chondrosia reniformis (21.5%). Consumption of this sponge decreased with increasing turtle size. A greater degree of herbivory was found in green turtles (n = 40) which predominantly consumed seagrasses and macroalgae (88.8%) with a total of 101 taxa recorded. The most dominant species was a Lessepsian invasive seagrass, Halophila stipulacea (31.1%). This is the highest percentage recorded for this species in green turtle diet in the Mediterranean thus far. With increasing turtle size, the percentage of seagrass consumed increased with a concomitant decrease in macroalgae. Seagrass was consumed year-round. Omnivory occurred in all green turtle size classes but reduced in larger turtles (> 75 cm CCL) suggesting a slow ontogenetic dietary shift. Macroplastic ingestion was more common in green (31.6% of individuals) than loggerhead turtles (5.7%). This study provides the most complete dietary list for marine turtles in the eastern Mediterranean.

Clutch size for Mediterranean loggerhead turtles (Caretta caretta)

1992 ◽  
Vol 226 (2) ◽  
pp. 321-327 ◽  
Author(s):  
G. C. Hays ◽  
J. R. Speakman
Keyword(s):  
Clutch Size ◽  
Caretta Caretta ◽  
Loggerhead Turtles

scholarly journals Sea turtles in Lake Bardawil, Egypt - size distribution and population structure

2020 ◽  
pp. 32-36
Author(s):  
Basem Rabia
Keyword(s):  
Size Distribution ◽  
Narrow Range ◽  
Chelonia Mydas ◽  
Ratio And Proportion ◽  
Green Turtles ◽  
Loggerhead Turtles ◽  
Feeding Area ◽  
Development Area ◽  
Sexually Mature ◽  
The Mediterranean Basin

We investigated the size distribution, sex ratio, and proportion of sexually mature green (Chelonia mydas) and loggerhead (Caretta caretta) turtles in Lake Bardawil, a large coastal lagoon. During the study 30 green turtles (8 males, 4 females, and 18 juveniles / sub-adults) and 14 loggerheads (1 male, 8 females, and 5 sub-adults) were captured. Forty percent of the green and 64 % of loggerhead turtles were believed to be sexually mature. The green turtles had a mean curved carapace length of 65.23 cm (15 – 100 cm range) and the loggerhead turtles 68.79 cm but with a much narrow range (60 - 80 cm) reflecting the absence of juveniles. This study provides evidence that Lake Bardawil is an important feeding and development area for green turtles and feeding area for loggerhead turtles and expands our knowledge of such important sites in the Mediterranean basin.

Maintenance of neutral buoyancy by depth selection in the loggerhead turtle Caretta caretta

2000 ◽  
Vol 203 (19) ◽  
pp. 2967-2975 ◽  
Author(s):  
S. Minamikawa ◽  
Y. Naito ◽  
K. Sato ◽  
Y. Matsuzawa ◽  
T. Bando ◽  
...  
Keyword(s):  
Lung Volume ◽  
Time Series Data ◽  
Loggerhead Turtle ◽  
Caretta Caretta ◽  
Dive Depth ◽  
Dive Duration ◽  
Series Data ◽  
Neutral Buoyancy ◽  
Egg Maturation ◽  
Loggerhead Turtles

Time-series data of swimming speed and dive depth were recorded in six female loggerhead turtles Caretta caretta during the internesting period. The dive profiles of all animals indicated that they stayed at particular depths without swimming and that these depths were correlated with dive duration. These results support the hypothesis that lung air is used to achieve neutral buoyancy in the loggerhead turtle. To test this hypothesis, female turtles were equipped with lead weights and time/depth recorders. The residence depth of the turtles increased when their specific gravity was artificially decreased. This indicates that they control depth rather than lung volume, suggesting that the residence depth of loggerhead turtles during the internesting period is not determined actively. They presumably remain at a particular depth exclusively to save energy for egg maturation during the internesting period. Lung volume was estimated from the change in depth of weighted animals to be 50–150 ml kg(−1). The resulting residence depth of all turtles was within the range at which they maintained the neutral buoyancy.

scholarly journals Temperature of water ingested before exercise alters the onset of physiological heat loss responses

2019 ◽  
Vol 316 (1) ◽  
pp. R13-R20 ◽  
Author(s):  
Nathan B. Morris ◽  
Georgia K. Chaseling ◽  
Anthony R. Bain ◽  
Ollie Jay
Keyword(s):  
Blood Pressure ◽  
Blood Flow ◽  
Body Temperature ◽  
Relative Humidity ◽  
Body Mass ◽  
Sweat Rate ◽  
Vascular Conductance ◽  
Mean Body Temperature ◽  
Local Sweat Rate ◽  
Cutaneous Vascular Conductance

This study sought to determine whether the temperature of water ingested before exercise alters the onset threshold and subsequent thermosensitivity of local vasomotor and sudomotor responses after exercise begins. Twenty men [24 (SD 4) yr of age, 75.8 (SD 8.1) kg body mass, 52.3 (SD 7.7) ml·min−1·kg−1peak O2consumption (V̇o2peak)] ingested 1.5°C, 37°C, or 50°C water (3.2 ml/kg), rested for 5 min, and then cycled at 50% V̇o2peakfor 15 min at 23.0 (SD 0.9) °C and 32 (SD 10) % relative humidity. Mean body temperature (Tb), local sweat rate (LSR), and skin blood flow (SBF) were measured. In a subset of eight men [25 (SD 5) yr of age, 78.6 (SD 8.3) kg body mass, 48.9 (SD 11.1) ml·min−1·kg−1V̇o2peak], blood pressure was measured and cutaneous vascular conductance (CVC) was determined. The change in Tbwas greater at the onset of LSR measurement with ingestion of 1.5°C than 50°C water [ΔTb= 0.19 (SD 0.15) vs. 0.11 (SD 0.12) °C, P = 0.04], but not 37°C water [ΔTb= 0.14 (SD 0.14) °C, P = 0.23], but did not differ between trials for SBF measurement [ΔTb= 0.18 (SD 0.15) °C, 0.11 (SD 0.13) °C, and 0.09 (SD 0.09) °C with 1.5°C, 37°C, and 50°C water, respectively, P = 0.07]. Conversely, the thermosensitivity of LSR and SBF was not different [LSR = 1.11 (SD 0.75), 1.11 (SD 0.75), and 1.34 (SD 1.11) mg·min−1·cm−2·°C−1with 1.5°C, 37°C, and 50°C ingested water, respectively ( P = 0.46); SBF = 717 (SD 882), 517 (SD 606), and 857 (SD 904) %baseline arbitrary units (AU)/°C with 1.5°C, 37°C, and 50°C ingested water, respectively ( P = 0.95)]. After 15 min of exercise, LSR and SBF were greater with ingestion of 50°C than 1.5°C water [LSR = 0.40 (SD 0.17) vs. 0.31 (SD 0.19) mg·min−1·cm−2( P = 0.02); SBF = 407 (SD 149) vs. 279 (SD 117) %baseline AU ( P < 0.001)], but not 37°C water [LSR = 0.50 (SD 0.22) mg·min−1·cm−2; SBF = 324 (SD 169) %baseline AU]. CVC was statistically unaffected [275 (SD 81), 340 (SD 114), and 384 (SD 160) %baseline CVC with 1.5°C, 37°C, and 50°C ingested water, respectively, P = 0.30]. Collectively, these results support the concept that visceral thermoreceptors modify the central drive for thermoeffector responses.

scholarly journals Spirorchiidiasis in stranded loggerhead Caretta caretta and green turtles Chelonia mydas in Florida (USA): host pathology and significance

2010 ◽  
Vol 89 ◽  
pp. 237-259 ◽  
Author(s):  
BA Stacy ◽  
AM Foley ◽  
E Greiner ◽  
LH Herbst ◽  
A Bolten ◽  
...  
Keyword(s):  
Chelonia Mydas ◽  
Caretta Caretta ◽  
Green Turtles

Body temperature independence of solar radiation in free-ranging loggerhead turtles, Caretta caretta, during internesting periods

1995 ◽  
Vol 123 (2) ◽  
pp. 197-205 ◽  
Author(s):  
Katsufumi Sato ◽  
Wataru Sakamoto ◽  
Yoshimasa Matsuzawa ◽  
Hideji Tanaka ◽  
Shingo Minamikawa ◽  
...  
Keyword(s):  
Body Temperature ◽  
Solar Radiation ◽  
Caretta Caretta ◽  
Loggerhead Turtles ◽  
Free Ranging

How influential are squamate reptile traits in explaining population responses to environmental disturbances?

2020 ◽  
Vol 47 (3) ◽  
pp. 249
Author(s):  
Yang Hu ◽  
Tim S. Doherty ◽  
Tim S. Jessop
Keyword(s):  
Body Size ◽  
Body Temperature ◽  
Clutch Size ◽  
Random Effects ◽  
Animal Species ◽  
Species Traits ◽  
Body Temperatures ◽  
Mean Body Temperature ◽  
Squamate Reptiles ◽  
Ecological Disturbances

Abstract Context Understanding how organismal attributes influence sensitivity to environmental perturbations is a central theme in ecology and conservation. Certain traits, such as body size, habitat use, dietary preference and reproductive output are considered important determinants of animal species’ responses to the impacts of ecological disturbances. However, the general relationships between functional traits and post-disturbance responses by animals are not fully understood. AimsOur primary aim was to use a meta-analysis to evaluate the influence of species traits on variation in population abundances of squamate reptiles (i.e. lizards and snakes). MethodsWe extracted data from 107 original published studies, from which 1027 mean effect sizes of post-disturbance responses by 298 species were estimated. We examined short-term responses only (i.e. within 3 years since the most recent disturbance). A comprehensive range of disturbances was examined, such as habitat destruction, fragmentation, fire, and exotic-species invasions. We used Bayesian linear mixed-effect modelling (BLMM), utilising the Markov-chain Monte Carlo algorithm (MCMC) for the meta-regression. Specifically, we tested the influence of eight species traits (body size, diet, temporal activity pattern, sociality, reproductive mode, clutch size, habitat selection, and mean body temperature), along with disturbance type, in explaining variation in species-specific abundance responses of squamate reptiles post-disturbance. Key resultsPost-disturbance abundance responses of squamate species were significantly influenced by two parameters, namely, mean body temperature and clutch size. In general, significant positive responses post-disturbance were observed for species with higher mean body temperatures and a greater clutch size. The type of disturbance had no detectable influence on squamate abundances. The influence of random effects (heterogeneity among studies and species, and broad taxonomic identity) accounted for more of the model variation than did the fixed effects (species traits and disturbance type). ConclusionsCertain species traits exerted some influence on the sensitivities of lizards and snakes to ecological disturbances, although the influence of random effects was very strong. Our findings are likely to be a result of the complexity and idiosyncratic nature of natural abundance patterns among animal species, in addition to the potential confounding effect of methodological differences among studies. ImplicationsThe present study is the first major quantitative synthesis of how species traits influence population-level responses of squamate reptiles to ecological disturbances. The findings can be used to guide conservation efforts and ecological management, such as by prioritising the efforts of mitigation on species that reproduce more slowly, and those with lower body temperatures.

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