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We examined the probability of past sea turtle nesting as a function of light intensity and patterns of temporal changes of light along nesting beaches in the Egyptian Red Sea. Beaches had a lower probability of past sea turtle nesting as light intensity increased. Light has been significantly increasing on mainland nesting beaches between 1992 and 2021 except for temporary declines. Island beaches historically had lower light pollution, but there was a sudden increase of light starting in 2014 that continued through 2021, except for the precipitous decline in 2020 during the Covid 19 pandemic. Light pollution on past nesting beaches has now approached levels that may be too polluted and discourage nesting. The impacts of the increased light pollution on nesting density and hatchling survival of hawksbill, Eretmochelys imbricata, and green turtles, Chelonia mydas, is likely negative., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Studies of feeding grounds are vital to understanding the ecology and conservation issues of sea turtles. The hypersaline, lake Bardawil, of North Sinai has recently been recognized as being a major feeding ground for sea turtles in the Mediterranean Sea. The objective of this research was to examine if the environmental variables (salinity, dissolved oxygen, and depth), distance to nearest Mediterranean inlet, and food availability (zooplankton and phytoplankton density) differed between areas according to species richness (green (Chelonia mydas) and loggerhead (Caretta caretta) turtles, single species, no species) and between areas in which loggerhead and green turtles were observed and not observed. Our results highlight the importance of environmental factors determining the distribution of endangered sea turtles as areas with high sea turtle richness had lower salinity, higher dissolved oxygen, were deeper and located closer to the nearest Mediterranean inlet. Our results support the suggestion that since the creation of the man-made inlets from the Mediterranean Sea, the environmental conditions of the hypersaline lake Bardawil have become less severe and more suitable for sea turtles as a feeding ground. The conservation of this biologically valuable lake will require active management to protect it from the increasing anthropogenic threats that will encroach upon the lake in the next decade. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Dispersal away from the release site is among the main obstacles that reduce translocation success. Scientists should therefore test a variety of translocation methods to reduce dispersal when moving wildlife between sites. The objective of this research was to examine how translocation method (hard- vs. soft-release) and habitat structure (continuous vs. patchy) affect movement of translocated turtles. A hard-release consists of releasing individuals to their new environment without any prior acclimation, whereas a soft-release forces animals to spend time at the release site prior to release. Our results suggest that the most effective translocation technique depends upon habitat structure. A soft-release was effective in minimizing post-release dispersal of translocated turtles in a continuous lotic habitat as there was no difference in the movement of soft-released and resident turtles. However, hard-released turtles undergo extensive movement when translocated to a continuous lotic habitat as hard-released turtles had greater movement than resident turtles. When the release site consists of a patchy wetland complex, a hard-release translocation may be effective as there was no difference in the movement between resident and hard-released turtles. Our study suggests that both the habitat structure of the release site and translocation method play a role in the movement patterns of translocated wildlife. Semi-aquatic turtles or species with poor vagility may make better candidates for hard-release translocations in patchy habitats because these species may be less likely or unable to disperse long distances as result of their behavior, physiology, or the structure of the release site. [ABSTRACT FROM AUTHOR]

The article focuses on the use of ring counts in determining the age of Egyptian tortoises Testudo kleinmanni. The study conducted by the authors was done in Zaranik Protected Area in North Sinai, Egypt, where they photographed wild tortoises between 2006 and 2010 to obtain graphic database. Adobe Photoshop Elements 8.0 was used to view the photographs and the number rings on the shells and found that hatchlings did not have any rings. They conclude that ring count is ideal for determining the age of young Egyptian tortoises, but not for larger, sexually mature ones.