Autonomous University of Baja California

Ecological traits of sea turtles are strongly influenced by their environment, making these species highly sensitive to climatic variability, particularly under global oceanic and atmospheric changes. Assessing the relationships between environmental variability and sea turtle phenology is critical for understanding potential population responses under climate change and informing adaptive management at critical habitats. We assessed the nesting phenology of Chelonia mydas across three beaches in the Mexican Atlantic (Isla Aguada, Lechuguillas, and Tamul), representing contrasting oceanographic conditions. We used long-term nesting data (2009–2023), to examine temporal coherence between nesting activity and sea surface temperature (SST) and a spatially accumulated precipitation indicator using cross-spectral analyses. The nesting season began in June (eight-day intervals 23-31) and ended in early October across all sites, and its duration averaged 12 ± 0.8 eight-day intervals. Cross-spectral analyses revealed consistent annual coherence between nesting activity and both environmental variables, with SST signals preceding nesting activity by up to approximately 3.9 weeks and precipitation signals by up to 5.3 weeks. These relationships varied among sites and represent temporal associations rather than evidence of direct causation. Our results highlight the relevance of short-term metoceanic variability to nesting phenology within a broader context of interacting environmental and reproductive processes. Integrating phenological indicators with environmental observations can support climate-informed monitoring, improve operational planning, and inform adaptive conservation strategies under future climate scenarios and support climate-informed monitoring and conservation planning.

The 2015–2016 El Niño was one of the most intense events in the Mexican Tropical Pacific and the Gulf of California, characterized by increased temperatures and shifts in water-mass proportions. To quantify these variations and their impact on carbon biogeochemistry, an Optimum Multiparameter (OMP) analysis was implemented using temperature, salinity, and dissolved oxygen (O2) data from three oceanographic cruises (June 2015, March 2016, and October 2017) and Argo float profiles. Results showed that Tropical Surface Water (TSW) contributed ∼50% or more of the upper ∼50 m in June 2015 and > 50% of the upper ∼100 m in March 2016, deepening both the oxycline and the dissolved inorganic carbon gradient (hereafter, the carboncline, defined as the depth of the maximum DIC vertical gradient). This TSW intrusion reconfigured the vertical structure of the water column, directly affecting the biogeochemistry of O2 and dissolved inorganic carbon (DIC). Estimates of biogeochemical residuals (ΔDIC and ΔO2) revealed distinct processes: in June 2015, residuals in the subsurface layer (70–140 m), where Gulf of California Water (GCW) and Subtropical Subsurface Water (StSsW) mix, were qualitatively consistent with aerobic remineralization, although the ΔDIC–ΔO2 regression was not statistically significant. In contrast, in March 2016, a statistically significant photosynthetic signal (ΔDIC < 0, ΔO2 > 0) was detected in the surface layer (0–50 m), spatially coincident with a cyclonic mesoscale eddy observed during the cruise, which may have locally enhanced nutrient supply to the euphotic zone. Under El Niño-Southern Oscillation (ENSO) neutral conditions in October 2017, no statistically detectable ΔDIC–ΔO2 relationship was found. These findings suggest that biogeochemical residuals can distinguish contrasting biogeochemical conditions, ranging from subsurface residual patterns consistent with remineralization to a surface photosynthetic signal coincident with mesoscale activity, within the oxygen minimum zone (OMZ) of the Mexican Tropical Pacific, even though the two El Niño snapshots examined here did not yield a single, generalizable biogeochemical signature of ENSO forcing.

The rapid pace of human-induced environmental change (HIREC) has led to the emergence of ecological traps—situations in which organisms preferentially select habitats based on misleading environmental cues, despite those habitats reducing their fitness, significantly impacting vulnerable species such as sea turtles. This study reviews the concept of ecological traps through a systematic and expert-guided literature review focused on sea turtle ecology, coastal systems, and social–ecological dynamics. From the review, we found that sea turtles’ vulnerability to ecological traps is associated with strong site fidelity, reliance on environmental cues, and exposure to human-induced changes across coastal and marine habitats. However, most studies focused on nesting and hatching, while potential traps in marine foraging habitats remained less investigated. Only a few studies simultaneously evaluated habitat preference, habitat quality, and fitness consequences, which are necessary to empirically identify ecological traps. Such integrated assessments are particularly relevant for identifying potential ecological traps arising from coastal planning, fisheries management, and habitat restoration interventions. Despite the need for further knowledge, research on this topic remains limited, particularly in low- and middle-income countries where ecological traps have been observed but not systematically analyzed. This review proposes elements to support the integration of ecological trap theory into coastal management and governance strategies for sea turtle conservation under rapid environmental change.

Solar ultraviolet (UV) radiation is the primary etiological factor in the development of several cutaneous malignancies, including carcinomas. In this context, the use of sunscreen formulations usually helps to prevent and reduce UV skin damage. The aim of this work was to explore the impact of the process conditions on some relevant physicochemical properties in sunscreens with a formulation based on quercetin Pickering emulsions stabilized with ZnO particles. Four formulations were prepared by controlling the speed and homogenization time using green coffee oil as the external phase and a mixture of stabilizers, water, and polyethylene glycol as the dissolution media. The stability of the emulsified systems was analyzed in terms of time after 28 days of storage by optical microscopy and digital image analysis to determine the mean particle size. The Turbiscan Stability Index (TSI), Sun Protection Factor (SPF), rheological behavior, and antioxidant activity were also evaluated. The system with the highest physical stability, minimal changes in rheological properties, and superior stability during storage time with respect to breakage phenomena was obtained at 15,000 rpm/2 min, with a SPF of 40 and exhibiting one of the highest antioxidant capacities compared to other treatments. This stability was constant during the evaluation period. With these results we established the optimal conditions for the potential development of sunscreens with desirable attributes to reduce the harmful effects of UV radiation in addition to establishing the encapsulation conditions of bioactive compounds and facilitating its scale-up.