Browsing by Author "Silva, E."
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- Effect of body size on the long-term reproductive output of eastern Atlantic loggerhead turtles Caretta carettaPublication . Martins, Samir; Cardona, L.; Abella, E.; Silva, E.; Loureiro, Nuno de Santos; Roast, M.; Marco, A.We assessed the relationship between body size and several important life history parameters to understand the demographic significance of interpopulation variability in the body size of loggerhead turtles Caretta caretta nesting on Boa Vista Island (Cabo Verde). The adult growth rate (0.34 +/- 0.60 cm yr-1), annual mortality rate (0.13, 95% CI: 0.12-0.15) and remigration interval (3.1 +/- 1.2 yr) were independent of curved carapace length (minimum curved carapace length [CCLmin]). Conversely, the body condition index decreased significantly with female CCLmin. The clutch size, mean egg mass, mean hatchling straight carapace length and mean hatchling mass increased significantly with female CCLmin. However, there was no relationship between female size and hatching success. Randomization and bootstrapping were used to incorporate variability when calculating the average individual fecundity over 20 yr, a period that accumulated, on average, 94% of the adult mortality. The overall fecundity during this period increased with carapace length at first maturity (71 cm CCLmin: 815 eggs, 95% CI: 653-863; 80 cm CCLmin: 906 eggs, 95% CI: 822-959; 90 cm CCLmin: 1089 eggs, 95% CI: 926-1415). However, only 8% of the adult females nesting on Boa Vista Island are larger than 90 cm CCLmin, and they produce less than 12% of the total annual egg production. The scarcity of large females might result from a shortage of high-quality foraging grounds where females may reach first sexual maturity at a large carapace length and from the combined effect of a small carapace length at first sexual maturity, low adult somatic growth and high adult mortality.
- TRIDENT – Technology based impact assessment tool foR sustaInable, transparent Deep sEa miNing exploraTion and exploitation: A project overviewPublication . Silva, E.; Viegas, D.; Martins, A.; Almeida, J.; Almeida, C.; Neves, B.; Madureira, P.; Wheeler, A. J.; Salavasidis, G.; Phillips, A.; Schaap, A.; Murton, B.; Berry, A.; Weir, A.; Dooly, G.; Omerdic, E.; Toal, D.; Collins, P. C.; Miranda, M.; Petrioli, C.; Barrera Rodríguez, C.; Demoor, D.; Drouet, C.; Serafy, G. El; Jesus, Sergio; Dañobeitia, J.; Tegas, V.; Cusi, S.; Lopes, L.; Bodo, B.; Beguery, L.; VanDam, S.; Dumortier, J.; Neves, L.; Srivastava, V.; Dahlgren, T. G.; Thomassen Hestetun, J.; Eiras, R.; Caldeira, R.; Rossi, C.; Spearman, J.; Somoza, L.; González, F. J.; Bartolomé, R.; Bahurel, P.By creating a dependable, transparent, and cost-effective system for forecasting and ongoing environmental impact monitoring of exploration and exploitation activities in the deep sea, TRIDENT seeks to contribute to the sustainable exploitation of seabed mineral resources. In order to operate autonomously in remote locations under harsh conditions and send real-time data to authorities in charge of granting licenses and providing oversight, this system will create and integrate new technology and innovative solutions. The efficient monitoring and inspection system that will be created will abide by national and international legal frameworks. At the sea surface, mid-water, and the bottom, TRIDENT will identify all pertinent physical, chemical, geological, and biological characteristics that must be monitored. It will also look for data gaps and suggest procedures for addressing them. These are crucial actions to take in order to produce accurate indicators of excellent environmental status, statistically robust environmental baselines, and thresholds for significant impact, allowing for the standardization of methods and tools. In order to monitor environmental parameters on mining and reference areas at representative spatial and temporal scales, the project consortium will thereafter develop and test an integrated system of stationary and mobile observatory platforms outfitted with the most recent automatic sensors and samplers. The system will incorporate high-capacity data processing pipelines able to gather, transmit, process, and display monitoring data in close to real-time to facilitate prompt actions for preventing major harm to the environment. Last but not least, it will offer systemic and technological solutions for predicting probable impacts of applying the developed monitoring and mitigation techniques.