Banca de DEFESA: GABRIEL SOEIRO ALEXANDRINO OLIVEIRA

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
DISCENTE : GABRIEL SOEIRO ALEXANDRINO OLIVEIRA
DATA : 15/01/2020
HORA: 10:00
LOCAL: Instituto de Biologia - Universidade Federal da Bahia
TÍTULO:

Habitat selection based on chemosensory cues in loggerhead turtle hatchlings (Caretta caretta Linnaeus, 1758)

PALAVRAS-CHAVES:

sea turtle, chemoreception, habitat selection, conservation, pollution

PÁGINAS: 62
GRANDE ÁREA: Ciências Biológicas
ÁREA: Ecologia
SUBÁREA: Ecologia Teórica
RESUMO:

After hatching on land, sea turtles need to reach the marine realm. However, how hatchlings orient themselves to find their preferred habitat at sea, which may vary among species from coastal (inshore) to oceanic (offshore), is almost entirely unknown. Given adult turtles may rely on olfaction for guidance at sea, it is possible that hatchlings’ first migration is based on chemoreception (olfaction and gustation). However, chemoreception is often impaired by chemical pollution. In one endangered sea turtles species, Caretta caretta, we determined the role of chemoreception on habitat choice, and test whether coastal chemical pollution interferes with this sensory mechanism. In a Y-tank, we presented concomitant distinct seawater flows (coastal and oceanic) and let hatchling turtles free to swim in any of these flows for a period of 10 min. Hatchlings spent significantly more time in oceanic seawater flow, with nearly 70% of the time. However, before reaching the oceanic realm, hatchlings are required to cross coastal waters, which, as a result of human activities, may be polluted (chemically or biologically), for example as a result of sewage discharge. In the second experiment, when hatchlings had to choose between coastal and polluted water (collected from a beach with runoff), the hatchlings could not distinguish between chemosensory cues, suggesting that pollutants disrupt the recognition of suitable habitats by chemoreception. However, this compromise of olfactory preferences in turtle hatchlings leads to higher mortality, increasing the risk of contamination and predation, leading to direct consequences on sea turtle populations.

MEMBROS DA BANCA:
Presidente - 859.394.105-29 - ANTOINE LEDUC - NENHUMA
Externo à Instituição - MATILDE MARIA MOREIRA SANTOS - UC
Externo à Instituição - CRISTIANO VENICIUS DE MATOS ARAÚJO