More aggressive sea turtles win fights over foraging resources independent of body size and years of presence

Underreported in-water behaviours of the loggerhead sea turtle:Foraging on sea cucumbers

“…All four observations took place in Agios Sostis area, around Agios Sostis Islet at the northwest part of Laganas Bay, Zakynthos, see Figure 1 for the approximate locations. The reef around Agios Sostis Islet is a well-known foraging ground in which resident male and juvenile turtles of Zakynthos prey on the sponge Chondrilla nucula which is abundant on this reef, (Papafitsoros and Schofield, 2016;Schofield et al, 2022). All the three turtles in the observations below have been such long-term residents and they have been logged in a existing photo-identification database consisting of more than 1500 individuals from this site, (Schofield et al, 2020;Papafitsoros et al, 2021).…”

“…In-water observations, citizen science and photo-identification have also revealed the existence of a small year-round resident population (approximately 40 individuals) consisting mainly by adult males and juveniles (Papafitsoros et al, 2021;Papafitsoros et al, 2023). These individuals can be regularly seen foraging on sponges (Chondrilla nucula), molluscs (Papafitsoros and Schofield, 2016;Schofield et al, 2022), as well as discarded fishermen bycatch at a small port in Laganas Bay, (Agios Sostis port; author's personal observations).…”

Underreported in-water behaviours of the loggerhead sea turtle:Getting buried in the sand

“…The turtle was intermittently foraging for sponges until 16:56 where the first part of the observation ended. During that period, it also attacked another foraging male in the area, see Schofield et al, 2022 for the nature of these aggressive interactions. The observation resumed at 17:19 and the turtle was swimming around the area until 17:24.…”

“…foraging and interacting with other turtles, during the summer periods (author’s personal observations), and also immediately before exhibiting this behaviour. We speculate that self-burying might be a camouflaging behaviour that leads to a decreased chance of getting spotted by other turtles and thus being attacked by them as it is typically done in that site (Papafitsoros and Schofield, 2016; Schofield et al ., 2022) and/or prevent them from being spotted by predators as well. Uninterrupted resting behaviour can provide an opportunity to conserve energy between foraging events and this self-burying behaviour might just facilitate this.…”

“…In-water behaviours of sea turtles have been well described in the literature, using a variety of means like direct observations (Booth and Peters, 1972; Schofield et al ., 2006; Bennett and Keuper-Bennett, 2008), animal-borne cameras (Seminoff et al ., 2006; Thomson et al ., 2015), remotely operated vehicles (Smolowitz et al ., 2015; Dodge et al ., 2018), static sea floor cameras (Zamzow, 1998) and drones (Schofield et al ., 2017b). The majority of the studies typically examine standard in-water behaviours like mating (Booth and Peters, 1972; Schofield et al ., 2006; Schofield et al ., 2017a), foraging (Smolowitz et al ., 2015; Wallace et al ., 2015; Papafitsoros and Schofield, 2016; Schofield et al ., 2022), avoiding predators (Hounslow et al ., 2021), cleaning (Zamzow, 1998; Sazima et al ., 2004; Schofield et al ., 2017b), and intraspecific interactions (Thomson et al ., 2015; Gaos et al ., 2021; Schofield et al ., 2022). However, since most animals are observed in small time scales, e.g.…”