The impact of nest flooding is highly variable in space and time depending on difficult-to-predict factors such as the start of the rainy season and its intensity ( Eisemberg et al., 2016). unifilis ( Caputo, Canestrelli & Boitani, 2005). sextuberculata ( Vogt & Pezzutti, 1999) and P. lewyana ( Gallego-García & Castaño-Mora, 2008), P. However, elevated nest loss due to extreme and/or unseasonal flooding has been widely documented in Podocnemis erythrocephala ( Batistella & Vogt, 2008), P. Nesting in members of the Podocnemididae is usually synchronized to avoid the seasonal flood pulse in lotic waterways. Whilst some turtles show adaptations to predictable changes in water levels ( Kennett, Christian & Pritchard, 1993), extreme flooding events cause dramatic increases in egg and embryo mortality in South American Podocnemididae ( Eisemberg et al., 2016 Páez et al., 2015). Unpredictable water level rises are known to strongly affect freshwater turtle recruitment along seasonally flooded rivers ( Bodie, 2001 Semlitsch & Bodie, 2003 Steen et al., 2012). Increasingly frequent alterations in the seasonal Amazon flood pulse may seriously impact the region’s flora and fauna ( Barichivich et al., 2018 Marengo & Espinoza, 2016). The conservation and recovery of this and other Amazonian freshwater turtles will therefore depend on effective and active management plans that are likely to be more successful with local community involvement ( Campos-Silva et al., 2018 Harju, Sirén & Salo, 2018 Norris, Michalski & Gibbs, 2018b Norris et al., 2019). Precautionary estimates suggest that populations of the once abundant Yellow-spotted river turtle ( Podocnemis unifilis) may experience severe (≥50%) and rapid (<50 years) future losses across 60% (5.3 M km 2) of the pan-Amazonian range ( Norris et al., 2019). Like many tropical species Amazonian freshwater turtles are threatened by deforestation ( Fagundes et al., 2018), climate change ( Eisemberg et al., 2016), and unsustainable exploitation ( Rachmansah, Norris & Gibbs, 2020 Smith, 1979). Management plans should take the possible survival of submerged eggs into consideration as part of species conservation and recovery actions. These findings suggest that Yellow-spotted river turtle eggs and embryos are resistant to short-term submersion, which could help explain the widespread distribution of this species across highly seasonal Amazonian rivers. Egg survival (61.7% (571/926)) was substantially less than hatchling survival (94.2% (599/636)) but within the expected range of values reported for this species.
We released 599 hatchlings (60.4%) from 991 submerged eggs and hatchlings. Healthy hatchlings were then immediately released around the original nesting areas. Hatchlings were maintained in 250–500 L nursery tanks until yolk sac scars had closed. Hatchlings emerged from eggs that had remained underwater for up to two days. The rescued eggs were transferred to a rearing center and incubated. We recovered 926 eggs and 65 premature hatchlings from 74 submerged nests at 16 flooded nesting areas along 75 km of waterways. Here we show that community-based actions saved Yellow-spotted river turtle ( Podocnemis unifilis) eggs submerged by unseasonal flooding and ensured the release of hatchlings. The conservation and recovery of increasingly threatened tropical freshwater turtle populations depends on effective management plans and actions.