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Army ant invasion of leatherback nests in Gabon

Egg mortality is one of the main factors affecting life history and conservation of oviparous species. A massive and cryptic colonisation of many leatherback turtle (Dermochelys coriacea) eggs is presented in the most important rookery for the species in Gabon. A total of 163 nests were exhumed at Kingere beach, revealing that only 16.7% of eggs produced hatchlings. In the 59% of the nests, more than half of the eggs were dead and attacked by invertebrates and 94% had at least one egg affected by invertebrates. The rate of eggs and SAGs (yolkless eggs) affected by invertebrates within a clutch ranged from 0% to 100%, with an average proportion of 39% and 52%, respectively. The most common invertebrates interacting with the eggs were ghost crabs and insects that affected 51% and 82% of the nests, respectively. Crab and insect co-occurred in 33% of the affected nests. Ants, identified as Dorylus spininodis (Emery 1901) were found in 56% of the excavated nests. However, it was not possible to determine if the ants predated alive eggs or scavenged dead eggs. Very often, hundreds of ants were found drowned within dead eggs. Termites and other invertebrates were associated with the clutch environment and identified as opportunistic feeders, being this is the first record of interaction between termites and sea turtle eggs. An unusual ecological interaction within the leatherback clutches between termites and ants was found in 11% of the nests. The abrupt transition between the soil forest and the beach might be favouring a thriving microbial and invertebrate activity in the sand profile that colonises the nests. informacion[at]ebd.csic.es: Ikaran et al (2020) Cryptic massive nest colonisation by ants and termites in the world's largest leatherback turtle rookery Ethol Ecol Evol 2020. Doi 10.1080/03949370.2020.1715487


https://www.tandfonline.com/doi/abs/10.1080/03949370.2020.1715487
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The functional connectivity network of wintering gulls links seven habitat types, acting ricefields as the central node

The functional connectivity network of wintering gulls links seven habitat types, acting ricefields as the central node

The lesser black-backed gull is now the second most abundant wintering waterbird in Andalusian wetlands. Many birds are fitted with GPS loggers on their breeding grounds in northern Europe, and using 42 tagged individuals we studied the connectivity network between different sites and habitats in Andalusia. Thirty seven principal sites (nodes) from seven different habitats (ricefields, landfills, natural lakes, reservoirs, fish ponds, coastal marshes and ports) were identified. By analysing nearly 6,000 gull flights, it was found that Doñana ricefields are the most important node in the network, but that 90% of flights are made between a wetland and a landfill. The 37 nodes are split into 10 functional units (modules) in which gulls tend to fly daily and up to 60 km between a wetland roost site, and a landfill feeding site. This network allows to predict how gulls contribute to seed dispersal, wetland eutrophication, and the spread of pathogens such as antibiotic resistant bacteria. informacion[at]ebd.csic.es: Martín-Vélez et al (2019) Functional connectivity network between terrestrial and aquatic habitats by a generalist waterbird, and implications for biovectoring. Science Total Environm 107: 135886 DOI 10.1016/j.scitotenv.2019.135886


https://www.sciencedirect.com/science/article/pii/S0048969719358814?via%3Dihub#ab0005