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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 six most important threats for petrels and shearwaters

The six most important threats for petrels and shearwaters

Shearwaters and petrels (hereafter petrels) are highly adapted seabirds that occur across all the world's oceans. Petrels are a threatened seabird group comprising 120 species. They have bet-hedging life histories typified by extended chick rearing periods, low fecundity, high adult survival, strong philopatry, monogamy and long-term mate fidelity and are thus vulnerable to change. Anthropogenic alterations on land and at sea have led to a poor conservation status of many petrels with 49 (41%) threatened species based on IUCN criteria and 61 (51%) suffering population declines. Some species are well-studied, even being used as bioindicators of ocean health, yet for others there are major knowledge gaps regarding their breeding grounds, migratory areas or other key aspects of their biology and ecology. Here, 38 petrel conservation researchers summarize information regarding the most important threats according to the IUCN Red List of threatened species to identify knowledge gaps that must be filled to improve conservation and management of petrels. Research advances on the main threats for petrels are highlighted: invasive species at breeding grounds, bycatch, overfishing, light pollution, climate change, and pollution. An ambitious goal is proposed to reverse at least some of these six main threats, through active efforts such as restoring island habitats (e.g. invasive species removal, control and prevention), improving policies and regulations at global and regional levels, and engaging local communities in conservation efforts. The clear message that emerges from this review is the continued need for research and monitoring to inform and motivate effective conservation at the global level. informacion[at]ebd.csic.es: Rodríguez et al (2019) Future directions in conservation research on petrels and shearwaters. Front Mar Sci DOI: 10.3389/fmars.2019.00094


https://www.frontiersin.org/articles/10.3389/fmars.2019.00094/abstract