Chemical patterns of colony membership and mother-offspring similarity in Antarctic fur seals are reproducible.

first_imgReplication studies are essential for evaluating the validity of previous research findings. However, it has proven challenging to reproduce the results of ecological and evolutionary studies, partly because of the complexity and lability of many of the phenomena being investigated, but also due to small sample sizes, low statistical power and publication bias. Additionally, replication is often considered too difficult in field settings where many factors are beyond the investigator’s control and where spatial and temporal dependencies may be strong. We investigated the feasibility of reproducing original research findings in the field of chemical ecology by performing an exact replication of a previous study of Antarctic fur seals (Arctocephalus gazella). In the original study, skin swabs from 41 mother-offspring pairs from two adjacent breeding colonies on Bird Island, South Georgia, were analyzed using gas chromatography-mass spectrometry. Seals from the two colonies differed significantly in their chemical fingerprints, suggesting that colony membership may be chemically encoded, and mothers were also chemically similar to their pups, hinting at the possible involvement of phenotype matching in mother-offspring recognition. In the current study, we generated and analyzed chemical data from a non-overlapping sample of 50 mother-offspring pairs from the same two colonies 5 years later. The original results were corroborated in both hypothesis testing and estimation contexts, with p-values remaining highly significant and effect sizes, standardized between studies by bootstrapping the chemical data over individuals, being of comparable magnitude. However, exact replication studies are only capable of showing whether a given effect can be replicated in a specific setting. We therefore investigated whether chemical signatures are colony-specific in general by expanding the geographic coverage of our study to include pups from a total of six colonies around Bird Island. We detected significant chemical differences in all but a handful of pairwise comparisons between colonies. This finding adds weight to our original conclusion that colony membership is chemically encoded, and suggests that chemical patterns of colony membership not only persist over time but can also be generalized over space. Our study systematically confirms and extends our previous findings, while also implying more broadly that spatial and temporal heterogeneity need not necessarily negate the reproduction and generalization of ecological research findings. © 2020 Tebbe et al.last_img read more

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OSV crew detained in Angola for months under ‘false charges’

first_imgTwo Croatian offshore workers have reportedly been held captive by the Angolan authorities, under what they claim to be false charges for  ship fuel theft.According to Croatian media, the two seafarers Vanja Maričić i Duško Jelača, have been unable to leave Angola for almost three months.The pair sailed on the Sutton Tide platform supply vessel owned by Sonatide, a joint venture between Tidewater and Sonangol, when they were arrested in late March 2017.Novi List has written that the shipowner reported the crew, including the two men, of stealing fuel from the vessel, leading to their arrest in the Soyo port of Angola on March 24.Describing the arrest, one of the people in question told to Novi List: “More than forty policemen were waiting for us at the dock, together with the company representatives. They then started searching the command bridge, they dismantled and turned everything upside down.“The seafarer said that after an hour of search the company representative asked him what was going on.“I replied that I did not know and that I assumed that it was a police exercise because at that point I couldn’t have imagined that something like this could happen.“He said that while the raid found no irregularities, the police seized the seafarer’s passports, and took the crew to a local police station for interrogation.It was only then that the crew found out what the charges were – a theft of 104 cubic meters of ship fuel.“One of the crew members had reported to the company that on March 1, between 3 and 6 am in the territorial waters of the Congo, we unloaded the fuel from the ship to another vessel,“ the captain of the ship.The company then, based on that report, informed the police, leading to the detainment of the crew, which has denied the fuel theft allegations.The captain further said that all the information on the charges were given in an unofficial manner „because they did not give us any official documents, even though they took our passports and put us to a hotel.“He also said that a police inspector then came to the hotel, asking from the crew to sign some documents in Portuguese – which they do not speak. The crew, also including two Ukrainians and one Russian, refused and, according to the captain, it would later turn out the documents were an admission of guilt for all the criminal offenses they had been charged with.The Croatian Sailors UnionIn a statement on Tuesday, the Croatian Sailors’ Union said it was doing everything in its power to make life easier for the two sailors in custody. The union has also reached out to the ITF seeking support.“It is an accusation without arguments. This is a strange story started by the company (shipowner) to prevent or deter, workers from doing similar acts. We believe they chose Angola as a place known for corruption to be able to perform the move, but they chose the wrong crew.”The union further said, “the evidence clearly shows that there was no shortage of fuel on the ship, nor that there was a surplus of 104 cubic meters which could have been sold.”The two Croatian sailors along with other crew members, reportedly from the Philippines, Ukraine, and Russia, are not allowed to leave the country for the duration of the investigation. Angolan crew members have been released.Sonatide did not respond to Offshore Energy Today’s request for comment on the case.As for the vessel itself, the Sutton Tide’s latest AIS data show it is an operation, having recently left Total’s Pazflor field, offshore Angola.Offshore Energy Today Stafflast_img read more

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Neptune Energy Wraps Up Integration with Former VNG Norge

first_imgNeptune Energy has completed the integration with the former VNG Norge business. The integrated business, ‘Neptune Energy Norge’, will become the operator of the Fenja field development project in the Norwegian Sea, the company informed.As of December 04, 2018 the merger between Neptune Energy Norge and VNG Norge was completed.The entire business of former VNG Norge, including participating interests in production licenses, operatorships and employees, have now been merged into Neptune Energy Norge.Fenja (PL 586), an oil and gas field under development in the Norwegian Sea, is Neptune’s first operated development project in Norway. It lies 120 km north of Kristiansund, with estimated recoverable resources in excess of 100 million barrels oil equivalent (Pil reservoir).The field is a subsea development with tie-back to Njord A and the first oil is targeted for 2021.Anne Botne, country director for Neptune Energy, said: “The transaction and integration of former VNG Norge adds a strong team as well as competitive growth assets to our portfolio on the Norwegian continental shelf. Fenja is our first development project in Norway. It will feature innovative solutions enabling production through long distance tiebacks to existing infrastructure, thus capturing value and reducing emissions in line with our strategy. By leveraging Neptune Energy’s operational experience and existing contracts, we aim to realize additional opportunities and synergies from Fenja to our two other operated development projects in Norway, Cara and P1 in the North Sea.”The organisation will be led by managing director Odin Estensen as of January 02, 2019.last_img read more

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