Gabriel Chiriac has been involved with the sampling of sediment from the river's bottom using the new "air-lift" sampler. "It's my first experience with air-lift sampling," says Chiriac. "We have taken samples from depths up to 11 meters." Before the JDS2, Chiriac used the older, traditional methods of "kick-and-sweep" and dredging. "But we couldn't get to such big depths before," he adds. "It's possible that Romania will get its own sampler in the future."
The samples taken provide useful and interesting information about the Danube's deep invertebrates communities, which had not yet been studied in any great detail. "Since the JDS2 started, together with my team colleagues Patrick Leitner and Wolfram Graf, we noticed nearly 110 taxa of invertebrates along the 2,000 km that we passed," he says. More detailed future investigations of the sediment and species sampled could result in more, including the identification of a shrimp species found earlier that still remains unidentified.
Carmen Hamchevici and Mary Craciun have been involved in numerous tasks such as sampling, processing, on-board analyses, bottle preparation, labeling and the delivery of samples to designated laboratories. "The JDS2 is the most difficult survey on the Danube River that I was involved in so far," says Hamchevici, who participated in three earlier surveys including the JDS1. "There have been so many different types of samples and analyses required, and sample delivery has also been quite complex. But the invisible bond among the core team members makes all the difficulties become the nicest memories."
Romanian fish expert Grigore Davideanu joined the JDS2 Fish Team in Baja, Hungary. "We need to use our technical skills such as boat driving and improvise solutions almost every day," he says. "It was very exciting to find new fish species that we never encountered in our previous experiences. For example, I never found a Pelecus cultratus, a carp species." Davideanu also found night fishing particularly interesting "as we can find species that usually do not show up during day fishing. During the night, we also can capture bigger individuals from predatory species that come into shallow waters to feed."
Beyond the JDS2 Core Team members, there were also more than 20 Romanian biologists, chemists, engineers and fish specialists from the National Romanian Team who participated. Members took samples from the Danube and its tributaries according to a preset programme, and helped out with the processing of samples.
Finally, Romanian chemist Nicoleta Neacsu joined the team in Moldova Veche, Romania, to support Hana Hudcova with sieving the sediment samples, until the survey's end in Tulcea.
