Data from a long-term culture system for deep-sea mussels Gigantides childressi (from 2014 to 2019)

Data of culturing two batches of G. childressi specimens for altogether 36 and 27 months, respectively. The deep-sea mussels of the first batch (208 specimens, "batch 1") were collected by E/V "Nautilus" using the ROV "Hercules" southwest of New Orleans in the Gulf of Mexico at station GC233 ("Brine Pool NR-1"; 2743.40760N, 9114.77980W) on 13 July 2014 at a depth of 650 m. At this site, cold and high-saline water seeps from the ocean floor and—due to the higher density—fills a "brine pool" which is surrounded by a G. childressi mussel bed (MacDonald et al. 1990). The mussels arrived at GEOMAR (Kiel, Germany) 14 d after being collected. The second batch of G. childressi (35 specimens, "batch 2") was collected by MSV "Ocean Intervention II" using the ROV "Global Explorer" northeast of the first site at station GC249 (27°43.72740N, 90°31.01400W) in 811 m depth on 18 June 2017. The mussels were transported within 4 d by ship and truck to the Fisher deep-sea lab at Pennsylvania State University, State College, PA. Here, the experimental animals were cultured in a recirculating seawater aquarium system (T = 8 °C, S = 34) that continuously received methane-saturated seawater. Seawater methane concentrations were not quantified during this time period. Subsequently, after 2 months, animals were shipped by plane in cooled jars (T = 5–8°C, S = 34) to GEOMAR (travel time < 24 h). There was no mortality during the transport of both batches.