Brief communication: Loss of life due to Hurricane Harvey

An analysis was made of the loss of life caused by Hurricane Harvey. Information was collected for 70 fatalities that occurred due to the event and were recovered within the first 2 weeks after landfall. Most fatalities occurred due to drowning (81 %), particularly in and around vehicles. Males (70 %) and people over 50 years old (56 %) were overrepresented in the dataset. More than half of the fatalities occurred in the greater Houston area (n = 37), where heavy rainfall and dam releases caused unprecedented urban flooding. The majority of fatalities were recovered outside the designated 100- and 500-year flood hazard areas.

The punctuated seaward migration of Pacific lamprey (Entosphenus tridentatus): environmental cues and implications for streamflow management

We investigated emigration timing of juvenile Pacific lamprey (Entosphenus tridentatus) over a 10-year period in the Sacramento River, California, USA. Emigration was punctuated with 90% of macrophthalmia in daily catches of at least 50 individuals. Macrophthalmia were observed primarily between November and May, with among-year variation in median emigration date over four times that of sympatric anadromous salmon. Our best model associating catch and environmental factors included days from rain event, temperature, and streamflow. We found strong evidence for an association of catch with days from rain events, a surrogate for streamflow, with 93% of emigrants caught during an event and the two subsequent days. Emigration was more likely during nighttime during subdaily sampling after accounting for the effects of factors significantly associated with daily catch. These results emphasize the importance of natural variation in streamflow regimes and provide insight for management practices that would benefit emigrating lampreys, such as synchronizing dam releases with winter and spring storms to reduce migration time, timing diversions to avoid entrainment during emigration windows, and ensuring streamflows are sufficient to reach the ocean, thereby avoiding mass stranding events.

Tracking the origin and dispersion of contaminated sediments transported by rivers draining the Fukushima radioactive contaminant plume

This study was conducted in several catchments draining the main Fukushima Dai-ichi Power Plant contaminant plume in Fukushima prefecture, Japan. We collected soils and sediment drape deposits (n = 128) and investigated the variation in 137Cs enrichment during five sampling campaigns, conducted every six months, which typically occurred after intense erosive events such as typhoons and snowmelt. We show that upstream contaminated soils are eroded during summer typhoons (June–October) before being exported during the spring snowmelt (March–April). However, this seasonal cycle of sediment dispersion is further complicated by the occurrence of dam releases that may discharge large amounts of contaminants to the coastal plains during the coming years.