Mannus Creek is one of many waterways in Australia that have been inundated with ash and debris following the devastating bush fires this spring and summer, killing fish and other aquatic life and fouling drinking water supplies.
Eel larvae face a long journey from their spawning grounds in unknown parts of the Western Pacific Ocean to the freshwater rivers and streams of New Zealand where they spend most of their lives.
A historic slow-moving flood of polluted Mississippi River water loaded with chemicals, pesticides, and human waste from 31 states and two Canadian provinces is draining straight into the marshes and bayous of the Gulf of Mexico —the nurseries of Arnesen’s fishing grounds—upsetting the delicate balance of salinity and destroying the fragile ecosystem in the process.
LakeSPI surveys have been carried out on 12 Rotorua Te Arawa lakes (Ōkāreka, Ōkaro, Ōkataina, Rerewhakaaitu, Rotoehu, Rotokākahi, Rotomā, Rotomāhana, Rotoiti, Rotorua, Tarawera, and Tikitapu) since 2005 and NIWA freshwater ecologist Tracey Burton says she has seen positive and negative changes.
NIWA freshwater fish scientists are trying to understand how long they can swim at given speeds – between rests - and how much variation there is between fish of the same species.