by Emma Hurley, Scientific Technician …
HOBOS, no, not homeless humans, but temperature gages. As part of our monitoring work, we place water and air gages into the river. We place them all over the watershed, in mains stems and in multiple tributaries. Water temperature is one of the most important factors in the health of stream ecosystems and the fish they support.
Temperature affects salmonid egg and fry incubation, fish metabolism, resistance to disease, and availability of oxygen and nutrients. Our main goal with the HOBOs is to collect the maximum temperature of each location, so we put them into the stream in spring and they through the summer season
(usually the peak temp is around late June/July when our summer is hot and days are at their longest. We just collected the last of the HOBOs out of the river, we will be downloading the data, cleaning them up and getting them ready for next season. We place the water devises in areas with good flow, out of sun and with enough water that they will not dry up. We place a corresponding air gage nearby in an area that will not be hit by sunlight.