by Emma Hurley, Scientific Technician 


Stadia showing location of water HOBO on the lower North Fork

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.


Water (larger) and air HOBOS

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.


The vegetation is lush in early summer when we put HOBOs in place


Deep and Dark on the Little North Fork


More Little North Fork


Don’t go in too deep! Finding a good placement location