The Maine Stream Temperature Monitoring and Modelling Network

ArrayJuly 3, 2019 at 1:40 pm

Stream temperature is a primary control on the distribution and abundance of fishes and other aquatic organisms.  After all, most are aware that Maine’s iconic salmonid fishes, such as wild Brook Trout, have a close affinity with waters that stay cool year-round.  Hence, having a good understanding of where coldwater resources are and how these patterns may change in the future is something rather important for maintaining habitat for our native fishes, wildlife and their habitats. Since 2014, MDIFW has been working with partners to expand the Maine Stream Temperature Monitoring Network to provide accurate stream temperature information for a wide variety of users and decisions.  The Network’s specific goals include: 1) increase the statewide sensor network and make these data more publicly accessible; 2) contribute Maine data to an evolving regional stream temperature modelling effort; 3) use the model output to predict patterns in temperature for Maine streams; 4) provide stream temperature in map formats for natural resource conservation and management plans; and, 5) spread the word about the effort and its products to anyone interested with how to participate in the Network.

The Maine Water Temperature Working Group was established to develop a coordinated stream temperature monitoring network that could be integrated with regional and national efforts to help identify streams and watersheds that are more likely to remain cooler in the face of climate change.  The group is composed of multiple state agencies, academics, NGOs, Tribes, federal agencies and public groups.  Members follow standardized monitoring protocols for sensor deployment and data collection so methods used by all members are consistent across the state.  Initially, we conducted a comprehensive inventory of existing data for current and past water temperature monitoring efforts and those historically collected records are available in the web-based data management system, EcoSHEDS (http://db.ecosheds.org/). Through the efforts of the Group’s many partners, we are now conducting year-round stream temperature monitoring in more than 300 active stations statewide (Figure 1).

Figure 1.  Current locations of stream temperature monitoring conducted by the Group

The data collected by this effort are used in regional stream temperature models developed by USGS to predict or classify each watershed’s stream thermal characteristics depending on varying climate change scenarios.  Users can explore the effects of various climate change scenarios on Maine’s streams or varying watershed sizes through the Interactive Catchment Explorer (Figure 2;  http://ice.ecosheds.org/sheds/). 

Figure 2.  Modelled wild Brook Trout occupancy in the Piscataquis River drainage under varying thermal conditions.  Darker colors denote higher occupancy rates.  Current thermal conditions (top) and hypothetical 4ºC increase in average July temperature (bottom).

Models can give us an idea of what to expect as conditions change over time.  However, no model is perfect or can predict the future with 100% accuracy.  They can be improved either through continued data collection over additional years as well as through expanding the network’s sensor coverage.  Hence, we could use your help!  If you happen to find an installed thermal sensor (Figure 3), please leave it alone.  It is doing exactly what it’s supposed to do – recording stream temperature every 30 minutes.  However, if you find one that is out of the water for any reason, please let us know.  We’ll check into the situation and redeploy it if possible. 

Figure 3.  A deployed stream temperature sensor on the downstream side of a rock (within red circle). 

You can also actively help with the network if interested.  There certainly are many areas where we would love to add additional sensors.  If you have an interest in the outdoors, streams, and fishing for Brook Trout, please get in touch with us.  There are a variety of ways where anyone can help with the project, ‘adopt a site’ or assist an existing group in some way. We’d love to hear from you!