River Otter Demography Data

Welcome citizen scientists to the river otter demography project results page! Thanks to over 20 years worth of data collection by all you kayakers, white water rafters, surfers, fishermen, bird watchers, students, and amateur naturalists, we understand much more about the local river otter populations of Humboldt and Del Norte county than ever before. Using spatial and statistically analysis tools, we have started to address some of the project's original research goals including questions on spatial and temporal variation in otter distribution and behavior. We also investigated a few questions of our own related to citizen science effort over time and where suitable habitat for otter occurs in Humboldt and Del Norte county. Thanks to all your efforts over the years, we are happy to present some of our preliminary research findings below!




Figure 1. Map showing River Otter sightings submitted by citizen scientists from 2001 – 2014 in Humboldt and Del Norte Counties. World Geodetic System 1984, Universal Transverse Mercator Zone 10 North.




Figure 1a. Map showing River Otter sightings as they change over time in Humboldt and Del Norte Counties. World Geodetic System 1984, Universal Transverse Mercator Zone 10 North.


Otter Data Summaries


Logo 1. Otter locations were spatially clustered around popular public lands (with high levels of human traffic) -The four main clusters were located in Redwood National Park, Humboldt Redwoods State Park, North and South Humboldt Bay, and Del Norte waterways

2. The greatest number of citizen science otter sightings were submitted in 2009 while the lowest number of sightings were submitted in 1999

3. Otters were most frequently reported while swimming and diving and infrequently reported while foraging

4. Otters were primary observed between the hours of 0900 and 1800

5. Suitable otter habitat in Humboldt and Del Norte county is influenced by biotic and abiotic variables such as elevation, distance to river, and land cover type

 




















Figure 1a. Map showing spatial clustering of River Otter sighting in Humboldt and Del Norte Counties. World Geodetic System 1984, Universal Transverse Mercator Zone 10 North.


 



All otter photographs by Talia Rose