2017-2021 newt patrol survey report
The report includes an introduction about Pacific newts biology, their diet and life cycle, and how to distinguish the two species found on Alma Bridge Rd.
The report includes data analysis for all records collected in the first four years of the newt patrol survey, from the 2017-2018 season to the 2020-2021 seasons. You can find data about the survey itself, such as this table about the number of surveys made by our team, the data we collected, and some conclusions.
3 The total number of dead newts on 2020-2021 is 4,941 newts. See report for details.
In the Past three years, we counted about 5,000 dead newts per year on a 4.2 mile section of Alma Bridge Rd. When broken into months, it is clear that most newts are killed between December-March, and fewer newts migrate during November, April, and May.
Newt migration is directly connected to rainfall. Our data shows that less rain is needed to trigger Pacific newt migration, compared with other salamanders. Interestingly, continuous rainfall is not needed to sustain the migration, as can be seen below. During February 2020, there was no rain, but 904 newts were found dead on the road anyway.
Newt mortality rates were compared with different environmental factors, such as rainfall, temperature, and frost. You'll have to read the report to find out which factors had the most impact on newt movement. To download the full report, click here.