April 2023

We first collared P36 on the 3rd March, 2022 – a young male mountain lion captured in Taylor Mountain Regional Park with the support of Sonoma Regional Parks. We believe he is the offspring of female P12 and part of a massive litter of 5 cubs who all survived to dispersal age. A couple of days after collaring him with a GPS radio tracking device, we observed him leaving the area heading in a North-Easterly direction. It appeared he had his eye on Mount St. Helena, the highest point nearby with an elevation of 4,312’, bordering Lake, Napa and Sonoma Counties. He skirted the mountain heading north, but soon thereafter returned from Lake County to spend a few months in the Healdsburg area (Fig 1).

Fig 1. Male mountain lion P36 GPS data from first collaring at Taylor Mountain, showing the first few months dispersal wandering long distances but more recently staying in one area

In November we saw P36 move south, safely crossed HWY101 north of Healdsburg, before crossing the Russian River where he headed south towards Bodega. Here a GPS location we received showed him reaching the Pacific coastline at a waterfront parking area in Bodega - "So this is the Pacific", he must have said!(Fig. 2). Since then, he headed further south, visiting hundreds of private ranches, Point Reyes National Seashore, Muir Woods National Monument, Indian Tree Open Space Preserve and more, even going right up to the Golden Gate Bridge (see: https://www.truewild.org/true-wild-blog/march-2023 ) (Fig. 3).

Fig 2. Young male mountain lion, P36 reached the Pacific Coast for the first time at Bodega on the 26th November 2022.

Fig 3. P36 dispersal en-route to the Golden Gate Bridge.

Mountain lions are solitary cats. For the most part, the only time you see mountain lions together is when a mom has her offspring with her (when older, they can be as big or bigger than her), or when a male and female are mating for a couple of days. Young mountain lions, particularly males, are forced to leave their natal range somewhere between 12 and 18 months old. These dispersal individuals will then move around for some time trying to avoid conflict with older, territorial adult lions until they are old and strong enough to challenge for a territory of their own. During this time they may use sub-optimal habitat to avoid bumping into adult established lions. Males usually disperse further than females. In 2011 a male lion was hit and killed by a car in Connecticut after travelling over 1,700 miles from the Black Hills in South Dakota!

One interesting aspect of the movement of dispersal animals is understanding the cues that lead them to choose a particular route or direction when dispersing. P36 has provided us with some interesting data to analyze, where his routes often seem connected to elevated places in the landscape. It appears he selects what looks like a suitable area from some way off, then heads in that general direction. Mountain lions select for areas with cover and often use creeks or drainages to move in. These riverine areas are sometimes key corridors for the younger lions to move through urban or densely human populated areas. Mountain lions are excellent indicators of whether there is sufficient natural connectivity for wildlife in an area. The North Bay of California is a particularly interesting area to study mountain lions as it is effectively the “end of the road” for any dispersal cats moving down from their northern source populations. Mountain lions are unlikely to cross into the South Bay from Marin, Sonoma and most of Napa.  A recent foray took P36 east over the 101 into Tiburon and then back north again - crossing the 101 twice (Fig. 4). Considering a male mountain lion would preferably have a home range of well over 100 sq.miles, Tiburon would not be a good area to settle in.

Fig 4. P36 dispersal en-route to Tiburon.