An analysis of crowd-sourced mountain lion sightings in California. Aggregation of these admittedly imperfect data points may be useful in identifying where the probability of human-puma interaction is increasing, to then determine appropriate action plans to reduce risk to humans and wildlife.

1. Puma Sightings
Can they contribute to science?

2. Some Puma concolor facts for
California
 Apex predator
 California population estimated at 4,000-6,000
 Extensive habitat across the state
 Coincides with deer habitat
 Possibly 30-40 Puma in Santa Cruz Mountains
 Territories and populations socially regulated
 An individual’s range can be as large as 100
square miles
 Major threats:
 Habitat fragmentation & genetic isolation
 Vehicles, disease, shooting, wildfires

3. Methodology
 Publicly reported puma sightings recorded from multiple sources &
mapped
 San Mateo County police reports
 News articles
 Blogs & forums
 iNaturalist
 YouTube
 JRBP camera traps
 >330 reports during an 8-year period, >50 cities and towns
 Sightings rated by degree of confirmation: Confirmed, Probable, Kill
(carcass from likely kill by Puma), Unconfirmed
 Data narrowed to sightings occurring within a Greater Bay Area
quadrangle, Sept. 2009-May 2011 (150 reports)
 JRBP photos used as control

4. Data Challenges & Limitations
 Inconsistent observation and reporting
 False positives
 Under reporting in areas where Puma more common
 Based on chance
 Newsworthiness varies
 News archiving: older data less available
 Small numbers at municipality level
 Many underlying variables – data inherently
“messy”

5. Not a mountain lion…

6. So why bother?
 Numbers are significant in aggregate
 Qualified sightings can provide additional puma
movement data beyond camera trap locations &
radio-collared cats
 Limitations exist on both of these methods
 High number of sightings and/or high-profile events
can pinpoint localities where public education and
responder protocols are needed

7. Initial results
 Quadrangle
covers area
within San
Rafael-
Martinez-
Gilroy-Santa
Cruz
boundaries
 277 sightings
within quad
 8 year time
period

8. Narrowed to likely sightings
 Confirmed, probable
and kills only
 8-year period (2004-
2011)
 175 data points
within quad

9. Likely sightings, 2009-2011
 Confirmed, probable &
kills only
 Sept. 2009 – May 2011
(corresponds to JRBP
camera trap Puma
sightings)
 119 data points within
quad; 76 excluding
JRBP camera traps

10. Sightings show surprising
degree of confirmation
32%
16%
9%
43%
Puma Sightings 2004-2011
excluding JRBP cameras
Confirmed
Probable
Kill
Unconfirmed
57%
Likely
 233 sightings
 Confirmed: Photo/
video, wildlife officer
corroboration, or
multiple witnesses
 Probable: Credible
description (“long tail”
important)
 Kill: Deer or livestock
carcass, ideally with
wounds identified as
likely Puma-inflicted

11. Dangerous Puma encounters
are down…
Source: San Jose Mercury News April 4, 2011

12. …but reported sightings
appear to be increasing
 2011 data
extrapolated to
full year (50
actual sightings
so far, Jan-
May)
 Excludes JRBP
cameras
 Caveat: under-
recording of
older years
0
20
40
60
80
100
120
140
2004 2005 2006 2007 2008 2009 2010 2011
Greater reporting possibly a
result of greater awareness?
Numberofreportedsightings

13. Seasonality of sightings is
indeterminate
 Possible
pattern in
data; not clear
 Possible
correlation
with deer
movement
patterns?
 JRBP
differences
could be due
to sample size
 More research
needed
0
10
20
30
40
50
60
70
80
2004-2011
2009-2011
JRBP Camera
Traps

14. Time of day: Morning &
evening sightings most likely
 Time
segments:
 Early a.m.
(EAM):
00:00-5:59
a.m.
 A.M. (AM):
6:00-11:59
a.m.
 Afternoon
(AFT):
12:00-5:59
p.m.
 Evening
(EVE): 6:00-
11:59 p.m.
 198 sightings;
excludes kills
0 10 20 30 40 50 60 70 80
EAM
AM
AFT
EVE
20
72
37
69
7
27
6
28
4
7
5
13
8
24
21
24
Unconfirmed Sightings
Probable Sightings
Confirmed Sightings
All Sightings
Evening Confirmed +
Probable reports =
42% of Total
Afternoon Confirmed +
Probable = 11%
Morning Confirmed +
Probable = 35%
Early Morning
Confirmed+
Probable = 11%

15. Daytime sightings not bizarre
 Daytime = 8:00 a.m. – 5:00 p.m.
 24 % of total confirmed sightings
This is consistent with other Puma activity studies1
8:15 8:45 9:00 9:55 10:00 11:00 12:00 13:00 15:30 16:16 17:3516:30
• 9/23/10
Pescadero: Puma
behind school
• 3/29/11 Redwood
City : Puma shot in
neighborhood
• 10/14/10 Pescadero: Puma
behind school
• 10/21/07 Gilroy: Cub found
eating dog food
• 6/13/06 Pleasanton: 50-60 lb.
Puma shot near condo
• 9:00, 9/13/10
Morgan Hill: Puma
spotted, escapes
• 9:55, 1/13/05
Palo Alto: 50-lb.
male Puma
spotted, escapes
• 1/12/10 Los
Gatos Older
male struck,
killed by car
• 4/29/05 San
Jose Photo taken
of 80-lb puma in
yard
• 8/31/08 Portola
Valley Credible
sighting near
yard
• 6/29/08
“daytime”
Morgan Hill
YouTube
video
• 5/17/04
Palo Alto
Puma shot
by police
• 11/1/08
Saratoga
Riders see
Puma in
open space
• 1/31/10 “late
after-noon” La
Honda Hikers
approached by
2 Puma
• 1/1/07 Portola
Valley Puma seen
by 3 people
• 3/12/11
Los Altos
Puma on
security cam
1 Hansen, 1992

16. Sightings by locality probably
do not reflect amount of actual
Puma movement
0
5
10
15
20
25
30
35
40
45
50
aptos
atherton
belmont
benlomond
berkeley
BigBasin
bouldercreek
brisbane
burlingame
capitola
Clayton
dalycity
danville
emeraldhills
felton
fremont
gilroy
halfmoonbay
Hayward
hillsborough
lahonda
livermore
losaltos
losgatos
MillValley
millbrae
montara
Moraga
morganhill
mossbeach
novato
oakland
pacifica
paloalto
pescadero
pleasanthill
pleasanton
portolavly
redwoodcity
sananselmo
sancarlos
sanjose
SanLeandro
SanLorenzoValley
sanmateo
SanRamon
santacruz
saratoga
ScottsValley
soquel
stanford
Swanton
WalnutCreek
woodside
Confirmed Probable Kill Unconfirmed
JR Camera
traps
High variability in number, confirmation level of sightings across communities

17. Expected & actual impact of
human population density on
sightings
 We might expect to see a relationship
between human population density, actual
Puma movement, and propensity to report
sightings…
#ReportedSightings
Population density
More rural = Puma
considered more
commonplace;
observers less likely
to report sightings
More urban =
Puma activity
is unusual but
there is a
much higher
propensity to
report it
A hypothetical “sweet spot” may
exist in semi-rural areas where
Puma activity is not unusual but
people consider sightings
noteworthy

18. …Data say “sort of”
 JR camera traps
excluded (not a
function of
human
observation)
 Some outliers
can be
explained, but
not all
 Relationship
looks better on
log scale; don’t
know why!0
5
10
15
20
25
30
1 10 100 1000 10000 100000
Population density per locality
#ofreportedPumasightings
Pescadero
schoolyard
sightings
Portola Valley,
Woodside
• Outliers include
Gilroy, Morgan
Hill with a high #
of livestock kills.
• Other outliers
have mixed
densities (Palo
Alto, Redwood
City)

19. Education can be prioritized by
community
 Relatively dense
communities with
high %s of likely
sightings should
be prioritized for
education
outreach &
responder
training (Shaded
area)
 Cities in bold
have already had
incident needing
responder
training
Likely
Sightings
as % of
Total
Sightings
per
Locality
Population Density (person/mi.2)
-10%
10%
30%
50%
70%
90%
110%
-4000 -2000 0 2000 4000 6000 8000 10000 12000 14000 16000
= Total # of
Sightings
San Mateo
Berkeley
San Jose
Gilroy
Morgan Hill
Palo Alto
Redwood City
Los Altos
Daly City
Portola Valley
Woodside
Pescadero
Note: JR data omitted

20. Terrain characteristics of
sightings are consistent
 Consistent nearby land features: Always 1 or more
within < 3 miles
 Streambeds
 Open space/parks
 Hilly terrain, often wooded
 These are typical Puma habitat features
 Even “urban” sightings are within 2-3 miles of 1 or
more features
 Berkeley “Gourmet Ghetto” lion, August 2009
 Redwood City Sequoia Hospital puma, March 2011
 Pumas typically travel 0.5 miles/hour;1 thus can travel
2-3 miles in a few hours from a habitat area into
human habitation
1Kevin Hansen, citing Paul Beier, 1992
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
84%
34%
51%
Chart notes:
• Percents sum to >100%
• Terrain rating estimated

21. “Urban” sightings not far from
Puma habitat areas
San
Francisquito
Creek
Berkeley
Redwood City
Palo Alto
Streambeds
Gilroy
1 Mile

22. Conclusions
 Social and news media can be a useful ecology tool
 Citizen science puma tracking
 Even this “messy” data yields some useful information
 Corroborates behavior studies
 Has potential predictive value
 Reported Puma sightings in the greater Bay Area appear to be increasing
 Sightings peak during morning and evening as expected but almost 25% occur
during daytime
 Sightings vary greatly among communities
 Communities can be prioritized for education & training outreach
 There are common terrain features near sightings, even urban ones, that can
possibly be used to anticipate future Puma activity
 Human demographics and Puma behavior data can potentially be combined to
predict human-Puma interaction at a high level

23. Next Steps
 Share results with Felidae Conservation Fund, other researchers
 Tie results in with puma radio movement data – possibly identify
individuals
 Do additional research to add to/scrub data:
 Police reports
 Animal Control
 Conduct more in-depth terrain & seasonality analysis
 Use results to identify areas to find pumas to collar
 Use results to place cameras at likely corridor points
 Develop “citizen science” puma app to capture better data when new
sightings occur
 http://www.surveymonkey.com/s/RR3YTWN

24. Some interesting Puma
sightings
 Video: Los Altos Hills
http://www.youtube.com/watc
h?v=wLXGLgSAZj4
 Video: Morgan Hill
http://www.youtube.com/watc
h?v=Y8DK2RGUXuk
 Video: Ben Lomond (Felidae
Fund)
http://www.youtube.com/watc
h?v=i1axaB_zRn8
 Some photos from JRBP