Suzanne Teerlink and Larissa Horstmann

Suzanne Teerlink and Larissa Horstmann-Dehn
School of Fisheries and Ocean Sciences, University of Alaska Fairbanks
Conclusions
Juneau Whale Watching
•  May - September
•  Over 200,000 tourist/year
•  35+ boats (ranging from 6 -150 passenger vessels)
•  ~ $25 million in annual revenue
•  2-30 humpback whales in the area at a time
Issue
Humpback whales near Juneau are subject to high
numbers of whale-watching vessels, though, we
lack formal monitoring of whales in this area.
Goal
To evaluate citizen science as a tool in monitoring
humpback whales near Juneau.
Methods
September, 2006
August, 2013
Parameters
Compared
Fig. 1: Example of a re-sighted individual, fluke
matches from separate days allow us to construct
sighting histories for individuals.
- Mark-recapture abundance estimates
using a Huggins closed-capture model
- Site fidelity (cumulative proportion of
re-sights to total sightings)
- Transience (proportion of whales with
single sightings to multiple sightings)
This comparison was intended to objectively
assess biases from whale-watch platforms
(CS) compared to dedicated surveys.
Acknowledgements
This project is funded by the NSF MESAS IGERT and the North
Pacific Research Board. Thank You to Gastineau Guiding Co.
for their extensive participation in this project.
*Photos taken under Scientific Research Permit # 14296
Results
Survey How does CS CS Compare? Site Fidelity 0.56 0.63 Overes,mated Transience 0.55 0.54 Similar Site Fidelity 0.62 0.84 Overes;mated Transience 0.51 0.39 Underes;mated 2013 2014 Fig. 2
Comparison of
mark-recapture
abundance
estimates. Number
below data source
is the total # of
sightings that went
into the analysis.
Error bars 95% CI.
100
Table 1:
Comparison of
data from
dedicated
surveys to
citizen science
data.
2013
80
2014
Drawbacks of Citizen Science
•  Inflated occurrences of re-sightings biases
estimates of sight fidelity and transience.
•  These biases are likely due to the tendency
of whale watching captains to return to areas
where they previously found whales.
Advantages of Citizen Science
•  Utilizes existing platforms (thus decreasing project
overhead and additional vessel traffic).
•  Increases stakeholder participation & education.
•  Especially useful for documentation of whales with high
site fidelity and has potential to be useful in monitoring.
Recommendations
•  Reliable abundance estimates may be possible from
citizen science data if the effort is high enough to
outweigh re-sighting bias.
•  Citizen science data is best used as a compliment to
dedicated surveys- the best abundance estimates
came from combined CS and dedicated survey data.
60
# Whales
We compared sighting history data (Fig. 1)
from 2013-14 contributed photos from
Gastineau Guiding Co. and other sources referred to here as Citizen Science (CS) data to data collected simultaneously from our own
traditional weekly dedicated surveys (Survey).
In 2014, abundance estimates from both Survey and
CS are lower than the known minimum (Total Unique
IDs), and therefore are both underestimations (Fig. 2).
40
20
0
Survey
(85)
CS
(57)
Total
(142)
# Unique IDs
Survey
(144)
CS
(347)
Total
(491)
Abundance Estimate
•  Citizen science effort was relatively small in 2013 and
much higher in 2014 (Fig. 2 – Number in parentheses).
•  Especially in 2014, Transience was underestimated with
CS data (and site fidelity overestimated. Table 1).
•  CS data significantly underestimated abundance in 2013
when effort was low, but was a good proxy in 2014 when
effort was high (Fig 2).
Where to next?
•  Continue citizen science program 2015.
•  Share results with participants and continue to
foster an open, collaborative relationship
with stakeholders.
•  Use AIS vessel tracking data from whale
watching vessels as a proxy for whale
locations to give us temporal-spatial trends
in habitat use within the Juneau area.