Many folks familiar with my volunteer work as a Cook Inlet
beluga whale volunteer monitor usually ask me two questions: “How many beluga
whales do you see?” and “How many beluga whales are there?”
In this blog entry, I address the first question.
In my recent sessions at Ship Creek, my typical response to
“how many did you see” response is “none-zero-nada.” I encountered beluga whales in only one of my
seven sessions at Ship Creek in September. In the one session, my team counted
three beluga whales--an adult, a juvenile, and a calf. In the other six sessions, I saw none—a
“batting average” of .142. Not bad
considering the Ship Creek is the station with the least number of sessions
where beluga were sighted as a percentage of total observation sessions for the
month of September.
Monitoring Station Data for Beluga Whales, September 1 to 30, 2019
|
|||
Station/Location
|
Number of Sessions
|
Number Session Where Beluga Were Seen
|
Total Number of Beluga Whale Reported
|
Ship Creek—Knik Arm
|
32
|
12 (37.5%)
|
50
|
Bird Point/MM 95.2 Pullout—Turnagain Arm
|
26
|
24 (92.)%)
|
392
|
Twenty Mile River Turnagain Arm
|
11
|
7 (63.7%)
|
76
|
Data from Alaska Beluga Monitoring Partnership Siting Log
Webpage (accessed on October 12, 2019, https://akbmp.org/beluga-observation-log/)
Two necessary conditions determine whether we observe beluga
whales during a session. The first
factor—presence of beluga whale--seems obvious.
If the whales don’t show up, they can’t be counted. The second factor—did the observers see the
whales--seems equally as obvious. You can’t count what you can’t see. Of course, you have to know what to look. Our training and experience help with that aspect.
To address the first condition, the research protocol
locates observation stations near anadromous streams where the beluga’s prey
species, salmon, are likely to be present.
The protocol sets the timing of the sessions around the time of high
tide when beluga may safely navigate the shoals and flats of Knik and Turnagain
Arms in order to feed on their prey. Biology
and oceanography largely satisfy this condition.
The second condition is more variable. A number of factors influence whether the volunteers
observe and record the beluga whales.
The physical environment--glare, sea state, weather conditions--all could
affect the ability of an observer to see the beluga whales.
Rain and reduced visibility are environmental factors. We note the conditions for each session and if they change during the session. |
Other factors are related to the individual
observer and include scanning technique; the expanse of the area scanned;
visual acuity; attentiveness, and so on.
The number of observers has an effect—the more eyes looking for
something the more likely it is seen. A
final factor might be the frequency of observers during a session and the
number of beluga whales in each encounter.
That is, the number of pods passing by the observation point and the
number of beluga in each pod increase the likelihood they will be seen. The protocol can control some of potential
observation errors to some degree.
October is pretty much shaping up to be a repeat of
September for me. I am comforted by the
knowledge that negative observations (no beluga seen) provide important
data. I describe beluga whale counting
as “hours of scanning, punctuated by minutes of intense observation and data recording.” I will keep on going to Ship Creek. You can’t see them if you are not there to
see them.
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