2010
Season Summary
from Observation Post #6
Los Angeles, California, USA
Journey
North thanks Alisa
Schulman-Janiger, Director,
ACS/LA Gray Whale Census and Behavior Project
A Record Low Count
The spring 2010 migration brought a record low count of gray whales reports Alisa Schulman-Janiger. Here are her results:
Number of whales counted:
- Northbound total: 521 (677 last season)
- Northbound
total previous range: 634 – 3,412
- Northbound
calves: 41 (or 7.9% of the northbound
migrants) were seen beginning March
16
to
May
11.
Comparisons to other years:
- Last season we counted 52 northbound cow/calf pairs which was
7.7% of northbound
migrants.
- Spring 1996-1997
brought the record calf count season: 222 calves, or 13.8% of
northbound migrants.
- Previous calf counts have ranged from 11-196 (0.9%-18.5% of northbound migrants)
Some reasons gray whale counts fluctuate each year:
- Variable feeding ground conditions (especially ice coverage)
affect
migratory
timing and corridors;
- Weather conditions (more fog this season affected the
counts);
- Changes in route preferences of whales (at ACS/LA, most southbound gray whales prefer offshore corridors; many northbounders shift
to
nearshore routes);
- Fluctuations in numbers in the wild populations as well as
number of whales that complete the migration.
2010 northward migration peaks and turn-around dates:
- Official turn-around date: February 20
The turn-around date is the first day when the number of daily northbound
whales exceed southbound whales.
Unusual events:
- Southbound and northbound migrations overlapped: We spotted 49 northbound whales during the “southbound
migration.”
- We spotted 29 southbound whales during the “northbound
migration.”
- The northbound migration started somewhat early. It rose
to a very low plateau rather than a typical distinctive peak.
- “Peak” days and peak week set new record lows:
- Peak northbound count: 20 gray whales on 4 March and 15 March. (Previous peak
count range was 29-152.)
- Peak week: Only 81 gray whales were counted during the peak northbound week
of 13–19
March. (Last season, 158 gray whales were counted.)
The Gray Whale Population Status
NMFS (National Marine Fisheries Service) estimated the gray
whale population at 20,110 in 2007. Gray whales were
removed from the endangered species list in 1984.
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Los
Angeles, California
(33.44N,
-118.24W)
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Photo
Alisa Schulman-Janiger
ACS/LA
Census-takers on the patio of the Point Vicente Interpretive
Center. Point Vicente is in the background. Pictured (left
to right) are: Natalie Massey,
Linda Jebo, and Alisa Schulman-Janiger.
Members
of the public are also invited to join in and help spot whales at
the Point Vicente Interpretive Center. Call (310) 377-5370
for directions.
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