ACS/LA
GRAY WHALE CENSUS AND BEHAVIOR PROJECT: 2008-2009
By
Alisa Schulman-Janiger [email: janiger@bcf.usc.edu
or janiger@cox.net] [web: www.acs-la.org/GWCensus.htm]
Fifteen marine mammal species including breaching
humpback whales and record numbers of lunge-feeding fin whales and of bottlenose
dolphin - including a bottlenose dolphin birth - kept enthusiasm high, while
near record low gray whale counts frustrated us during the 2008/2009 ACS/LA
Gray Whale Census and Behavior Project. This is the 29th year (26th
consecutive season) that the American Cetacean Society's Los Angeles
Chapter has sponsored a gray whale census project from the Palos Verdes
Peninsula. Our cliffside post is on the patio of the Point Vicente Interpretive
Center (PVIC), 125 feet above kelp beds and rocky shoreline, with a seafloor
that drops off abruptly nearshore. Trained volunteers collect data on gray
whales and other cetaceans (identifications, counts, and behaviors). All participants
use binoculars; several use spotting scopes to confirm and detail sightings.
Weather data (visibility and sea conditions) is recorded at least hourly.
COVERAGE: Our census station operated
for 1944 hours over the 166 days between 1 December 2008 and 15 May 2009
(averaging nearly 12 hours/day). 66 volunteers contributed 7307
effort hours. The eight core volunteers that donated over 200 hours
each, totaling 36% of our effort hours (and the number of volunteered
days) include: Joyce Daniels (163), Natalie Massey (107), Linda Jebo (81),
Steve Gardner (80), Libby Helms (76), Nancy DeLong (58), Bob Jensen (54),
and Cynthia Woo (37). Nineteen additional volunteers donated at least 100
hours each.
NUMBERS OF GRAYS COUNTED:
Both northbound and southbound counts were our 2nd lowest on record.
Observers saw fewer southbound but more northbound gray whales this
season: 303 southbound and 677 northbound gray whales (461 southbound
and 634 northbound whales last season). Over 25 previous seasons, counts
have greatly fluctuated: southbound numbers varied from 301-1291, and northbound
counts varied from 634-3412. Although most of the estimated 20,000
gray whales migrate past California, we spot only a small proportion.
Gray whales - especially adults - off Palos Verdes tend to travel further
offshore, notably during the southbound migration. Northbound whales - particularly
cow/calf pairs - tend to hug the coastline. These trends, combined with extended
springtime observation hours, produce higher northbound counts. Shifting
migratory corridors and weather conditions result in annually fluctuating
shore-based counts. The number of whales that complete the migration varies,
and feeding ground conditions (especially ice coverage) affect migratory timing
and corridors. Poor visibility drastically affects counts; fog impacted us
less often this season (on 29 days, compared with 80 days last season), but
fog and wind did hinder sightings during the northbound calf pulse.
PEAKS AND TURN-AROUND DATES:
This season's peak days matched our lowest recorded counts. We saw
15 gray whales on our peak southbound days of 11 January and 18 January
(previous peak counts ranged from 15-98). We spotted 56 southbound whales
during the peak southbound week of 18-24 January (124 last season). Our official
turn-around date (when daily northbound whales exceed southbound whales)
was 7 February - our earliest turn-around so far (one month earlier
than last season). This season's migration seemed to be a long "gap
period", with few whales passing our station - except for early March.
We counted 15 northbound whales during the southbound migration period, and
43 southbound whales during the northbound period. Our peak northbound
counts were 29, on 4 March and 7 March (previous peak counts ranged from
29-152). We recorded 158 whales during the peak northbound week of 4-10 March
(153 last season).
CALF COUNTS FALL: Although
calf counts fell, we saw more southbound and more northbound cow/calf
pairs than in nine of the past 25 seasons. We spotted 18 newborn southbound
calves (5.9% of southbound migrants) from 27 December-10 February, peaking
with 3 calves on 11 January. (Last season we saw 25 newborn calves: 5.4%
of the southbound migrants). This is our 5th highest newborn calf percentage;
the record occurred during the 1997-98 season (106 calves - 8.6% of southbound
migrants). Previous southbound calf counts ranged from 3-60 (0.5%-8.9% of
southbound migrants). We counted 52 northbound calves (7.7% of northbound
migrants) from 28 March-13 May, peaking with 5 calves on 28 April.
This was our 13th highest calf percentage. (Last season we counted
63 northbound cow/calf pairs: 9.9% of northbound migrants). Besides the record
of 222 calves (1996-97), previous calf counts have ranged from 11-196 (0.9%-18.5%
of northbound migrants). In addition to the calf counts listed above, there
were probable sightings of 5 cow/calf pairs (3 southbound and 2
northbound). Experienced observers are needed to spot calves, especially
southbound, since many cows keep a low profile.
BEHAVIORS AND HUMAN INTERACTIONS:
We saw gray whales mill, roll, lunge, breach, spyhop, bubble blast, and nurse
calves, and saw pods merge and separate. We witnessed five near-collisions
as private boats nearly ran over gray whales; these whales became low-profile
or disappeared, and one pod split up.
LOW COUNTS: Our very
low gray whale counts and reduced calf counts reflect trends seen by coastal
census stations such as that run by NMFS (National Marine Fisheries
Service), who conducts the official gray whale census. They estimated
the gray whale population at 29,758 in 1998 (a 35 year high), 18,178
in 2002 (following a major mortality event), and 20,110 in 2007.
Gray whale counts are impacted by fluctuations in wild populations and the
number of whales that complete the migration, weather conditions, and observer
experience. Feeding ground conditions affect migratory timing and paths.
The gray whale population dropped with a major mortality event (1999 and 2000),
followed by three seasons of low calf production. When gray whales altered
their foraging behavior, strandings decreased and calf production increased.
Over the past several years, Arctic warming has led to increasingly smaller
icepacks. Gray whale prey - mud-dwelling shrimp-like amphipods - shifted
northward: they thrive in cooler water, feeding on algae that fall from
ice sheets. Gray whales forage further northward following prey distribution,
which can delay migration. Whales may ignore the initial migration cue (shortened
daylight hours) so that they can rebuild blubber that allows them to fast
during migration and on Baja nursery grounds, and provides energy to withstand
disease, storms, and killer whale attacks. Last summer NMFS reported
that cooler weather created larger Arctic icepacks, which made it more
difficult for gray whales to forage; less available food can lead to fewer
successful pregnancies. We saw a few skinny whales this season.
Key indicators of a healthy population are higher adult and calf counts,
both of which factored into the National Marine Fisheries Service (NMFS) decision
to recommend the removal of gray whales in 1994 from the endangered species
list. Lower calf counts along several coastal census stations are causing
some concern. A developing El Nino may bring heavy storms
and increased strandings of newborn calves and vulnerable juveniles
next season.
OTHER SPECIES SIGHTED:
This season we spotted at least 14 other marine mammal species! Highlights
included record numbers of fin whales and bottlenose dolphin, a bottlenose
dolphin giving birth, and a sea otter eating lobster! Comparing
this season (to last season), we saw common dolphin on 144 days (126),
bottlenose dolphin on 138 days (124), fin whales on 91 days
(41), Pacific white-sided dolphin on 63 days (41), humpback whales
on 27-31 days (25-30), Risso's dolphin on 6 days (28), minke whales
on 4-6 days (8-9), blue whales on 4 days (9), 4 killer whales
on 5 May (2-3), a female Cuvier's beaked whale on 14 May, unidentified
large fin or blue whales on 12 days (13), other unidentified whales
(including a possible Bryde's whale) on 15 days (4), unidentified dolphins
on 2 days (1), California sea lions almost daily, a harbor seal
on 3 days, a sea otter on 2 days (1), and an elephant seal on
1 day (3). (Unfortunately, we were not able to take photos of these killer
whales. You can contribute to our California killer whale photo-identification
project by sending photos and sighting data to: janiger@cox.net; we will
try to match images to our catalog, and notify you with the results). Other
species sighted in past seasons included sperm whale, false killer whale,
pilot whale, northern right whale dolphin, and Dall's porpoise. Gray whales
interacted with other marine mammals including sea lions and bottlenose
dolphin. We occasionally recorded groupings composed of mixed species
of dolphins and sea lions. On one day each we saw 1 osprey and 1 peregrine
falcon: both are species recovering from DDT contamination.
OBSERVERS' HOURS: This
project would be impossible without the following dedicated whalewatchers
(with their volunteer hours: * = new observers): Joyce Daniels - updated
graphs (625), Libby Helms (444), Nancy DeLong (305), Natalie Massey - summarized
guest book (280), Bob Jensen* (262), Steve Gardner* (259), Cynthia Woo (240),
Linda Jebo (233), John Nieto (178), Stephanie Bryan (169), Joan Venette (167),
Clyde Lambert (161), Pat Harpole (140), Carol Harrison* (140), Terry Hayes
(140), Michael White (139), Stephanie Brito (130), Corinne Sutherland (128),
Ann Gardner (126), JoLinda Garnier* (120), Dee Whitehurst (120), Jo Bonds
(130), Dee Liter (119), Robin Riggs (116), Tina Hoff (109), Barbara Stone
(102), Larry Desy (100), Kim Watson (97), Hugh Ryono (96), Pam Ryono (92),
Karin Campbell (89), Joyce Jessoe (87), Peggy Gilliam (86), Amy Heintz* (85),
Ted Lester (85), Tony Carrillo* (85), Gary Harper* (83), Mike Malone (82),
Evi Meyer (81), Cathy Landrum (75), Erlinda Cortez (70), Susan Lyons* (67),
Danny Gonzalez (65), Allison Riehl* (64), Lacey Brandt* (60), Dave Morse (60),
Beth Larson* (59), Cynthia Ryan* (55), Gerrie Cole (54), Darryl Kelly* (50),
David Taylor (28), Andy Veek (46), and Alisa Schulman-Janiger (41). Volunteers
who donated 20-39 hours each included: Fran Austin - veteran from Colorado
(38), Linda Barkley (35), Kevin Butler (35), Deborah Wuliger* (25), John Simpson*
(24), Priscilla Rodriguez (22), and Donna McLaughlin (21). Volunteers with
10-19 hours each included: Blake Lyons*, Daniel Chavez*, Bob Daniels, Pete
Treanor, Jean Gallagher and Kris Clifford..
IN MEMORIUM: Beloved volunteers who passed away this year: Clyde
Lambert - February 28 (8512 hours over 23 seasons), Dave Taylor
- July 12 (960 hours over 16 seasons), and Joan Venette - August 2
(17,151 hours over 23 seasons). We will miss these treasured, enthusiastic
whalewatchers who contributed so much to our project!
COMPUTER ENTRIES: We especially thank Dave Janiger for computer entries.
GUESTBOOK
LOG: 1409 visitors from 45 states in the USA (mostly California, Ohio,
and Texas), and 192 from 42 foreign countries (primarily England, Germany,
and Canada).
JOIN US! To
join our census project, contact Alisa Schulman-Janiger at: janiger@cox.net.
No experience is necessary: on-site training in November and December.
Highly recommended: attend the Whalewatch Training Class at Cabrillo
Marine Aquarium (CMA) [(310) 548-7563; www.cabrilloaq.org], co-sponsored
by CMA and ACS/LA (www.acs-la.org). On Tuesday nights, October-March,
volunteers are trained to become Whalewatch boat guides and classroom lecturers.
ACS/LA offers free lectures from invited specialists the last Tuesday of
each month at the Cabrillo Marine Aquarium, and all day whalewatching
trips to Santa Catalina Island for gray whales, and to the Santa
Barbara Channel for humpback whales and blue whales.
**This copywrited protected
data is provided as a public service. Please contact the project director
for permission to cite in publications. **