Monterey Bay Whale Watch conducted year-round trips during 1998 to observe
the diversity of marine life within the Monterey Bay National Marine
Sanctuary. Our biologists documented all marine mammal species including
location, group size, and behavior. We also photo-identified individual
humpback whales, blue whales, and killer whales, and contributed the
photo-identifications to scientists working on these species.
The year started off with the southern migration of the Gray Whale which was
a bit delayed due to El Niño conditions, and therefore late ice formation in
their Alaskan feeding grounds. This allowed the whales more time to feed
before the area became covered with ice. The migration peaked off Monterey
between the 2nd and 3rd week of January with over 50 whales sighted per
three-hour trip, with whale group sizes ranging from 10 to 15. The highlight of the
season was our observation of a Gray Whale giving birth to her calf inside the
Bay off Pacific Grove. There were several other mothers with newborn calves
observed during January as well. As the population increases it is not
uncommon for whales to give birth before they reach the Mexican lagoons,
although before this year no one had witnessed such an event in Monterey Bay.
For unexplained reasons the northern migration of the Gray Whale was early,
with the first northbounders observed during the second week of February. As
in past years, we observed several groups of mating whales during March, often
engaged in this activity for several hours. As the main migration of adult and
juvenile whales passed us in early April, the migration of mothers with calves
was just beginning in our area. This is a time of danger for the young calves
as Killer Whales prefer to hunt them in Monterey Bay as they cross the deep
canyon and are away from the protection of shore. Our biologists, who focus on
Killer Whale research in Monterey Bay, worked with the BBC Natural History
Unit during this period to study and film Killer Whale attacks on Gray Whales.
Although this is an unpredictable event, we observed three full attacks and
the end of a fourth. The Killer Whales generally work as a group to tire the Gray
Whales, separate the mother from calf, and eventually kill the calf, often
taking up to 6 hours to complete. All the Killer Whales involved have been
previously identified in the Bay and are included in our published killer
whale catalog.
Spring marked the beginning of the upwelling season,
coinciding with the arrival of Humpback and Blue Whales to feed on the
abundance of fish and krill in the Monterey Bay region and along the central
coast. May and June offered incredible opportunities to watch multi-species
feeding aggregations in the Bay involving Humpback Whales, thousands of Long
Beaked Common Dolphins, hundreds of California Sea Lions and up to 10,000
seabirds, mostly Sooty Shearwaters. The dolphins appeared to be herding the
fish towards the surface and the Humpbacks would cooperatively lunge up through
the fish in groups of twos or threes. People who witnessed this could not
believe the tremendous concentration of species in a relatively small area.
This phenomenon was featured on the opening section of the CBS Sunday morning
news with just natural sounds and film.
As El Niño conditions seemed to subside and wind conditions became favorable for
pulses of upwelling, both Humpback and Blue Whales were consistently sighted
through the summer and fall period. An abundance of sardines and krill was the
mainstay for these whales. As during the winter and spring, Common Dolphins,
both long beaked and short beaked species were the most abundant dolphin in
the Bay through the end of fall, often encountered in groups of over 2,000
individuals. They displaced the normally abundant and frequently sighted
Pacific White-Sided Dolphin which was still occasionally present but in
smaller group sizes. Baird's Beaked Whales were sighted several times during
October, as in past years. Killer Whales were sighted 2-5 times per month with
peaks in spring and fall. October marked above average sightings and numbers
(1,000 per group) of Risso's Dolphins, often in the company of Northern Right
Whale Dolphins. As Risso's Dolphins are known to feed only on squid and on at
least 13 different species in the Bay, there were likely large concentrations
of squid at this time.
Another late burst of upwelling in October created huge krill concentrations
off the coast between Pt Pinos and south of Pt Lobos, near the canyon edge,
and lasted through most of November. This late season krill brought on some
days up to 100 whales to the area including Humpback Whales, Blue Whales and
Fin Whales. Fin Whales are not commonly seen in most years, but were a
consistent presence during October and November. In early December we started to see a few gray whales, and we expect to see normal numbers of whales during their migration period from December through April.