By Nancy Black,
Marine Biologist and Owner of Monterey Bay Whale Watch
Click on small pictures below to see full-size photos.
The best chance to see Killer Whales in Monterey Bay is
in April and May. Although they aren't here every day like the humpback
whales, we often see the Killer Whales at that time of year as they come
to Monterey Bay to hunt gray whales. In mid-April 2011, the humpback whales
are just arriving, more each day and they will be feeding here through summer
and fall. Nancy Black, marine biologist for Monterey Bay Whale Watch, has been studying the killer whales for close to 25 years and her work with these whales and as they hunt gray whales has been featured on National Geographic, Animal Planet, Blue Planet Series, The Today Show and many other news sites. She prepared this feature story to provide information about wild Killer Whales, with special emphasis on the Killer Whales of Monterey Bay. I would like to briefly describe the lives of wild Killer Whales in Monterey Bay, off central California. Killer Whales occur year-round in Monterey Bay, although on an unpredictable basis. We can encounter them on our whale watching trips any time of the year, although the peak time for sightings is April and May, when they frequent Monterey Bay to hunt Gray Whale calves. In addition to Killer Whale sightings, our Monterey Bay Whale Watch trips focus on watching Humpback Whales, Blue Whales, Gray Whales, several dolphin and porpoise species, seals, sea lions, and sea otters. It's not unusual for us to see groups of thousands of dolphins, as Monterey Bay is an extremely nutrient-rich and productive area for a tremendous diversity of marine life. Given this large diversity of marine mammals that feed or migrate through Monterey Bay, Killer Whales frequent this area to hunt other marine mammals as their natural prey, making Monterey Bay an ideal place for me to conduct my year-round and life-long study of these truly amazing, highly intelligent social mammals. Types of Killer WhalesThree different eco-types of Killer Whales occur in Monterey Bay: 1) Transient Killer Whales (mammal hunting), 2) Resident Killer Whales (fish eating), and 3) Offshore Killer Whales (feeding on fish, sharks, and squid). Each population type is genetically distinct from the others, and they do not interact among types. They have distinct vocalizations, look physically different to the trained person, exhibit different social groupings and hunting tactics, and specialize on different prey. They may eventually each be considered separate species, as they do not intermix. Resident Killer Whales Visiting Monterey Bay I
was the first to discover that the "resident type" or fish hunting Killer
Whales that are normally found in the Pacific Northwest (Southern Residents
- J, K, and L pods) traveled all the way to Monterey Bay. Since this first
sighting in 2000, we have observed them at least once during the winter
on several years since then. These whales are now considered endangered
as their preferred food source, Chinook Salmon, has drastically declined
and the Killer Whales appear to have expanded their range in search of
these fish. All our sightings of these whales are immediately reported
to Ken Balcomb at the Center for Whale Research in Friday Harbor, Washington
as Ken has been studying this group for over 30 years. See our earlier
feature articles about Resident Killer Whales in
Monterey Bay in 2000 and again in 2003. Offshore Killer WhalesLess is known about the Offshore Killer Whales as they are unpredictable in occurrence and we generally observe them during the winter, in large groups of 50 -100 whales. We found that these whales have the longest range movements discovered so far for any Killer Whale population and we have recently co-authored a scientific paper on them. Individual whales identified in Monterey Bay have traveled to southern California and as far north as the Bering Sea in Alaska. Transient Killer Whales The "transients" or mammal hunting Killer Whales are the type most frequently
sighted in Monterey Bay and we have over 130 individual whales in our
catalog. The whales seen in Monterey Bay range from southern California
to Washington, with a few sighted as far as British Columbia and Alaska.
Certain groups are seen more often than others with a home range centered
more around Monterey Bay. These whales are famous for hunting Gray Whale
calves in Monterey Bay during the spring and our work with these whales
has been featured on many nature programs on Television. For one example,
see our feature about the National Geographic Explorer
TV Program on Killer Whales of Monterey Bay. Killer Whale CultureKiller Whales are true predators and are highly intelligent, social mammals living in a matriarchal society (with groups based on adult females and their offspring), exhibit complex communication patterns (similar to a language), and exhibit culture - with hunting strategies and knowledge of where to find prey, time of year to find specific prey and how to hunt different prey species successfully passed on among generations by females to their young. Even the males will generally stay with their mothers through life and mate with different family groups that are not closely related to them but still part of their population type. Females can live up to 80-90 years and males 50-60 years, with males reaching lengths of 30' and 6 tons and females up to 26' and 4 tons. Killer Whales Hunting Dolphins in Monterey Bay As
a recent example of the natural life of these incredible animals, I am
including photos of a recent event, as it is impossible to describe here
all the amazing predation events we have observed over the years. On January
10th of this year (2010) on our whale watching trip we encountered a group
of over 800 long-beaked common dolphins as they were fleeing from a group
of eight Killer Whales. The dolphins were flying out of the water at high
speed away from the Killer Whales. We passed the dolphins and caught up
with the Killer Whales just after they caught a dolphin. When hunting
dolphins, Killer Whales often track a distance of a quarter mile or more
behind the school without alerting the dolphins to their presence. The
Killer Whales are usually spread out over several hundred yards and wait
for an opportunity to catch a dolphin by surprise. The whales will try
to isolate a dolphin and come from below and often will toss the dolphin
in the air by their head or flukes, while the other Killer Whales will
all gather and several whales will work together to eventually kill the
dolphin.
Rewards of Viewing Whales and Dolphins in the WildI
expressed to everyone that seeing Killer Whales in the wild is so much
more rewarding and enriching than watching them in captive "shows" where
they are kept in an unnatural and small environment for such highly intelligent
social animals. Times have changed and I think many people would prefer
to see animals in their natural environment rather than in a captive situation
where they are made to perform for crowds of people. Chemical Contaminants and Killer Whales During my research in collaboration with the National Marine Mammal
Laboratory (NOAA) I collected small biopsy samples of several different
Killer Whales and found that the whales have extremely high levels of
chemical contaminants such as PCB's, DDT's, and flame retardants, all
of which can be detrimental to these animals by affecting their reproductive
rate and immune system. However, it's hard to prove a direct link from
these chemicals to physical effects on the whales. About Nancy Black and Monterey Bay Whale Watch Besides leading whale watching trips as captain and marine biologist/naturalist
guide, Nancy Black has also been conducting research on these whales for
over 20 years and often uses her small research inflatable for this purpose.
She has co-authored several research papers on these whales (see list
below), published and was lead author on the first photo-identification
catalog of Killer Whales for California and Mexico (as each whale can
be identified by distinct markings on the dorsal fin and saddle patch),
provided updated research poster presentations during each Biennial Conference
for the Society of Marine Mammalogy (see PDF
of this poster), often gives public presentations on Killer Whales
(for such organizations as the Monterey Bay National Marine Sanctuary,
Monterey Bay Aquarium, American Cetacean Society, Long Beach Aquarium,
Long Marine Laboratory/UC Santa Cruz, Point Lobos State Reserve Docents,
and others); and her research has been featured on many nature shows (Blue
Planet - Discovery Channel; Secret Killer Whales of Monterey Bay - National
Geographic; Whale Attack - Animal Planet; Killer Whales/Gray Whales TV
Series with Jean Michael Cousteau of Ocean Futures on PBS, and others). Research Papers Co-authored by Nancy Black Harbor Porpoise Mortality
in the Monterey Bay Halibut Gillnet Fishery, 1989 (1994) Additional Photos
LinksKiller Whales approaching boat with prey (Roger Wolfe video on YouTube) Killer
Whales attacking a baby gray whale (BBC video on YouTube, narrated
by David Attenborough) |
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