Tuesday, August 27, 2013

Whale Page # 2 from the San Juan Journal


Every August we do a special informational page in the local paper,
the San Juan Journal, all about the endangered Southern Resident Killer Whales. This year, Director Ken Baclomb is the author. We thought we would share them with all of you who don't have access to the San Juan Journal!
This is the second installment:

What do Orca Whales Like to Eat?


In the previous article in the Whale Pages, we presented the fact that the whales we call Killer or Orca represent a complex of many distinct populations that may prove to qualify as species; and, here we present the fact that these distinct populations specialize or “like to eat” particular prey species. All of the populations of so-called Killer whales are predatory animals currently assigned to one species (Orcinus orca, Linnaeus, 1758), and they must eat to survive; but, the preferred prey species for each population varies according to what is locally abundant and available in the marine ecosystem within swimming range. The classic studies regarding what “Killer” whales like to eat came from examination of stomach contents of these whales that were stranded in various locations around the world, or taken by whalers. The food items were fish, squid, seals, porpoises, other whales, etc. that led to the early conclusion that Orcinus orca was euryphagous, that is they fed upon a wide variety of prey and could switch diet if a particular variety became scarce. More comprehensive recent studies, including those done by the Center for Whale Research, indicate that each branch of the Orca family tree tends to strongly lean toward a prey species that is locally available and sufficiently abundant year-round for a very long time (many whale lifetimes). This tendency is termed stenophagy – a narrow variety of prey species; and, over the evolutionary time scales available from thousands of whale lifetimes it has resulted in very distinct differences in the anatomy and morphology of the various whale populations.


Transient killer whale with a harbor seal in it's mouth-
Photo by Dave Ellifrit
            “Transient” Orcinus orca whales may indeed be properly called “killers” (at least by the seals, sea lions and porpoises they consume), and they have very robust jaw structure with relatively big teeth (the better to bite you with, my dear). Their lifestyle is rather nomadic, as they travel with the seasonal migrations and/or the seasonal birthing and weaning cycles of their prey species. These mammal predator whales typically venture into the waters around the San Juan Islands in autumn and winter months when harbor seals are weaned (and unsuspecting), and when sea lions overwinter in the Salish Sea. Typically the “transients” travel in relatively small groups of 3-15 relatives and associates, and they are usually stealthy (non-vocal, so the prey species cannot hear them). This year (2013) we have witnessed an unprecedented influx of “transients” around the San Juan Islands, some coming from as far as California and Alaska. There are about 250 “transient” killer whales in the Center for Whale Research catalogue for this area.

Southern Resident, L84, with a salmon in his mouth-
Photo by Dave Ellifrit
           Orcinus orca whales may be properly called “Orca”, a term that is more fitting with the image of a peaceful non-stress-inducing population of mellow fish-eating predators with less robust jaw architecture and smaller teeth than “transient” killer whales. The “resident” lifestyle is adapted to the migrations and seasonal abundance of salmon in the eastern North Pacific Ocean. The salmon most available year-round within the “resident” swimming range are Chinook, or Kings, which happen to be the largest and most nutritious species of salmon in the world (formerly weighing up to 125 pounds each!). Chinook lifestyle, in turn, is predatory upon smaller fishes that are in greatest abundance on the continental shelf of the Pacific Ocean near the edge of upwelling currents. Chinook salmon have been taken in Human fisheries by the millions each year for the past century, and most wild populations of these fish are now “Endangered” with many already extinct. The “resident” Orca whales typically venture into the waters around the San Juan Islands in pod and multi-pod associations (Superpods) from May to September when the mature Chinook salmon are bound primarily for the Fraser River for spawning, though a few migrate to other river systems in the Salish Sea. Thus, we have an Endangered whale species obligate feeding upon an Endangered salmon species – a revolting development unforeseen by dam builders, habitat usurpers, and fishermen. As of 2013, there are currently 82 southern “resident” Orca whales in this population, down from nearly 100 twenty years ago, and down from more than 200 that we have catalogued. We have demonstrated that the “resident” Orca survival is significantly linked to Chinook abundance, and the government managers on both sides of the US/Canada border should take more notice of this inconvenient truth before it is too late. This year (2013) during the summer when whale-watching is historically best, we have witnessed an unprecedented absence of “residents” around the San Juan Islands, and a continuing downtrend in their population number concurrent with a near collapse of Fraser River Chinook.



Ken Balcomb

Director
Center for Whale Research

Monday, August 19, 2013

Whale Pages from the San Juan Journal


Every August we do a special informational page in the local paper, the San Juan Journal, all about the endangered Southern Resident Killer Whales.  This year, Director Ken Baclomb is the author. We thought we would share them with all of you who don't have access to the San Juan Journal!

Keeping an eye on local Orca whales 

            Whales of any species can be individually recognized by their natural shapes and color patterns using a technique called “photo-identification” that was pioneered in the 1960’s and 70’s by biologists at San Juan Island’s Center for Whale Research. The local “killer whales”, now affectionately known as Orca, are among the most distinctively appearing whales in the world, and many individuals can be easily recognized by naturalists and admirers of wildlife. To assist with this recognition, a photo-identification catalogue of every individual orca whale common to the Pacific Northwest has been maintained by biologists at the Center since 1976, and it is updated every year.
Above, L54 and her three offspring are shown as a family tree. 
The matriarch, L54, is at the top, with her descendants below, eldest to 
youngest from left to right. L117, who’s sex is unknown, is the youngest of 
L54’s calves, born in 2010. New born calves often have a grey and mottled 
looking saddle patch. Because calves stay close to their mothers for the first 
year or so of their life, they are often identified by their association with
their mother rather than their saddle patch. To identify older individual whales, 
look closely at the details of the saddle patch of each animal in the subgroup. 
Every orca whale has a distinct and unique saddle patch, 
much like a human fingerprint,  unlike any other whale in the world.

            




As a result of this cataloguing some very remarkable facts have been uncovered about the local Orca whales and about their species worldwide. For example, their natural lifespan is long (comparable to human lifespan to eighty or more years) and they travel in family groups (known as “pods”) swimming 75 miles per day on average. Three of these family groups, designated J,K, and L pods, are frequently seen travelling back and forth around the San Juan Islands from May to October; and, they have been termed “resident”. Other family groups and individuals are typically less frequently seen around the San Juan Islands; and, they have been termed “transient”. From long-term observation and genetic studies it has been learned that the “residents” and “transients” do not mix and interbreed – they are very, very distant relatives, somewhat analogous to Humans and Neanterthals but both living at the same time, and in the same general area.
            In fact, when we extend these individual and genetic studies we find that there are probably ten or more distantly related large branches of the Orca family tree worldwide that do not naturally mix or interbreed, and they have been on this planet much longer than we Humans have. Scientists are just now trying to determine whether this arrangement constitutes a complex of many species, and why. Nonetheless, we have a very precious “resident” population here in the San Juans, and they have been recently affirmed as Endangered under the US Endangered Species Act and Canada’s Species at Risk Act.
            The questions are out there, from deep pondering about the roles that species play in the web of life on Earth, to what time will the whales be seen at Lime Kiln whale-watch park. We do not yet have all of the answers, but if we keep our eye on the welfare of our precious local Orca whales we may just have a chance to find out how “our” world works, and maybe we will be smart enough to keep it working.
Eyepatches are important too!
Orca eyepatches are also an important marking
used for identification. Eyepatches, the white
patch above the eye, are unique to individuals just like
saddle patches. Sometimes we can’t get a good look at
the saddle patch, say when a whale spyhops, but we
can use the eyepatch instead to identify the individual.
This eyepatch photo is of the newest calf in L pod L119.

            In future editions of these Whale Pages, we will provide additional information about our famous Orca whales.

Ken Balcomb
Director
Center for Whale Research













Don't forget!  Membership Helps!  
To become a member of the Center for Whale Research and learn more about our local killer whale populations go to our website: www.whaleresearch.com

Candace Calloway Whiting