Did you know that they can identify Humpback whales by the underside of the flukes (the whale tail)?
Did you know that you can see where the gray whales are feeding off of Everett Washington on Google earth?
The 2017 Lecture Series hosted by Friends of Skagit Beaches started on Friday, January 20th with research biologist John Calambokidis who works with the Cascadia Research Collective.
Dr. Calambokidis put on a great presentation detailing some of the latest findings on the other whales that utilize the Salish Sea.
Regarding Humpback Whales:
The SPLASH study - Structure of Populations, Levels of Abundance, and Status of Humpbacks - involved over 400 researchers from 10 different countries between 2004 and 2006 in the Pacific Oceans. It was the largest collaborative study of its kind and its goal was to expand the working knowledge around migratory patterns for Humpback whales. Using photo identification (those flukes) and genetic studies some very interesting data was unearthed.For your own reading: SPLASH study information
First of all, the study identified approximately 20,000 animals. Dr. Calambokidis described one of the primary patterns that they discovered was that humpback "herds" stayed loyal to certain feeding areas. You might have multiple "herds" in Hawaii but they would travel to different areas in Alaska or the Bering Sea for feeding.
Researchers have been able to identify 14 distinct populations around the world. Some of these populations have been delisted from the Endangered Species Act, while some are listed as threaten or endangered. As an example, the Hawaii population has been delisted, while the Mexico population is listed as "threatened" and the Central Americal population is listed as "Endangered." All of these population migrate north and feed in the cold waters off of Alaska.
A question: How do we apply conservation where it is needed?
Another question that has arisen due to the fact that the number of whales seems to have leveled off - has the Pacific reached its carrying capacity for Humpbacks?
As a matter of fact, there have been areas of expanded territories - which includes San Francisco Bay and the Salish Sea. In the Salish Sea, the estimated abundance has gone from about 100 - 500 from 1995 to 2016.
The fact is, however, that the humpbacks are returning to the Salish Sea - they were here before. They were abundant enough that in the early 1900s there was a whaling station off the south end of Vancouver Island. That whaling station decimated the humpback population. It is hypothesized that it has taken this long for the humpback whales to recolonize this region.
More on Humpback whales
And then there are the Gray Whales:
The Eastern Pacific gray whales breed off the coast of Baja and travel up along the coast to the Artic waters. There are many subsets of this group that are designated by their feeding areas. The subset of most interest to us here in the Salish sea has the designation PCFA (Pacific Coast Feeding Aggregation) - but the feeding areas are further broken down into SJF (Strait of Juan de Fuca), NWA (North Washington Coast), and SVI (Southern Vancouver Island). Only a small number - estimated around 200 - gray whales are sticking around the Salish Sea over the summer months (sighted between June 1 and November 30th) while most migrate much farther north. Read the study.(And if I have some of my facts wrong or confused, let me know!)
A question the Macah tribe needs to currently answer is which population they can take their yearly quota of whales from.
One of the most interesting activities Dr. Calambokidis talked about was the high risk feeding strategy that some gray whales are engaged in here. Off the east side of Whidbey Island where the muddy sediment is rich with ghost shrimp, these gray whales are feeding in sometimes six feet of water.
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Gray whale feeding pits off of Everett courtesy of Google Earth |
Findings have found that the years when the number of gray whales is higher who practice this off-migration feeding corroborates data on gray whale strandings and mortality events. This makes sense given how shallow the waters are in the specific area where the whales are feeding. Dr. Calambokidis and his team were asked to come in and determine whether the whales were feeding in any other areas and through the use of tag sensor data, they found out that the gray whales were exclusively going after the ghost shrimp in the shallow waters.
One of the things that seemed to come out of this gray whale study - or at least the impact I felt - was that by collecting data on the activity of the whales helped answer a very specific question regarding the needs of the animal - and helped humans craft a response.
Dr. Calambokidis then spent some time talking about different tagging strategies that have been used. Satellite tags are anchored in muscle and last longer but the the data collected is very limited. Limpet tags have a more medium duration and again, are invasive - thru the skin. There are concerns and issues with both of these types of tags especially after one of the southern killer whales washed up on shore after being tagged with the limpet tag. Dr. C and his team use suction cup tags that record a ton of data but may only stay on for a day at most. Retrieval has been tricky on a few tags but the amount of archival data - including video - has been phenomenal.
Here's a video of his team tagging a humpback - with video off the whale's tag: Video Tag Deployment
Dr. C, in talking about the different types of tags, says you have to consider whether or not the impact of the tag is worth the invasiveness; you have to weigh the worth of what you are trying to learn against that impact.
He talked about some of the work they've done with the NRDC and the Navy regarding sonar and whales. I've got some ready to do on those studies. Another way that the collection of data has led to some limited human change was done in a study of blue whales off the coast of Los Angeles. The areas that the blue whales feed and travel was directly under the shipping lanes. After determining that the whales were not responding to shipping traffic by getting out of the way - and they travel quite slowly - the shipping lanes were moved a kilometer. Same in San Francisco. Small steps - but at least they responded.
The takeaways from the lecture, in Dr. C's words were this:
- Migration patterns are much more complex than we have known.
- Humpback whales stay loyal to regions and will switch prey before leaving those regions while...
- Gray whales move with the krill and respond to conditions - which is why some of them practice the high risk ghost shrimp strategy.
My takeaways:
- There are ways to incorporate the needs of other species into our human world of shipping lanes and naval maneuvering.
- We can't do that without the research and data that groups like Cascadia Research provide.
- When we see the complexity of behavior in another species, it becomes increasingly difficult to not see how our human actions impact these amazing creatures. It becomes very difficult to relegate other species to the 'dumb animal' category.
- It also becomes increasingly difficult to simply shrug the shoulders and say - these animals will simply adapt to changing conditions. By studying behavior and the ecosystem within which they move, we see how some species may attempt new adaptation strategies - but are hamstrung by human behavior such as noise pollution, sonar, toxins in the water.
- Basically, the more we know about these complex creatures and the ecosystems that overlap with our own the more we humans can understand how we are just one of many creatures who depend on a healthy environment to thrive.
Sources:
Calambokidis, J., J.L. Laake, and A. Klimak. 2010. Abundance and population structure of seasonal gray whales in the Pacific Northwest, 1998-2008. Paper SC/62/BRG32 presented to the IWC Scientific Committee.
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