Hello Everyone, The wonderful Baja 2020 season in which the Sea of Cortez came alive
once again has come to a close. And with the self isolation period most of us are now in
I found the extra spare time to process all the whale data in these first 3 weeks back home.
Following are some conclusions I think everyone will be interested in.
We identified 40 different blue whale individuals in the 2020 season. This was our best year in the past 5 years but still well short of our single season record.
24 of these 40 blue whales were anywhere from slightly to noticeably thin, which certainly captured our attention, but did not raise any major concerns.
We identified 23 different fin whale individuals, our all time record for this species. We did not observe any thin individuals in this species that feeds on both krill and small fish.
We identified only 7 different humpback whales.
We documented, with video, a young gray whale bottom-feeding in San Basilio Bay. We believe this to be a first documentation on film of a gray whale bottom-feeding anywhere in the Sea of Cortez.
There was krill in great abundance this season, and the whales were observed on numerous days having their fill of the krill.
We collected 13 large whale fecal samples from blue, fin and humpback whales. These will be lab tested for micro-plastics. Stay tuned for the results.
Additionally we observed 3 dwarf sperm whales, 2 gray whales and 1 Brydes whale. Dolphin numbers were about normal, meaning there were
were many dolphins sighted, with numerous very large pods of many hundred or even a few thousand. Pelagic bird numbers were about normal
but the abundance of boobies, both blue footed and brown, were easily the highest ever observed in our 25 years down in Baja. Offshore pelagic birds
such as storm petrels and shearwaters were strangely almost entirely absent. Sea lion numbers were down a bit and red blooms of plankton were seen on
multiple occasions. Many whales stayed around for most or all of the entire 7 week season, and some of them made some really interesting or long distance
movements within our working area. The season was quite cloudy and cool, and we saw more days with at least some rain than we had seen in any of our
previous 24 seasons.
What really caught my attention was this simple fact: 60% of the blue whales we observed were thin. It must be noted that most of these were not very thin, just noticeably thin. During their long migration to the Sea of Cortez certainly they can shed some weight. But the number of individuals that were slightly thin rather that the severity of weight loss (which we have seen in previous years) was what caught my attention. In great contrast not one single fin whale was thin. Fin whales are more flexible in their feeding strategies than blue whales are, supplementing their krill diet with large amounts of small fish such as sardines, anchovies and capelin. Blue whales have not evolved to take advantage of these other species and are krill feeding specialists. Additionally many of the fin whales we see in Baja are year round residents of the Sea of Cortez, while the blue whales migrate into and out of this sea each year. Each and every fin whale was robust. No conclusions can be derived from this difference between the appearance of the 2 species bodily conditions in one season, but for sure we will be taking a very close look at the condition of the blue whales we see next year, especially at the onset of the season.
A new blue whale we called Luna must be mentioned. Luna was seen only once very late in the season. Never before have I seen a blue whale with a
chunk this large missing from the fluke. It appeared as if a giant mouth took a bite and removed almost 1/3 of the entire fluke of this whale. He or she will be easily recognized if ever seen again, and this sighting will not be forgotten anytime soon. Luna can be seen in our Flukes of Baja 2020 attached image.
And finally there is the whale we called Pinocchio. This light colored fin whale has a huge dorsal fin, in the oddest of shapes, and spent ample time in the presence of blue whales. Pinnohio's side view highlighting the size of it's dorsal fin is attached.
But the oddest thing was that when Pinocchio dove he or she pulled it's fluke up high each and every time. This is only the 4th fin whale in my life I have seen dive and regularly pull it's fluke above the surface. We did wonder if this whale was a fin whale/blue whale hybrid, and yes those hybrids, although rare, are known to exist. This whale's lovely full fluke can be seen on the attached Flukes of Baja 2020 image as the first fluke in the upper left corner. We were blessed to see Pinnochio on multiple days this season and won't soon forget this whale. He or she will be easily and instantly recognized if ever seen again.
Before departing I will add that it was a vibrant year, and the sea was highly productive. Seeing all these whales feeding for close to 2 months in this
protected body of water where there are few people and little industry made me think. This place whether designated so or not is a sanctuary for the whales and many other forms of life. It is a place they can come to or live in and gather fulfill the energetic requirement they will have for the remainder of the year whether leaving on long migrations, or traveling to other parts of this sea for summertime. And they are very safe here, with few ships or large boats, and a low amount of nets being placed. 25 years in the books here for me, my second home, this great and rich sea a place I have come to deeply love.
Another report or two may come your way during 2020, if and when any interesting discoveries are made from what we encountered in the 2020 season.
Goodby for now and the very best to all, Michael
Images are of in order:
The magnificent flukes of Baja 2020
Pinnochio the fin whale, or is this whale a fin/blue hybrid?
Gray whale juvenile expelling mud while bottom feeding in Bahia San Basilio
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