Very recently, Wrangell Island has become part of a mystery that is playing itself out on the Pacific Coast of the U.S. and Canada this year. The mystery is the "unusual mortality event", as stated by NOAA, of grey whales.
This is not the first of these "unusual mortality events", there was another in 2000 when 131 whales were found dead that year. So far in 2019, 167 whales have been found dead on beaches from Baja California to Alaska, primarily juvenile whales but also some adults, some emaciated, some not.
As with so many things involving the oceans of our planet, this mystery may never be solved with certainty but there are a few current thoughts and theories regarding this 2019 event.
But first, a little information regarding grey whales. Like so many whale species, grey whales were hunted commercially in the past and their population was reduced to possibly less than 1000 whales at one point. Their population has rebounded greatly with the estimated population of the northeastern Pacific grey whales last year at about 27,000 individuals. Their population is considered a success story of species recovery and they were taken off of the Endangered Species Act list in 1994.
Grey whales have baleen so feed by taking in a large volume of water and prey animals and then pushing the water out through the baleen leaving behind whatever prey animals were in the massive mouthful. Grey whales are different than other baleen whales in that they scoop up mouthfuls of sediment from the ocean floor which they then strain through their baleen leaving behind small crustaceans called amphipods.
Grey whales like many whale species are migratory and journey annually from calving areas in the warm waters of the Pacific off of Mexico to the cold Pacific waters of northern Alaska, a migration of thousands of miles requiring who knows how many calories to accomplish.
Okay, here come the photos. I feel the need to first say that I took these photos out of a true compassion for the natural world and to document this individual's passing. I got up early in the morning the day after I learned of the whale and kayaked to where it was grounded on the beach. I wanted to see it to satisfy my curiosity but also to spend some time in the solitude of the early morning contemplating life and death. I'm glad I did it because the next day was when the necropsy was performed on it and it sounds like there was quite a crowd as seems to happen whenever a federal agency gets involved.
As you can see, the whale is on its back fairly high up on the beach. In the bottom picture, I put my paddle there to get some scale - my kayak paddle is 7 feet 3 inches long so you can get a little idea of the size of the whale. That thing on the right that looks like a rope is a rope which is one of two that are anchoring the whale to some trees so it does not float away before a necropsy can be performed.
I kept a close watch for bears while I was here but there was very little smell yet as the days were cloudy and cool and there were no open wounds. I'm sure the bears have found the whale by now after it has been opened up by the necropsy and there have been a couple of fairly hot sunny days. This will be quite a macabre feast for the bears, eagles, and ravens for probably quite some time.
The current theories regarding this "unusual mortality event" of grey whales mostly involve climate change related ideas of course as climate change is the catchall reason for anything we think are "out of the ordinary". Warmer sea waters may have disrupted some aspects of the ecosystem affecting the food items of the whales or maybe the lessening sea ice in the Arctic may be creating a scenario where the whales have to migrate farther to find food items associated with the ice. A non climate change theory that is also in a sense a "good" thing is that maybe the grey whale population has increased in numbers to the point that they have exceeded the carrying capacity of their environment. I've never understood why we are always so eager to attribute some phenomenon to one specific cause rather than a combination of causes. Maybe it is a combination of all 3 of these plus some others or maybe it is a combination of others yet untheorized. Fukushima radiation maybe? Plastics in the oceans? Disease? I won't jump to "the sky is falling" conclusions yet as everything dies and this hasn't been a regularly occurring event.
Now for a photo of the creepy animals I cautioned about earlier. These animals are crustaceans called whale lice and they live on whales. They do not seem to harm the whales and likely benefit them despite their creepy and mildly scary appearance. The whale lice are more commensal than parasitic meaning they don't harm the whale or cause it stress of any kind, in fact, they can help the whales' health by eating the dead skin and flesh around wounds and by preying on parasites that may try to infest the whale. Different species of whales have their own species of whale lice and it has been discovered that female sperm whales have a different species of whale lice than male sperm whales. They are actually pretty interesting but I have to admit that their appearance doesn't make me want to spend much time looking at them or studying them.
Yeah, not something I would want on me regardless of any health benefits they might offer. They are strange looking things aren't they?
I'll finish with a few photos of a much cuter animal than a dead whale and whale lice. As I paddled around a point, I saw a river otter ahead of me swimming in the same direction as I was paddling. The otter would swim for a bit and then dive for a few moments before coming back to the surface chomping on something it caught. It did not notice me for several minutes so I was able to get a little closer and keep tabs on it when it was under the water by the stream of bubbles that gave away its submarine position. Just to clarify, this is a river otter not a sea otter even though it is in the sea. River otters are much more interesting, active, and fun to watch than sea otters.
So interesting .
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