5/3/15

Log for May 3, 2015

Our Sunday morning started off with a female veteran humpback named Mars going to town on some sand lance. I call Mars a veteran because she is visibly weathered and has clearly come across her fair share of obstacles throughout her life. If you look at her fluke (which was posted in Saturday’s log), you can see that something at one point carved a huge chunk out of her right fluke. If you look at her tailstock, you will also find a deep indentation around her peduncle. While I’m not in a position to say for sure what has caused these injuries, they are very consistent with entanglement scars and are likely anthropogenic in nature. 

Putter kick feeding

Despite such setbacks, Mars has continued to produce a healthy and resilient line of offspring (more on that later) and is actually mother to one of our local favorites. If you guessed Nile, you are correct! Mars spent her morning fishing for sand lance with bubbles and powerful surface lunges! We had great views of the her enormous throat grooves which function to maximize the volume of water she can filter, making these energetically costly lunges worth her while.

Unidentified humpback breach

Nearby, we had a feisty juvenile exhibiting a behavior that I sometimes call (though it’s definitely not scientifically termed) breach lunging (see photo). This little guy could have easily been mistaken as a calf had he/she not been displaying grown up whale feeding behavior. The one-sided facial scarring was also a give-away as it is evidence of bottom side-rolling, another grown up whale feeding behavior. That being said, we saw our fair share of calves rocking fresh facial scars towards the end of last season, likely from mirroring the behavior of their mothers’ feeding, maybe even catching a fish or two in the process.

We also had a set of humpbacks displaying synchronized lunges who put on quite a show for us! One of these individuals showed fresh injuries on its tail stock right behind its dorsal fin. Born last year to Lichen, it is this juvenile’s first season alone on the feeding grounds. Most of these young, returning whales will pick up battle scars as they learn the ropes in this multifunctional, shared habitat. Though I have an idea, it’s unclear as to what specifically caused these injuries.

Sei whale skim feeding

While we had awesome humpback activity this trip, I can’t forget to mention the gorgeous skim-feeding sei whales we enjoyed yet again Sunday morning. In total, there were seven to eight of these sei whales in the mix with these humpbacks. At one point we found ourselves in a situation I like to call whale soup! No complaints here. That is a dream come true for most whale watchers!

By the afternoon, the sei whales had moved on to brighter pastures (AKA thicker copepod patches). Nonetheless, we found humpbacks aplenty, and many of these were now kick-feeding. Tornado, Strike and Putter were among these humpbacks. We had a lot of fun watching this feeding activity as each whale worked the bait in different ways.

Putter's ventral pleats splayed as he filters a mouthful of food
Tornado's enormous open mouth
More snacking for Putter

Putter’s behavior was extra exciting to observe as he lifted almost half of his body perfectly vertical out of the water with each kick (see photo). This gave us a clear view of his genital slits reaffirming what we already knew, that he is of course male! Being another offspring of Mars’s and half-brother to Nile, seeing Putter brings us back to the subject of Mars’ matriline. It’s amazing how many generations scientists have been able to track and learn from over the past 40 years. To learn more about this matriline and the anthropogenic threats they have resiliently faced, follow this link to NOAA's page about Nile

— Tasia Blough

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